W3147: Managing Plant Microbe Interactions in Soil to Promote Sustainable Agriculture

(Multistate Research Project)

Status: Inactive/Terminating

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Date of Annual Report: 02/21/2014

Report Information

Annual Meeting Dates: 12/06/2013 - 12/06/2013
Period the Report Covers: 10/01/2012 - 09/01/2013

Participants

Members Attending;
Ole Becker, (obecker@ucr.edu) - University of California- Riverside;
James Borneman, (james.borneman@ucr.edu) - University of California- Riverside;
Darin Eastburn, (eastburn@illinois.edu) - University of Illinois;
Kathryne Everts, (keverts@umd.edu) - University of Maryland;
Jianjun Hao, (haojianj@msu.edu) - Michigan State University;
Linda Kinkel, (kinkel@umn.edu) - University of Minnesota;
Jenifer McBeath, (jhmcbeath@alaska.edu) - University of Alaska- Fairbanks;
Jennifer Parke, (jennifer.parke@oregonstate.edu) - Oregon State University;
Tim Paulitz, (paulitz@wsu.edu) USDA/ARS-WA;
Antoon Ploeg, (antoon.ploeg@ucr.edu) - University of California- Riverside;
Michael Stanghellini, (michael.stanghellini@ucr.edu) - University of California- Riverside;
James White, (white@rci.rutgers.edu) - Rutgers University;
Gary Yuen, (guen@unl.edu) - University of Nebraska

Guest

Jim Downer - UCCE, Ventura County

Brief Summary of Minutes

Minutes

2013 Meeting of the Multistate Project W3147

December 6, 2013

Mission Inn, San Diego Room

Riverside, CA

Gary Yuen, Chair

Ole Becker, Secretary

James Borneman, local arrangements

Members in attendance:

Ole Becker (CA), James Borneman (CA), Darin Eastburn (IL), Kathryne Everts (MD), Jianjun Hao (MI), Linda Kinkel (MN), Jenifer McBeath (AK), Jennifer Parke (OR), Tim Paulitz (WA), Antoon Ploeg (CA), Michael Stanghellini (CA), James White (NJ), Gary Yuen (NE)

Guest: Jim Downer (UCCE, Ventura County)

Minutes

The meeting began at 8:30 AM with the chairs welcome and self-introduction of attendees.

M. Kahn (WA, Administrative Advisor) was not able to attend this meeting; T. Paulitz related news concerning reporting changes to the members. REEport is now NIFAs singular grant and formula project reporting system that replaced the former CRIS web forms system.

J. Parke was unanimously elected to be secretary for 2014. O. Becker will be the 2014 chair. After a discussion concerning possible alternative meeting locations, Riverside, CA was again chosen for the 2014 meeting. D. Eastburn volunteered to run a Doodle poll to determine a suitable date.

Progress reports started with J. McBeath who reviewed her research on Trichoderma atroviride, including its use as the active ingredient in the commercial product Plant Helper.

M. Stanghellini reported on a vine-decline of mature watermelons caused by Olpidium bornavanus.

A. Ploeg described responses of root-knot nematode-resistant pepper cultivars obtained from a southeastern USDA group (Thies) when challenged with a southern California root-knot nematode strain.

J. Downer reported on the influence of compost amendments and the process of incorporation on soil microbial populations and plant pathogens.

J. Borneman gave an update on recent findings in a collaborative project with O. Becker's group at UCR on Dactylella oviparasitica, a fungal parasite of female sedentary Heterodera cyst nematodes.

J. White discussed projects concerning microbial endophytes. In vanilla orchids endophytic bacterial biofilms fixed nitrogen.

D. Eastburn reported on a project attempting to suppress soybean diseases through cover cropping. He also summarized his group's findings on recently discovered double-stranded RNA mycoviruses of Fusarium virguliforme.

J. Hao discussed optimization work on the biocontrol agent Bacillus amyloliquifaciens BAC03. In addition he gave an overview of his new responsibilities at the University of Maine.

K. Everts reported on the use of various green manure cover crops against Fusarium wilt (F. oyxsporum f. sp. nivium) in watermelon production.

L. Kinkel discussed her research focus on antagonistic bacterial populations in native prairie and agricultural soils. Certain plant species appear to provide nutrients that enrich their rhizosphere with antibiotic-producing microbes, creating a protective environment against soilborne pathogens.

G. Yuen reviewed his research on the biocontrol bacterium Lysobacter enzymogenes. In addition, he suggested the W3147 members should prepare outreach publications and presentations for the general audience. Others proposed lab exercises or instructional short videos. The APSnet Education Center was mentioned for viewing examples and as a potential peer-reviewed, open access deposit site (http://www.apsnet.org/EDCENTER/Pages/default.aspx).

J. Parke reported on Phytophthora communities in plant nurseries and her group's systems approach for managing Phytophthora diseases.

T. Paulitz gave an overview of several WA projects including natural suppression of Rhizoctonia patch disease in wheat. He also discussed the occurrence of phenazine vs. phloroglucinol-producing bacteria in dry and irrigated soils.

Prior to adjourning at 5 pm, the members expressed their thanks to J. Borneman for his excellent job in making local arrangements.

Submitted: O. Becker

Accomplishments

Objective 1. To identify and characterize new biological agents, naturally suppressive soils, cultural practices, and organic amendments that provide control of diseases caused by soilborne plant pathogens. AK- A mycovirus was found from a biocontrol product from Japan. The mycovirus was found to be an isometric dsRNA virus. Infected Trichoderma sp. typically produces fewer conidia, loss of pigmentation, rampant mycelia growth and reduced biocontrol activities. Using a detached leaf test, virus-infested Trichoderma sp. showed reduced biocontrol activities against Sclerotinia sclerotiorum. Mycovirus also affects gene expressions of chitinase, glucanase, and proteinase, which are extracellular enzymes related to biological control. Also it was found to be possible to transmit this mycovirus from diseased Trichoderma to a previously healthy Fusarium sp. CA-R- Root-associated bacteria, fungi and stramenopiles associated with peach replant disease symptoms at a field location in California's Central Valley were identified using culture and culture-independent analyses. Among the 60 most abundant bacterial operational taxonomic units, 27 showed significant negative correlation with peach shoot weights. The most abundant stramenopiles with suppressive potential were Pythium vexans, and P. violae. It was determined that Olpidium bornovanus was the cause of vine decline of mature watermelon plants and that infection and disease severity was related to a daily irrigation regime. In a third study, various aspects of the host-microbe interactions between the fungus Dactylella oviparasitica and the plant-parasitic nematode Heterodera schachtii were investigated toward the goal of developing a more effective tool for making sugar beet planting decisions. Parasitism of the nematode by the fungus was studied using both Arabidopsis thaliana and cabbage as host plants in gnotobiotic agar culture. The number of females with eggs was reduced by more than 95% and the number of eggs per female by almost 60% as compared to females developing on plates without the fungus. Viable eggs were not susceptible to parasitism while more than 90% of heat or cold killed eggs were rendered susceptible. NM- A study was initiated to evaluate the efficacy of biorational products on soilborne pathogens. In the first phase of the study, selected biorational products which included formulations containing bacterial and fungal microorganisms, and botanical extracts were tested in vitro using a modified agar well diffusion assay for efficacy against three soilborne pathogens of Valencia peanut, Sclerotinia sclerotiorum (causal agent of Sclerotinia blight), Sclerotium rolfsii (causal agent of stem rot and pod rot), and Rhizoctonia solani (causal agent of pod rot). Detached leaflets of Valencia peanut were treated by dipping in each formulation, and then inoculated with S. sclerotiorum. Very little inhibition was displayed on agar well diffusion assay, with the greatest growth inhibition exhibited by a formulation containing Bacillus subtilis QST713. Lesion area on detached Valencia peanut leaflets inoculated with S. sclerotiorum was variable among formulations, and none prevented leaflet infection. Further research is needed on evaluating additional biorational products in order to identify formulations efficacious against soilborne fungal pathogens of peanut and other crops. Based on observations by some chile pepper producers, the incidence of Phytophthora blight (Phytophthora capsici) appears to be reduced in field areas where algal growth is widely present. A study was conducted to determine the effect of the fresh water algae Chlorella sorokiniana on P. capsici. Generally, sporangia production was initiated earlier in algal cell suspension than in water, and production of sporangia in algal cell suspension was as high as or higher than in water. Symptoms of infection typically appeared first in plants treated with algal cell suspension. Results suggest that the green algae C. sorokiniana enhances sporulation by P. capsici and is unlikely to prevent plant infection. NY- Effects of Tillage Systems on Root Rot Severity and Yield of Snap Beans: This tillage trial was established in the experimental root rot field at the Vegetable Research Farm of the NYSAES, Cornell University in Geneva, NY. This field has been in continuous bean production for about 20 years and is heavily infested with the bean root rot pathogens Fusarium solani f. sp. phaseoli, Pythium ultimum, Thielaviopsis basicola and Rhizoctonia solani. On May 10, the grain rye cover crop in the field was killed with Round-up and the three tillage systems (conventional, ridge-till, and zone-till) were prepared the following week. On June 27, the snap bean variety "Caprice" was planted in all the tillage plots using a 2-row Monosem planter that banded 300 lbs./A of a complete fertilizer (10-10-10, NPK). Each tillage system was represented with 20 rows of beans that were 390 ft. long. All plots were sprayed with the herbicides Dual Magnum (1.5 pt./A) and Basagran (1.5 pt./A) on June 27 and August 2, respectively. Stand establishment and root rot severity on randomly collected plants were recorded on August 5. Plots were machine harvested on August 28. Results obtained are summarized in Table 1. Stand establishment was similar among the tillage systems. Root rot severity ratings was significantly higher on roots of plants growing in the conventional tillage system as compared to ratings of plants growing in the zone-till or the ridge-till systems. Also, plant growths at 39 days after planting and pod weight at harvest time were significantly lower for plants growing in the conventionally tilled plots. In addition, soil surface crusting was worst in plots under the conventional tillage. Detection and identification of plant pathogens. A membrane-based multi-pathogen detection macroarray has been developed. The array can detect over 40 fungal and oomycete plant pathogens from plant tissue and soil. This array can now be used with either chemiluminescent or chromogenic-based assay. In 2013 we continued and have nearly completed two projects, the first is to detect pathogens in irrigation water, and the second is to detect and identify pathogens in the rhizosphere following various mixed-species green manure treatments. We tested 20 irrigation sites across NY and identified over 20 species of Phytophthora and Pythium. We are currently performing RE-EM (random effects estimation method) statistics to determine if correlations exist between species identified and site location, pH, turbidity, or water temperature. These data will be submitted for publication in early 2014. For the mixed-species green manure treatments, we are collaborating with Brian McSpadden-Gardener (Ohio State University) and Kate Everts (U Maryland). We had 5 green manure treatments and an untreated control in New York. Tomato transplants were planted into each plot. Rhizosphere samples were taken from each plot and were analyzed. Disease ratings for early blight, Septoria, and Phytophthora blight were also taken. Because of variable results observed in 2010 and 2011, the experiment was repeated again in 2012. The data were analyzed in 2013 by my graduate student Carly Summers and results from three states (NY, MD and OH) have been accepted for publication (with revisions) in Applied Soil Ecology. Samples from these plots were also used to identify beneficial microbes. A Mitsuaria species was identified that has anti-microbial properties, but is not phytotoxic. This bacterium will be the focus of continued study in McSpadden-Gardeners lab. WA- A study of microbial communities associated with the natural long-term suppression of Rhizoctonia bare patch was conducted. Two taxonomic groups of bacteria were associated with the rhizosphere from diseased plants in the center of the patches- Oxalobacteriaceae - Massillia, Herbaspirillum, Duganella; and Sphingobacteria - Chyseobacterium, Pedobacter, Chitinophagaceae. Only two taxa were associated with recovered patches - Gemmatimonas and Acidobacteria GP-3. This shift in the makeup of the bacterial community was duplicated in greenhouse cycling experiments. Kochs postulates were performed on isolates of Chyseobacterium, which were isolated from the suppressive rhizosphere and reduced Rhizoctonia disease in greenhouse tests. Comparative genomics and bioinformatics continue on 11 new strains of Pseudomonas having suppressive activity against two or more soilborne fungal pathogens and plant-parasitic nematodes. Genome sequencing of an additional 22 strains is in progress. An automated annotation pipeline has been redesigned, and annotation of one strain has been completed. Loci encoding low molecular weight metabolites and DNA unique to each strain are the current focus of the project. A field study on managing Fusarium wilt in spinach seed crops evaluated the use of 2 years of agricultural limestone amendment to soil with or without biosolids compost applied to the soil within 2 weeks of planting a spinach seed crop trial, and with or without the fungicide prothioconazole applied 3 times. The biosolids compost increased marketable seed yield by 19, 29, and 20% compared to control plots of susceptible, moderate, and partially resistant female lines, respectively. Prothioconazole increased marketable seed yields by 19, 6, and 16% compared to control plots of susceptible, moderate, and resistant female lines, respectively. The trial demonstrated that growers can reduce the rotation interval between spinach seed crops from the current 8-15 years (depending on susceptibility of the parent lines to Fusarium wilt) to as little as 7 years by utilizing both limestone and compost to suppress Fusarium wilt. This could potentially double the carrying capacity for spinach seed production in the USA, as the coastal Pacific Northwest is the only region of the USA with suitable climatic conditions for production of spinach seed, despite the highly conducive nature of the acidic soils in this region to spinach Fusarium wilt. Objective 2. To understand how microbial populations and microbial gene expression are regulated by the biological (plants and microbes) and physical environment and how they influence disease. AK- Trichoderma atroviride is a versatile, aggressive hyperparasite found in Alaska with activities against diverse plant pathogenic fungi under a wide range of environmental conditions. Antagonistic assays have shown T. atroviride to be an effective biocontrol agent against Botrytis cinerea, Phytophthora erythroseptica, P. infestans and Rhizoctonia solani. Among the many extracellular enzymes produced by T. atroviride during its interaction with plant pathogens, a proteinase showed strong antifungal activity, even at low temperatures. To fully understand the role of this proteinase on Trichoderma biocontrol, the Trichoderma genome was studied by using partial aminio acid sequence of the proteinase to find that it matches the gene sequence of a hypothetical protein (GenBank No EHK47941). Then 1500 bp of the upstream and downstream sequences of this gene were amplified by PCR and inserted into the plasmid P3 (containing hygromycin (HYG) resistant gene), respectively. Using PCR to obtain the construct which contains the upstream sequence of the proteinase, the HYG gene sequence and downstream sequence of the proteinase and at last the construct were transferred into the protoplast of T. atroviride 901 using polyethylene glycol (PEG)-mediated transformation method. The mutants were selected by single spore isolation on potato dextrose agar (PDA) supplemented with 200 ¼g/ml hygromycin B and detected by PCR and Southern blot. Two proteinase knockout strains and a mock strain were selected for further tests. The test results showed that the conidia of proteinase mutants mature later than the wild type on PDA; mutants are less active against Sclerotinia sclerotiorum in the confronting test on PDA and less antifungal activity on detached tomato leaves against S. sclerotiorum. NM- Pathogenicity of Sclerotinia sclerotiorum on Valencia peanut was examined in relation to mycelium pigmentation and oxalic production. The following are the findings of the study: 1) there is no relationship between mycelium pigmentation and the ability of S. sclerotiorum to infect peanut plants; 2) oxalic acid production is associated with peanut infection by S. sclerotiorum; and 3) sugars such as glucose play a role in the production of oxalic acid and therefore in the pathogenicity of S. sclerotiorum. The finding of this work is useful in terms of disease control, particularly with a focus on identifying sugars that are associated with oxalic acid production. Suppression of oxalic acid production through manipulation of sugars may render S. sclerotiorum less pathogenic on peanut and other plant hosts. Research conducted on seed transmission of Verticillium dahliae in chile pepper showed that seed infection does take place in chile pepper. On-going research is aimed at determining if seed transmission (movement of the pathogen from the seed into the growing plant) takes place in chile. Seed transmission represents a pathway of pathogen survival and dispersal, and therefore has epidemiological and economic implications. Research was completed on the interaction between the fungal microorganism Verticillium dahliae and the root knot nematode Meloidogyne incognita on chile pepper and weeds. Results showed that V. dahliae and M. incognita caused greater damage to chile pepper than to the weeds. The implication of this finding for chile producers is that weed control is crucial in order to minimize the perpetuation of the pathogens. NE- Previous research on Lysobacter enzymogenes strain C3, a biocontrol agent of fungal plant pathogens, demonstrated production of lytic enzymes (chitinases and glucanases) and HSAF (a family of macrocyclic lactams including dihydromaltophilin) to be an important biocontrol mechanisms. PilG a response regulator protein involved in two-component signal transduction was found to negatively regulate the production of lytic enzymes and HSAF while simultaneously up-regulating gliding motility via type 4 pili. This is the first discover of PilG being involved in regulation of motility and production of antimicrobial metabolites in a biocontrol bacterium. In a separate study, strains of L. enzymogenes isolated from soils and plants were compared for their capacity to colony the phyllosphere of various plant species. The strains were found to be similar in establishing population within the leaves of common bean, swiss chard, cabbage and tall fescue, but none could establish epiphytically on or endophytically in leaves of green onion. These results establish the endophytic habit to be common among strains of L. enzymogenes but that mode of existence is plant species dependent. NJ Research focused on understanding the role of microbial endophytes in protecting plants from biotic (diseases and pests) and abiotic stresses. This year research was continued to develop an understanding of the biology of fungal Epichloë endophytes of grasses, specifically the modes of reproduction and dessimination of endophytes and how that relates to their classification and affects on plant resistance biotic and abiotic stress. A book chapter in print (Meyer, Torres and White, 2013) and two articles, now In Press in Mycologia, are the result of this research. On a parallel track, bacterial endophytes in vanilla orchids (Vanilla phaeantha and V. planifolia x pompona) and blue agave (Agave tequilana) were examined. In vanilla orchid vines we found that the bacterial endophyte, Bacillus amyloliquefaciens, contributes to defense of plants from pathogens by production of antifungal lipopeptides. In addition, the bacterium fixes nitrogen in the growing tissues of vines, thus contributing to the nutritional status of vanilla plants (Manuscript in review). This research may lead to new ways that vanilla plants may be protected from the fungal disease epidemics that are currently threatening vanilla production worldwide. In another project focused a bacterial endophyte, Bacillus tequilensis, of blue agave, we demonstrated that bacteria may become inter- and intra-cellular in plants where they are degraded through an oxidative mechanism and provide nitrogen that may support growth of the plant in its desert habitat. The presence of this endophyte in agave plants very likely enhances resistance of plants to both biotic and abiotic stress through enhancing nutritional status and health of the plant. Research on bacterial endophytes of several additional horticultural crops and corn are ongoing. WA- The biogeography and phylogenetic diversity of phenanzine producing strains of Pseudomonas on wheat roots in the dryland Pacific Northwest were investigated. Phenazine is an antifungal compound produced by Pseudomonas that suppresses disease. From sequencing of a number of genes, four diverse groups were identified - P. orientalis, P. synxantha, and two new species - P. aridus and P. cerealis. Under irrigated conditions in the same area, the community is dominated by phlorglucinol producers. There is also a strong negative correlation between precipitation and the dominance of phenazine producers, but a positive correlation with phloroglucinol producers. A three-year field study has been completed at Lind, WA with irrigated and dryland plots side-by-side. The populations of phenazine producers and the level of phenazine in the rhizosphere are maintained at higher levels over the season in the dryland plots compared to the irrigated plots. To understand how these bacteria can survive and thrive in the driest wheat growing areas, microcosm experiments are being conducted to look at the role of phenazine and biofilms under dry conditions. Objective 3. To implement sustainable management strategies for soilborne pathogens that are biologically based and compatible with soil health management practices. CA-R- We evaluated biologicial and biorational nematicides for their efficacy in protecting carrots and processing tomatoes in root-knot nematode infested field trials. Nematicidal seed coatings with abamectin as the active ingredient achieved remarkable early season protection against root-knot nematodes in two carrot field trials. Soil treatments with bionematicides NemaQ, Ecozin, Sesamin EC, Nortica and Actinovate showed no significant efficacy against Meloidogyne incognita in tomato trials. MD- Fusarium wilt of watermelon, caused by Fusarium oxysporum f. sp. niveum (FON) is an important disease of watermelons worldwide, and is re-emerging in the mid-Atlantic region. In Maryland and Delaware, the inoculum density of FON is high as a result of a long history of watermelon production. In previous work, soil organic amendments were evaluated and a crop of Vicia villosa (hairy vetch) that was planted in the fall, and tilled into the soil in the spring as a green manure, suppressed Fusarium wilt. However growers have not adopted this production practice due to lack of information on the mechanism of suppression, and because of concerns about persistence of V. villosa seed in fields. To evaluate whether the suppression was general or specific (that is due to overall increase in microbial population or due to the increase in one or a few species), field trials were conducted over three years. In addition, the cover crops Trifolium incarnatum, Secale cereale and Brassica juncea were evaluated for suppression. In our trials, both T. incarnatum and V. villosa suppressed Fusarium wilt in fields where disease pressure was moderate to high, although the magnitude of the suppression was greater for V. villosa. Immediately preceding and following cover crop tillage, the soil respiration (micrograms of soil CO2 flux) was measured. The CO2 flux in T. incarnatum plots was highest among cover crops in 2009, and was elevated even before tillage. In 2010 and 2011, the CO2 flux in V. villosa plots was significantly higher than bare ground, although T. incarnatum plots also had higher CO2 flux than bare ground in most locations. Arbuscular mycorrhizae (AM) colonization of the watermelon crop also differed following the cover crop treatments. When watermelon followed a V. villosa cover crop, AM colonization was significantly higher than where watermelon followed other cover crops or bare ground at one location. In another location, watermelon following V. villosa and T. incarnatum both had significantly greater AM colonization than watermelons following other cover crops. NY- Assessing the Reaction of Selected Pea Varieties Under Severe Root Rot Pressure: At the request of and with financial support by pea growers in New York, field and greenhouse trials were conducted to determine the reaction of current and promising pea varieties to soilborne pathogens, specially Fusarium solani f. sp. pisi. Eleven varieties were planted on May 2, 2013 in a commercial pea field in western NY with a recent history of severe incidence and damage by Fusarium cortical root rot. All land preparation and various inputs were according to commercial production guidelines and made by the collaborating grower. Commercially-treated seeds of the selected varieties were planted with a small drill and each plot consisted of 7 rows, 33 ft. long and there were 3 replications/variety. Stand establishment and root rot severity were determined on June 18. The vigor of the varieties was assessed on June 25 and the varieties were harvested from June 26 to July 9; depending on their maturity. Data obtained from this trial are summarized in Table 2. There were differences among the pea varieties tested in stand establishment, vigor, root rot severity and fresh weight of the pods. Also, the lesion nematode was recovered from the roots of all the varieties, but the numbers of nematodes recovered were not statistically significant. The lesion nematode is known to be a predisposing agent in several root disease complexes, thus the distribution and association of this nematode among root rot pea fields needs further study. The long-term soil health site at the Gates Farm near Geneva (14 acres) was maintained for another cycle of evaluation in collaboration with the Soil Health Program Work Team at Cornell. The site was established in 2003 and consists of 72 plots (18 treatments with 4 replications). The treatments include three tillage systems (no-till, strip-till, and conventional tillage), three cover crops (rye grain, hairy vetch, and no cover/fallow) and two rotations (one heavy with vegetables, whereas the other includes grain and forage crops and less vegetables). Root health, soil health, and yield data have been collected annually. Results of the root health assessment (soil bioassay with beans in the greenhouse) showed that root rot severity was reduced by the not-till and strip-till tillage and also the diversified crop rotation, but not by the cover crop treatments. Utilizing green manures to reduce the severity of Phytophthora capsici on tomato. In 2009, the Smart lab started a project (in collaboration with the McSpadden-Gardener and Everts labs) to identify green-manure cover crops that are effective in reducing the incidence of Phytophthora blight on tomato. These experiments were completed in 2012, and no reduction in Phytophthora blight was observed. These data are in a second publication submitted to Applied Soil Ecology. WA- Based upon research from the program of Mark Mazzola, a Brassicaceae seed meal formulation was commercialized and Mazzola is now in the process of seeking approval for use as a bio-pesticide (Farm Fuels Inc., Santa Cruz, CA). Wheat harboring new sources of genetic resistance are being characterized in field and greenhouse screens. Several promising lines are being advanced and used to construct populations for genetic mapping of resistance loci. Demonstration of how application of agricultural limestone for several years preceding spinach seed crops can suppress spinach Fusarium wilt has led to widespread and routine use of limestone amendment at recommended rates (2 tons/acre) by spinach seed growers in western Washington and Oregon to reduce the conduciveness of soils in this region to Fusarium wilt. This, together with evaluating the level of risk of spinach Fusarium wilt using a soil bioassay developed as part of a PhD students research project in du Toits program, have enabled growers to reduce the rotation interval between spinach seed crops by as much as 50% without incurring major losses to Fusarium wilt. Objective 4. Provide outreach, education, extension and technology transfer to our clients and stakeholders- growers, biocontrol industry, graduate and undergraduate students, K-12 students and other scientists. AK- McBeath and her lab worked closely with collaborators and users of Plant Helper, a plant-growth promoter product based on Trichoderma atroviride, in the U.S., Korea and China. Plant Helper is currently being manufactured and distributed by AmPac Biotech, a commercial company based in Fresno, CA. CA-R- M. Stanghellini taught the Introductory course in Plant Pathology to 63 students. Many examples of root diseases presented are those from his own research as well as research reported by members of W2147 (W3147). MD- K. Everts mentored a doctoral student, Jennifer Himmelstein, through completion of her doctoral dissertation, "Mechanisms of disease suppression by a hairy vetch (Vicia villosa) cover crop on Fusarium wilt of watermelon and the efficacy of the biocontrol Actinovate." NE- G. Yuen at University of Nebraska-Lincoln taught a new distance-delivered course Plant Pathology Principles and Applications to 18 graduate students and professions located throughout the nation involved in plant health disciplines. Yuen also taught Introductory Plant Pathology to nearly 70 undergraduate students. In both courses, biological control through the applied or indigeneous microbes was presented as critical component of integrated disease management, and examples of research and implementation from W3147 members were used to illustrate these facets. In addition, Yuen mentored 3 graduate students and 2 international interns in research projects related to biological control. NY- Outreach Activities on Sustainable Management of Root Diseases and Soil Health: Two, full-day workshops were presented by G. Abawi on January 28 and March 20, 2013 in Hershey, PA and Geneva, NY; respectively. These workshops are in collaboration with Beth Gugino (Penn. State University) and Jim LaMondia (Connecticut Agric. Exp. Station) and are funded by the NE-SARE Program. The illustrated and participatory workshops dealt with the diagnosis, assessment and management of soilborne plant pathogens in vegetable production systems. A total of 70 participants attended the two workshops and included vegetable growers, extension educators, crop consultants and other agricultural service providers. Also, Abawi made a presentation at the Empire State Fruit and Vegetable Expo in Syracuse, NY on January 23, 2013 (75 in attendance) on diseases of carrots and table beets and their management. In addition, Abawi gave a talk at the Mid-Atlantic Fruit and Vegetable Conference in Hershey, PA on the bloat nematode on garlic and related crops (January 30, 2013 100 in attendance). He also participated in two garlic training workshops held in Geneva and Albany, NY on March 22 and April 10, 2013; respectively (68 participants). Abawi also made a presentation at the Dry Bean Field Day on September 26, 2013 with 25 in attendance and attended and made presentations at the pea, carrot, and table beet Commodity Advisory Committee meetings on December 3, 2013. Furthermore, Abawi made numerous visits to commercial fields of carrots, beets, peas, and onions with extension vegetable educators diagnosing disease problems and talking to local growers. Disease management strategies for Phytophthora capsici In 2013, C. Smart gave 8 talks to growers, extension educators and industry representatives on strategies to control Phytophthora blight. These included talks at the NY state fruit and veg expo, talks at winter grower meetings in western and eastern NY, and summer twilight meetings. Additionally, Smart presented a webinar during the winter of 2013 to beginning vegetable growers. Undergraduate research experience. The Plant Pathology and Plant-Microbe Biology Department on the Geneva Campus of Cornell University established a summer scholars program to increase the involvement of undergraduate researchers in applied agricultural sciences. Smart is the director of this program for all 4 departments on the campus. In 2013, 27 students presented posters at the end of the program. Each summer, several students are involved with projects that are part of the W2147 multi-state project. During the summer of 2013, two students in the Smart lab were working on Phytophthora capsici the first looking at interactions between the pathogen and resistant vs susceptible pepper hosts and the student worked on the population biology and evolution of the pathogen. Additionally, an undergraduate student in the Abawi lab worked on nematode problems in garlic and other vegetables. Outreach to K-12 students. W3127 members at Cornell University continued their outreach program to third-grade students in the Geneva City School District (Geneva, NY). Part of this outreach included a summer science camp, where students study different aspects of food production utilizing a garden that they plant at their school. One week of the 5-week program focused on the importance of healthy soil to producing healthy vegetables.

Publications

Refereed Publications and Abstracts Abawi. G. S., Porch, T. C., and Kelly, J. D. 2013. Field evaluation of promising breeding lines and varieties of common bean for tolerance to soilborne pathogens. Poster presented at the APS-MSA meeting held in Austin, Tx during August 10-14, 2013. <a href="http://www.apsnet.org/meetings/Documents/2013_meeting_Abstracts">http://www.apsnet.org/meetings/Documents/2013_meeting_Abstracts </a> Alcala, A.C., du Toit, L.J., Derie, M.L., Holmes, B., Coffman, G., Gatch, E.W., and Porter, L.D. 2013. Evaluation of priming and Nordox seed treatment for controlling damping-off in organic pea crops in central Washington, 2012. Plant Disease Management Reports 7:ST001. Alcala, A.C., Porter, L.D., Derie, M.L., Holmes, B., Coffman, G., and du Toit, L.J. 2013. Evaluation of seed treatments and priming for controlling damping-off in organic pea crops in the semi-arid Columbia Basin and maritime Skagit Valley of Washington, 2012. Plant Disease Management Reports 7:ST002. Agostini, A., Johnson, D. A., Hulbert, S., Demoz, B., Fernando, W. G. D., and Paulitz, T. C. 2013. First report of blackleg caused by Leptosphaeria maculans on canola in Idaho. Plant Disease 97(6):842. Al-Hammouri, A., Lindeman, W., Sanogo, S., Thomas, S., and Steiner, S. 2013. Interaction between Rhizoctonia solani and Meloidogyne incognita on chile pepper in soil infested simultaneously with both plant pathogens. Canadian Journal of Plant Science 93: 67-69. Babiker, E. M., Hulbert, S. H., and Paulitz, T. C. 2012. Hyaloperonospora camelinae on Camelina sativa in Washington State: Detection, seed transmission, and chemical control. Plant Disease 96(8):1670-1674. Babiker, E. M., Hulbert, S. H., Schroeder, K. L., and Paulitz, T. C. 2013. Evaluation of Brassica species for resistance to Rhizoctonia solani and binucleate Rhizoctonia (Ceratobasidum spp.) under controlled environment conditions. European Journal of Plant Pathology DOI 10.1007/s10658-013-0205-8. Becker, J. O., H. Witte, J. Smith Becker, G. W. Douhan, J. P. Vogel, and A. Ploeg 2012. Brachypodium distachyon: A model plant to study root-knot nematode - Pooideae interactions. J. Nematology 44: 452. Becker, J.O., and D. Burger 2012. Calorespiromentric analysis for optimizing seed coatings. J. Nematology 44: 451. Bihn, E.A., Smart, C.D., Hoepting, C.A., and Worobo, R.R. (2013) Use of surface water in the production of fresh fruits and vegetables: A survey of fresh produce growers and their water management practices. Food Protection Trends 33:307-314. Cai, G., Restrepo, S., Myers, K.L., Zuluaga, P., Danies, G. Smart, C.D. and Fry, W.E. (2013) Gene profiling in partially resistant and susceptible near-isogenic tomatoes in response to late blight in the field. Molecular Plant Pathology 14:171-184. Danies, G., Martin, F., Myers, K., Cooke, D.E., Smart, C.D., Seaman, A. and Fry, W.E. (2013) Investigation of a population of Phytophthora infestans in and near central New York in 2011. Phytopathology 103:S2.33 Dunn, A.R., Fry, B.A., Lee, T.Y., Conley, K.D., Balaji, V., Fry, W.E., McLeod, A., and Smart, C.D. (2013) Transformation of Phytophthora capsici with genes for green and red fluorescent protein for use in visualizing plant-pathogen interactions. Australasian Plant Pathology 42:583-593. Dunn, A.R., Lange, H.W., and Smart, C.D. (2013) Evaluation of commercial bell pepper cultivars for tolerance to Phytophthora blight. Plant Health Progress in press Dunn, A.R. and Smart, C.D. (2013) Attachment and germination of Phytophthora capsici zoospores on roots of susceptible and resistant peppers. Phytopathology 103:S2.37 Dunn, A.R., Wyatt, L.E., Mazourek, M., Reiners, S., and Smart, C.D. (2013) Performance and tolerance to Phytophthora blight of bell pepper varieties. HortTechnology 23:382-390. Fang, H., Zhou, H., Sanogo, S., Flynn, R. P., Gore, M., Hughs, S. E., Jones, D. C., and Zhang, J. 2013. Development of sequence tagged site (STS) markers for Verticillium wilt resistance in cotton based on RGA-AFLP analysis. Beltwide Cotton Conference, San Antonio, TX, January, 2013. Fry, W.E., McGrath, M.T., Seaman, A., Zitter, T.A., McLeod, A., Danies, G., Small, I.M., Myers, K., Everts, K., Gevens, A.J., Gugino, B.K., Johnson, S.B., Judelson, H., Ristaino, J., Roberts, P., Secor, G., Seebold, K., Snover-Clift, K., Wyenandt, A., Grunwald, N.J., and Smart, C.D. (2013) The 2009 late blight pandemic in Eastern USA causes and results. Plant Disease 97: 296-306. Handiseni, M., Brown, J., Zemetra, R., and Mazzola, M. 2012. Use of Brassicaceous seed meals to improve seedling emergence of tomato and Pepper in Pythium ultimum infested soils. Archives of Phytopathology and Plant Protection 45:1204-1209. Handiseni, M., Brown, J., Zemetra, R., and Mazzola, M. 2013. Effect of Brassicaceae seed meals with different glucosinolate profiles on Rhizoctonia root rot of wheat. Crop Protection 48:1-5. Hao, J. J. and Subbarao, K. V. 2013. Distribution of lettuce big-vein under three irrigation systems. Plant Disease. DOI: 10.1094/PDIS-04-13-0410-RE. Holdsworth, W.L., Summers, C.F., Glos, M., Smart, C.D., and Mazourek, M. (2014) Development of downy mildew-resistant cucumbers for late-season production in the northeast. HortScience in press. Iglesias-Garcia, A. M., Villarroel-Zeballos, M. I., Feng, C., du Toit, L. J., and Correll, J. C. 2013. Pathogenicity, virulence, and vegetative compatibility grouping of Verticillium isolates from spinach seed. Plant Disease 97:1457-1469. Jones, L.A., Worobo, R.W., and Smart, C.D. (2013) Ultraviolet treatment of surface irrigation water for improved plant health and food safety. Phytopathology 103:S2.69 Jones, L.A., Worobo, R.W. and Smart, C.D. (2014) Ultraviolet light inactivation of human and plant pathogens in unfiltered surface irrigation water. Applied and Environmental Microbiology in press. Kandel, S. L., Smiley, R. W., Garland-Campbell, K., Elling, A. A., Abatzoglou, J., Huggins, D., Rupp, R. and Paulitz, T. C. 2013. Relationship between climatic factors and distribution of Pratylenchus spp. in the dryland wheat production areas of Eastern Washington. Plant Disease: 97:1448-1456. Kundu, S., Sanogo, S., Schutte, B., and Cooke, P. H. 2013. Peduncular and seed infection in chile pepper by the plant pathogenic fungus Verticillium dahliae. APS Joint Caribbean and Pacific Division Annual Meeting; Tucson, Arizona, June 17-19, 2013. Lange, H.W. and Smart, C.D. (2013) Evaluation of the control of black rot in cabbage following treatments to transplants in the greenhouse and field. Phytopathology 103: S2.76 Leuchtmann A, Bacon CW, Schardl CL, White JF Jr, Tadych M. (In Press). Realignment of Neotyphodium species with genus Epichloë. Mycologia (Accepted October, 2013). Liu, H. W., Luo, L. X., Li, J. Q., Liu, P. F., Chen, X. Y., and Hao, J. J. 2013. Pollen and seed transmission of Cucumber Green Mottle Mosaic Virus in cucumber. Plant Pathology 15:376-383. Lu, X. H., Jiang, H. H., and Hao, J. J. 2013. First report of Pythium recalcitrans causing carrot cavity spot. Plant Disease 97:991. Lujan, P., Dungan, B., Schaub, T., Randall, J., Puppala, N. Idowu, J., and Sanogo, S. 2013. The role of carbon sources in relation to pathogenicity of Sclerotinia sclerotiorum on Valencia peanut. APS Joint Caribbean and Pacific Division Annual Meeting; Tucson, Arizona, June 17-19, 2013. Luo, L., S. R. Yates, D. J. Ashworth, A.M. Ibekwe, O. Becker, S.R. Lee, and R. Xuan 2012. The effects of soil solarization and MeI chemigation on soil bio-chemical properties and nematode survival. ASA, CSSA and SSSA Annual Meetings (Cincinnati, OH- Oct. 21 - Oct. 24, 2012). <a href="http://scisoc.confex.com/crops/2012am/webprogram/Paper75418.html">http://scisoc.confex.com/crops/2012am/webprogram/Paper75418.html </a> Matsui, M., H. Honjo, J. O. Becker, and R. Fukui 2013. Temperature-dependent effects of soil amendment with crop residues on suppression of Rhizoctonia damping-off of sugar beet. Plant and Soil 348:467-477. Mavrodi, D. V., Mavrodi, O. V., De La Fuente, L., Landa, B. B., Thomashow, L. S., and Weller, D. M. 2013. Management of plant pathogens and pests using microbial biological control agents. In Plant Pathology Concepts and Laboratory Exercises, 3rd ed. CRC Press (Taylor and Francis) USA. Mavrodi, D. V., Parejko, J. A., Mavrodi, O. V., Kwak, Y. S., Weller, D. M., Blankenfeldt, W., and Thomashow, L. S. 2013. Recent insights into the diversity, frequency and ecological roles of phenazines in fluorescent Pseudomonas spp. Environmental. Microbiology 15(3):675-686. Mazzola, M., Reardon, C. L., and Brown, J. 2012. Initial species composition and brassicaceae seed meal type influence extent of Pythium-induced plant growth suppression. Soil Biology & Biochemistry 48:20-27. Mazzola, M., and Manici, L. M. 2012. Apple replant disease: Role of microbial ecology in cause and control. Annual Review of Phytopathology 50:45-65. Mazzola, M., and Strauss, S. L. 2013. Resilience of orchard replant soils to pathogen re-infestation in response to Brassicaceae seed meal amendment. Aspects of Applied Biology 119:69-77. Meng, Q., Hanson, L. E., Douches, D., and Hao, J. J. 2013. Managing common scab caused by Streptomyces scabies using Bacillus amyloliquefaciens BAC03 and other biomaterials. Biological Control 67:373-379. Meyer WA, Torres MS, White JF, Jr. 2013. Biology and applications of fungal endophytes in turfgrasses. Chapter 20, pp 713-731, Stier JC, Horgan BP, Bonos SA (Eds.), Turfgrass: Biology, Use, and Management. Agronomy Monograph 56. American Agronomy Society, Madison, WI. ISSN 0065-4663. Ming Li, Dechun Wang. 2013. Phytophthora root rot resistance in soybean E00003. Crop Science. In print. Okubara, P. A., Harrison, L. A., Gatch, E., Vandemark, G., Schroeder, K. L., and du Toit, L. 2013. A TaqMan real-time PCR assay for Fusarium oxysporum f. sp. spinaciae. Plant Disease 97(7):927-937. Parejko, J. A., Mavrodi, D. M., Mavrodi, O. V., Weller, D. M., and Thomashow, L. S. 2013. Taxonomy and distribution of phenazine-1-carboxylic acid-producing Pseudomonas spp. In the dryland agroecosystem of the Inland Pacific Northwest. Applied and Environmental Microbiology 79(12):3887-3891. Patzek, L.J., du Toit, L.J., Paulitz, T.C., and Jones, S.S. 2013. Stunting of onion caused by Rhizoctonia spp. isolated from the Columbia Basin of Washington and Oregon. Plant Disease 97(12):1626-1635. Poole., G. J., Smiley, R. W., Walker, C., Huggins, D., Rupp, R., Abatzoglou, J., Garland-Campbell, K., and Paulitz, T. C.2013. Effect of climate on the distribution of Fusarium species causing crown rot of wheat in the Pacific Northwest of the US. Phytopathology 103:1130-1140. Porch, T. G., Beaver, J. S., Abawi, G. S., and Estevez de Jensen, C. 2013. Registration of a small-red dry bean with low nitrogen fertility tolerance and root rot resistance, TARS-LFR1. Journal of Plant Registrations Vol. 7: (Accepted/in-press). Poudyal, D. S., Paulitz, T. C., Porter, L., Eggers, J. Hamm, P. and du Toit, L. 2013. Effect of timing of glyphosate application to a winter wheat cover crop on stunting of spring-sown onions caused by Rhizoctonia spp. in the Columbia Basin of Washington, 2012. Plant Disease Management Reports 7:V046. Poudyal, D. S., Paulitz, T. C., Porter, L., Eggers, J. Hamm, P. and du Toit, L. 2013. Efficacy of fungicides to manage onion stunting caused by Rhizoctonia spp. in the Columbia Basin of Oregon and Washington, 2011-2012. Plant Disease Management Reports 7:V047. Poudyal, D. S., Paulitz, T. C., Porter, L., Eggers, J. Hamm, P. and du Toit, L. 2013. Yield responses of three onion cultivars to stunting caused by Rhizoctonia spp. in the Columbia Basin of Oregon and Washington, 2012. Plant Disease Management Reports 7:V048. Raaijmakers, J. M., and Mazzola, M. 2012. Diversity and natural functions of antibiotics produced by beneficial and pathogenic soil bacteria. Annual Review of Phytopathology 50:403-424. Reardon, C. L., Strauss, S. L., and Mazzola, M. 2013. Effect of brassicaceae seed meal amendments on nitrogen cycling and nematode populations in orchard soils. Soil Biology & Biochemistry 57:22-29. Sanogo, S., and Ji, P. 2013. Water management in relation to control of Phytophthora capsici in vegetable crops. Agricultural Water Management 129:113-119. Sanogo, S., Schroeder, J., Thomas, S., Beacham, J., Fiore, C., Schmidt, N., Murray, L., and Liess, L. 2013. Weed species not impaired by Verticillium dahliae and Meloidogyne incognita interactions that damage chile pepper. Plant Health Progress (in press). Sanogo, S., Lujan, P., Puppala, N., Idowu, J., Grover, K. 2013. Evaluation of selected biorational products for efficacy against fungal pathogens of Valencia peanut. APS Joint Caribbean and Pacific Division Annual Meeting; Tucson, Arizona, June 17-19, 2013. Sanogo, S., and Lytle, M. 2013. Effect of the green algae Chlorella on vegetative growth and production of sporangia by Phytophthora capsici. APS Joint Caribbean and Pacific Division Annual Meeting; Tucson, Arizona, June 17-19, 2013. Schroeder, K. L., Martin, F. N., de Cock, A. W. A. M., Levesque, C. A. Spies, C. F. J. Okubara, P. A., and Paulitz, T. C. 2013. Molecular detection and quantification of Pythium species: Evolving taxonomy, new tools, and challenges. Plant Disease 97(1):4-20. Sikdar, P., Okubara, P., Mazzola, M., and Xiao, C. L. 201_. Development of PCR assays for diagnosis and detection of the postharvest pathogens Phacidiopycnis washingtonensis and Sphaeropsis pyriputrescens in apple fruit. Plant Disease: in press. Smart, C.D. (2013) A case study in documenting research. Phytopathology 103:S2.190 Smiley, R. W., Marshall, J. M., Gourlie, J. A., Paulitz, T. C., Kandel, S. L., Pumphrey, M. O., Garland-Campbell, K., Yan, G. P., Anderson, M. D. Floers, M. D., and Jackson, C.A. 2013. Spring wheat tolerance and resistance to Heterodera avenae in the Pacific Northwest. Plant Disease 97(5):590-600. Smith Becker, J., J. Borneman, and J.O. Becker 2013. Dactylella oviparasitica parasitism of the sugar beet cyst nematode observed in trixenic culture plates. Biological Control 64:51-56. Stanghellini, M., Mohammadi, M. and Adaskaveg, J. 2013. Regulatory effect of soil matric water potentials on a unique tripartite (Cucumis-Monosporascus-Olpidium) host-specific rhizosphere interaction. Phytopathology 103:S2 138. Stanghellini, M., Mohammadi, J. Adaskaveg, and H. Forster. 2013. Pythium brassicum: A novel host family-specific root pathogen. Phytopathology 103: S2 138. Strauss, S. L., Reardon, C. L., and Mazzola, M. 2014. The response of ammonia-oxidizer activity and community structure to fertilizer amendment of orchard soils. Soil Biology and Biochemistry 68:410-418. Summers, C.F., Park, S., Dunn, A.R., Rong, X., Everts, K.L., Meyer, S.L.F., Rupprecht, S.M., Kleinhenz, M.D., McSpadden Gardener, B., and Smart, C.D. (2014) Multi-State field trials demonstrate infrequent and site-specific effects of a single season of mixed-species cover crops on productivity and disease severity in tomato. Applied Soil Ecology accepted pending revision. Summers, C.F. and Smart, C.D. (2013) Fungal and oomycete pathogen detection in the rhizosphere of organic tomatoes grown in cover crop treated soil. Phytopathology 103:S2.141 Tadych M, Bergen MS, White JF Jr. (In Press). Epichloë spp. associated with grasses: new insights on life cycles, dissemination and evolution. Mycologia (Accepted November, 2013). Tancos, M.A. and Smart, C.D. (2013) Tomato fruit colonization by Clavibacter michiganensis subsp. michiganensis via external and internal routes. Phytopathology 103:S2.143 Tancos, M.A., Chalupowicz, L., Barash, I., Manulis-Sasson, S. and Smart, C.D. (2013) Tomato fruit and seed colonization by Clavibacter michiganensis subsp. michiganensis through external and internal routes. Applied and Environmental Microbiology 79:6948-6957. Weerakoon, D. M. N., Reardon, C. L., Paulitz, T. C., Izzo, A. D., and Mazzola, M. 2012. Long-term suppression of Pythium abappressorium induced by Brassica juncea seed meal amendment is biologically mediated. Soil Biology & Biochemistry 51:44-52. Witte, H., J. Smith Becker, and J.O. Becker 2012. In vitro growth response of Dactylella oviparasitica strain 50 to various culture media and environmental factors. J. Nematology 44: 497. Wyatt, L.E., Dunn, A.R., Falise, M., Reiners, S., Jahn, M.M., Smart, C.D., and Mazourek, M. (2013) Red harvest yield and fruit characteristics of Phytophthora capsici-resistant bell peppers in New York. HortTechnology 23:356-363. Xu, N., Ahuja, E., Janning, P., Mavrodi, D. V., Thomashow, L. W., and Blankenfeldt, W. 2013. Trapped intermediates in crystals of the FMN-dependent oxidase PhzG provide insight into the final steps of phenazine biosynthesis. Acta Crystallographica D69:1403-1413. Yan, G., Smiley, R. W., Okubara, P. A., Skantar, A.M., and Reardon, K. L. 2013. Developing a real-time PCR assay for detection and quantification of Pratylenchus neglectus in soil. Plant Disease 96 (6):757-764. Yan, G., Smiley, R. W., Okubara, P. A., and Skantar, A. 2014 Species-specific PCR assays for differentiating Heterodera filipjevi and H. avenae. Plant Disease: in press. Yang, J., P.M. Ruegger, M.V. McKenry, J.O. Becker and J. Borneman 2012. Correlations between root-associated microorganisms and peach replant disease symptoms in a California soil. PLoS ONE 7(10): e46420. doi:10.1371/journal.pone.0046420 Yin, C., Hulbert, S. H., Schroeder, K. L., Mavrodi, O., Mavrodi, D., Dhingra, A., Schillinger, W. F. and Paulitz, T. C. 2013. The role of bacterial communities in the natural suppression of Rhizoctonia bare patch of wheat (Triticum aestivum L.) Applied and Environmental Microbiology 79: 7428 Yuen, G. Y. 2013. Biological control of turfgrass diseases. Abstr. No.? Proceedings of the 10th International Conference of Plant Pathology. Beijing, August 25-30, 2013. Zahn, D.K., Haviland, D.R., Stanghellini, M.E., and Morse, J.G. 2013. Evaluation of Beauveria bassiana for management of citrus thrips (Thysanopter:Thripidae) in California Blueberries. J. of Econ. Entomol. 106:1986-1995. Zhongnan Zhang, Jianjun Hao, Jiazheng Yuan, Qijian Song, David L. Hyten, Perry B. Cregan, Guorong Zhang, Cuihua Gu, Zhou, H., Fang, H., Sanogo, S., and Zhang, J. 2013. Segregation analysis of Verticillium wilt resistance in fourteen Gossypium hirsutum × Gossypium barbadense hybrids. Beltwide Cotton Conference, San Antonio, TX, Janaury 2013. Zhou, X., Qian, G., Liu, F., and Yuen, G.Y. 2013 PilG in the biocontrol agent Lysobacter enzymogenes strain C3 positively regulates surface motility and negatively regulates antibiotic production. Phytopathology 103:S2.168. Extension and Technical Publications Abawi, G. S., K. Moktan, and J. Kikkert. 2013. Updating foliar diseases of beets and carrots and their management. Empire State Fruit and Vegetable Expo, Syracuse, NY. Proceedings, 4pp. (http://www.hort.cornell.edu/expo/proceedings.php) Abawi, G. S., and K. Moktan. 2013. Bloat Nematode: a re-emerging and damaging pest of garlic and other crops. Pages 168 170, Proceedings of the Mid-Atlantic Fruit and Vegetable Conference, Hershey, PA. Becker, J.O., A. Ploeg, and J. Nunez 2013. Management of root-knot nematodes with novel nematicides. California Tomato Research Institute 2012 Annual Report 109-112. Becker, J.O., A. Ploeg, J. Nunez 2013. Mitigating root-knot nematode damage in carrot production. 2012 Annual Report California Fresh Carrot Advisory Board. pp. 66-73. Benedict, C., and du Toit, L. J. 2013 Managing clubroot on crucifer crops. Whatcom Ag Monthly 2:10-12. Caldwell, B. Sideman, E., Seaman, A. Shelton, A. and Smart, C. (2013) Resource Guide for Organic Insect and Disease Management. Cornell University Press. 202 pp. ISBN 0-9676507-8-X Dunn, A., Reiners, S. and Smart C. (2013) Choosing bell pepper varieties to maximize Phytophthora tolerance and yield. Article for newsletters including VegEdge Fry, W.E., McGrath, M.T., Zitter, T.A., McLeod, A., Danies, G., Small, I., Myers, K., Everts, K., Gevens, A., Gugino, B.K., Johnson, S., Judelson, H., Ristaino, J., Roberts, P., Secor, G., Seebold, K., Snover-Clift, K., Wyenandt, A., Grunwald, N.J., and Smart, C.D. (2013) The 2009 Late Blight Pandemic in Eastern USA. An American Phytopathological Society APSnet feature article that can be found at <a href="http://www.apsnet.org/publications/apsnetfeatures/Pages/2009LateBlight.aspx">http://www.apsnet.org/publications/apsnetfeatures/Pages/2009LateBlight.aspx </a> Hansen, Z.R. and Smart, C.D. (2013) Tomato variety trial for resistance to late blight, 2012. Plant Disease Management Reports 7:V090. Online publication. doi: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Hao, J. J. Annual research report to Michigan Potato Industry Commission. East Lansing, MI. Jan. 17. Jones, L.A., Worobo, R.W., and Smart, C.D. (2013) Pathogens in Surface Irrigation Water. 2013 Proceedings: 58th New Jersey Agricultural Convention and Trade Show. Atlantic City, NJ (p. 114-116). Lange, H.W. and Smart, C.D. 2013. Evaluation of plant defense activators and bactericides for the control of black rot on cabbage, 2012. Plant Disease Management Reports 7:V060. Online publication. doi: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Lange, H.W., Smart, C.D., and Seaman, A.J. 2013. Evaluation of fungicides allowed for organic production on alternaria blight and downy mildew of cauliflower, 2012. Plant Disease Management Reports 7:V050. Online publication. doi: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Lange, H.W., Smart, C.D., and Seaman, A.J. 2013. Evaluation of fungicides allowed for organic production on downy mildew of cucumber, 2012. Plant Disease Management Reports 7:V049. Online publication. doi: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Lange, H.W., Smart, C.D., and Seaman, A.J. 2013. Evaluation of fungicides allowed for organic production on powdery mildew of zucchini, 2012. Plant Disease Management Reports 7:V051. Online publication. doi: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Lange, H.W., Smart, C.D., and Seaman, A.J. 2013. Evaluation of fungicides allowed for organic production on foliar diseases of tomato, 2012. Plant Disease Management Reports 7:V052. Online publication. doi: 10.1094/PDMR07. The American Phytopathological Society, St. Paul, MN. Okubara, P. A., Mahoney, A., and Hulbert, S. H. 2013. Pre-breeding for root rot resistance using root morphology and shoot length. 2013 Dryland Field Day Abstracts, Technical Report 13-1, p. 31-32. Smart, C.D. and Hansen, Z.R. (2013) Update on late blight. Proceedings of the 2013 York Fruit and Vegetable Expo, Syracuse, NY. On-line at <a href="http://www.hort.cornell.edu/expo/2013proceedings.php">http://www.hort.cornell.edu/expo/2013proceedings.php </a> Smart, C.D., Hansen, Z.R. and Tancos, M.A. (2013) Detecting downy mildew spores before symptoms develop. Proceedings of the 2013 York Fruit and Vegetable Expo, Syracuse, NY. On-line at <a href="http://www.hort.cornell.edu/expo/proceedings/2013/Vine%20Crops/Vine%20Crops%20Smart%20Downy%20Mildew.pdf">http://www.hort.cornell.edu/expo/proceedings/2013/Vine%20Crops/Vine%20Crops%20Smart%20Downy%20Mildew.pdf </a> Smart, C.D. and Lange, H.W. (2013) Best control of downy mildew in cole crops. Proceedings of the 2013 York Fruit and Vegetable Expo, Syracuse, NY. On-line at <a href="http://www.hort.cornell.edu/expo/proceedings/2013/Cole%20Crops/Cole%20Crops%20Smart%20Downy%20Mildew%20copy.pdf">http://www.hort.cornell.edu/expo/proceedings/2013/Cole%20Crops/Cole%20Crops%20Smart%20Downy%20Mildew%20copy.pdf </a> Smiley, R., Paulitz, T. C. and Marshall, J. 2012. Controlling root and crown diseases of small grain cereals. Extension Bulletin PNW 639. Suszkiw, Jan. "Crop-friendly bacteria tapped to battle fungal marauders," USDA ARS News, January 2013, p. 11. Zhou, X.G., Everts, K.L. and Zhou, C., 2013. Field evaluation of Brassica biofumigation cover crops for management of Fusarium wilt in watermelon, 2009. Plant Dis. Mang. Rep. 7:V141. Online publication. doi: 10.1094/PDMR07 Extension and Outreach Presentations Becker, J.O. Turfgrass and Landscape Institute, Etiwanda Gardens, Rancho Cucamonga, CA, December 11, 2013. "Natural Enemies of Plant Parasitic Nematodes". (invited presentation) Becker, J.O. Annual Fall Desert Crops Workshop 2013. El Centro, CA, December 5, 2013. "New nematode management tools in processing tomato production." (invited presentation) Becker, J.O. Desert Valleys CAPCA Coachella Valley Continuing Education Meeting, El Centro, CA, November 14, 2013. "Nature of botanical and microbial nematicides and their performance in root-knot nematode infested SoCA field trials." (invited presentation) Becker, J.O. CAPCA Tree & Vine Seminar, San Marcos, Community Center, November 7, 2013. "Nematodes in wine grapes in Southern California vineyards." (invited presentation) Becker, J.O. Turf and Landscape Field Day, UC Riverside, Sept 12, 2013. "Root-knot nematode studies on Brachypodium distachyon." (invited presentation) Becker, J.O. Nematology Workshop for Industry Personnel, Harris Ranch, Coalinga, Aug 7, 2013. "Plant parasitic nematodes in California crops: biology, disease diagnosis, and management." (invited presentation with hands-on demonstrations) Becker, J.O. CAPCA and UCCE IPM Seminar, UC South Coast Research and Extension Center, Irvine, CA, May 16th, 2013. "Plant parasitic nematode management research at SCREC." (invited presentation). Becker, J.O. Conference on Soilborne Plant Pathogens, Corvallis, OR, March 27, 2013. "Nematode suppressive organisms: Are we investigating the right target?" (invited presentation) Becker, J.O. UCCE Landscape Disease Symposium, Hansen Agricultural Center, Santa Paula, CA, Feb 28, 2013. "Lessons from nematode-suppressive soils." (invited presentation) Becker, J.O. University Extension Turf Management Certificate Course, 3 hr class plus on-line feed -back, UC Riverside Extension, Feb 26, 13, Riverside, CA. "Turf Management: Plant Parasitic Nematodes." (invited presentation) Becker, J.O. Sugar beet Annual meeting, Holtville, January 30, 2013. "Biological, biorational and chemical population suppression of sugar beet cyst nematodes." (invited presentation) du Toit, L. J. "Disease management in carrot seed crops: What? When? How?" Columbia Basin Vegetable Seed Assoc. Annu. Meeting, 15 Jan. 2013, Moses Lake, WA. du Toit, L. J. "Disease management in onion seed crops: What? When? How?" Columbia Basin Vegetable Seed Assoc. Annual Meeting, 15 Jan. 2013, Moses Lake, WA. du Toit, L. J. "Does this product really work? Distinguishing sound science from hot air in product promotional materials." General Vegetable Session, Pacific Northwest Vegetable Association 26th Annual Conference & Trade Show, 13-14 Nov. 2013, Kennewick, WA. du Toit, L .J. "Evaluation of Proline for management of Fusarium wilt in spinach seed crops." Puget Sound Seed Growers Annu. Meeting, 25 Jan. 2013, Mount Vernon, WA. du Toit, L. J. "Fusarium and Verticillium wilts in spinach seed production: Research update." 2013 Wilbur Ellis/Alf Christianson Seed Co. Vegetable Seed Growers Meeting, 6 Feb. 2013, Burlington, WA. du Toit, L. J. "Managing seed borne diseases: Lessons learned from Verticillium and spinach seed." Invited presentation at Seed Central Science, organized by the Seed Biotechnology Center, Univ. of California Davis Seed Science Center, 14 Feb. 2013, Davis, CA. du Toit, L. J. "Management of Verticillium associated with spinach seed." Invited presentation, Annual Research Symposium of the California Leafy Greens Research Board, 19 Mar. 2013, Harris Ranch, CA. Followed by panel discussion on Verticillium in lettuce and spinach, with L. du Toit (Washington State Univ.), and K. Subbarao and S. Koike (Univ. of California-Davis). du Toit, L. J. "Management of Verticillium in spinach: Research report." Puget Sound Seed Growers Annu. Meeting, 25 Jan. 2013, Mount Vernon, WA. du Toit, L. J. "Management of Verticillium in spinach: Final report." Presented in Permanent Research Fund Committee and Emerging Diseases Committee meetings, American Seed Trade Assoc. 52nd Vegetable & Flower Seed Conf., 26-29 Jan. 2013, Scottsdale, AZ. du Toit, L. J. "Mycorrhizae in onion bulb crops." Organic Session, Pacific Northwest Vegetable Association 26th Annual Conference & Trade Show, 13-14 Nov. 2013, Kennewick, WA. du Toit, L. J. "Neck rot identification and management based on Achilles heel". Invited presentation, United Kingdom Onion and Carrot Conference & Exhibition, 20-21 Nov. 2013, Peterborough, UK. du Toit, L. J. "Onion neck rot: Effective management based on Achilles heel." Invited presentation, 62nd Annual Muck Vegetable Growers Conf., 3-4 Apr. 2013, Bradford, Ontario, Canada. du Toit, L. J. "Why was pink root so prevalent in 2013?" Onion Session, Pacific Northwest Vegetable Assoc. 26th Annu. Conf. & Trade Show, 13-14 Nov. 2013, Kennewick, WA. Everts, K. L. 2013. Fusarium oxysporum f. sp. niveum on Watermelon: The Search for New Solutions to a Re-emerging Problem. Sustainable Agriculture Seminar Series, Beltsville Agriculture Research Center, Beltsville, MD. Feb. 13, 2013 Everts, K. L. "Multiple Tactics to Control Diseases in Vine Crops." Delaware Agriculture Week, Vine Crops Session, Harrington, DE. Jan. 15, 2013 Everts, K. L. "Update on Disease Control in Vegetable Crops." WMREC Horticultural Crops Twilight Meeting, Keedysville, MD. Aug. 21, 2013 Everts, K. L. "Update on Disease Control in Vegetable Crops." Wye Research and Education Center Horticultural Crops Twilight Meeting, Queenstown, MD. Aug 28, 2013 Everts, K. L. "Vegetable Disease Update and Research in Maryland and Delaware in 2013." Mid-Atlantic Vegetable Workers Conference, Newark, DE. Nov. 6, 2013 Gatch, E. W., and du Toit, L. J. "Management of Fusarium wilt in spinach seed crops." Puget Sound Seed Growers Annu. Meeting, 25 Jan. 2013, Mount Vernon, WA. Gatch, E. W. and du Toit, L. J. "Shifts in soil microbial community associated with limestone-mediated suppression of spinach Fusarium wilt." 59th Conf. Soilborne Plant Pathogens, 26-28 Mar. 2013, Corvallis, OR. Hao, J. J. Title: "Bio-based Strategies to Manage Potato Diseases". 2013 Potato Pest Management Conference. Presque Isle Inn and Convention Center, Presque Isle, ME. Dec. 4, 2013. Himmelstein, J.C., Everts, K., Balci, Y. 2013. Watermelon root arbuscular mycorrhizal colonization is enhanced following Vicia villosa and Trifolium incarnatum cover crops. Shephardstown, WV. 2013 Annual Meeting of the Potomac Division of the American Phytopathological Society. Shepardstown, WV. Himmelstein, J.C., Everts, K.L., Maul, J. and Balci, Y. 2013 General suppression of Fusarium wilt of watermelon via spring incorporated Vicia villosa and Trifolium incarnatum cover crops. 2013 Annual Meeting of the American Phytopathological Society. Austin, TX. Jiang, H. H., Meng, Q., and Hao, J. J. 2013. Potentials and mechanisms of Bacillus amyloliquefaciens BAC03 in plant disease control. 73rd Annual Meeting of the Northeastern Divisin of the American Phytopathological Society. Oct. 23-25. Mu, W., Li, B., Chen, C., Hao, J., and Liu, X. 2013. Molecular mechanisms of thifluzamide resistance in Rhizoctonia solani. 73rd Annual Meeting of the Northeastern Divisin of the American Phytopathological Society. Oct. 23-25. Paulitz, T. C. and Schillinger, W. "Management of Fresh Wheat Residue for Irrigated Winter Canola Production". PNW Canola Commission Meeting, Moscow, ID. Jan 30, 2013. Paulitz, T. C. "Root Disease Research at ARS Pullman-Whats New?" Spokane Farm Forum, Ag Expo, Feb. 5, 2013. Paulitz, T. C. "Fusarium Crown Rot on Wheat: Prebreeding and Development of Tools for Genetic Disease Management". Washington Grain Commission, Pullman, WA Feb. 19, 2013. Paulitz, T. C. titled "Management of Fresh Wheat Residue for Irrigated Winter Canola Production". Washington State Department of Ecology, Ag Burning Task Force. Spokane, WA. June 11, 2013. Schroeder, K. L. Diseases in canola. Far West Washington Winter Conference, Pasco, WA. December 11, 2012. Schroeder, K. L. Survey of Rhizoctonia spp. from wheat soils in the U.S. and determination of pathogenicity on wheat and barley. Global Root Health Forum, Beijing, China. September 3, 2013. Schroeder, K. L. The dynamics and ecology of Pythium species in cereal-based cropping systems as determined by real-time PCR. Seed and Seedling Oomycete Summit, Manhattan, KS. June 11, 2013. Schroeder, K. L. Overview of soilborne pathogens: Rhizoctonia, Fusarium and take-all. Montana State University Extension Ag Tour, Pullman, WA. June 6, 2013. Schroeder, K. L. Temporal shifts in soilborne pathogen populations in dryland wheat cropping systems. Conference on Soilborne Plant Pathogens, Corvallis, OR. March 27, 2013. Schroeder, K. L. Diseases in canola. 2013 WSU Oilseed Production and Marketing Conference, Kennewick, WA. January 22, 2013. Stanghellini, M. Storkan-Hanes-McCaslin Foundation, June 24, 2012, San Marcos, California. Management strategies for soilborne root-infecting pathogens. 30 minutes presentation. Graduate student theses supervised Alcala, Ana Vida C. 2013. Management of damping-off caused by Pythium spp. in organic vegetable production in the Pacific Northwest. PhD dissertation, Washington State University, Pullman, WA. Escobar, Carolina. 2013. Chapter three: management of Sclerotinia stem rot by integration of biocontrol and chemical strategies under field. M.S. Thesis., Michigan State Unversity. Gatch, Emily W. 2013. Management of Fusarium wilt in spinach seed crops in the maritime Pacific Northwest USA. PhD dissertation, Washington State University, Pullman, WA. Himmelstein, J., 2013. Mechanisms of disease suppression by a hairy vetch (Vicia villosa) cover crop on Fusarium wilt of watermelon and the efficacy of the biocontrol Actinovate.). Ph.D. Dissertation. U. of Maryland Meng, Qingxiao. 2013. Characterization of Bacillus amyloliguefaciens strain bac03 in disease control and plant growth promotion. Ph.D. Thesis.Michigan State Unversity. Thompson, Alison. 2013. Identifying root-lesion nematode (Pratylenchus spp.) resistance and functional mechanisms in wheat. Washington State University, Pullman, WA.

Impact Statements

In our replant site, stramenopiles with suppressive potential appeared to be of major importance. We obtained further evidence that with cyst nematodes the young females are the primary target of D. oviparasitica. Abamectin seed coating reduces early root-knot nematode attack in carrots and might be useful in combination with fungal or bacterial biocontrol agents.
We determined various aspects of the host-microbe interactions between the fungus Dactylella oviparasitica and the plant-parasitic nematode Heterodera schachtii, toward the goal of developing a more effective tool for making sugar beet planting decisions.
Reducing irrigation frequency and duration, coupled with incorporation of a surfactant and Quadris into the irrigation water, led to disease management and recovery of severely infected fields.
Growers have been reluctant to adopt the practice of use of Vicia villosa cover crop prior to watermelon production. Their concerns are that the seed of V. villosa is hard and can survive over the winter in the mid-Atlantic. Therefore, V. villosa may become a weed problem is subsequent crops. The demonstration that Trifolium incarnatum also confers benefits in Fusarium wilt suppression may offer growers a viable alternative.
The biocontrol agent bacterial strain BAC03 can be potentially used for potato common scab control at a large scale. The studies provide practical information in using bacterial strain BAC03 as a biological control agents. Growers will learn when and how to apply the product in controlling potato common scab. It helps to move the product to be commercialized.
Discovery of controlling mechanisms for antagonism factors may lead to the development of more field effective biocontrol agents. In addition to providing a new tool for disease management, use of such agents is compatible with other management practices and might result in reduced chemical fungicide inputs.
Teaching activities provided critical training relating to biological pest control to the next generation of plant scientists and agriculturalists.
Detailed information on the impact of individual and combined crop production practices will be valuable inputs to stakeholders in the implementation of a holistic and sustainable root disease and soil health management programs. Thus, results obtained from these studies will aid growers and other agricultural service providers in selecting the appropriate crops and other production practices. Successful management will contribute to increasing farm profitability and environmental quality.
Growers, extension educators and crop consultants value the work done as part of this multi-state project. The ability to provide information on soil-borne disease control from other states certainly enhances the impact of our talks. Many grower practices including cultural controls, cover crop treatments and use of resistant varieties have been implemented because of this project.
Understanding of natural suppression of soilborne diseases may lead to development of cultural methods to enhance and accelerate the development of suppression in grower fields. Identification of bacterial community associated with natural suppression of Rhizoctonia root rot of wheat in the field may lead to development of cultural tools to enhance this sustainable method of disease management.
Agricultural limestone amendments to soil as well as evaluating the level of risk of individual fields to spinach Fusarium wilt using a soil bioassay have enabled growers to reduce the rotation interval between spinach seed crops by as much as 50% without incurring major losses to Fusarium wilt. This has the potential to double the carrying capacity for spinach seed production in the USA.

Date of Annual Report: 01/09/2015

Report Information

Annual Meeting Dates: 10/24/2014 - 10/24/2014
Period the Report Covers: 10/01/2013 - 09/01/2014

Participants

Adesemoye, Tony (tony.adesemoye@unl.edu) - University of Nebraska;
Becker, Ole (obecker@ucr.edu) - University of California, Riverside;
Borneman, James (borneman@ucr.edu) - University of California, Riverside;
Hao, Jianjun (jianjun.hao1@main.edu) - University of Maine;
Kahn, Michael (kahn@wsu.edu) - Washington State University;
Paulitz, Tim (paulitz@wsu.edu) - ARS-WA;
Ploeg, Antoon (antoon.ploeg@ucr.edu) - University of California, Riverside;
Smart, Christine (ads14@cornell.edu) - Cornell University, Geneva NY

Brief Summary of Minutes

Minutes

2014 Meeting of the Multistate Project W3147

October 24, 2014

Mission Inn, San Diego Room

Riverside, CA

Ole Becker, Chair

Antoon Ploeg, Secretary

James Borneman, local arrangements

Members in attendance:

Tony Adesemoye (NE), Ole Becker (CA), James Borneman (CA), Jianjun Hao (ME), Michael Kahn (WA), Tim Paulitz (WA), Antoon Ploeg (CA), Chris Smart (NY).

The meeting started at 8:30 AM with the chair’s welcome and self-introduction of attendees.

The minutes from the 2013 meeting were approved.

Michael Kahn (WA, USDA program director) provided details and background on the new REEport system that is now used to submit, renew, and report on projects.

December 5, 2015 was selected as the data for the next meeting. Location: Mission Inn, Riverside, CA.

As the assigned secretary (Jennifer Parke) was prevented from attending the meeting, Antoon Ploeg volunteered to be the secretary for this meeting and to be the Chair for the 2015 meeting.

Progress reports:

Antoon Ploeg reported on a needle nematode in California date palm, and on nematicide trials in vegetable crops.

Jianjun Hao reported on Oomycete diseases, particularly pink-rot, in potato.

Tim Paulitz presented results of studies on effects of ‘till’ versus ‘no till’ systems on soil bacterial populations. He also reported on the use of biofumigation to alleviate replant problems in apple, on the occurrence of cyst nematodes in wheat, and on Rhizoctonia disease in onion and pea.

James Borneman gave an overview of a project focused on protecting citrus from greening disease by using “phytobiomes” from symptomless trees.

Ole Becker reported on progress of his studies on nematode suppressive soils, and on Anguina nematode problems in a golf course at Pebble Beach, CA.

Tony Adesemoye introduced himself to the group, and presented an overview of current research on charcoal rot (Macrophomena) and Fusarium in soybean and corn at the University of Nebraska.

Chris Smart reported on studies on fungal and bacterial diseases in vegetable crops, with an emphasis on work related to Phytophthora blight caused by P. capsici.

Michael Kahn presented his findings on the biochemical pathways involved in nitrogen fixation in alfalfa.

Before adjourning the meeting, the members thanked James Borneman for an outstanding job in handling the local arrangements.

Submitted: Antoon Ploeg.

Accomplishments

Objective 1. Evaluation of Tillage Practices on Root Rot Severity and Yield of Snap Beans: The trial was established in the experimental root rot field at the Vegetable Research Farm of the NYSAES, Cornell University in Geneva, NY. This 2-acre field has been in continuous bean production for over 20 years and is heavily infested with the bean root rot pathogens Fusarium solani f. sp. phaseoli, Pythium ultimum, Thielaviopsis basicola and Rhizoctonia solani. The overwintered grain rye cover crop was sprayed with “Round-up” in mid May and then mowed on May 27, 2014. The three tillage systems (conventional, ridge-till, and zone-till) were prepared on May 27 as strips of about 0.5 acre (400 ft. x 60 ft.). On June 10, the snap bean variety “Caprice” was planted in all the tillage plots using a 2-row (30-inch apart) Monosem planter that banded 350 lbs./A of a complete fertilizer (10-10-10, NPK). Immediately after planting, all plots were sprayed with the herbicides Dual Magnum (1.5 pt./A). Emergence counts and root rot severity ratings were made on July 18th. Plots were harvested (4 sections/tillage system) on August 18th. Results obtained are summarized in Table 1. There were only small differences in the emergence counts and the number of productive plants at harvest among the three tillage practices. However, the highest total plant weight and the pod weight were significantly higher in the ridge-till system. Interestingly, the yield of bean in the strip-till system was numerically higher than that of the conventional-till system. Change in a Phytophthora capsici population over time. To identify control strategies, it is important to know how a pathogen population in a field is changing over time. Populations of the vegetable pathogen Phytophthora capsici are often highly diverse, with limited gene flow between fields. To investigate the structure of a newly established, experimental population, an uninfested research field was inoculated with two single zoospore isolates of P. capsici in September 2008. From 2009 through 2012, approximately 50 isolates of P. capsici were collected from the field each year and genotyped using five microsatellite loci. The same two isolates were also crossed in the lab. High levels of diversity were detected in the research field, with 26 to 37 unique multilocus genotypes detected each year. Through 2012, genotypic diversity did not decline, and no evidence of genetic drift was observed. However, during the 2011 and 2012 growing seasons, a total of four new alleles not present in either parental isolate were observed in the field. Selfing (but not apomixis) was observed at low frequency among in vitro progeny. In addition, evidence for loss of heterozygosity was observed in half of the in vitro progeny. These results suggest that recombination, mutation and loss of heterozygosity can impact the genetic structure observed in P. capsici populations. We are continuing to follow this population by collecting 50 isolates per year, and we are now using the more robust genotyping-by-sequencing method to genotype isolates. This method enables us to use about 66,000 SNPs to look at diversity within a population. We are investigating the potential for solarization to control soilborne Phytophthora spp. in container nurseries. Controlled experiments in the lab conducted at constant temperature examined the thermotolerance of Phytophthora ramorum and P. pini, as well as their response to different water potentials and fluctuating temperature. Both pathogens have greater tolerance to heat at lower water potential (drier conditions). P. pini showed greater heat tolerance than P.ramorum. Intermittent heat was less damaging to the pathogens than continuous heat. Field trials with P. ramorum and P. pini (San Rafael, CA) and with P. pini (Corvallis, OR), and showed that the predictive model of solarization efficacy established from lab experiments is reliable. Four Phytophthora species (P. ramorum, P. pini, P. gonapodyides, and P. taxon PgChlamydo) were compared for their ability to tolerate high temperatures to predict the efficacy of solarization in decontaminating Phytophthora-infested soils. To test species responses to temperature, we exposed inoculated rhododendron leaves to different heat regimes in the laboratory. Using a thermocycler, samples of the four Phytophthora species were subjected to a temperature gradient ranging between 30° and 40° C for 72 hours before plating on selective media. P. pini tolerated temperatures up to 38?C whereas P. ramorum was not recovered after exposure to 36? C for 72 hours. P. gonapodyides and PgChlamydo were the least thermotolerant species. In addition, soil solarization trials were conducted in Oregon and California to compare recovery under field conditions. We compared species, treatment (solarized and non-solarized), the depth of buried inoculum (0 cm-15 cm), duration of treatment (2 or 4 weeks), and different climates (Oregon and California). We found that solarization was effective in killing Phytophthora species buried in the top 15cm of soil in both Oregon and California with the exception of P. taxon PgChlamydo, which survived at this depth in the California trial. In 2013 and 2014, solarization trials were conducted in a total of 42 nursery sites ranging from southern California to northern Washington to develop a data set on soil temperatures measured over time at different depths (0, 5, 10, 15 cm) with and without solarization. Temperatures in the solarized plots exceeded the critical threshold of >35° C for a minimum of 96 hours - conditions reported to kill Phytophthora ramorum - in 21 of 26 trials in 2013 and in all 16 of the 2014 trials. We anticipate linking this soil temperature data to ambient air temperature, solar radiation, and daylength from nearby meteorological stations to develop a simple predictive model requiring input of only location and start date to determine the time required to achieve effective disinfestation with soil solarization. A related field experiment in 2014, in collaboration with Gary Chastagner and Marianne Elliott at WSU-Puyallup, compared the efficacy of soil solarization and soil steaming on recovery of P. plurivora, P. gonapodyides and P. taxon PgChlamydo inoculum buried at 0, 5, 10, 15 and 30 cm beneath the soil surface. Solarizing for 4 weeks eliminated recovery of all 3 Phytophthora taxa from 0-10 cm, whereas soil steaming eliminated recovery from 0-15 cm. Neither treatment eliminated recovery from the 30 cm depth. Another solarization experiment was started in the same location two weeks earlier; interestingly, soil temperatures in the earlier trial exceeded the critical temperature threshold at all soil depths tested (0-15 cm) suggesting that an early July start date may be necessary for soil solarization to be effective in Washington locations. We verified that Olpidium bornovanus (No. K981451) was the cause of vine decline of mature watermelon plants and that infection and disease severity were related to a daily irrigation regime. Analysis of IT 1 and 2 gene sequences revealed a 99% identity to O. bornovanus cultures in GenBank (Accession Nos. AB205215 and AB665758). We are working with growers to establish a management strategy. We are continuing work on a newly discovered culturable mycorrhizal fungus, an ascomycete isolated from native desert soils in southern Arizona and California. A new project evaluating the effect of cover crops on diseases and pathogens in a following soybean crop was initiated in 2014. Treatments include several fall planted cover crops including cereal rye, hairy vetch, hairy vetch/rye mix, mustard, and a fallow control, superimposed on tillage treatments of ridge-till and chisel plowing. Root of soybean seedings (R3) were evaluated for disease and foliar and root diseases were evaluated when the plants were nearing maturity (R6-7). We are endeavoring to understand soils that naturally inhibit plant pests and disease, termed suppressive soils. Key steps in realizing the potential of these soils are to identify the causal organisms and then understand the agronomic and environmental factors that enable them to function. Armed with such knowledge, it should be possible to develop effective and sustainable pest management strategies through the application of the organisms and through agronomic practices that influence their populations. To date, we have identified several fungi involved in suppressing sugarbeet cysts nematodes (Dactylella oviparasitica and Fusarium oxysporum) and root-knot nematodes (Pochonia chlamydosporium and a Tetracladium sp.). We have also identified new Dactylella oviparasitica phylotypes, which suggests that these fungi may represent a large group of potentially effective biological control agents, and which can be found worldwide. In addition, we have determined that soils with no detectable Dactylella populations can harbor this fungus, and which can dramatically increase during one host cropping cycle. This is a key finding, suggesting that standard methods for screen soils for putatively protective microorganisms will not work. We have also presented a new approach and supporting data for using Dactylella population densities in planting decisions models. Another long-term goal is to develop new methods that enable a greater understanding of the roles microorganisms play in processes such as nematode and replant disease. In prior research, we developed several molecular and computational methods that should facilitate a greater understanding of these phenomena. We are continuing these efforts by developing a high-throughput method for microbial community analyses, a software package for designing PCR primers and probes, and a statistical method for classifying soils (or other entities). In a preliminary study looking at mycoviruses S. sclerotiorum, a high-throughput sequencing-based metatranscriptomic approach was used to rapidly screen 135 isolates for the presence of mycoviruses. The analysis identified partial or complete genome sequences of 43 mycoviruses, 37 of which had not been described previously. The novel mycoviruses were from eight distinct lineages, and included families and genera that previously contained no fungal-infecting representatives, including Alphacryptovirus, Barnavirus, Benyvirus, Bornaviridae, Idaeovirus, Ophiovirus, Ourmiavirus, Tombusviridae and Tospovirus. The metatranscriptomic screenings widened the range and diversity of mycoviruses, identified more potential biological control agents, and may provide resources to study the interactions between fungi and their plant hosts. A recombinant strain of Sclerotinia sclerotiorum hypovirus 2 (SsHV2) was identified and sequenced from a North American S. sclerotiorum isolate (#328) from lettuce (Lactuca sativa L.) The assembled nucleotide sequence was up to 92% identical to two recently reported SsHV2 strains, but contained a deletion near its 5’ terminus of more than 1.2 kb relative to the other SsHV2 strains and an insertion of 524 nt that was distantly related to Valsa ceratosperma hypovirus 1 (Figure 1). This suggests that the new isolate is a heterologous recombinant of SsHV2 with a yet uncharacterized hypovirus. The new strain was named Sclerotinia sclerotiorum hypovirus 2 Lactuca (SsHV2L). Sclerotinia sclerotiorum isolate #328 was coinfected with a strain of Sclerotinia sclerotiorum endornavirus 1 and debilitated compared to cultures of the same isolate that had been cured of virus infection by cycloheximide treatment and hyphal tipping. To confirm that SsHV2L was the causal agent of hypovirulence, a full-length cDNA of the 14,538-nt viral genome was cloned. Transcripts corresponding to the viral RNA were synthesized in vitro and transfected into a virus-free isolate of S. sclerotiorum, DK3. Isolate DK3 transfected with SsHV2L was hypovirulent on soybean and lettuce and exhibited delayed maturation of sclerotia relative to virus-free DK3, completing Koch’s postulates for the association of hypovirulence with SsHV2L. The construction of an infectious clone of SsHV2L allows future exploration of the interactions between SsHV2L and S. sclerotiorum, a widespread fungal pathogen of plants (Marzano et al. 2015). One of the identified viruses, SsHV2L, significantly reduces the virulence of S. sclerotiorum and is potentially useful as a biological control agent to reduce crop losses caused by the fungus. An infectious cDNA clone was constructed of SsHV2 and methods were developed to efficiently introduce the cDNA clone into isolates of S. sclerotiorum. In addition to potentially being a biological fungicide, modified virus genomes can be used to study of the biology and development of S. sclerotiorum and its interactions with plant hosts through virus-induced gene silencing and by transiently expressing genes in S. sclerotiorum at high levels. Using pyrosequencing, we compared bacterial communities at the family level between long-term no-till and conventionally tilled soils, in side-by side plots, over two years in two locations in Washington and Idaho. Many bacterial families were more predominant in either rhizosphere or bulk soil, but tillage practice had no significant effect on most families. The only exception was Chitinophagaceae, which was more frequent in bulk, conventionally tilled soil and Solirubrobacteraceae and Rhodospirillaceae, which were more frequent in bulk, no-till soil. No rhizosphere families were influenced by tillage, suggesting that the plant is much stronger driver of communities, at least for bacteria. Over the last 4 years, we have defined the composition of Rhizoctonia and Rhizoctonia-like groups that cause bare patch disease in onion and pea in the irrigated Columbia Basin of Washington and Idaho. Over 11 groups were detected, with AG-8, AG-4 and AG 2-1 being the most pathogenic on pea, and AG-8 and AG-4 on onions. Onions are dependent on arbuscular-mycorrhizal fungi for uptake of P. However, soils are often fumigated in onion production in the irrigated Columbia Basin, which may eliminate this beneficial symbiosis. However, a survey has indicated that AM fungi are equally present in both organic and conventional tillage. We will use next-gen sequencing to identify the species. We are presently investigating the possibility that AM fungi may help protect onions against pathogens such as Rhizoctonia and Phoma. WA-ARS researchers in Wenatchee characterized the microbial communities in apple replant, as affected by biofumigation with Brassica seed meal and telone-C17. After two growing seasons, the bacterial and fungal community were identical between the non-fumigated treatment and the treatment fumigated with telone-C17, indicating that the communities reoccupied the niche. However, the communities in the biofumigated treatments were distinct after two years, indicating that a long-term shift had occurred. In this period we examined bacterial endophytes of several plants that improved plant growth by inhibiting plant pathogenic fungi, up-regulating host stress defensive genes, or deterring insect feeding. The plants we studied include vanilla orchids (Vanilla phaeantha), English Ivy (Hedera helix), tropical corn (Zea maydis indurata), and Hosta spp. Bacillus amyloliquefaciens was encountered an endophyte in vanilla, English ivy, and Hosta spp. We examined the pathogen and pest protective effects of these of B. amyloliquefaciens on these hosts. We propose that use of endophytic strains B. amyloliquefaciens may be a viable option for protecting plants from disease and pests. We initiated the patent process for use of a B. amyloliquefaciens strain (Blu-v2) in ornamental Hosta cultivars. The nematophagous fungus Dactylella oviparasitica (syn. Brachyphoris oviparasitica) is the primary causal agent of a long-term Heterodera schachtii population suppression in a UCR research field site. The geographical distribution of this organism is unknown. A real-time PCR assay was used in a survey of 80 field samples collected from sugar beet fields in the Imperial Valley, CA. Seventeen samples tested positive for D. oviparasitica. Objective 2. As part of a climate change CAP grant, we have been documented the distribution of soilborne pathogens across a wide variety of cropping system zones in eastern Washington. Using real-time PCR technology developed by ARS, we quantified Rhizoctonia groups over 2 years, and correlated the populations with climatic factors from models developed at a 4-km scale, using principal component analysis and correlation analysis. R. solani AG-8 was more associated with sandy soils and low precipitation, but R. oryzae was more influenced by temperature. This information will be used for modelling under future climate change scenarios. Soybean roots, bulk soil, and rhizosphere soil were collected from plants grown in cover crop tillage experimental plots when the soybean plants were in the seedling (R3) stage. DNA was extracted from the roots and rhizosphere soils taken from the fallow and rye plots in both the ridge-till and chisel-plow treatment main plots. These DNA extracts will be assayed for soybean pathogen populations using qPCR. The DNA extracts will also be used to evaluate microbial community structures using a method involving Illumina sequencing. We examined the role of seed-vectored rhizobacteria on seedlings of several turf grasses, including annual bluegrass (Poa annua), tall fescue (Festuca arundinacea), and perennial ryegrass (Lolium perenne). Our studies suggest: 1) seed-vectored rhizobacteria colonize seedling roots and influence their development; 2) reactive oxygen secretion by seedling roots plays a role in organic nitrogen procurement by denaturing proteins in the vicinity of roots (daytime activity); 3) plant root and rhizobacterial proteases disarticulate denatured proteins prior to absorption by roots (nighttime activity); and 4) rhizobacteria also efficiently scavenge nitrogen from air, probably as ammonia. We conclude that the non-pathogenic rhizobacteria may play a role in reducing colonization of roots by potential pathogens, but their primary role is to participate in the scavenging of organic nitrogen from other rhizosphere microbes. We speculate that the oxidative activities occurring on grass roots may also cause an up-regulation of the stress genes that could increase tolerance of grasses to abiotic and biotic stresses. The procurement of organic nitrogen by grasses may also contribute to the overall hardiness of plants. We additionally worked out an assay for detection of non-pathogenic bacteria in and on plant roots that uses reactive oxygen staining to visualize oxidative activities on roots. (Collaboration with Niklaus Grunwald, USDA-ARS) Infested leaf debris incorporated into soils is a potential source of inoculum contributing to the persistence of P. ramorum at recurrent positive nurseries. To assess the risk of soilborne inoculum, we buried infected rhododendron leaf disks at a depth of either 5 or 15 cm at an experiment soil plot located at the National Ornamentals Research Site at Dominican University. In 5-week intervals since June 2014, we baited surface water with uninfected rhododendron leaf disks, and retrieved buried inoculum for the assessment of survival (% disks in which P. ramorum was recovered after plating on selective media) and sporulation capacity (average # of sporangia produced from 10 disks after 1 week incubation in water). Recovery of P. ramorum has been consistently lower from soil-incubated disks relative to controls stored at 4oC, but has remained above 60%. Sporulation has declined significantly over time, and has been consistently lowest within a single recovery period for inoculum at 5 cm. New infested leaf disks have also been introduced for a 2-day interval during most recovery periods. While overall recovery of P. ramorum after 2 days has been high, sporulation has significantly decreased relative to controls. P. ramorum has only been successfully baited from one plot with inoculum re-introduced at 5 cm (2 positive baits of approx. 4,600 baits plated to date). Although soilborne P. ramorum survives over the summer in soils, its contribution to plant infection may be low because of the rapid decline in sporulation capacity. The effects of soil solarization on soil microbial communities is being explored using Illumina sequencing of extracted bacterial and fungal DNA. Host resistance is a key management strategy for root and crown rot caused by Phytophthora capsici in pepper. An isolate of P. capsici constitutively expressing a gene for green fluorescent protein was used to investigate pathogen interactions with roots and crowns of a susceptible (Red Knight) and two resistant (Paladin and CM-334) pepper cultivars. Zoospores attached to and germinated on roots of all three cultivars equally well at 30 and 120 minutes post inoculation (pi), respectively. At 3 days pi, significantly more secondary roots had lesions on Red Knight plants compared to Paladin and CM-334 plants, although hyphae had colonized tips of at least some secondary roots of all cultivars. By 4 days pi, necrotic lesions had formed on the primary root of Red Knight, but not Paladin and CM-334 plants. Although hyphae were visible in the crown tissue of Red Knight plants by 3 days pi, no hyphae were observed in crowns of Paladin or CM-334 plants, even after 10 days pi. Expression of four defense genes in stems and leaves of inoculated Red Knight, Paladin, and CM-334 plants at 8 and 10 hours pi was quantified, but no differences were observed among cultivars at either time point. Objective 3 We are determining the efficacy of foliar applications of anti-transpirants and surfactants to prevent leaf infection by zoospores of Phytophthora ramorum. We used detached leaf assays to first assess which compounds were most effective in preventing infection of rhododendron. Whole rhododendron plants were then treated once at the start of a four week trial with the most active compounds, and kept outdoors, exposed to overhead irrigation and rain. Each week, leaves from the treated plants were detached and inoculated with zoospores in the lab. Disease severity (percent lesion area) was analyzed with image analysis. These trials have shown consistently lower disease incidence and severity in leaves treated with the anti-transpirants (Nu-Film, Anti-Stress) and the surfactant Zonix compared to untreated controls. Efficacy of all products declined over the 4-week period. We are also testing some of these treatments to determine if they will reduce sporangia production when applied to leaves infected with P. ramorum (Collaboration with Carol Mallory-Smith, OSU) We compared seven treatments for the management of Nostoc, a soilborne cyanobacterium, that creates a nuisance and a worker safety hazard for nursery workers. The most effective treatment was pelargonic acid, a material that is already labeled for use in container nurseries and certified for use in organic agriculture. Apple replant diseases has been controlled in the past by methyl bromide. Researchers with USDA-ARS in Wenatchee have been investigating alternatives such as Brassica seed meals from Brassica juncea and Sinapsis albus. In the field, these treatments have resulted in plant performance equal to or better than telone-C17, a currently used fumigant. Researchers at WA continue to survey for cereal cyst nematode in eastern Washington. In Spring, 2014, an new species, H. filipjevi, was discovered in WA. Adapted material and regional nurseries are being screened in infested fields, and we have identified a cultivar, SY Steelhead, with resistance to H. filipjevi. Greenhouse screening methods are being developed. Anguina pacificae is a serious pathogen on annual bluegrass (Poa annua) on golf courses along the Northern California coast. At several golf courses a neem product registered for insect control in turf was applied from March to October in 14-day intervals to mitigate nematode-caused damage. During a 4-month trial at one of the golf courses there was no difference in A. pacificae population and turf health between the non-treated control and the bi-monthly neem product treatment. Reaction of Selected Pea Varieties to Root Rot Pathogens: A greenhouse test was conducted to evaluate the reaction of 23 commercially available or promising pea varieties to soilborne pathogens, especially Fusarium solani f. sp. pisi. Naturally infested soil was collected from a commercial field in western New York with a history of severe occurrence of pea root rot caused by F. solani f. sp. pisi and others too. The soil was mixed thoroughly and placed in 4-inch clay pots. Commercially-treated seeds of the selected varieties were planted at the rate of 7 seeds/pot and there were 4 replicates/variety. The pots were maintained in a greenhouse at 20-25 C and watered daily on as needed basis. Emergence counts was recorded two weeks after planting and the test was terminated at 30 days after planting. Roots were washed free of soil, blotted dry, plant weight recorded and root rot severity ratings were recorded on a scale of 1 (no visible disease symptoms, healthy) to 9 (>75% of root and stem tissues are affected and at a late stages of decay). None of the varieties tested were found to be resistant, but a number of these varieties showed tolerance to root pathogens of peas, as suggested by their lower root rot severity ratings, initial appearance of foliar symptoms and plant fresh weight. The varieties with the lowest root rot ratings were Grandy, Ricco, Hudson and Seminis 0969QH. Impact of Soil Health Management Practices on Root Rot Severity and Yield of Dry Beans: In 2014, dry beans were grown as the indexing crop in the 72 large plots of the long-term soil health site (14 acres) at the Gates Farm near Geneva, NY. The site was established in 2003 and consists of 18 treatments with 4 replications. The treatments include three tillage systems (no-till/ridge-till, strip-till, and conventional tillage), three cover crops (rye grain, hairy vetch, and no cover/fallow) and two rotations (one heavy with vegetables, whereas the other includes grain and forage crops and less vegetables). In 2014, the no-till plots in rotation 1 (heavy with vegetables) was converted to ridge-till. Biomass of the cover crops was recorded on May 19 and 20, 2014; plots were then mowed and were sprayed with the herbicide ‘Round-up” on June 4th. On June 13, the tillage plots were prepared and all the plots were planted to dry bean (CLRK) using a 2-row Monosem planter. A complete fertilizer blend (10-10-10, NPK) was banded at planting at 350 lbs./A. All the plots were sprayed with Dual Magnum (1.67 pt/A) pre-emergence and then again with Outlook (0.98 lb./A) on July18th. Emergence was recorded on July 25 and 20 plants/treatment/replicate were collected on August 19 for root rot severity evaluations on a scale of 1 (healthy) to 9 (most severe symptoms and at late stages of decay). Plots were harvested on September 25 and 26 and seed weight was recorded.. Tillage practices affected both the root rot severity ratings and yield of dry bean seeds. Root rot severity ratings were highest on plants in the conventional-till plots, whereas those on plants in the other tillage systems exhibited significantly lower ratings. Highest seed weight obtained was that in the strip-till systems and lowest was surprisingly in the ridge-till plots. Root health rating were lower and seed weight higher in the diversified rotation as compared to those of the strict vegetable rotation, although the difference were not significant. In contrast, the cover crop treatments did not affect root rot severity rating, but seed yield was highest in the vetch plots. Conducted experiments on grower’s farm in Maryland to evaluate the efficacy of biocontrol Coniothyrium minitans (Contans WG) on white mold of lima bean. Objective 4. Publication list covers all of the extension talks, publications, workshops and other outreach activity in more detail. In 2014, researchers from WA have presented over 20 extension talks, 7 field days and workshops/clinics and 6 special consultations (du Toit). Paulitz provided consultation on a regular basis for the WSU Disease Diagnostic Clinic. ARS Root Disease and Biological Control Research Unit continues to provide outreach to K-12 to Native Americans, including the Colville Confederated Tribes, the Spokane Tribe, and the Kalispell Tribes. ARS and WSU sponsored 8 senior high interns in Summer, 2014. We are presently supervising 9 graduate students at WSU and one PhD and 1 MSc student at Stellenbosch University in South Africa and one PhD student at Ankara University in Turkey. Researchers in California have presented several extension talks, field days and workshops (see below). They are supervising one graduate and 1 undergraduate student and one postdoctoral researcher. Researchers in Maryland are supervising one postdoctoral student and two graduate students. Researchers in Oregon have maintained two websites and published an open-access online journal for technology transfer to stakeholders: Forest Phytophthoras of the World http://www.forestphytophthoras.org/ Online Phytophthora Course: Training for Nursery Growers https://pace.oregonstate.edu/catalog/phytophthora-training-nursery-growers Forest Phytophthoras http://journals.oregondigital.org/ForestPhytophthora/issue/archive

Publications

Peer-reviewed Beltran-Garcia, M., White, J. F., Prado, F. M., Prieto, K. R., Yamaguchi, L. F., Torres, M. S., Kato, M. J., Medeiros, M. H. G., and Di Mascio, P. 2014. Nitrogen acquisition in Agave tequilana from degradation of endophytic bacteria. Scientific Reports 11/2014; 4:6938. Benecke, S., Jeske, D.R., Ruegger, P., and Borneman, J. 2013. Bayes neutral zone classifiers with applications to nonparametric unsupervised settings. Journal of Agricultural, Biological, and Environmental Statistics 18:39-52. du Toit, L.J., Derie, M.L., and Alcala, A.C. 2014. First report of Pythium sulcatum causing cavity spot in processing carrot crops in the Columbia Basin of Washington State. Plant Disease 98:427. Dunn, A. R., Bruening, S. R., Grünwald, N. J., and Smart, C. D. 2014. Evolution of an experimental population of Phytophthora capsici in the field. Phytopathology 104:1107-1117. Dunn, A.R., Lange, H.W., and Smart, C.D. 2014. Evaluation of commercial bell pepper cultivars for tolerance to Phytophthora blight. Plant Health Progress 15:19-24. Guarnaccia, V., Hansen, Z.R., Aiello, D., Smart, C.D., and Polizzi, G. 2015. First detection of root rot and foliar blight on Pittosporum (Pittosporum tenuifolium) caused by Pythium irregulare in Italy. Journal of Phytopathology in press. Henkels, M.D., Kidarsa, T.A., Shaffer, B.T., Goebel, N.C., Burlinson, P., Mavrodi, D.V., Bentley, M.A., Rangel, L.I., Davis II, E.W., Thomashow, L.S., Zabriskie, T.M., Preston, G.M., Loper, J.E. 2014. Pseudomonas protegens Pf-5 causes brown blotch symptoms on mushroom due to the production of antifungal metabolites. Molecular Plant-Microbe Interactions. 27(7):733-746. Hewavitharana, S. S., Ruddell, D., and Mazzola, M. 2014. Carbon source-dependent antifungal and nematicidal volatiles derived during anaerobic soil disinfestation. Eur. J. Plant Pathol. 140:39-52. Himmelstein, J. C., Maul, J., and Everts, K. L., 2014. Impact of five cover crop green manures and Actinovate on Fusarium wilt of watermelon. Plant Disease, 98: in press. (doi: http://dx.doi.org/10.1094/PDIS-06-13-0585-RE) Huang, Y.T., Yang, J., Chrobak, M. and Borneman, J. 2014. PRISE2: Software for designing sequence-selective PCR primers and probes. BMC Bioinformatics 2014, 15:317. Jones, L.A., Worobo, R.W. and Smart, C.D. 2014. Plant pathogenic oomycetes, Escherichia coli, Salmonella spp. frequently found in surface water used for irrigation of fruit and vegetable crops in New York State. Applied and Environmental Microbiology 4814-4820. Kandel, S.L., Smiley, R.W., Garland-Campbell, K., Elling, A.A., Abatzoglou, J., Huggins, D., Rupp, R., Paulitz, T.C. 2013. Relationship between climatic factors and distribution of Pratylenchus spp. in the dryland wheat-production areas of eastern Washington. Plant Disease. 97(11):1448-1456. Leuchtmann, A., Bacon, C. W., Schardl, C. L., White, J. F. and Tadych, M. 2014. Nomenclatural realignment of Neotyphodium species with genus Epichloe. Mycologia 04/2014; 106(2): 202-215. Liu, Y., de Bruijn, I., Jack, A., van der Voort, M., Drynan, K., van den Berg, A., van West, Pl, Thoen, E., Kdaar, I., Sandoval-Sierra, J., Dieguez-Uribeondo, J., Mendes, R., Mazzola, M., and Raaijmakers, J. 2014. Deciphering microbial landscapes of fish eggs to mitigate emerging diseases. ISME Journal: doi:10.1038/ismej.2014.44 Marzano, S.L., Wander, M.M, Villamil, M.B. Ugarte, C.M., Zaborski, E.R., and Eastburn, D.M. 2014. Organic amendment and transitional cropping system effects on crop diseases. Agronomy Journal. (in press) doi:10.2134/agronj2013.0189 Mazzola, M., and Hewavitharana, S. 2014. Carbon source-dependent volatile production and ASD efficacy for suppression of apple root pathogens. Acta Horticulturae 1044:209-214. Mazzola, M., and Strauss, S. L. 2014. Replant disease control and system resilience to pathogen re-infestation in response to Brassica seed meal amendment. Acta Horticulturae. 1044:105-112. Mazzola, M., Hewavitharana, S. and Strauss, S. L. 2015. Brassica seed meal soil amendments transform the rhizosphere microbiome and improve apple production though resistance to pathogen re-infestation. Phytopathology (accepted). Muramoto, J., Shennan, C, Baird, G., Zavatta, M., Koike, S. T., Bolda, M. P., Daugovish, O., Dara, S. K., Klonsky, K. and Mazzola, M. 2014. Optimizing anaerobic soil disinfestation for California strawberries. Acta Horticulturae 1044:215-220. Okubara, P.A., Dickman, M.B., Blechl, A.E. 2014. Molecular aspects of controlling the soilborne necrotrophic pathogens Rhizoctonia and Pythium. Plant Science. Available: http://dx.doi.org/10.1016/j.plantsci.2014.02.001. Okubara, P.A., Schroeder, K.L., Abatzoglou, J.T., Paulitz, T.C. 2014. Agroecological factors correlated to soil DNA concentrations of Rhizoctonia in dryland wheat production zones of Washington State. USA. Phytopathology. 104(7):683-691. Patzek, L.J., du Toit, L.J., Paulitz, T.C., Jones, S.S. 2013. Stunting of onion in the Columbia Basin of Oregon and Washington caused by Rhizoctonia spp. Plant Disease. 97(12):1626-1635. Poole, G.J., Smiley, R.W., Walker, C., Huggins, D., Rupp, R., Abatzoglou, J., Garland-Campbell, K., Paulitz, T. C. 2013. Effect of climate on the distribution of Fusarium spp. causing crown rot of wheat in the Pacific Northwest of the United States. Phytopathology. 103(11):1130-1140. Ruegger, P.M., Clark, R.T., Weger, J.R., Braun, J., and Borneman, J. 2014. Improved resolution of bacteria by high throughput sequence analysis of the rRNA internal transcribed spacer. J. Microbiol. Methods. 105:82-7. Schillinger, W.F., Paulitz, T.C. 2014. Natural suppression of Rhizoctonia bare patch in a long-term no-till cropping systems experiment. Plant Disease. 98(3):389-394. Shennan, C., Muramoto, J., Lamers, J., Mazzola, M., Rosskopf, E., Kokalis-Burelle, N., Momma, N., Butler, D., and Kobara, Y. 2014. Anaerobic soil disinfestation for soil borne disease control in strawberries and vegetable systems: Current knowledge and future directions. Acta Horticulturae 1044:165-175. Shi, Z., Balogh-Brunstad, Z., Grant, M., Harsh, J., Gill, R., Thomashow, L.S., Donalkova, A., Stacks, D., Letourneau, M., Keller, C. K. 2014. Cation uptake and allocation by red pine seedlings under cation-nutrient stress in a column growth experiment. Plant and Soil. 378(1-2):83-98. Stanghellini, M., Mohammadi, J. Adaskaveg, and H. Forster. 2014. Pythium brassicum: A novel host family-specific root pathogen. Plant Disease: (accepted for publication on May 17, 2014: article in First Look). Stanghellini, M., Mohammadi, M. and Adaskaveg, J. 2014. Effect of soil matric water potentials on germination of ascospores of Monosporascus cannonballus and colonization of melon roots by zoospores of Olpidium bornovanus. Eur. J. Plant Pathol. 139:387-392. Stanghellini, M.E., Mohammadi, M., Mathews, D.M., and Adkins, S. 2014. First report of vine decline of mature watermelon plants caused by Olpidium bornovanus. Plant Disease 98:852. Summers, C.F., Park, S. Dunn, A.R., Rong, X., Everts, K.L., Kleinhenz, M.D., McSpadden Gardener, B., and Smart, C.D. 2014. Fungal and oomycete pathogen detection in the rhizosphere of organic tomatoes grown in cover crop-treated soils. Applied Soil Ecology 80:44-50. Summers, C.F., Park, S. Dunn, A.R., Rong, X., Everts, K.L., Kleinhenz, M.D., McSpadden Gardener, B., and Smart, C.D. 2014. Fungal and oomycete pathogen detection in the rhizosphere of organic tomatoes grown in cover crop-treated soils. Applied Soil Ecology 80:44–50. Summers, C.F., Park, S., Dunn, A.R., Rong, X., Everts, K.L., Meyer, S.L.F., Rupprecht, S.M., Kleinhenz, M.D., McSpadden Gardener, B., and Smart, C.D. 2014. Multi-State field trials demonstrate infrequent and site-specific effects of a single season of mixed-species cover crops on productivity and disease severity in tomato. Applied Soil Ecology 77:51-58. Summers, C.F., Park, S., Dunn, A.R., Rong, X., Everts, K.L., Meyer, S.L.F., Rupprecht, S.M., Kleinhenz, M.D., McSpadden Gardener, B., and Smart, C.D. 2014. Single season effects of mixed-species cover crops on tomato health (cultivar Celebrity) in multi state field trials. Applied Soil Ecology 77:51-58. Tadych, M., Bergen, M. S., and White, J. F. 2014. Epichloë spp. associated with grasses: new insights on life cycles, dissemination and evolution. Mycologia 04/2014; 106(2): 181-201. Tanaseichuk, O., Borneman, J., and Jiang, T. 2014. Phylogeny-based classification of microbial communities. Bioinformatics 30:449-56. White, J. F., Torres, M. S., Sullivan, R. F., Jabbour, R. E., Chen, Q., Tadych, M., Irizarry, I., Bergen, M.S., Havkin-Frenkel, D., and Belanger, F. C. 2014. Occurrence of Bacillus amyloliquefaciens as a systemic endophyte of vanilla orchids. Microscopy Research and Technique DOI: 10.1002/jemt.22410. White, J. F., Torres, M. S., Somu, M. P., Johnson, H., Irizarry, I., Chen, Q., Zhang, N., Walsh, E., Tadych, M., and Bergen, M. 2014. Hydrogen peroxide staining to visualize intracellular bacterial infections of seedling root cells. Microscopy Research and Technique. 05/2014; DOI: 10.1002/jemt.22375 Yang, M.-M., Wen, S.-S., Mavrodi, D.V., Mavrodi, O.V., von Wettstein, D., Thomashow, L.S., Guo, J.-H., and Weller, D.M. 2014. Biological control of wheat root diseases by the CLP-producing strain Pseudomonas fluorescens HC1-07. Phytopathology. 104(3):248-256. Yin, C.T., Hulbert, S.H., Schroeder, K.L., Mavrodi, O., Mavrodi, D., Dhingra, A., Schillinger, W.F., Paulitz, T.C. 2013. Role of bacterial communities in the natural suppression of Rhizoctonia solani bare patch disease of wheat (Triticum aestivum L.). Applied and Environmental Microbiology. 79(23):7428-7438. Zhu, Y., Shin, S., Lu, J., Fazio, G., and Mazzola, M. 2015. Transcriptional regulation of ethylene and jasmonate mediated defense response in apple (Malus domestica) root during Pythium ultimum infection. Horticulture Research (accepted). Books and book chapters Becker, J.O. 2014. Citrus Pest Management: Nematodes. In: UC Citrus Production Manual, eds. L. Ferguson, E. E. Grafton-Cardwell. Univ. of Calif. Agric. and Nat. Resour. publication 3539 pp. 303-306. Becker, J.O. 2014. Plant Health Management: Crop Protection with Nematicides. In: Neal Van Alfen, editor-in-chief. Encyclopedia of Agriculture and Food Systems, Vol. 4, San Diego: Elsevier, pp. 400-407. Chincholkar, S., Thomashow, L.S. 2013. Microbial Phenazines: Biosynthesis, Agriculture and Health. Springer. 248 p. Mathews, D.M., J.O. Becker, and S. Tjosvold. 2014. Plant Diseases. Chapter 13. In Newman, J. (ed) Container Nursery Production and Business Management Manual. Univ. of Calif. Agric. and Nat. Resour. Publication 3540. Richmond, CA. pp.178-200. Thomashow, L.S. 2013. Phenazines in the environment: microbes, habitats, and ecological relevance. Pp 199-216 In: Chincholkar, S. and Thomashow, L., editors. Microbial phenazines: biosynthesis, agriculture and health. London, Springer. p. 199-216 Extension and Technical Bulletins and Popular Press Becker, J.O., A. Ploeg, and J. Nunez 2014. Management of root-knot nematodes with novel nematicides. California Tomato Research Institute 2013 Annual Report 92-98. Becker, J.O., and J. Borneman 2014. Biological, Biorational and Chemical Population Suppression of the Sugar Beet Cyst Nematode. 2013 Report to the California Sugar Beet Industry. 3 pp. du Toit, L.J., Derie, M.L., and Waters, T.D. 2014. 2013 Carrot cavity spot Serenade Soil trial. Research report submitted to Dean Christie, Bayer CropScience, in Jan. 2014. 6 pp. du Toit, L.J., Derie, M.L., and Waters, T.D. 2014. 2013 Onion pink root Serenade Soil efficacy trial in Pasco, Washington. Research report submitted to Dean Christie, Bayer CropScience, in Feb. 2014. 5 pp. du Toit, L.J., Derie, M.L., Holmes, B.J., and Youngquist, C.P. 2014. Effect of Proline and a biosolids compost on Fusarium and Verticillium wilts in a spinach seed crop, 2013. Plant Disease Management Reports 8:V280. du Toit, L.J., Sharma-Poudyal, D., Knerr, J., and Paulitz, T. 2014. Mycorrhizae in onion bulb production in the Columbia Basin. Pp. 7-8 in: 2014 WSU Onion Cultivar Demonstration & Field Day handouts. Washington State University, Pullman, WA. du Toit, L.J., Sharma-Poudyal, D., Paulitz, T., Hamm, P., and Eggers, J. 2014. Effect of deep vs. shallow tillage on onion stunting caused by Rhizoctonia solani AG 8 and onion bulb yield. Pp. 9-10 in: 2014 WSU Onion Cultivar Demonstration & Field Day handouts. Washington State University, Pullman, WA. Everts, K.L. 2014. Problematic Pathogens. American Vegetable Grower Magazine. Dec. 2014. Sharma-Poudyal, D., Eggers, J., Paulitz, T.C., Hamm, P., and du Toit, L.J. 2014. Effect of deep vs. shallow tillage on onion stunting and onion bulb yield, 2012. Plant Disease Management Reports 8:V306. Sharma-Poudyal, D., Paulitz, T.C., Linderman, R.G., and du Toit, L.J. 2014. Effect of arbuscular mycorrhizal fungi on onion growth and onion stunting caused by Rhizoctonia solani, 2013. Plant Disease Management Reports 8:V305. Stoven, H. and Parke, J. 2014. Nasty Nostoc. Digger 58:25-29. Meeting presentations and proceedings Abawi, G. S., Moktan, K.Stewart, C., Hadad, R., Jones, L. and Smart, C. 2014. Updating the status of the re-emerging and damaging bloat nematode on garlic: Proceedings of the NED-APS meeting in Portsmouth, NH during October 29-31, 2014. Becker, J.O. 2014. Observations on nematode-suppressive soils leading to IPM approaches. Proceedings of 6th International Congress of Nematology, 48. Borneman, J. 2014. "Utilizing the Endophytic Phytobiome to Develop Effective and Sustainable HLB Management Strategies." Presented at the W3147 Annual Meeting, October 24, 2014, Mission Inn, Riverside, CA. Collins, B.D., du Toit, L.J., Westerveld, S.M., and McDonald, M.R. Suppression of Fusarium wilt of spinach with chemical and biological fumigants. VIII International Symposium on Chemical & Non-Chemical Soil & Substrate Disinfestation. 13-18 July 2014, Turin, Italy. Poster presentation. Everts, K. L. 2014. Cover crops induce general suppression of watermelon Fusarium wilt in the Mid-Atlantic. 2014 Watermelon Research & Development Working Group Annual Meeting. (In conjunction with the Southern Region of the American Society for Horticultural Sciences Annual Meeting.) Dallas, TX. 02/01/2014 Funahashi, F. and Parke, J. 2014. Effects of soil water potential and diurnal temperature fluctuation on survival of soilborne Phytophthora ramorum and Phytophthora pini inoculum. ASA, CSA, & SSSA International Annual Meeting, Nov. 2-5, Long Beach, CA. Funahashi, F. and Parke, J. 2014. Modeling soil solarization and biocontrol of soilborne Phytophthora spp. in container nurseries. Eighth International Symposium on Chemical and Non-Chemical Soil and Substrate Disinfestation, ISHS, July 13-17, Torino, Italy. Gond, S. K., Bergen, M. S., Helsel, Z., Torres, M. S., and White, J. F. 2014. Rhizobacterium Pantoea agglomerans enhances salt stress tolerance of tropical corn (Zea mays indurata). 5th ASM Conference on Beneficial Microbes (Sept. 27-30) in Washington, DC. Li, H-Y., Soares, M. A., Torres, M. S., Bergen, M., and White, J. F. 2014. Endophytic bacterium, Bacillus amyloliquefaciens, in ornamental Hosta cultivar enhances plant resistance to insects. 5th ASM Conference on Beneficial Microbes (Sept. 27-30, 2014) in Washington, DC. Meyer, S.L.F., Zasada, I.A., Rupprecht, S.M., Hooks, C.R.R., Morra, M.J., Everts, K.L. 2014. Mustard seed meal amendments for suppression of Meloidogyne incognita on tomato. Annual Meeting of the American Phytopathological Society. Minneapolis, MN. Parke, J. and Funahashi, F. Solarization as a potential method to disinfest nursery soil contaminated by Phytophthora species. Mar. 11-13, 2014. 60th Annual Conference on Soilborne Plant Pathogens. Dominican University, San Rafael, CA. Contributed talk. Parke, J. L. 2014. A systems approach for managing Phytophthora diseases in horticultural nurseries. Special Session: A Systems Approach for Microbe Management: From Food Safety to Plant Health. APS-CPS Annual Meeting, St. Paul, MN Aug. 9-14. Invited talk. Paulitz, T. C. 2014. The First meeting of the Pacific Coast Research Conference on Control of Soil Fungi: Ripples in a Pond. Joint Meeting of the 60th Annual Conference on Soilborne Pathogens, San Rafael, California, March 11-14, 2014 Raudales, R. E., Parke, J. L., and Fisher, P. R. 2014. Chlorine efficacy to control Phytophthora nicotianae in solutions containing peat particles or nitrogen salts. ASHS. Reed-Jones, N.L., Marine, S.C., Everts, K.L., Micallef, S.A. 2014. Evaluating the effect of cover crops on the survival and growth dynamics of bacterial indicators in soil and on cantaloupes grown organically. BARC-UMD Symposium on "Organic Production: Food, Health and Ecosystems" November 13th, 2014 Shennan, C., Muramoto, J., Zavatta, M. and Mazzola, M. 2014. Non-fumigant approaches for controlling Fusarium wilt and charcoal rot of strawberry. Pages 11.1-11.4 in Proceedings, International Conference on Methyl Bromide Alternatives. MBAO, Fresno, CA Soares, M. A., Li, H., Bergen, M. and White, J. F. 2014. Endophytic colonization of invasive Hedera helix L. by plant growth-promoting bacterium Bacillus amyloliquefaciens. 5th ASM Conference on Beneficial Microbes (Sept. 27-30, 2014) in Washington, DC. Soares, M. A., Li, H., Bergen, M., and White, J. F. 2014. Endophytic colonization of invasive Hedera helix L. by plant growth-promoting bacterium Bacillus amyloliquefaciens. 5th ASM Conference on Beneficial Microbes (Sept. 27-30, 2014) in Washington, DC. Thompson, A., Garland, Campbell, K. Paulitz, T. and Smiley, R. 2014. Rooting out defense mechanisms in wheat against plant parasitic nematodes. American Society of Plant Biologists Conference. July 12-16, Portland, Oregon. Witte, H., J. Yang, J. Borneman, J. Smith Becker, and J.O. Becker 2014. Assessment of soils for the presence of the nematophagous fungus Dactylella oviparasitica by a PCR-based strategy. Proceedings of 6th International Congress of Nematology, 49. Zavatta, M., Shennan, C., Muramoto, J., and Mazzola, M. 2014. Evaluating C-sources for anaerobic soil disinfestation. Pages 12.1-12.4 in Proceedings, International Conference on Methyl Bromide Alternatives. MBAO, Fresno, CA Abstracts Becker, J.O. 2013. Disease protection against sedentary plant parasitic nematodes through combination products with agrochemical and biological control agents. J. Nematology 45: 282. Collins, B.D., McDonald, M.R., du Toit, L.J., and Westerveld, S. 2014. Identifying spinach cultivars with reduced susceptibility to Fusarium wilt. Phytopathology 104: presentation at the APS-Canadian Phytopathological Society Annual meeting, 9-13 Aug. 2014, Minneapolis, MN. Eberlein, C., Vidal, S., J.O. J.O. and Westphal, A. 2013. Population density suppression of Globodera pallida in a multi-year microplot trial with potato monoculture. Journal of Plant Diseases and Protection 120:142. Knerr, J., Sharma-Poudyal, D., Paulitz, T., and du Toit, L.J. 2014. Evaluation of arbuscular mycorrhizal fungi (AMF) in conventional and organic onion production in the Columbia Basin, and the potential use of AMF to reduce the impact of soilborne pathogens of onion. WSU Center for Sustaining Agriculture & Natural Resources (CSANR) BIOAg Symposium “Saving Nature and Improving Agriculture: Where does Nature’s Wisdom Lie?”, 28 Oct. 2014, Pullman, WA. Manning-Thompson. Y., Pumphrey, M., Garland-Campbell, K., and Paulitz, T. 2014. Screening locally adapted spring wheat lines for resistance to cereal cyst nematode. 2014 Dryland Field Day Abstracts. Dept. of Crop and Soil Sciences Technical Report 14-1. Pg. 68. McFarland, C., Huggins, D., Brown, T., Schroeder, K., Koenig, R., Blackburn, J., Carpenter-Boggs, L. and Paulitz, T. C. 2014, Remediation of stratified soil acidity through surface application of lime in no-till cropping systems. 2014 Dryland Field Day Abstracts. Dept. of Crop and Soil Sciences Technical Report 14-1. Pg. 34. Okubara, P., A., Schroeder, K. L., and Paulitz, T. C. 2014. Distribution of Rhizoctonia bare patch and root rot in Eastern Washington and relation to climatic variables. 2014 Dryland Field Day Abstracts. Dept. of Crop and Soil Sciences Technical Report 14-1. Pg. 63. Schillinger, W., Paulitz, T., Schibel, J., Jacobsen, J. and Schoftoll, S. 2014. Management of fresh wheat residue for irrigated winter canola production. 2014 Dryland Field Day Abstracts. Dept. of Crop and Soil Sciences Technical Report 14-1. Pg. 54. Stanghellini, M.E., Mohammadi, J. and Stowell, L. 2014. Desbotaca arida: a culturable mycorrhizal ascomycete with a wide host range including Brassica from desert habitats. Phytopathology (abstract) in press. Extension Talks/Field Days/Workshops/Consultations Aujia, I. S., Lawrence, N. C., Taylor, L. B, Paulitz, T. C., and Burke, I. C.. 2014. Rhizoctonia Bare Patch and the Green Bridge. Regional Approaches to Climate Change Annual Conference: Regional Approaches to Climate Change. Kennewick, Washington, March 5-7, 2014. Becker, J.O. 2014. "Seed treatments against plant parasitic nematodes: When a little goes a long way." 6th International Congress of Nematology, Cape Town, South Africa, May 4-9, 2014 (invited symposium talk in session Nematicides). Becker, J.O. 2014. "Citrus nematode, hands-on learning." UC Riverside Citrus Day for Professional Industry members. UCR Agricultural Operations, Riverside, CA, Feb 20, 2014 (invited presentation) Becker, J.O. 2014. "Observations on nematode-suppressive soils leading to IPM approaches." 6th International Congress of Nematology, Cape Town, South Africa, May 4-9, 2014. (invited symposium talk in session Biological Control). Becker, J.O. 2014. "Plant Parasitic Nematodes in California Turf"University Extension Turf Management Certificate Course, 3 hr lecture (webinar), UC Riverside Extension, May 20, 2014, Riverside, CA. (invited presentation). Becker, J.O. 2014. "Population suppression of sugarbeet cyst nematodes."California Sugar Beet Industry Research Meeting, Holtville, CA, January 29, 2014. Becker, J.O. 2014. “How to address root knot nematode damage in melons?” Field day with company representatives, South Coast Research and Extension Center, Irvine, CA. September 9, 2014 Becker, J.O. 2014. “Efficacy of new nematicides” .Tomato field day with UCCE farm advisor Joe Nunez, Shafter, CA, September 18, 2014. ca 25 grower, industry personnel (Adama, Valent, DuPont), Press/Radio. (invited). Becker, J.O. 2014. “Everything you always wanted to know about turf grass nematodes and their control”.Turf & Landscape Field Day, AgOps, UC Riverside, September 11, 2014. (invited presentation). Becker, J.O. 2014. “Next-Generation Nematicides 25th Annual Fall Desert Crops Workshop 2014. El Centro, CA, November 13.” (invited presentation). Becker, J.O. 2014. “Root gall ratings and disease-related yield losses in tomatoes”.Field day, South Coast Research and Extension Center, August 15, 2014. Becker, J.O. 2014. “Symptom expressing and damage potential by root knot nematodes in carrots”. Field day, South Coast Research and Extension Center, August 20, 2014. Becker, J.O. 2014. ”Moving forward in nematode management while avoiding past mistakes” Processing tomato field day with UCCE farm advisor Joe Nunez, Shafter, CA (Kern County), Oct 14, 2014 (invited) Becker, J.O. 2014. Applied Nematology Workshop (1 1/2 days, together with Antoon Ploeg, UC Riverside), July 29/30/2014, UC Riverside/UC South Coast Research and Extension Center. Becker, J.O. 2014. Interview with Jan Sears (Assistant Metro Editor, The Press-Enterprise) about unmanned aerial systems for nematode surveys. UCR, Riverside, CA, Feb 7, 2014. Publication: The Press-Enterprise Feb 18, 2014, Section Local Extra - Southwest; Page B4 "Drones could give big lift to farmers." du Toit, L.J. 2013. Discussed seed crop disease research with Bjarne Hansen, Seed Production Manager for Vikima Seeds, Denmark, 11 Jul. 2013, Mount Vernon, WA. du Toit, L.J. 2014 WSU Extension Carrot Field Day, 15 Aug. 2014, Pasco, WA. Presented carrot disease management summary to growers, seed industry, and other carrot stakeholders (~30 people). du Toit, L.J. 2014 WSU Onion Field Day, Carr Farms, Pasco, WA, 28 Aug. 2014. Presented update on research projects on Rhizoctonia induced stunting in onion bulb crops, and mycorrhizae in onion crops. Field day attended by ~100 state/federal regulators, industry representatives, breeders, growers, consultants, researchers, & extension educators. du Toit, L.J. 2014 Washington Pest Control Tour of the Washington State Commission on Pesticide Registration, central WA, 28-31 July 2014. Presented on vegetable seed production and research needs, including pathology research, to ~60 federal/state legislators or staff, agricultural industry representatives, WA State Depts. of Agriculture, Ecology, and Labor & Industries; WSU CAHNRS administrators, National Marine Fisheries Service, US Environmental Protection Agency, etc. as part of a 3-day agricultural tour of central WA du Toit, L.J. 2014 WSU Mount Vernon NWREC Field Day. Presented updates on spinach and table beet seed crop disease research trials to ~100 growers, consultants, extension educators, researchers, WSDA and seed industry personnel along with reports from other faculty at the NWREC, and 2 MS students in my program. 11 Jul. 2014, Mount Vernon, WA. du Toit, L.J. 2014 WSU Vegetable Seed Field Day. Presented updates on brassica, beet, and spinach seed crop disease research and extension activities to ~40 vegetable seed growers, seed company production personnel, and research and extension faculty. 3-hour tour of field trials, 20 Jun. 2014, Skagit Valley, WA. du Toit, L.J. 2014. Allium, bean, & crucifer quarantines diseases in Washington: Do the current rules suffice? 21st Joint Meeting of the Washington State Crop Improvement Association/Washington North-Idaho Seed Association, 10-11 November 2014, Spokane, WA. du Toit, L.J. 2014. Black rot and white mold in brassica vegetable seed crops. Invited presentation and discussion with broccoli and cauliflower seed growers for Syngenta Seeds in the Western Cape, South Africa, 10 Mar. 2014, Lutzville, South Africa. (30 people) du Toit, L.J. 2014. Diagnosing diseases in the field. Invited presentation, Annual Basin Producers 2014 Pesticide Recertification Day, 17 Jan. 2014, Moses Lake, WA. (~200 people) du Toit, L.J. 2014. Does this product really work? Distinguishing sound science from hot air in product promotional materials. Invited presentation, Columbia Basin Crop Consultants Association 2014 Short Course, 15-16 Jan. 2014, Moses Lake, WA. (~80 people) du Toit, L.J. 2014. Does this product really work? Distinguishing sound science from hot air in product promotional materials. Columbia Basin Vegetable Seed Association Annual Meeting, 21 Jan. 2013, Moses Lake, WA. (~75 people) du Toit, L.J. 2014. Invited to lead a 3-hour discussion on disease and insect management in onion seed crops for the seed production team of JW Seeds, 13 Mar. 2014, Oudtshoorn, South Africa du Toit, L.J. 2014. Invited to lead a discussion on management of soilborne diseases of vegetables with the production team for a large, commercial, mixed vegetable farm, Laastedrif, in the Ceres region, Western Cape Province, South Africa, 11 Mar. 2014, Ceres, South Africa. du Toit, L.J. 2014. Invited to participate in a 4-hour workshop on disease and insect management in onion seed crops with the onion seed production team of Klein Karoo Seed Production, 12 Mar. 2014, Oudtshoorn, South Africa. Co-led the discussion with B. Wessels, consultant, ProCrop Trust. du Toit, L.J. 2014. Management of Botrytis in onion; and vascular wilts, leaf spots, and Phomopsis, a quarantine fungus, in spinach. Bejo Seeds, Inc. Invited presentation to the Bejo Seeds, Inc. International Sales and Production Meeting, 13 Jan. 2014, Mount Vernon, WA. (~25 managers, sales, & seed production employees of Bejo Seeds, Inc.) du Toit, L.J. 2014. Management of Fusarium and Verticillium wilts in spinach seed production: Research update. Puget Sound Seed Growers’ Association Annual Meeting, 20 Feb. 2014, Mount Vernon, WA. (~50 people) du Toit, L.J. 2014. Mycorrhizae and Fusarium basal rot in onion bulb crops. Two invited presentations and discussion with onion bulb growers and consultants in the Ceres and Kouebokkeveld regions of the Western Cape Province, South Africa, 11 March 2014, Ceres, South Africa. (40 people) du Toit, L.J. 2014. Organized and led multiple group discussions and research/extension planning on beet seed crop production in western WA in response to declining seed yields and quality over several years: 3.5 hour meeting on 31 Jan. (30 people), 1 hour meeting on 23 Apr. (40 people), 8 Jul. (invited Prof. Irwin Goldman, table beet breeder and Chair of Dept. of Horticulture, University of Wisconsin, to meet with beet seed growers and industry personnel, and tour beet seed crops and beds to review production practices; 25 people). du Toit, L.J. 2014. Soil health for disease suppression. Building Soils for Better Crops 2014 Conference, 10 Dec. 2014, Moses Lake, WA. du Toit, L.J. 2014. Sustainability of Organic Spinach. Invited to provide seed pathology expertise for a discussion with spinach growers, crop consultants, and spinach seed industry representatives (~65 people) on disease management in organic baby leaf spinach production in Yuma, AZ and Salinas, CA following extensive losses to damping-off, downy mildew, and leaf spots. Visited spinach crops and participated in 2-hour discussion. 8 Jan. 2014, Pivot Point Conference Center, Yuma, AZ. Sponsored by Gowan Co., Yuma, AZ; Bornt Family Farms, Holtville, CA; and United Vegetable Growers Cooperative, Salinas, CA. du Toit, L.J. 2014. White mold: Sclerotonia sclerotiorum. Invited presentation for the workshop ‘Managing Sclerotinia/White Mold in the Columbia Basin’, 19 March 2014, Moses Lake, WA. (90 people) du Toit, L.J. 2014.Onion mycorrhizae. Onion session of the Pacific Northwest Vegetable Association Annual Convention & Trade Show, 12-13 Nov. 2014, Kennewick, WA. du Toit, L.J. Invited to participate in an emergency meeting titled ‘Plant Disease Alert Meeting: Black Leg & Leaf Spots in Brassica, Mustard, & Radish Crops’ following a widespread epidemic of black leg and two new leaf spot diseases, white leaf spot and light leaf spot, in diverse brassica crops in the Willamette Valley in spring 2014. Spoke on black leg fungicide seed treatment research by my program and the WSDA Crucifer Quarantine rules. Other speakers were from Oregon Dept. of Agriculture and Oregon State University plant pathologists. Presentations and panel discussion with diverse brassica stakeholders, including proposed ODA rules to reduce the risk of further spread and introduction of these diseases. 18 Jun. 2014, Albany, OR. Also visited infected brassica crops in the Willamette Valley on 18-19 Jun. 2014. du Toit, L.J. Met with Western WA Small-Seed Advisory Committee (2 June 2014) and Columbia Basin Vegetable Seed Field Representatives Association (3 June 2014) to discuss: 1) the widespread epidemic of black leg of brassicas (caused by Phoma lingam) in the Willamette Valley of OR in spring 2014, a quarantine disease in northwestern WA; and 2) finding white rot in an onion seed crop (caused by Sclerotium cepivorum) in Grant Co. in May 2014, part of a 4-county quarantine area of WA for this disease. Presented information to growers and seed company field reps on these diseases, including management practices for reducing the risk of spread and establishment. With C. Ocamb at OSU, prepared a 2-page ‘Alert’ on black leg for widespread distribution among all brassica growers, seed dealers, seeed companies, etc. in the Pacific Northwest to reduce the risk of further spread of the pathogen. du Toit, L.J., and Price Youngquist, C. 2014. Biosolids compost use in vegetable seed crops, potatoes, and small grains. Invited presentation, Soil Quality Network 2014, 13 February 2014, Mount Vernon, WA. (~100 people) du Toit, L.J., and Waters, T. 2014. Carrot insect pests and diseases. Pest Management session of the Pacific Northwest Vegetable Association Annual Convention & Trade Show, 12-13 Nov. 2014, Kennewick, WA. Everts, K. L. 2014. Fusarium oxysporum f. sp. niveum on Watermelon: Developing a Sustainable Management Strategy. Salisbury University - Biological Sciences Seminars. Salisbury, MD. 2-20-2014 Mazzola, M. 2014. “Use of Cover Crops to Manage Soil-borne Diseases in Strawberry”, California Strawberry Commission Grower Meeting. December 11, 2014, Watsonville, CA. Mazzola, M. 2014. “Biologically-based soil-borne disease control strategies: Potential mechanisms of Action California Strawberry Commission, August 5, 2014, Watsonville, CA. Mazzola, M. 2014. “Managing soil microbes for enhanced orchard establishment and performance”, Washington Tilth 40th Celebration Conference, November 8, 2014, Vancouver, WA. Mazzola, M. 2014. How and why mustard seed meal and cover crops may be used to manage soil-borne diseases in strawberry, Strawberry Field Days, Watsonville, CA. “August 2, 2014, Watsonville, CA. Mazzola, M. 2014. Roots and Soil Biology: Managing the “microherd’ for maximum tree performance. Washington State Horticultural Society Annual Conference, December 3, 2014, Vancouver, WA. Mazzola, M. 2014.Practical Soil Health for Farmers, “Managing soil microbiology for disease control and system resilience”, Northwest Soil Quality Network 2014. Feb. 13, 2014, Mt. Vernon, WA. Paulitz, T. C. 2014. Fusarium crown rot- Management with Genetic Resistance. Washington Grain Commission Review, Pullman, WA, Feb 20, 2014. Paulitz, T. C. 2014. Updates in Wheat Disease Research, Garfield Grange, Colfax, Washington, January 25, 2014. Paulitz, T. C. 2014. Updates on Canola/Camelina Diseases. Washington State Biofuels Cropping Systems Meeting, Pullman, Washington February 21, 2014. Paulitz, T. C. 2014. Fusarium Diseases. Crop Diagnostic Clinic, Spillman Farm, Pullman, Washington, June 26, 2014 Paulitz, T. C. and Schillinger, W. 2014. Management of fresh wheat residues in irrigated winter canola. Washington State Department of Ecology, Ag Burning Task Force. Spokane, Washington. February 11, 2014 and June 10, 2014. Paulitz, T. C.2014. Management of Rhizoctonia diseases in the Pacific Northwest. Syngenta Seed Care Workshop, Spokane, Washington, February 3, 2014. Paulitz, T. C.2014. Research at USDA-ARS in Pullman, What’s New? Spokane Farm Forum, Ag Expo, Spokane, Washington, February 4, 2014. Paulitz, T.C. 2014. Rhizoctonia Diseases on Cereals and Rotation Crops: The Quest for Root Health. The 2014 Syngenta North American Root Health Forum. Palm Beach, FL. Oct. 20-21, 2014. Stanghellini, M. 2014. “Late season vine-decline: foes from below”. Western Watermelon Growers Association meeting in Las Vegas, Nevada, Jan. 17-19, 2104. Stanghellini, M. 2014. Desbotaca arida: a culturable mycorrhizal ascomycete with a wide host range including Brassica from desert habitats. APS Pacific Div . meeting in Bozeman, Montana. July 10, 2014. Stanghellini, M. 2014. Management strategies for soilborne root-infecting pathogens. Storkan-Hanes-McCaslin Foundation, June 30, 2014, San Marcos, California. Stanghellini, M. 2014. Plant diseases and their relationships with the environment. Botany and Plant Science 235 (Agroecology). April 28, 2014. UCR.

Impact Statements

Reduction in the use of telone for apple replant disease. Demonstration that biofumigation is as effective as chemical fumigation in long-term field experiments with apple replant disease and results in a long-term microbial shift. A Brassicaceae seed meal formulation was commercialized and is now in the process of seeking approval for use is a bio-pesticide (Farm Fuels Inc., Santa Cruz, CA).
A new tool for the management of cereal cyst nematode, which cannot be managed by chemicals. Identification of wheat varieties resistant to cereal cyst nematode, including SY Steelhead. These varieties can be used immediately to reduce the spread and impact of this new pathogen.
Greater understanding and exchange of information about the detection, identification and ecology of soilborne pathogens of wheat, barley and Brassicas and the control of root diseases via host genetic resistance, management practices and beneficial microbes that provide biocontrol. This information is disseminated through the many extension activities described below.
Knowledge about microbial endophytes that may be used to protect crop plants from disease. These isolates of endophytes will be patented and used to develop products to protect crop plants. This will also lead to an understanding of how plants use their microbiomes for defense and to enhance their nutritional status.
A new technique that will be used in further exploring the distribution of the biocontrol agent. Baiting D. oviparasitica with developing H. schachtii females improved PCR detection of the fungus in field soils.
Better management of the nematode Anguina on turf grass. Anguina turf trial demonstrated the need for efficacy monitoring and comparison to appropriate checks. This information has been disseminated through extension activities described below.
Demonstration that the use of cover crops in a corn:soybean rotation may be effective for reducing disease severity levels. Managing diseases, weed problems, and increasing soil health through the use of cover crops will increase the sustainability of the corn:soybean rotation system, and increase the profitability of soybean production by reducing yield losses resulting from disease problems.
Adding the population levels of the fungus Dactylella oviparasitica to cropping decision models. We anticipate this will lead to higher crop yields and profitability for the growers.
We developed PRISE2, a software program enabling the design of sequence-selective PCR primers and probes. This program has several features not present in any other program, enabling us to design tools to track and quantify specific bacteria that co-exist with thousands of other bacteria, which is a capability that has been lacking in this type of experimentation. This tool will enable us to track microorganisms in soil, which will allow us to identify and understand microorganisms involved in plant pathogen suppression.

Date of Annual Report: 01/27/2016

Report Information

Annual Meeting Dates: 12/04/2015 - 12/04/2015
Period the Report Covers: 10/01/2014 - 09/30/2015

Participants

Michael Anderson, Professor, Oklahoma State University

Jennifer Parke, Professor, Oregon State University

Jenifer McBeath, Professor, University of Alaska

Tim Paulitz, Professor, Washington State University

Tony Adesemoye, Assistant Professor, University of Nebraska

James Borneman, Professor, UC Riverside

Ole Becker, Extension Specialist, UC Riverside

Antoon Ploeg, Extension Specialist, UC Riverside

Fumi Funahashi, Postdoc, Oregon State University

Brief Summary of Minutes

Minutes of the 2015 Meeting of the Multistate Project W3147

December 4, 2015

Mission Inn, San Diego Room

Riverside, CA

Antoon Ploeg, Chair

James Borneman, Secretary

James Borneman, local arrangements

Members in Attendance:

Michael Anderson, Professor, Oklahoma State University

Jennifer Parke, Professor, Oregon State University

Jenifer McBeath, Professor, University of Alaska

Tim Paulitz, Professor, Washington State University

Tony Adesemoye, Assistant Professor, University of Nebraska

James Borneman, Professor, UC Riverside

Ole Becker, Extension Specialist, UC Riverside

Antoon Ploeg, Extension Specialist, UC Riverside

Fumi Funahashi, Postdoc, Oregon State University

The meeting started at 8:30am with the chair’s welcome and self-introduction of attendees.

The minutes from the 2014 meeting were approved.

December 2, 2016 was selected as the data for the next meeting, and the location was determined to be the Mission Inn, Riverside, CA.

James Borneman was selected as secretary for 2015.

No secretary for the 2016 meeting was selected.

Progress Reports:

Jenifer McBeath: “Antifreeze Protein of cold adapt Trichoderma atroviride from Alaska.”

James Borneman: Discussed the use of monitoring the population densities of the fungus Dactylella oviparasitica

Antoon Ploeg: “A field trial with the new nematicide Nimitz™ in sweet potato.” Also mapping breaking of resistance to rootknot nematodes in the central valley.

Ole Becker: “Efficacy of MeloCon (Purpureocillium lilacinum strain PL 251 syn. Paecillomyces lilacinum) on two root-knot nematode species. Ole also discussed use or Pasteuria penetrans as a biological control agent.

Tony Adesemoye: “Disease Suppressive Soils in Nebraska” and “Evaluation of Bacterial Biological Control Agents for Control of Root-knot Nematode Disease on Tomato.”

Mike Anderson: “Productivity Associated Rhizobacteria and Nitrogen Fertilization of Wheat.”

Fumi Funahashi: “Modeling Survival of Soilborne Phytophthora spp. and Characterizing Microbial Communities in Response to Soil Solarization and Biocontrol Amendment in Container Nursery Beds.”

Jennifer Parke: Discussed the use of solarization in field nursery setting to reduce weeds using anti-condensation plastic film.

Tim Paulitz: “Are bacterial and fungal communities affected by long-term no-till vs conventional tillage?” “Are bacterial communities affected by the widely used herbicide glyphosate?” “Discovery of Leptosphaeria maculans (Blackleg) and L. biglobosa on canola in the Pacific Northwest.”

Accomplishments

Objective 1 To identify and characterize new biological agents, naturally suppressive soils, cultural practices, and organic amendments that provide management of diseases caused by soilborne plant pathogens. CA - One of the long-term goals of the Borneman research program is to develop more sustainable strategies to manage soil-borne plant pathogens. To accomplish this, we are endeavoring to understand soils that naturally inhibit plant pests and disease, termed suppressive soils. Key steps in realizing the potential of these soils are to identify the causal organisms and then understand the agronomic and environmental factors that enable them to function.  Armed with such knowledge, it should be possible to develop effective and sustainable pest management strategies through the application of the organisms and through agronomic practices that influence their populations.  To date, we have identified several fungi involved in suppressing sugarbeet cysts nematodes (Dactylella oviparasitica and Fusarium oxysporum) and root-knot nematodes (Pochonia chlamydosporium and a Tetracladium sp.).  We have also identified new Dactylella oviparasitica phylotypes, which suggests that these fungi may represent a large group of potentially effective biological control agents, and which can be found worldwide.  In addition, we have determined that soils with no detectable Dactylella populations can harbor this fungus, and which can dramatically increase during one host cropping cycle.  This is a key finding, suggesting that standard methods for screen soils for putatively protective microorganisms will not work.  We have also presented a new approach and supporting data for using Dactylella population densities in planting decisions models. CA- Another long-term goal of the Borneman research program is to develop new methods that enable a greater understanding of the roles microorganisms play in processes such as nematode and replant disease. In prior research, we developed several molecular and computational methods that should facilitate a greater understanding of these phenomena. We are continuing these efforts by developing a high-throughput method for microbial community analyses, a software package for designing PCR primers and probes, and a statistical method for classifying soils (or other entities). IL- A recombinant strain of Sclerotinia sclerotiorum hypovirus 2 (SsHV2) was identified from a North American Sclerotinia sclerotiorum isolate from lettuce by high-throughput sequencing of total RNA. The assembled nucleotide sequence was up to 92% identical to two recently reported SsHV2 strains but contained a deletion near its 5′ terminus of more than 1.2 kb relative to the other SsHV2 strains and an insertion of 524 nucleotides that was distantly related to Valsa ceratosperma hypovirus 1. This suggests that the new isolate is a heterologous recombinant of SsHV2 with a yet-uncharacterized hypovirus. We named the new strain Sclerotinia sclerotiorum hypovirus 2 Lactuca (SsHV2L). Sclerotinia sclerotiorum isolate 328 was coinfected with a strain of Sclerotinia sclerotiorum endornavirus 1 and was debilitated compared to cultures of the same isolate that had been cured of virus infection by cycloheximide treatment and hyphal tipping. To determine whether SsHV2L alone could induce hypovirulence in S. sclerotiorum, a full-length cDNA of the 14,538-nt viral genome was cloned. Transcripts corresponding to the viral RNA were synthesized in vitro and transfected into a virus-free isolate of S. sclerotiorum, DK3. Isolate DK3 transfected with SsHV2L was hypovirulent on soybean and lettuce and exhibited delayed maturation of sclerotia relative to virus-free DK3, completing Koch's postulates for the association of hypovirulence with SsHV2L. ME- Short-term outcomes. Improved the understanding of the interaction of soilborne pathogen (Phytophthora erythrosetptica) and its host (potato), which may lead to a novel disease control strategies. Outputs: Processed 500 plant samples in the detection of potato soft rot pathogen. Supervised three graduate students, two undergraduate students and two visiting scholars. Published 4 papers in peer-reviewed journals, 11 in online journal, and 7 abstracts to conferences. Provided valid information of breeding lines in controlling three potato diseases. Activities: participated grand proposal and attended the post-award meetings in conducting the research of OREI projected funded. Presented in the National Potato Council conference in Wahsington DC in December. Presented in the First Soilborne Oomycete International Conference in Florida in December. Presented in three universities in China by invitation. Milestones: Accomplished for the second year of crop rotation study by November 2015.   NY- Change in a Phytophthora capsici population over time. To identify control strategies, it is important to know how a pathogen population in a field is changing over time. Sexual, endemic populations of the heterothallic Phytophthora capsici continue to devastate vegetable crops in the northeast. In many instances, flooding events introduced P. capsici into fields with no prior history of the pathogen. Common occurrence of both A1 and A2 mating types results in production of oospores, and consequently persistent, overwintering populations. Further, prior research in our lab provides evidence for localized populations, with little to no gene flow between fields in the northeast. To understand the dynamics of these isolated, sexual populations of P. capsici, a restricted access research farm in Geneva, NY, with no prior history of P. capsici, was inoculated in 2008 with two isolates of opposite mating type. Approximately, 50 isolates were sampled each year from 2009-13 from a variety of susceptible plant species. To parallel the field study, F1 single-oospore progeny were isolated from a cross performed in the lab between the same founding parents. These F1 provide a frame of reference for the field population in which generation and relatedness of isolates are unknown. Isolates were analyzed using genotyping-by-sequencing (GBS), which simultaneously identifies and scores single nucleotide polymorphism (SNP) markers, resulting in approximately 30,000 SNP markers distributed throughout the genome. Analysis of population structure with principal component analysis and genetic distance between isolates, show an increase in prevalence of clones with increasing year. Our results indicate that in initial years the population was defined by many unique individuals, but in later years was dominated by several clonal isolates. Preliminary analysis of individual heterozygosity, defined as percent heterozygous sites per individual, suggests that oospores formed in the founding year may contribute less to population structure over time. Here, individual heterozygosity is used as an indicator of inter-mating between related isolates, as heterozygosity is expected to decline with increased mating between closely related individuals (i.e., inbreeding). In addition, we provide further evidence that oospores are the sole source of overwintering inoculum for P. capsici, as the same genotype was never observed in multiple years. An analogous GBS approach was applied to 70 isolates sampled from a P. capsici population in a newly infested grower's field of cucurbits. Our assessment of population structure and genetic distance in this population show that there were several founding isolates, with asexual reproduction resulting in the proliferation of a subset of these founders. The ratio of A1:A2 mating types in this population was approximately 1:1 for both clone-corrected and non-clone-corrected data sets. Once a field is infested with both mating types of P. capsici, it is currently unfeasible to eradicate the pathogen. Thus, it is essential to understand both the founding and long-term trajectories of P. capsici populations to improve management strategies. NJ- We identified a number of endophytic microbes in English ivy, corn, and Hosta that suppress damping off and other seedling diseases in the plants. NY- Spatiotemporal variation in genetic and phenotypic characteristics of Sclerotinia sclerotiorum populations. Sclerotinia sclerotiorum isolates were collected from white mold-affected plants within 10 fields in 2014 (n = 200) and 24 fields between 1982 and 2008 (n = 36) across New York State, USA. Spatiotemporal variation in genotype using eight microsatellite loci, mycelial compatibility, and aggressiveness and growth rate were quantified. Twenty-eight multilocus genotypes (MLGs) were detected with one MLG present at high incidence across all fields in 2014. The same MLG was also prevalent among isolates collected between 1982 and 2008. Four MLGs were identified in the isolates collected between 1982 and 2008 that were not detected in 2014. Values for standardized Index of Association (d) values within fields suggested that S. sclerotiorum populations were predominantly clonal. Analysis of molecular variance and minimum spanning networks did not detect significant within or between field spatial structure to the population in 2014. However, there was evidence of low but significant levels of differentiation between two fields (Nei’s FST = 0.13). Mycelial compatibility groupings were mostly consistent with MLGs. Variation in aggressiveness within a cut-stem greenhouse bioassay on snap bean was observed both among MLGs and within a single MLG. Significant variation was detected in mycelial growth rate on artificial media, but was not correlated with aggressiveness. These findings may assist in informing the effective deployment of chemical-based management strategies for white mold and support the selection of representative isolates for resistance screening to local populations. WA- Using pyrosequencing, we compared fungal communities (family level) between long-term no-till and conventionally tilled soils, in side-by side plots, over two years in two locations in WA and ID. Fungi such as Trichocladium and Exophiala were more dominant in no-till systems, while Cladosporium, Ulocladium and Cryptococcus were dominant in conventionally tilled systems. In the latter, fresh wheat residues incorporated may favor fast-growing pioneer colonists like Cladosporium.  With no-till systems, the only carbon source is wheat roots which may be colonized by Trichocladium, initially as an endophyte. WA- Draft genome sequences of 11 strains of biocontrol bacteria of Pseudomonas that inhibit plant-parasitic nematodes and fungal soilborne pathogens were obtained. Comparative genomics and bioinformatics is ongoing to discover bacterial loci encoding anti-pathogen metabolites and deduced chemical structures of metabolites. This information will be used by agri-products companies (e.g., AGPW LLC) for formulating candidate control compounds. WA- We are investigating the effect of glyphosate on microbial communities in a dryland wheat cropping system. We collected soil from 4 growers, including no-till fields with a long history of glyphosate use vs. adjacent fields with native grassland and no history of herbicide use. The soils were planted in a greenhouse with wheat, and half treated with glyphosate over 6 planting cycles. DNA was extracted from rhizosphere and bulk soil, and pyrosequenced using bacterial primers. We did not find any major shift in bacterial populations caused by glyphosate use, but farm location, cropping system, and proximity to roots had significant effects. Two families, Sphingomonadaceae and Sphingobacteriaceae, had OTUs reduced by glyphosate. The experiment will be repeated. WA- VegelysTM, a commercially-available Allium-based biocontrol formulation marketed by Phyto Auxillium, Grez Neuville, France, controls bacteria and fungi on plant surfaces, such as seed, without negative effects on germination or growth. We found it also inhibits growth of the soilborne plant pathogens Rhizoctonia solani AG 8, Fusarium culmorum, F. pseudograminearum, Pythum ultimum and Gaeumannomyces graminis var. tritici on agar plates. We are determining if the formulation can be applied to soil or seed for seedling protection (greenhouse and field). This information will be useful to growers if disease suppression can be obtained at economically feasible rates. WA-Bacteria of the genus Pseudomonas provide a wealth of biocontrol potential but are less stable on the shelf and less persistent in the field than Bacillus or Trichoderma. Cellulose-based media are being explored to aid in storage, delivery and application of biocontrol strains of Pseudomonas in the greenhouse and field. WA- Researchers at USDA-ARS, in collaboration with Joint Genomics Institute, are testing new constructs of Pseudomonas that produce novel phenazine compounds using in vitro and greenhouse assays against Rhizoctonia and Gaeumannomyces. WA- Onions are dependent on arbuscular-mycorrhizal fungi (AMF) for uptake of P. However, soils are often fumigated before planting onion crops in the Columbia Basin, which may eliminate this beneficial symbiosis. However, a survey indicated that AMF are similarly present in organic and conventional onion bulb crops. Next-generation sequencing was used to identify AMF genera in both systems, with greater abundance of Glomerales in the organic vs. conventional fields, and greater abundance of Glomus spp. Similar assessments are being done with 4 pairs of onion fields, with one field in each pair fumigated and the other not fumigated with methyl bromide in fall 2014, prior to planting onion seed in spring 2015. With colleagues at Univ. California-Santa Cruz and the California Strawberry Commission, Mazzola demonstrated efficacy of anaerobic soil disinfestation for soilborne disease control in strawberry production systems.   Objective 2 To understand how microbial populations and their gene expression are regulated by the biological (plants and microbes) and physical environment and how microbes influence disease.   CA- A novel bioassay for efficacy and quality control of nematode egg-parasitic microorganisms was developed. Two products based on Purpureocillium lilacinum were evaluated with various fungal propagule density (cfu) and at different temperatures. Outcomes: Establishment of a standardized procedure for quality control for egg-parasitic biocontrol products against plant parasitic nematodes. For the tested products, efficacy was best at 23˚C with no difference among amendment levels between 5x105 and 5x107 cfu/g soil. Outputs: Information on efficacy of commercial P. lilacinum products at various soil temperatures. Activities: Procedure will be use to evaluate other microbial nematophagous strains or products obtained from producers or collaborators. Milestones: Information on usefulness of procedure will be generated with a range of nematophagous microorganisms within a two-year project period.   IL- A project evaluating the effect of cover crop and tillage treatments on disease suppression in a following soybean crop was initiated in 2014 and continued in 2015. Treatments include several fall planted cover crops including cereal rye, hairy vetch, hairy vetch/rye mix, mustard, and a fallow control, superimposed on tillage treatments of ridge-till and chisel plowing. Root of soybean seedlings were evaluated for disease, and foliar and root diseases were evaluated when the plants were nearing maturity. Soybean roots, bulk soil, and rhizosphere soil were collected from plants grown in cover crop tillage experimental plots when the soybean plants were in the seedling stage. DNA was extracted from the roots and rhizosphere soils taken from the fallow and rye plots in both the ridge-till and chisel-plow treatment main plots. DNA extracts from the 2014 season were assayed for soybean pathogen populations using qPCR, and they were also used to evaluate microbial community structures using a method involving Illumina sequencing. Due to cost constraints, only the DNA extracts from selected treatments were evaluated. DNA was extracted for PCR amplification, targeting 16s bacteria and archaeal, ITS, ammonia monooxygenase, nitrous oxide reductase, and ammonia generating nitrite reductase genes, for subsequent high throughput sequencing. Results from the 2014 experiment showed no significant differences in microbial populations associated with the cover crop treatments. However, there were several notable differences with the tillage treatments. Chisel plowed plots had increased levels of the genera, Verrucomicrobia, Glomeromycota, Proteobacteria, and Actinobacteria. Ridge tilled plots show increased levels of Streptophyta, Firmicutes, and Crenarchaeota. These differences show that there are several factors that play important roles in shaping the structure of microbial disease suppressive communities as related to SDS. We are in the process of extracting DNA from the 2015 soil samples. Once this is done a similar process will be used to compare the effects of treatments on microbial community structure. Unusually wet soil conditions during the 2015 growing season resulted in fairly high levels of sudden death syndrome in all treatment plots, with no discernable effect of cover crop or tillage treatments on disease severity levels. NJ- We examined organic acid production in cranberry and showed its role in suppression of virulence in fruit rot pathogens in plants. Organic acids are also present in roots of plants and would be expected to suppress virulence of soil pathogens. NY- Host resistance is a key management strategy for root and crown rot caused by Phytophthora capsici in pepper. An isolate of P. capsici constitutively expressing a gene for green fluorescent protein was used to investigate pathogen interactions with roots and crowns of a susceptible (Red Knight) and two resistant (Paladin and CM-334) pepper cultivars. Zoospores attached to and germinated on roots of all three cultivars equally well at 30 and 120 minutes post inoculation (pi), respectively. At 3 days pi, significantly more secondary roots had lesions on Red Knight plants compared to Paladin and CM-334 plants, although hyphae had colonized tips of at least some secondary roots of all cultivars. By 4 days pi, necrotic lesions had formed on the primary root of Red Knight, but not Paladin and CM-334 plants. Although hyphae were visible in the crown tissue of Red Knight plants by 3 days pi, no hyphae were observed in crowns of Paladin or CM-334 plants, even after 10 days pi. These results were published in Phytopathology in 2015.  Future studies will look at resistance and susceptibility in other hosts such as eggplant.   OR- Parke and Funahashi investigated effects of soil solarization and application of a biocontrol agent on soil microbial communities. Illumina Miseq amplicon sequencing was used to compare solarized and non-solarized soil, alone or with subsequent amendment of Trichoderma asperellum (TA). Field trials were conducted in San Rafael, CA and in Corvallis, OR. Soil samples from three different depths (5, 15, and 30 cm) were taken before soil solarization, after solarization, and after TA application. The V4 region of the 16S rRNA genes of prokaryotes and the ITS1 region of fungal DNA were sequenced. Communities were clearly separated by site. Soil solarization caused significant changes in both communities, but affected fungal communities more strongly than prokaryotic communities by reducing species richness and diversity. Moisture content was a significant factor affecting the prokaryotic community but not the fungal community. Application of TA did not have a significant effect on microbial communities even though T. asperellum was detected in TA plots. The change in relative abundance of individual taxa as well as taxonomic groups reflects their sensitivity to heat. This study revealed the potential use of the technique to evaluate the susceptibility of each taxon to solarization and biocontrol amendment. WA- We are investigating how temperature and water potential affect the growth and reproduction of Rhizoctonia and Fusarium, two pathogens causing root and crown rot of wheat. Fusarium culmorum and F. pseudograminearum are capable of growth at -7 mPa, while Rhizoctonia solani AG-8 was restricted beyond -1 mPa. F. culmorum, F. pseudograminearum, and R. solani AG-8 grew optimally at 20-25oC, while R. oryzae had optimal growth at 30oC.  This information is needed to model distribution of these pathogens under future climate change scenarios.   Objective 3. Implement sustainable management strategies for soilborne pathogens that are compatible and integrated with good soil health practices.   NM- A field experiment was conducted to evaluate the efficacy of a top performing mustard cover crop and mustard seed meal used alone or in combination on Verticillium wilt in a commercial field with history of Verticillium wilt. Seed of mustard cover crop cultivar 'Caliente 199' Brassica juncea was planted in early spring 2014. Eight weeks after planting, the cover crop was disked and incorporated into soil. Mustard seed meal (Brassica juncea Ida Gold) was then applied with a manure spreader at two rates (0, 1265, and 1680 kg/ha) before seed beds were shaped. The green chile cultivar, AZ-1904 (Capsicum annuum) was direct seeded three weeks later. Disease assessment was conducted in fall 2014. Average disease incidence was between 20 and 30% across the three treatments. Mustard cover crops and mustard seed meals may serve as viable components of soil and disease management in a chile rotation system. NM- A study was conducted under controlled-environment to assess the effects of extracts from pecan shell and husk on the production of sporangia and chile pepper infection by Phytophthora capsici. Aqueous extracts of 5, 10, 15 and 20% were prepared from ground tissues. Mycelium plugs from a culture of P. capsici were placed in filter-sterilized aqueous extracts of 0 (control), 5, 10, 15, and 20% and incubated at 26C in the dark for 72 h. Sporangia production was less in pecan husk than in pecan shell extract. Zoospores of P. capsici were added to extracts, and placed on a rotary shaker for24, 48 and 72 h. Population of P. capsici was significantly reduced in pecan tissue extracts at 72 h after incubation. In growth chamber studies, seedlings of a chile pepper cultivar susceptible to P. capsici were subirrigated with infested tissue extracts. Disease severity was significantly reduced when chile plants were subirrigated with infested extracts compared to plants subirrigated with infested water. Results indicate that pecan shell and husk tissues may be used in the treatment of irrigation water to reduce the activity of P. capsici in chile pepper. NM- In another controlled-environment study, four fungicides (fluopyram, penthiopyrad fluazinam and boscalid) were evaluated for efficacy against mycelium growth and pigmentation, and sclerotia and oxalic production by Sclerotinia sclerotiorum, a pathogen that has been recently reported on peanut and cabbage in New Mexico. Results showed that fluopyram and boscalid reduce mycelium growth compared to control, fluazinam, and penthiopyrad when PDA was amended with these fungicides. Sclerotia and mycelium pigmentation were noticed on control PDA, and PDA amended with fluazinam and penthiopyrad. However, none of the fungicides inhibited oxalic acid production based on the presence of yellow halo on bromophenol blue plates. NM- Mexico State University Peanut Breeding Program and were evaluated for resistance to isolates of Sclerotinia sclerotiorum found in New Mexico. Plants at the three-to-five fully expanded leaf stage were inoculated with S. sclerotiorum and placed in a humidity box and maintained in a 20 C growth chamber. First symptoms of infection occurred within one week post-inoculation on several varieties. Two weeks following inoculation, all varieties were dead with the exception of one experimental line, which showed no symptoms or signs of infection. These results suggest that this experimental line can be used in peanut breeding program to develop varieties resistant to S. sclerotiorum. NY- Development of species-specific PCR tests for detection and quantification of Meloidogyne hapla. The Northern root-knot nematode, Meloidogyne hapla, is a significant soilborne pathogen of vegetables grown in the United States.  Effective management of plant parasitic nematodes relies on the accurate identification and timely quantification of populations prior to planting.  Prediction of damage from soilborne diseases may be substantially improved by the provision and adoption of pre-plant soil tests which utilize DNA sequences that are highly sensitive and specific to the pathogen of interest.  Here, PCR primers were designed around variable regions of the 16D10 effector gene in M. hapla and assayed for specificity against 13 plant parasitic nematodes using qualitative PCR.  The primers developed in this study were shown to be highly specific to M. hapla. These primers will be utilized in future quantitative PCR tests for quantification of population densities in soil and to assess the risk of crop damage or loss due to M. hapla. OR- Parke’s group conducted research on the sustainable management strategy of soil solarization to disinfest raised beds of plant pathogens and weeds. Four different types of clear plastic film were evaluated in a commercial tree seedling nursery in Oregon for their effects on soil temperature, weed emergence, and certain soilborne pathogens. Films treated with an anti-condensation (AC) coating achieved higher soil temperatures and greater reduction of weeds as compared to films without the AC coating. In the most effective treatment, there were 363 or 124 cumulative hours >40° C at soil depths of 5 and 15 cm, respectively. Fall weed emergence was reduced from 22 plants per sq. ft. in the nonsolarized control to ≤0.3 plants per sq. ft. in AC-solarization treatments.  Soil populations of Fusarium spp. and Pythium spp. at both 5 and 15 cm depths were also reduced by solarization with AC films. WA- In spring 2014, a new species, H. filipjevi, was discovered in eastern WA. Adapted wheat material and regional nurseries are being screened in infested fields, and we have identified a cultivar with resistance to H. filipjevi, SY Steelhead, along with 9 other adapted varieties/lines.  Greenhouse screening methods have been developed, and we started screening winter wheat varieties. We found soft white and hard red varieties with resistance to H. filipjevi. WA- As part of an effort to identify the extent of infestation of H. filipjevi, we developed methods to identify species from DNA isolated from a single cyst. We extended the survey throughout Whitman Co., and so far have found that H. filipjevi is restricted to southern Whiteman Co., with H. avenae in other sites. About 15-30% of the fields surveyed in the Palouse are infected by cereal cyst nematode. WA- Synthetic wheat lines with partial resistance to Rhizoctonia root rot have been developed. ARS scientists in Pullman, WA, in collaboration with scientists at Washington State University, used field and greenhouse screens to identify five synthetic wheats with consistent partial resistance to Rhizoctonia root rot. The wheats represent new, non-genetically modified resources for breeders and growers to manage Rhizoctonia root rot. WA- Growth chamber trials with AMF fungi were used to assess 4 commercial AMF products for enhancing onion growth. MYKOS Gold showed the most significant and most consistent benefit of the products, followed by MYKE Pro (now AGTIV) and BioTerra Plus. No effects were observed with MycoApply. However, the benefits of AMF were negated in soil with higher levels of P. Field trials are being planned with onion and carrot growers in the Columbia Basin to evaluate some of these products in 2016. WA- In conjunction with colleagues at Univ. California-Santa Cruz and the California Strawberry Commission, demonstrated efficacy of anaerobic soil disinfestation for soil-borne disease control in strawberry production systems.   Objective 4. Provide outreach, education, extension and technology transfer to our clients and stakeholders- growers, biocontrol industry, graduate and undergraduate students, K-12 students and other scientists.   ME- Short-term outcomes. Helped Maine potato growers understand and make better strategies in soft rot disease control. Outputs. Attended four conferences and meetings in helping potato growers understand the outbreak of potato soft rot and management. Activities. Participated in a Field Day for Maine potato growers in August. NJ- Five graduate students in my lab are working on projects related to objectives of this multistate project. We published 9 articles and gave 3 invited lectures at international meetings reporting research results from this project. NY- Disease management strategies for Phytophthora capsici In 2015, Smart gave 5 talks to growers, extension educators and industry representatives on strategies to control Phytophthora blight. These included talks at the NY state fruit and veg expo, talks at winter grower meetings in western and eastern NY, and summer twilight meetings.  Additionally, Smart presented a webinar during the winter of 2015 to beginning vegetable growers. Undergraduate research experience. The Plant Pathology and Plant-Microbe Biology Section on the Geneva Campus of Cornell University established a summer scholars program to increase the involvement of undergraduate researchers in applied agricultural sciences. Smart is the director of this program for all 4 departments on the campus.  In 2015, 26 students presented posters at the end of the program.  Each summer, several students are involved with projects that are part of the W3147 multi-state project.  During the summer of 2015, a student in the Smart lab worked on Phytophthora capsici studying the population biology and evolution of the pathogen.  Outreach to K-12 students. We have continued our outreach program to third-grade students in the Geneva City School District (Geneva, NY). Part of this outreach includes a summer science camp, where students study different aspects of food production utilizing a garden that they plant at their school.  One week of the 5-week program focuses on the importance of healthy soil to producing healthy vegetables. NY-Outreach activities on sustainable disease management Pethybridge gave multiple extension presentations of a range of topics (white mold = 3; general plant pathology and soilborne disease management = 8; lima bean diseases = 1; root crop diseases = 4; garlic diseases = 2) during 2015. These presentations included grower meetings organized by Cornell Cooperative Extension throughout NY.  Undergraduate research experience. Two undergraduate students were involved in the study quantifying the spatiotemporal variation in genotypic and phenotypic variation in Sclerotinia sclerotiorum. An additional undergraduate student was involved in the development of the species-specific PCR tests for root-knot nematodes.  Two of these students were participants in the Summer Scholars Program within The New York State Agricultural Experiment Station, Cornell University OR- Parke presented a webinar on a systems approach to producing healthy container-grown plants for 110 growers of California native plants for restoration purposes. A presentation on the effects of soil solarization will be made to the Shade Tree Growers Association meeting in Aurora, OR on Dec. 10, 2015. The nursery grower (Sam Doane, J. Frank Schmidt and Son, Co.) who collaborated with Parke and provided the site for the field trials will make the presentation. Parke will present findings to nursery growers, agricultural professionals, and extension personnel at the Western Disease Conference in Portland on Jan. 14, 2016. An article on solarization will also be published in the Feb. 2016 issue of Digger, the nursery grower magazine published by the Oregon Association of Nurseries (circulation 8,000). Parke also created an educational poster to show nursery workers how to recognize disease symptoms and reduce disease spread.  The bilingual color poster (19” x 27”) was distributed at no charge to 1000 nurseries by the Oregon Department of Agriculture plant inspectors. Activities: Conducted and analyzed lab and field experiments. Mentored 3 graduate students and 2 undergraduate students. Mentored 2 postdoctoral associates. Events: Conducted a training session via webinar and a talk for growers. Services: Advised several nurseries on disease management issues. Products: Produced an educational poster and distributed it to 1000 nurseries. Maintained two websites [http://forestphytophthoras.org/] and [http://horticulture.oregonstate.edu/content/phytophthora-online-course-training-nursery-growers]. Edited and published an online journal [http://journals.oregondigital.org/ForestPhytophthora/issue/archive]. Graduated 1 Ph.D. student, 1 M.S. student, and advised 1 undergraduate senior thesis.   WA- In 2015, researchers from WA presented over 30 extension talks, field days, workshops/clinics and special consultations in relation to soilborne diseases. Paulitz provided consultation on a regular basis for the WSU Disease Diagnostic Clinic and for cereal and oilseed growers to diagnose diseases, and du Toit diagnosed 98 vegetable and seed crop samples. ARS Root Disease and Biological Control Research Unit continues to provide outreach to K-12 Native Americans, including the Colville Confederated Tribes, the Spokane Tribe, and the Kalispell Tribes. Examples of these activities include: 1) monthly visits to Nespelem Elementary School and Pascal Sherman Indian School on the Colville Reservation to present STEM modules, October 2014 - May 2015; 2) molecular biology, biochemistry and engineering training for 13 summer high school interns (June- July 2015) in ARS and WSU labs; and placement of underserved WSU undergraduates as laboratory assistants in ARS and WSU labs. In addition, ARS scientists taught a special workshop on diseases to Native American high school students from Idaho for the REACCH HOIST program, June, 2015, at the WSU Spillman Farm. du Toit toured Northwest Indian College in Dec. 2015 and gave a guest lecture on careers in plant sciences, and is participating in the PNW COSMOS grant with the NSF AGEP to recruit Native American students into STEM graduate studies. du Toit mentored a graduate student, Carmody, for a 4-hour workshop on diagnosing plant diseases given to ‘Growing Veterans’ (military veterans program) and Latino farmers on 7 Nov. 2015 in Skagit Valley. WA- The USDA ARS wheat group presently is supervising 6 graduate students at WSU. Mazzola is mentoring three PhD students at WSU, one PhD and 1 MSc student at Stellenbosch University in South Africa, and one MSc student at CalPoly San Luis Obispo. du Toit is chairing the committee of 4 MS students at WSU, and is on another 4 PhD committees at WSU and 1 MS committee at the University of Guelph, with projects on soilborne plant pathogens. WA- Paulitz was the main coordinator and organize of Joint Meeting of the 61st Annual Conference on Soilborne Pathogens, Riverside, California, March 23-26, 2015. This annual meeting attracts almost 100 industry, academic, government, regulatory, and student attendees.

Publications

Peer-reviewed   Adrienne M. Gorny, A.M., Kikkert, J.R., Dunn, A.R., Dillard, H.R., Smart, C.D., and Pethybridge, S.J. (2015) Tan spot of lima bean caused by Boeremia exigua var. exigua in New York State, USA. Canadian Journal of Plant Pathology in press Alhawatema, M. S., Sanogo, S., Baucom, D. L., and Creamer, R. 2015. A search for the phylogenetic relationship of the Ascomycete Rhizoctonia leguminicola using genetic analysis. Mycopathologia 179:381-389. Bacon, C. and White, J. 2015. Functions, mechanisms and regulation of endophytic and epiphytic microbial communities of plants. Symbiosis DOI: 10.13140/RG.2.1.1956.9124 Dunn, A.R. and Smart, C.D. (2015) Interactions of Phytophthora capsici with resistant and susceptible pepper roots and stems. Phytopathology 105:1355-1361. Dyer, A.T., Al-Khafaji, R. T., Tyler, L., Paulitz, T. C., Handoo, Z. A., Skantar, A. and Chitwood, D. 2015. First report of the cereal cyst nematode Heterodera filipjevi on winter wheat in Montana. Plant Disease 99:1188. Fry, W.E., Birch, P., Judelson, H., Grunwald, N.J., Danies, G., Everts, K.L., Gevens, A.J., Gugino, B., Johnson, D.A., Johnson, S.B., McGrath, M., Myers, K.L., Ristaino, J.B., Secor, G.A., and Smart, C.D. (2015) Five Reasons to consider Phytophthora infestans a re-emerging pathogen. Phytopathology 105:966-981. Funahashi, F., and J. L. Parke. 2015. Effects of soil solarization and Trichoderma asperellum on soilborne inoculum of Phytophthora ramorum and Phytophthora pini in container nurseries. Plant Dis. doi:10.1094/PDIS-04-15-0453-RE. Gatch, E.W., and du Toit, L.J. 2015. A soil bioassay for predicting the risk of spinach Fusarium wilt. Plant Disease 99:512-526. Gebremariam, E. S., Karakaya, A., Erginbass-Orakci, G., Dababat, A. A., Sharma-Poudyal, S. and Paulitz, T. C. 2015. First report of Fusarium redolens causing crown rot of wheat (Triticum spp.) in Turkey. Plant Disease 99:1280. Gond, S. K., Bergen, M.S., Torres, M. S. and White. J. F. 2015. Effect of bacterial endophyte on expression of defense genes in Indian popcorn against Fusarium moniliforme. Symbiosis DOI: 10.1007/s13199-015-0348-9 Gond, S. K., Torres,M. S.,Bergen, M. S., Helsel, Z and White, J. F. 2015. Induction of salt tolerance and up-regulation of aquaporin genes in tropical corn by rhizobacterium Pantoea agglomerans. Letters in Applied Microbiology doi:10.1111/lam.12385. Guarnaccia, V., Hansen, Z.R., Aiello, D., Smart, C.D., and Polizzi, G. (2015) First detection of root rot and foliar blight on Pittosporum (Pittosporum tenuifolium) caused by Pythium irregulare in Italy. Journal of Phytopathology 163:411-414. Jiao, X., Lu, X.,  Chen, A. J., Luo, Y., Hao, J. J. and Gao, W. 2015. Effects of Fusarium solani and F. oxysporum infection on the metabolism of ginsenosides in American ginseng roots. Molecules 20: 10535-10552. Jones, L.A., Saha, S., Collmer, A., Smart, C.D., and Lindeberg, M. (2015) Genome assisted development of a diagnostic protocol for distinguishing high virulence in Pseudomonas syringae pv tomato strains. Plant Disease 99:527-534. Kowalski, K. P., Bacon, C., Bickford, W., Braun, H., Clay, K., Leduc-Lapierre, M., Lillard, E., McCormick, M., Nelson, E.,  Torres, M.  White, J. and Wilcox, D. A. 2015. Advancing the science of microbial symbiosis to support invasive species management: A case study on Phragmites in the Great Lakes. Frontiers in Microbiology 01/2015; 6:95. DOI: 10.3389/fmicb.2015.00095 Lange, H.W. Tancos, M.A., Carlson, M.O., and Smart, C.D. (2016) Diversity of Xanthomonas campestris isolates from symptomatic crucifers in New York State. Phytopathology in press. Li, H-Y., Soares, M., Torres, M., and White, J. 2015. Endophytic bacterium, Bacillus amyloliquefaciens, enhances ornamental hosta resistance to diseases and insect pests. Journal of Plant Interactions 10:224-229 Li, Q., Wu, L., Hao,J.,  Luo, L.,  Cao, Y., and  Li, J.. 2015. Biofumigation on post-harvest diseases of fruits using a new volatile-producing fungus of Ceratocystis fimbriata. PLoS ONE 10(7): e0132009. doi:10.1371/journal.pone.0132009. Lu, X. H. Jiao, X. L., Hao, J. J., Chen, A. J., and Gao, W. W.. 2015. Characterization of resistance to multiple fungicides in Botrytis cinerea population from Asian ginseng in Northeastern China. European Journal of Plant Pathology. DOI 10.1007/s10658-015-0786-5. Manici, L. M., Kelderer, M., Caputo, F., and Mazzola, M. 2015. Auxin-mediated relationships between apple plants and root inhabiting fungi: impact on root pathogens and potentialities of growth-promoting populations. Plant Pathology 64:843-851. Marzano, S.L, Villamil, M.M, Wander, M.B., Ugarte, C.M., Wen, L. Eastburn, D.M. 2015. Organic transition effects on soilborne diseases of soybean and populations of Pseudomonadaceae. Agronomy Journal 107:1087-1097. Marzano, S.L., Hobbs, H.,Nelson, B., Hartman, G., Eastburn, D.M., McCoppin, N., and Domier, L. 2015. Transfection of Sclerotinia sclerotiorum with in vitro transcripts of a naturally occurring interspecific recombinant of Sclerotinia sclerotiorum hypovirus 2 significantly reduces virulence of the fungus. Journal of Virology, Volume: 89   Issue: 9   Pages: 5060-5071 Mazzola, M., Hewavitharana, S. and Strauss, S. L. 2015. Brassica seed meal soil amendments transform the rhizosphere microbiome and improve apple production though resistance to pathogen re-infestation. Phytopathology 105:460-469. Nesemann, K., Braus-Stromeyer, S.A., Thuermer, A., Daniel, R., Mavrodi, D.V., Thomashow, L.S., Weller, D.M., Braus, G.H. 2015. Draft genome sequence of the phenazine-producing Pseudomonas fluorescens strain 2-79. Genome Announcements. Poudyal, D., Paulitz, T.C., Du Toit, L.J. 2015. Evaluation of onion genotypes for resistance to stunting caused by Rhizoctonia solani AG 8. HortScience.50:551-554. Poudyal, D., Paulitz, T.C., Du Toit, L.J. 2015. Stunted patches in onion bulb crops in Oregon and Washington: Etiology and yield loss. Plant Disease.99:648-658. Poudyal, D., Paulitz, T.C., Porter, L., Du Toit, L.J. 2015. Characterization and pathogenicity of Rhizoctonia and Rhizoctonia-like spp. from pea crops in the Columbia Basin of Oregon and Washington. Plant Disease. 99:604-613. Sanogo, S., and Zhang, J. 2015. Resistance sources, resistance screening techniques and disease management for Fusarium wilt in cotton. Euphytica. Online. DOI 10.1007/s10681-015-1532-y. Sanogo, S., Lujan, P., and Baucom, D. 2015. First report of Sclerotinia sclerotiorum on cabbage in New Mexico. Plant Dis.http://dx.doi.org/10.1094/PDIS-12-14-1328-PDN Soares, M., Li, H-Y, Bergen, M. and White, J. 2015. Functional role of an endophytic Bacillus amyloliquefaciens in enhancing growth and disease protection of invasive English ivy (Hedera helix L.). Plant and Soil DOI: 10.1007/s11104-015-2638-7 Song, C., Mazzola, M., Cheng, X., Alexandrov, T., Dorrestein, P., Watrous, J., van der Voort, M., and Raaijmakers, J. 2015. Molecular and chemical dialogues in bacteria-protozoa interactions. Scientific Reports 5:12837. Summers, C.F., Adair, N., Gent, D.H., and Smart, C.D. (2015) Pseudoperonospora cubensis and P. humuli detection using species-specific probes and high definition melt curve analysis. Canadian Journal of Plant Pathology 37:315-330. Summers, C.F., Gulliford, C.M., Carlson, C.H., Lillis, J.A., Carlson, M.O., Cadle-Davidson, L., Gent, D.H., and Smart, C.D. (2015) Identification of genetic variation between obligate plant pathogens Pseudoperonospora cubensis and P. humuli using RNA sequencing and genotyping-by-sequencing. PLoS ONE 10(11): eD143665. DOI: 1D.1371/journal.pone.D143665. Tadych, M., Vorsa, N., Wang, H., and White, J. 2015. Interactions between cranberries and fungi: The proposed function of organic acids in virulence suppression of fruit rot fungi. Frontiers in Microbiology 6:835, DOI: 10.3389/fmicb.2015.00835 Tancos, M.A., Lange, H.W., and Smart, C.D. (2015) Characterizing the genetic diversity of the New York Clavibacter michiganensis subsp. michiganensis population. Phytopathology 105:169-179. Tewoldemedhin, Y. T., Lamprecht, S. C., and Mazzola, M. 2015. Rhizoctonia anastomosis groups associated with diseased rooibos seedlings and the potential of compost as soil amendment for disease suppression. Plant Disease 99:1020-1025. White, J. F., Chen, Q., Torres, M., Mattera, R., Irizarry, I.,Tadych, M., and Bergen, M. 2015. Collaboration between grass seedlings and rhizobacteria to scavenge organic nitrogen in soils. AoB PLANTS 01/2015; doi: 10.1093/aobpla/plu093 Zhang, J., Sanogo, S, Ma, Z., and Qu, Y. 2015. Breeding, genetics, and quantitative trait locus mapping for Fusarium wilt resistance in cotton. Crop Sci doi:10.2135/cropsci2015.01.0056 Zhang, J., Yu, J., Pei, W., Li, X., Said, J., Song, M., and Sanogo, S. 2015. Genetic analysis of Verticillium wilt resistance in a backcross inbred line population and a meta-analysis of quantitative trait loci for disease resistance in cotton. BMC Genomics 16: 577. Zhang, X., Dong, B., Zhou, H., Xie, J., and Hao, J. 2015. First report of Rhizoctonia solani AG4-HG-I infecting sugar beet in Inner Mongolia of China. Plant Disease 99:1185. DOI: 10.1094/PDIS-12-14-1326-PDN. Zhou, W-A., White, J., Soares, M., and Li, H-Y. 2015. Diversity of fungi associated with plants growing in geothermal ecosystems and evaluation of their capacities to enhance thermotolerance of host plants. Journal of Plant Interactions DOI: 10.1080/17429145.2015.1101495   Books and book chapters   Theses Allen, N. M. 2015. Soil quality assessment of Willamette Valley soils and root colonization potential by arbuscular mycorrhizal fungi. M.S. thesis, Oregon State University. 107 pp.   Funahashi, F. 2015. Modeling survival of soilborne Phytophthora spp. and characterizing microbial communities in response to soil solarization and biocontrol amendment in container nursery beds. Ph.D. thesis, Oregon State University. 180 pp.   Extension and Technical Bulletins   Becker, J.O., A. Ploeg, and J. Nunez 2014. Control of root-knot nematodes in fresh carrot production. Annual Report California Fresh Carrot Advisory Board, 67-73. Becker, J.O., A. Ploeg, and J. Nunez 2014. Evaluation of new nematicides against root-knot nematodes in processing tomato production. Annual Report California Tomato Research Institute, 94-100. du Toit, L.J. and Derie, M.L. 2015. 2014 Onion pink root Serenade Soil efficacy trial in Connell, Washington. Research report submitted to Dean Christie, Bayer CropScience, Feb. 2015. 4 pp. du Toit, L.J., Derie, M.L., and Holmes, B.J. 2015. 2014 Carrot cavity spot Serenade Soil trial. Research report submitted to Dean Christie, Bayer CropScience, Feb. 2015. 7 pp. du Toit, L.J., Waters, T., and Reitz, S. 2015. Internal dry scale and associated bulb rots: Bane of the 2014 Pacific Northwest onion season. Onion World May/June 2015:4-7. Hao, J. J., H.H. Jiang, X. Zhang, N. Marangoni, E. Giggie. 2015. Evaluation of fungicide programs for powdery scab and late blight control in potatoes, Presque Isle, ME, 2015. Hao, J. J., H.H. Jiang, X. Zhang, N. Marangoni, E. Giggie. 2015. Evaluation of oxathiapiprolin and other products for pink rot and Pythium leak control in potatoes, Presque Isle, ME, 2015. Hao, J., X.M. Zhang, H.H. Jiang, N.F. Marangoni, E. Giggie. 2015. Evaluate the efficacy of Emesto Silver plus Reason as a seed treatment for control of pink rot in potato, Presque Isle, ME, 2015. Hao, J. J. H.H. Jiang, N. Marangoni, X. Zhang, E. Giggie. 2015. Evaluation of breeding lines on pink rot resistance, Presque Isle, ME, 2015. Hao, J. J. H.H. Jiang, N. Marangoni, X. Zhang, E. Giggie. 2015. Evaluation of soil fumigation on soilborne disease of potatoes, Presque Isle, ME, 2015. Hao, J. J., H.H. Jiang, X. Zhang, N. Marangoni, E. Giggie. 2015. Evaluation of Emesto Silver and Manzate in treatment for soilborne disease control in potatoes, Presque Isle, ME, 2015. Hao, J. J., N. Marangoni, H.H. Jiang, X. Zhang, E. Giggie. 2015. Evaluation of oxathiapiprolin, chlorothalonil and other premixes for late blight control in potatoes, Presque Isle, ME, 2015. Hao, J. J.,X.M. Zhang, H.H. Jiang, N.F. Marangoni, E. Giggie. 2015. Evaluate the efficacy of A12946B as a seed treatment for control of pink rot in potato, Presque Isle, ME, 2015. Hao, J., X.M. Zhang, H.H. Jiang, N.F. Marangoni, E. Giggie. 2015. Evaluate the efficacy of Double Nickel LC for control of pink rot in potato, Presque Isle, ME, 2015. Hao, J., X.M. Zhang, H.H. Jiang, N.F. Marangoni, E. Giggie. 2015. Evaluate V10365 for control of pink rot in potato, Presque Isle, ME, 2015. Kikkert, J., Pethybridge, S. J., Dunn, A. R., and MacNeil, C. 2014. What to do after a bad Sclerotinia white mold season?  Cornell Cooperative Extension, Cornell Vegetable Program.  Veg Edge 10:1-3. Parke, J. L. and Stoven, H. 2015. Management of the cyanobacterium Nostoc in horticultural nurseries. PNW Plant Disease Management Handbook. <a href="http://pnwhandbooks.org/plantdisease/pathogen-articles/pathogens-common-many-plants/bacteria-and-other-prokaryotes/management-cyanobacter">http://pnwhandbooks.org/plantdisease/pathogen-articles/pathogens-common-many-plants/bacteria-and-other-prokaryotes/management-cyanobacter</a> Paulitz, T. C. and Schroeder, K. L. 2015. Acid soils- How do they interact with root diseases? WSU Extension Bulletin. Submitted May 14, 2015.  Accepted Aug. 26, 2015. Paulitz, T. C., Schroeder, K. L. and Beard, T. 2015. Sclerotinia stem rot or white mold of canola. WSU Extension Bulletin. Submitted March 2, 2015. Accepted Nov. 2015, Pethybridge, S. J., Abawi, G., Stewart, C., and Stewart, C. 2015. Bloat nematode in garlic. June 2015. Pp. 3. Pethybridge, S. J., MacNeil, C., and Dunn, A. R. 2014. White mold of dry beans.  Disease Factsheet for NY Dry Bean Growers. Pp. 3. Pethybridge, S. J., Maloney, E. C., Kikkert, J. R., and MacNeil, C. 2015. Fungicide-based control of white mold in dry beans in New York State.  17 September 2015.  Pp. 4. Pethybridge, S. J., Smart, C. D., and MacNeil, C. 2015. Disease management in organic dry bean production.  Meeting of the New York Organic Dry Bean Industry, 9 February 2015.  Pp. 2. Pethybridge, S. J., Telenko, D., and Dunn, A. R. 2014. White mold (fresh vegetables).  Disease Factsheet for Fresh Vegetables Growers.  Pp. 3.    Meeting presentations and proceedings   Aujla, I. S. and Paulitz, T. 2015.   How temperature and water potential affect the growth of Fusarium and Rhizoctonia pathogens of wheat.    Transitioning Cereal Systems to Adapt to Climate Change, Minneapolis, MN, Nov. 13-14, 2015. Aujla, I. S. and Paulitz, T. 2015. How temperature and water potential affect the growth of Fusarium and Rhizoctonia pathogens of wheat.    6th Annual Northwest Climate Change Conference. Coeur d’Alene, ID Nov. 3-5, 2015. Bartelt, T., Dunn, A. R., and Pethybridge, S. J. 2015. Relationship between phenotype and genotype among New York Sclerotinia sclerotiorum isolates.  Proc. 2015 Summer Scholars Program, Undergraduate Research Program Session, 31 July, Cornell University, New York Agricultural Experiment Station, Geneva, NY,  Pp. 2. Becker, J. O. 2015. Evaluation of novel nematicides in coastal California turf. 61th Conference on Soilborne Plant Pathogens & 47st Statewide Nematology Workshop, UC Riverside, March 24-26, 2015. Becker, J. O. 2015. Four year Southern California field assessment of new nematicides against root-knot nematodes in processing tomato. 47th Annual Meeting of the Organization of Nematologists of Tropical America (ONTA), Varadero, Cuba, May 18-22, 2015. Becker, J. O. 2015. Mitigation of root knot nematode damage in carrot production by a seed-delivered nematicide. International Plant Pathology Conference, Berlin, Germany, August 24-27, 2015. Becker, J. O. Multistate Research Project meeting, W3147, "Managing Plant Microbe Interactions in Soil to Promote Sustainable Agriculture", Mission Inn, Riverside, CA. Dec 6, 2013. “Evaluation of a strain of Purpureocillium lilacinum”. Benemann, C. and Parke, J. 2015. Relative quantification of soilborne inoculum of Phytophthora ramorum in an Oregon tanoak forest. Western International Forest Disease Working Conference, Newport, OR. Poster presentation. Borneman, J. 2014. Identifying Functionally Important Bacteria By Examining Host-Associated Microorganisms. Invited Presentation. 17th Annual Loma Linda University Basic Science Research Symposium, November 13, 2014. Borneman, J. 2015. Improving the Sugar Beet Cropping Decision Model in the Imperial Valley. Invited Presentation: 61st Conference on Soilborne Plant Pathogens, March 25, 2015. Borneman, J. 2015. Creating Suppressive Soils in Commercial Agricultural Fields. Annual Meeting of Western Regional Project W-3147 on Biological Control, December 4, 2015, Mission Inn, Riverside, CA Daugovish, O., Shennan, C., Muramoto, J., and Mazzola, M. 2015. Carbon source and irrigation affect anaerobic soil disinfestation in strawberry. Pages 12.1-12.3, In, International Conference on Methyl Bromide Alternatives. MBAO, Fresno, CA.  November 8-11, 2015. du Toit, L.J. 2014 Black leg, light leaf spot, and white leaf spot epidemic in the Willamette Valley of Oregon: Protecting Washington’s Brassica seed industry. Puget Sound Seed Growers’ Association Annual Meeting, 30 Jan. 2015, Mount Vernon, WA. (75 people) du Toit, L.J. Allium, bean, and crucifer seed quarantines in Washington: Do the rules suffice? Columbia Basin Crop Consultants’ Association 2015 Short Course, 21-22 Jan. 2015, Moses Lake, WA. (~150 people) du Toit, L.J. Allium, bean, and crucifer seed quarantines in Washington: Do the rules suffice? Columbia Basin Vegetable Seed Association Annual Meeting, 20 Jan. 2014, Moses Lake, WA. (~100 people) du Toit, L.J. Black leg in brassica crops and foliar nutrient analyses for table beet seed crops. Wilbur-Ellis Co. and Sakata America Annual Seed Growers’ Meeting, 3 Feb. 2015, Burlington, WA. (75 people) du Toit, L.J. Black leg of crucifers in the Pacific Northwest: Lessons learned from the 2014 Willamette Valley epidemic. Skagit Farmers’ Supply Growers’ Recertification Day, 18 Feb. 2015, Mount Vernon, WA. (~150 people) du Toit, L.J. Black leg, light leaf spot, and white leaf spot of crucifers in the Pacific Northwest: Lessons learned from the 2014 Willamette Valley epidemic. Douglas Co. and Okanogan Co. Growers Meeting. Invited to help growers avoid introducing seedborne pathogens on crucifer cover crop and canola seed. 3 Mar. 2015, Waterville, WA. (25 people) du Toit, L.J. Emerging Brassica diseases in the Pacific Northwest: Black leg, light leaf spot, and white leaf spot. Presentation to the Emerging Disease Issues Committee, 54th American Seed Trade Association Vegetable & Flower Conference, 24-27 January 2015, Tampa, FL (80 people) du Toit, L.J. Ignorance is bliss? History repeated for brassica black leg in the Pacific Northwest. Presentatoin to Skagit Co. Commissioners, 25 Aug. 2015, Mount Vernon, WA. (5 people + recording of presentation televised publicly: <a href="http://skagit.granicus.com/MediaPlayer.php?view_id=8&clip_id=2036">http://skagit.granicus.com/MediaPlayer.php?view_id=8&clip_id=2036</a>) du Toit, L.J. Ignorance is bliss? History repeated for crucifer black leg in the Pacific Northwest. General Vegetable Session of the Pacific Northwest Vegetable Association Annual Convention & Trade Show, 18-19 Nov. 2015, Kennewick, WA. (~100 people) du Toit, L.J. Ignorance is bliss? History repeated for crucifer black leg in the Pacific Northwest. Washington Tilth Producers’ Association Annual Meeting, 13-15 Nov. 2015, Spokane, WA. (~50 people) du Toit, L.J. Onion diseases in Washington State. Invited presentation at 38th Argentine Horticultural Congress, 16th National Floricultural Conf., 8th Scientific Meeting on Onion from MERCOSUR, and 3rd Regional Plant Protection and Toxicology Conf., 5-8 Oct. 2015, Bahía Blanca, Argentina. (150 attendees). Also participated in meetings with onion stakeholders in Lower Rio Colorado River, Argentina, with a presentation at each on bulb rots. du Toit, L.J. Onion internal dry scale and bulb rots. Onion Session of the Pacific Northwest Vegetable Association Annual Convention & Trade Show, 18-19 Nov. 2015, Kennewick, WA. (~250 people) du Toit, L.J. Table beet seed production in Washington: 2014 Disease and fertility assessments. Puget Sound Seed Growers’ Association Annual Meeting, 30 Jan. 2015, Mount Vernon, WA. (75 people) du Toit, L.J., and Derie, M.L. Suppression of Fusarium wilt in spinach seed production using compost. 2015 International Spinach Conference, 24-25 Feb. 2015, Yuma, AZ (also listed in abstracts above). (~200 people) Funahashi, F. and Parke, J. 2015. Development of a predictive model to estimate conditions lethal to soilborne inoculum of Phytophthora ramorum and Phytophthora pini during soil solarization. APS Annual Meeting, Pasadena, CA. Oral presentation. Phytopathology 105(S4):46 Funahashi, F., Myrold, D. D., and Parke, J. 2015. Effect of soil solarization and Trichoderma biocontrol application on soil fungal and prokaryotic communities investigated with next generation sequencing. Soil Science Society of America Annual Meeting, Minneapolis, MN. Oral presentation. Jiang, H., and J. Hao. 2015. Compounds from zoospore exudate serve as a signal to promote zoosporic germination and infection of Phytophthora erythroseptica. Phytobiomes 2015, Washington, DC held from Jun. 30 to Jul. 2. Lien, A., Gorny, A., and Pethybridge, S. J. 2015. Development of species-specific PCR primers and assessment of DNA extraction techniques for the detection of Meloidogyne hapla in soil.  Proc. 2015 Summer Scholars Program, Undergraduate Research Program Session, 31 July, Cornell University, New York Agricultural Experiment Station, Geneva, NY,  Pp. 2. Mazzola, M. and Hewavitharana, S. S. 2015. ASD efficacy is associated with altered soil microbiome and metabolome. Pages 13.1-13.4, In, International Conference on Methyl Bromide Alternatives. MBAO, Fresno, CA.  November 8-11, 2015. Mazzola, M., and Wang, L. 2015. Reduced rate seed meal amendment efficacy is plant genotype-dependent. Pages 14.1-14.4, In, International Conference on Methyl Bromide Alternatives. MBAO, Fresno, CA.  November 8-11, 2015. Mazzola, M., Hewavitharana, S. S., Strauss, S. L., Shennan, C., and Muramoto, J. 2015. Effect of anaerobic soil disinfestation and Brassica seed meal amendment on soil biology and system resistance. 8th North American Strawberry Symposium, Feb. 3-6, 2015, Ventura, CA. Meng, Q., Jiang, H., and Hao, J. 2015. Characterization of Bacillus amyloliquefaciens strain BAC03 for plant growth promotion. APS Annual Meeting, Pasadena, CA. Aug. 1 to 4. Mitchell, P. D., Dong, F., Wille, N., Knuteson, D., Bussan, A. J., Colquhoun, J., Dillard, D., Gevens, A., Groves, R., Kikkert, J., Nault, B., Pethybridge, S., Ruark, M., and Wyman, J. 2015. Conceptual framework and empirical results for a practical agricultural sustainability program in the United States. Int. Conf. Food in the Bio-based Economy, Wageningen, The Netherlands, 27-29 May 2015. Muramoto, J., Shennan, C., Zavatta, M., Baird, G., Toyama, L., and Mazzola, M. 2015. Effect of anaerobic soil disinfestation and mustard seed meal for control of charcoal rot in California strawberries. 8th North American Strawberry Symposium, Feb. 3-6, 2015, Ventura, CA. Muramoto, J., Shennan, C., Zavatta, M., Toyama, L., Hewavitharana, S. S.., and Mazzola, M. 2015. Conrolling Fusarium wilt of strawberries by anaerobic soil disinfestation. Pages 16.1-16.4, In, International Conference on Methyl Bromide Alternatives. MBAO, Fresno, CA.  November 8-11, 2015. Myers, R., and du Toit, L.J. Keynote panel – An overview of cover cropping in the PNW – Opportunities and challenges. Presentation on the 2014 black leg epidemic in the Willamette Valley, and potential modifications to the WSDA crucifer quarantine to protect brassica oilseed crops in the irrigated and dryland areas of central and eastern Washington. 2015 PNW Oilseed & Direct Seed Conference, 20-22 Jan. 2014, Kennewick, WA. (~250 people) <a href="http://css.wsu.edu/biofuels/presentations/2015pnw-oilseed-direct-seed-conference/powerpoint-presentations/">http://css.wsu.edu/biofuels/presentations/2015pnw-oilseed-direct-seed-conference/powerpoint-presentations/</a> Okubara P, Paulitz T, Yin C, Mahoney A, Mueth N, Hulbert H, 2015, Bacterial community profiling in Rhizoctonia soils. Plant and Animal Genome XXIII, January 10-14, 2015, San Diego, CA, P0461, p. 240. (Poster) Okubara, P. 2015. Cultivar-Specific Rhizosphere Traits in Wheat Root. 9th International Symposium of the International Society of Root Research entitled Roots down under - Belowground solutions to global challenges, Canberra, Australia, October 5-9, 2015. (Invited talk) Paulitz, T. 2015 Long-term agricultural research: A means to achieve resilient agricultural production for the 21st Century and beyond. A symposium at the 70th Annual Soil and Water Conservation Society, Greensboro, NC July 26-29, 2015. Presented invited talk- “Long Term Agriculture Research: Disease Management”. Paulitz, T. 2015. Canola Diseases. Washington State Biofuels Cropping Systems Meeting, Pullman, Washington February 26, 2015 Paulitz, T. 2015. Crop rotation and soilborne pathogens. Lecture in Advanced Cropping Systems. Department of Crop and Soil Sciences, Washington State University. Oct.20, 2015 Paulitz, T. 2015. Interactions of Soil pH and Soilborne Pathogens of Wheat. Lecture in Soil Plant Microbial Interactions. Department of Crop and Soil Sciences, Washington State University. Dec 10, 2015 Paulitz, T. 2015. Long-term agricultural research: A means to achieve resilient agricultural production for the 21st Century and beyond. Presented invited talk symposium “Long Term Agriculture Research:  Disease Management” at the Tri- Society Meeting, Minneapolis, MN November 15-18, 2015.  Paulitz, T. 2015. Managing Plant-Microbe Interactions in Soil to Promote Sustainable Agriculture- Washington Update,W-3147 Multistate Group Dec. 4, 2015. Riverside, CA Paulitz, T. 2015. Natural suppression of Rhizoctonia bare patch of wheat in no-till: The role of microbial communities. Department of Plant Pathology, Washington State University. Feb 2, 2015. Seminar. Paulitz, T. 2015. Nematode Diseases. Lecture and Lab for Introductory Plant Pathology. Department of Plant Pathology, Washington State University. Nov. 4, 2015 Paulitz, T. 2015. Soil health and plant health: the pathogen connection. Keynote talk at “Soil Health and Management for Ag Professionals” Worland Community Center, Worland, WY May 26-27, 2015 Paulitz, T. C. 2015. From Cal Poly to Pullman- Recollections of a Plant Pathologist.  A talk given to students and faculty of the School of Agriculture, California Polytechnic University, Pomona, Dec. 8, 2015. Paulitz, T. C. 2015. Canola Diseases- Rhizoctonia and Blackleg. Pacific Northwest Direct Seed Meeting, Kennewick, Washington, January 19-22, 2015 Paulitz, T. What’s new in root disease research. Spokane Farm Forum, Ag Expo, Spokane, Washington, February 4, 2015 Peterson, E., Parke, J., and Grunwald, N. 2015. Incubation in soil reduces sporulation and risk of epidemic development from leaf disks infested by Phytophthora ramorum. APS Annual Meeting, Pasadena, CA. Oral presentation. 105(S4):110. Smith Becker, J. and J.O. Becker 2015. Growth kinetics of Dactylella oviparasitica strains in a peat carrier. 47th Annual Meeting of the Organization of Nematologists of Tropical America (ONTA), Varadero, Cuba, May 18-22, 2015. Smith Becker, J., and J.O. Becker 2015. Comparative virulence of Dactylella oviparasitica strains for the control of Heterodera schachtii. International Plant Pathology Conference, Berlin, Germany, August 24-27.   Abstracts   Aujla, I. S. and Paulitz, T. C. 2015. Effect of temperature and water potential on the hyphal growth rate of Fusarium and Rhizoctonia pathogens of wheat. Phytopathology 105(Suppl. 4):S4.9 Becker, J.O. 2015. What’s New With Nematicides? Proceedings Desert Horticulture Conference, Tucson, p.6. Becker, J.O., A. Ploeg, and J. Nunez 2015. Control of root-knot nematodes in fresh carrot production in California. Abstract Booklet International Carrot Conference, Ontario, Canada, 2015. Becker, J.O., A. Ploeg, and J. Nunez 2015. Four year Southern California field assessment of new nematicides against root-knot nematodes in processing tomato. Abstract book 47th Annual Meeting of the Organization of Nematologists of Tropical America (ONTA), Varadero, Cuba, May 18-22, 2015. p. 43. Becker, J.O., and H.V. Morton 2014. Seed treatments against plant parasitic nematodes: When a little goes a long way. Proceedings of 6th International Congress of Nematology, Cape Town, SA, p. 90. Chen, W., McGee, R., Paulitz, T., Porter, L., Vandemark, G., Guy, S., and Schroeder, K. 2015. Collins, B.D., McDonald, M.R., du Toit, L.J., and Westerveld, S. 2015. Evaluation of management practices for Fusarium wilt in bunching spinach production in Ontario, Canada. 2015 International Spinach Conference, 24-25 Feb. 2015, Yuma, AZ.    Department of Crop and Soil Sciences Technical Report 15-1 du Toit, L.J., Derie, M.L., Youngquist, C.P., and Holmes, B.J. Suppression of Fusarium wilt in spinach seed production using compost. 2015 International Spinach Conference, 24-25 Feb. 2015, Yuma, AZ. Hao, J. 2015. Soil microbial communities: the cause and solutions of plant diseases. XVIII International Oil Palm Conference. Hao, J. J., H. H. Jiang, X. Y. Zhang, X. Zhang, and N. Marangoni. 2015. Effects of chemical and non-chemical products on pink rot of potato. The 1st Soilborne Oomycete International Conference. Hao, J., H. Jiang and S. B. Johnson. 2016. Detection and characterization of Dickeya species in the outbreak of blackleg disease of potato in Maine. Northeastern Division of The American Phytopathology Anuual Meeting. Hewavitharana, S. S., Shennan, C., Muramoto, J., and Mazzola, M. 2015. Anaerobic soil disinfestation disease control performance in strawberry influenced by environmental variables. Phytopathology 105:S4.59. 2015 Annual Meeting of American Phytopathological Society, Pasadena, CA. Jiang, H. and J. Hao. Compounds from zoospore exudate serve as a signal to promote zoosporic germination and infection of Phytophthora erythroseptica. Phytobiomes 2015, Washington, DC. Jiang, H., Meng, Q., and Hao, J. 2015. Optimization of Bacillus amyloliquefaciens BAC03 application in controlling Streptomyces scabies. APS annual meeting. Kaur, G., Lujan, P., Sanogo, S., and Puppala, N. 2015. Efficacy of fungicides on mycelial growth and pigmentation, and sclerotia and oxalic acid production by Sclerotinia sclerotiorum. (Abstract, Annual Meeting of APS, Pasadena, CA, August 1-5, 2015). Lujan, P., Sanogo, S., and Puppala, N. 2015. Evaluating peanut varieties for resistance to Sclerotinia sclerotiorum. (Abstract, Annual Meeting of APS, Pasadena, CA, August 1-5, 2015). Manning-Thompson, Y., Smiley, R., Paulitz, T. and Garland-Campbell, K. 2015. Screening for resistance to cereal cyst nematode in locally adapted spring wheat cultivars of the Pacific Northwest. 2015 Field Day Abstracts, Dept. of Crop and Soil Sciences, Technical Report 15-1. Pg. 54. McFarland, C., Kahl, K., Huggins, D., Carpenter-Boggs, L., Koenig, R., Blackburn, J., Schroeder, K. and Paulitz, T. 2015.  How much lime to apply?  2015 Field Day Abstracts, Dept. of Crop and Soil Sciences, Technical Report 15-1. Pg. 23. McFarland, C., Kahl, K., Huggins, D., Carpenter-Boggs, L., Koenig, R., Blackburn, J., Schroeder, K. and Paulitz, T. 2015.  How surface-applied lime products affect soil fertility.  2015 Field Day Abstracts, Dept. of Crop and Soil Sciences, Technical Report 15-1. Pg. 24. McLeod, A., and Mazzola, M. 2015. Towards integrated management of apple replant disease using knowledge of disease etiology. Pages 73-75, In, Proceedings Integrated Plant Protection in Fruit Crops, Stellenbosch, South Africa, November 24-28, 2014. Meng, Q., Jiang, H., and Hao, J. 2015. Characterization of Bacillus amyloliquefaciens strain BAC03 for plant growth promotion. APS annual meeting. Metalaxyl resistance and Pythium damping-off of chickpea . 2015 Field Day Abstracts, Dept. of Crop and Soil Sciences, Technical Report 15-1. Pg. 41. Miyao, G., B. Leacox, A. Harlan, A. Ploeg, J.O. Becker, R.M. Davis 2014. Alternative practices for the management of nematode and soilborne fungal diseases in California processing tomatoes in the Lower Sacramento Valley. 29th Annual Tomato Disease Workshop, Windsor, Canada, p. 21. Nyoni, M., Mazzola, M., and McLeod, A. 2015. Evaluating systemic semi-selective chemicals for the management of apple replant disease in fumigated and non-fumigated orchard systems. International Plant Protection Congress. August 24-27, 2015, Berlin, Germany. Paulitz, T., Sharma-Poudyal, D., Yin, C. and Hulbert, S. 2015. Effect of long-term no-ill on soil fungal communities in dryland wheat cropping systems. 2015 Field Day Abstracts, Dept. of Crop and Soil Sciences, Technical Report 15-1. Pg. 51. Ploeg, A., J.O. Becker, and J. Nunez 2015. Field and micro-plot trials on use of mustard-type crops to manage root-knot nematodes in carrot and tomato in California. Abstract book 47th Annual Meeting of the Organization of Nematologists of Tropical America (ONTA), Varadero, Cuba, May 18-22, 2015. p. 64. Reed, A. J., and Mazzola, M. 2015. Characterization of apple replant disease-associated microbial communities over multiple growth periods using next-generation sequencing. Phytopathology 105:S4.117. 2015 Annual Meeting of American Phytopathological Society, Pasadena, CA. Sánches-Portillo, J.F., G.A. Lugo-Garcia, M. Mundo-Ocampo, I. De Ley-Tandingan, and O. Becker 20014. Aislamiento, caracterizatión y virulencia de hongos nematófagos contra Meloidogyne spp. XVI International Congress and XLI Mexican Phytopathological Society Congress, Ixtapan de la Sal, Estado de México, México. Sánches-Portillo, J.F., G.A. Lugo-Garcia, M. Mundo-Ocampo, I. De Ley-Tandingan, and J. O. Becker 20014. Isolation of nematophagous fungi against Meloidogyne spp. in the north of Sinaloa, Mexico. Abstract book 47th Annual Meeting of the Organization of Nematologists of Tropical America (ONTA), Varadero, Cuba, May 18-22, 2015. p. 105. Sanogo, S, Lujan, P., Rudolph, R., Uchanski, M., and Walker, S. 2015. Integration of spring-planted mustard cover crop and mustard seed meal for control of Verticillium wilt in chile pepper. (Abstract, Annual Meeting of APS, Pasadena, CA, August 1-5, 2015). Sanogo, S., Lujan, P., and Idowu, J. 2015. Reduction in the population of Phytophthora capsici and disease severity in chile pepper by extracts from pecan shell and husk tissues (Abstract, Annual Meeting of American Phytopathological Society (APS), Pasadena, CA, August 1-5, 2015). Shennan, C., Muramoto, J., and Mazzola, M. 2015. Anaerobic Soil Disinfestation (ASD): a strategy for control of soil borne diseases in strawberry production. ISHS International Symposium Innohort 2015, June 8-12, 2015, Vignon, France. Page 25 in book of abstracts Simon, P., Colley, M., McKenzie, L., Zystro, J., Hoagland, L., Roberts, P., Colquhoun, J., du Toit, L., Nunez, J., Silva, E., and Waters, T. 2015. Cultivar development with the CIOA (Carrot Improvement for Organic Agriculture) project targets flavor, novel colors, top height, and disease and pest resistance. 37th Internat. Carrot Conf., 15-17 Sep. 2015, Nottawasaga Inn Resort & Conf. Centre, Alliston, Ontario, Canada. Smith Becker, J. and J.O. Becker 2015. Growth kinetics of Dactylella oviparasitica strains in a peat carrier. Abstract book 47th Annual Meeting of the Organization of Nematologists of Tropical America (ONTA), Varadero, Cuba, May 18-22, 2015. pp. 105-106. Smith Becker, J., and J.O. Becker 2015. Comparative virulence of Dactylella oviparasitica strains for the control of Heterodera schachtii. 18th International Plant Protection Congress 2015, Berlin. Abstract Booklet p. 249. Smith Becker, J., H. Witte, and J.O. Becker 2014. Peat as a suitable growth media and carrier for Dactylella oviparasitica. Proceedings of 6th International Congress of Nematology, Cape Town, SA, p. 240. Sowers, K., Paulitz, T., Davis, J., Du Toit, L., Schroeder, K. and Wysocki, D. 2015. Blackleg in canola – Reason for alarm in Washington State? 2015 Field Day Abstracts, Dept. of Crop and Soil Sciences, Technical Report 15-1. Pg. 31. Wang, L., and Mazzola, M. 2015. Integration of apple rootstock genotype with reduced Brassica seed meal application rates for replant disease control. Phytopathology 105:S4.145. 2015 Annual Meeting of American Phytopathological Society, Pasadena, CA. Yin, C., Schoreder, K., Mueth, N. and Hulbert, S. 2015. Bacterial communities on wheat grown under long-term conventional tillage and no-till in the Pacific Northwest of the US.   Phytopathology 105(Suppl. 4):S4.154 Zhang, X. M., H. Jiang, J. Hao, and S. B. Johnson. 2016. Effects of Chemical and Biological Products on Pink Rot of Potato. Northeastern Division of The American Phytopathology Anuual Meeting. Zhu, Y., Mazzola, M., and Fazio, G. 2015. Differential transcriptional regulation of defense-associated genes among apple rootstock genotypes in response to Pythium ultimum. Phytopathology 105:S4.159. 2015 Annual Meeting of American Phytopathological Society, Pasadena, CA.   Extension Talks/Field Days/Workshops/Consultations   Becker, J. O.   2015. Crop protection against plant parasitic nematodes: novel approaches and agents. CAPCA Progressive Farmers Meeting, Blythe, CA, March 19, 2015. Becker, J. O.   2015. From suppressive soils to biological control of Heterodera schachtii. 26th Annual Fall Desert Crops Workshop; El Centro, CA, Oct 29, 2015. Becker, J. O.   2015. Turf Management: Nematodes in California Turf. University Extension Turf Management Certificate Course, 3-hr Webinar, UC Riverside Extension, Oct 20, 2015 Becker, J. O.   2015. Updates and control practices for nematodes of importance to Ventura Co., CAPCA Ventura, Santa Paula, September 9, 2015. Becker, J. O.   2015. What’s New With Nematicides? Desert Horticulture Conference, Tucson, June 5, 2015. Becker, J. O. 2015. The Sting Nematode, a Subterranean Invasive Species in the Coachella Valley. First annual “Do No Harm” workshop, UC Riverside Palm Desert Center, November 5, 2015 Becker, J. O. 2014. Next-Generation Nematicides. 25th Annual Fall Desert Crops Workshop 2014. El Centro, CA, November 13, 2014. Becker, J. O. 2015. Anguina pacificae, a galling problem in some coastal golf courses in Northern California. Nem250 Department Seminar, UC Riverside, CA, Feb 11, 2015. Becker, J. O. 2015. Impact of novel nematicides on carrot health in root-knot nematode-infested fields. Annual California Fresh Carrot Advisory Board Research Symposium, Bakersfield, CA, March 10, 2015. Becker, J. O., A. Ploeg, J. Nunez 2015. Evaluation of new nematicides against root-knot nematodes in processing tomato production. Annual California Processing Tomato Research Meeting, Davis, CA, Dec 4, 2014. Becker, J. O.2015. Fluensulfone evaluation in CA fresh market carrots. Nematode Management in Western Vegetable Production Workshop, Riverside, CA, Dec 16, 2014. Doane, S. and Parke, J. Dec. 10, 2015. Soil solarization of tree seedling production beds to reduce weeds and soilborne pathogens. Shade Tree Growers Meeting, Aurora, OR. du Toit, L.J. and Benedict, C. Brassica clubroot needs assessment. 9 Mar. 2015, Everson, WA. Met with growers from smaller-scale, diversified farms in Whatcom Co. to discuss clubroot impact, management practices, and research needs; and to initiate planning for a Farmer-Researcher SARE grant application. du Toit, L.J. and Derie, M.L. 6th Annual Spinach Fusarium Wilt Soil Bioassay, 19 Feb. 2015. Open house for spinach seed growers and seed companies to observe how spinach parent lines ranging from highly susceptible to partially resistant fare in a bioassay to test soil sampled from growers’ fields for relative risk of Fusarium wilt. Soil samples (5 gal/field) were submitted from 29 fields in Dec. 2014 for the bioassay ($200/field). Growers and seed company reps viewed results to decide which fields to select for planting spinach seed crops in 2015. This was the 6th winter the bioassay has been offered, with >200 fields in northwestern WA tested since 2010 to quantify spinach Fusarium wilt risk. du Toit, L.J. and Waters, T. Vegetable Crops Management 101. Co-organized with Pacific Northwest Vegetable Extension Group. 4-hour workshop requested by Pacific Northwest Vegetable Association (PNVA) Board of Advisors to provide training on vegetable diagnosis, insect/pest management, weed management, fertility, and irrigation (8 speakers). Presentations translated into Spanish. Spanish and English handouts/presentations provided. (68 people) du Toit, L.J. Diagnosing Diseases in the Field. Presented a 45-minute webinar for Oregon State University Integrated Pest Management Workshop series coordinated by S. Rondon and S. Reitz, and funded by Western Sustainable Agriculture Research & Education. <a href="https://media.oregonstate.edu/media/t/0_7kh2o95w">https://media.oregonstate.edu/media/t/0_7kh2o95w</a> du Toit, L.J. Organic Seed Alliance Research Field Day, 14 Oct. 2015, Chimacum, WA. Discussion on black leg of crucifers, risk management, and pending WSDA quarantine regulation. (25 people) du Toit, L.J. Organized a hands-on lab/greenhouse workshop on diagnosis, pathogenicity testing, and other aspects of the brassica black leg pathogen, Phoma lingam, for Jim Davis and Megan Wingerson, University of Idaho, in response to a widespread outbreak of black in canola crops in west-central Idaho in spring 2015. 15 Jul. 2015, Mount Vernon, WA. du Toit, L.J. WSU Extension Onion Field Day, 27 Aug. 2015, Grigg & Sons farm, Quincy, WA. Presented onion disease information and research updates on bulb rots, internal dry scale, and mycorrhizae to growers, seed industry, extension personnel, researchers, etc. (100 people). Hao, J. 2015. “Towards better solutions in managing soilborne diseases of potato.” China Agricultural University. Beijing, June 23, 2015. Hao, J. 2015. “Towards better solutions in managing soilborne diseases of potato.” China Agricultural University. Baoding, Hebei, June 19, 2015. Hao, J. 2015. “Potato Pink Rot and Management.” 30th Annual Maine Potato Conference. Caribou Inn, ME. Jan. 21 to 22. 200 attendees. Hao, J. 2015. “Soil Fumigation in Controlling Soilborne Diseases in Maine.” The 1st Chloropicrin Summit Meeting. The Carolina Hotel, Pinehurst. NC. Nov. 2 to 4, 2015. Hao, J. 2015. “Soil microbial communities: the cause and solutions of plant diseases.” XVIII International Oil Palm Conference.” Hotel La Americanas, Cartagena, Colombia. September 22 to 25, 2015. Hao, J. 2015. “Effects of chemical and non-chemical products on pink rot of potato.” The 1st Soilborne Oomycete International Conference, Duck Key, FL.  Dec. 8-10, 2015. Hao, J. 2015. “Microbial activities and disease management in potato.” China Agricultural University. Kunming, Yunnan, June 15, 2015. Hao, J. 2015. “Small grain leaf and seed diseases and management strategies.” Maine Grain Conference. Bangor, ME, Mar 13. Hao, J. 2015. Isolation, detection and characterization of pathogenic bacteria causing black leg of potato in Maine.” National Potato Council Seed Potato Certification Sub-Committee Meeting, Washington DC, VA. Dec. 2-4, 2015. Mazzola, M. ASD, Mustard Seed Meal and Wheat Cover Crops for Soil-borne Disease Control: Potential Mechanisms of Action. California Department of Pesticide Regulation Update on Soil Fumigation. December 12, 2014, Watsonville, CA. Mazzola, M. Field days on application of anaerobic soil disinfestation, mustard seed meal amendment and low rate fumigation treatment for control of Fusarium wilt. California Strawberry Commission, August 11, 2015, Watsonville, CA. Mazzola, M. Managing Soil Microbiology for Replant Disease Control and System Resilience, Meeting of the Greenbluff Growers Horticultural Association, April 1, 2015, Green Bluff, WA. Mazzola, M. Role of Soil Microbiology in Orchard System Function & Productivity. Washington State University “Fruit School”. November 17, 2015. Nunez, J., J.O. Becker 2014. Moving forward in nematode management while avoiding past mistakes. Processing tomato field. Shafter, CA, Oct 14, 2014. Parke, J. L. April 28, 2015. Webinar. A systems approach to producing healthy container-grown plants. (Target audience: growers of native plants for restoration projects.)110 participants. <a href="https://uc-d.adobeconnect.com/_a841422360/p4o2997j55g/?launcher=false&fcsContent=true&pbMode=normal">https://ucd.adobeconnect.com/_a841422360/p4o2997j55g/?launcher=false&fcsContent=true&pbMode=normal</a> Paulitz, T. 2015. Update on Blackleg. Lind Dryland Research and Extension Center Field Day, June 11, 2015 Paulitz, T. 2015. Management of nematode diseases with genetics. Washington Grain Commission Review, Pullman, WA, Feb 28, 2015 Paulitz, T. C. Update on Blackleg of Canola. Far West Agribusiness Winter Conference, Kennewick, WA Dec. 9, 2015

Impact Statements

We obtained data for adding the population levels of the fungus Dactylella oviparasitica to cropping decision models, which we anticipate will lead to higher crop yields and profitability for the growers.

Date of Annual Report: 02/16/2017

Report Information

Annual Meeting Dates: 12/02/2016 - 12/02/2016
Period the Report Covers: 10/01/2015 - 09/30/2016

Participants

Becker, Ole (obecker@ucr.edu) - University of California, Riverside
Borneman, James (borneman@ucr.edu) - University of California, Riverside
Gachomo, Emma - (emma.gachomo@ucr.edu) - University of California, Riverside
Hao, Jianjun (jianjun.hao1@main.edu) - University of Maine
Lavine, Laura (lavine@wsu.edu) - Washington State University
Paulitz, Tim (paulitz@wsu.edu) - USDA-ARS-WA
Ploeg, Antoon (antoon.ploeg@ucr.edu) - Univ. of California, Riverside
Yuen, Gary (gyuen1@unl.edu) - University of Nebraska

Brief Summary of Minutes

Minutes

2016 Meeting of the Multistate Project W3147

December 2, 2016

Mission Inn,

Riverside, CA

James Borneman, Chair & local arrangements

Antoon Ploeg, Secretary

Members in attendance:

Ole Becker (CA), James Borneman (CA), Emma Gachomo (CA), Jianjun Hao (ME), Laura Lavine (WA), Tim Paulitz (WA), Antoon Ploeg (CA), Gary Yuen (NE).

The meeting started at 8:30 AM with the chair’s welcome and self-introduction of attendees.

The minutes from the 2015 meeting were approved.

Antoon Ploeg volunteered to be the secretary for this meeting.

Laura Lavine provided information on the reporting requirements and web-based resources on how to write impact statements.

It was noted that our project is in year 3, and that a new proposal is probably due around February 2018.

December 1, 2017 was selected as the data for the next meeting. Location: Mission Inn, Riverside, CA. Possibility to participate through skype/zoom will be investigated from those who cannot attend the meeting in person.

Progress reports:

Jianjun Hao reported on Oomycete diseases, particularly pink-rot, in potato.

Ole Becker reported on nematode issues in CA carrot production.

Antoon Ploeg reported on root-knot nematode studies in sweetpotato and tomato.

Gary Yuen reported on biocontrol potential of Fusarium diseases in Nebraska

Tim Paulitz presented progress of several studies particularly those related to Rhizoctonia disease in Washington state.

James Borneman provided information on the APS journal “Phytobiomes” and reported on studies related to soil suppressiveness of sugarbeet cyst nematodes. Before adjourning the meeting, the members thanked James Borneman for an outstanding job in handling the local arrangements.

Submitted: Antoon Ploeg.

Accomplishments

Objective 1 To identify and characterize new biological agents, naturally suppressive soils, cultural practices, and organic amendments that provide management of diseases caused by soilborne plant pathogens. CA- One of the long-term goals of my research programs is to develop more sustainable strategies to manage soil-borne plant pathogens.  To accomplish this, we are endeavoring to understand soils that naturally inhibit plant pests and disease, termed suppressive soils. Key steps in realizing the potential of these soils are to identify the causal organisms and then understand the agronomic and environmental factors that enable them to function.  Armed with such knowledge, it should be possible to develop effective and sustainable pest management strategies through the application of the organisms and through agronomic practices that influence their populations.  To date, we have identified several fungi involved in suppressing sugarbeet cysts nematodes (Dactylella oviparasitica and Fusarium oxysporum) and root-knot nematodes (Pochonia chlamydosporium and a Tetracladium sp.).  We have also identified new Dactylella oviparasitica phylotypes, which suggests that these fungi may represent a large group of potentially effective biological control agents, and which can be found worldwide.  In addition, we have determined that soils with no detectable Dactylella populations can harbor this fungus, and which can dramatically increase during one host cropping cycle.  This is a key finding, suggesting that standard methods for screen soils for putatively protective microorganisms will not work.  We have also presented a new approach and supporting data for using Dactylella population densities in planting decisions models. CA-Another long-term goal is to develop new methods that enable a greater understanding of the roles microorganisms play in processes such as nematode and replant disease.  In prior research, we developed several molecular and computational methods that should facilitate a greater understanding of these phenomena.  We are continuing these efforts by developing a high-throughput method for microbial community analyses, a software package for designing PCR primers and probes, and a statistical method for classifying soils (or other entities). CA- Dactylella oviparasitica (syn. Brachyphoris oviparasitica) is the primary causal agent of a long-term Heterodera schachtii population suppression at a research field site at the University of California Riverside Agricultural Operations. A survey of 80 sugar beet fields in the Imperial Valley, CA, detected the fungus in two-thirds of the samples. We have shown in a greenhouse test that samples with a high detection level of D. oviparasitica exhibited H. schachtii population suppression while samples with no or low signal level were conducive to high nematode reproduction. MS- Over the past year we have shown that benign microbes isolated from rice rhizosphere increase plant fitness and protection against pathogenic fungus.  In addition, we also showed that supplementation by benign microbes induce resistance in plants against abiotic stress such as Arsenic toxicity. Our efforts also showed how plats respond to mixed stress regime when supplemented with benign microbes. In addition, our work also led to characterization of a classical PGPR Bacillus subtilis UD1022 for chemotaxis in plants under aerial pathogen response NE- Field experiments were conducted in 3 Nebraska locations to evaluate the effectiveness of commercial soybean seed treatments with biological agents, for control of Heterodera glycines, the soybean cyst nematode (SCN). The seed treatments included strains of the bacterial species Bacillus firmus and Pasteuria nishizawae combined with commercial fungicides and insecticides, and these were compared with standard seed treatment chemicals alone. Neither of the biological agents decreased SCN reproduction or increased soybean seed yield in comparison to commercial seed treatments with chemicals alone. The results indicate that, under Nebraska conditions, the biological products provide no additional benefits as to of SCN control or yield beyond those already conferred by SCN-resistant soybean varieties and standard chemical seed treatments. This information is important to Nebraska soybean growers in deciding pre-plant management procedures. The bacterial strains tested in these experiments represent the latest commercially-available biocontrol agents for nematode control; the lack of SCN control shown in these experiments point to the need for greater search for and development of new and more effective biological control agents. NE- Nebraska isolates in the bacterial species Burkholderia ambifara were found to be aggressive antagonists against Fusarium spp. in plate inhibition tests, and were effective in greenhouse pot tests in reducing the severity of Fusarium root rot in corn, wheat and soybean compared the no-bacteria control. The bacterial strains were particularly effective when applied to corn, providing over 85% reduction in root rot severity. Differences were found in greenhouse experiments among strains of bacilli (bacteria classified in Bacillus and related genera) as to the ability to stimulate corn growth in the absence of plant pathogens; no connection was apparent between the ability to promote growth and any particular physiological trait (i.e., phosphate solubilization; production of biosurfactants, siderophores, proteases, and auxins). Identification of new bacterial strains with the ability to suppress root rot or the ability to promote plant growth enhance provides new organisms for further study and development toward the creation of commercially effective biocontrol products. Burkholderia ambifara, effective in root rot biocontrol, and some species of the plant growth promoting bacilli (Bacillus safensis, Paenibacillus graminis, and Paenibacillus cineris) have not been reported previously to have these attributes. Their discovery broadens the diversity of organisms from which effective biocontrol products might be developed. NJ- In this period of funding we progressed in three areas related to our project as follows: 1) identification of bacterial endophytes (Pseudomonas spp.) that may be applied to grasses (tested on tall fescue, Kentucky bluegrass, perennial ryegrass, and annual bluegrass) to promote growth of the grass crops and suppress soil borne fungi and seedlings of broadleaf weeds (patent application made); 2) identification of antifungal lipopeptides in Bacillus endophytes and evaluation of their effects on disease incidence in grasses (article currently being drafted); 3) elucidation of a mechanism (‘the rhizophagy cycle’) for endophyte-enhanced nutrient acquisition by grasses through cyclic movement of microbes from rhizosphere to the internal (intracellular) colonization of plant roots and their oxidative degradation (rhizophagy) within internal tissues of roots.  We also made progress in evaluating application of microbes to cultivate cotton. This is particularly important in cotton because cotton seeds are routinely treated with acid to remove fibers.  This treatment leaves seeds free of its defensive microbiome. This research is focused on restoring the defensive microbiome to cotton seeds. Products of this research include a patent (U.S. patent pending no. PCT/US16/43408. (Rutgers University Filed July 21, 2016). “Compositions and Methods Comprising Endophytic Bacterium for Application to Grasses to Increase Plant Growth, Suppress Soil Borne Fungal Diseases, and Reduce Vigor of Weedy Competitors”; Inventors: White JF, Kowalski K, Kingsley K.). Several of our bacterial endophyte strains were licensed by the agricultural company Indigo Agriculture for further testing and potential application in grasses NM- A field study was conducted on a chile producer's farm near Las Cruces, NM, to compare the efficacy of mycorrhizal chile seed treatment and in-furrow application of fungicides for control of Phytophthora blight. The experiment was conducted on a commercial chile farm at Biad Chili Co. Seeds of chile (cultivar Queen B) were planted on March 29, 2016 under four treatments: 1) Grower standard; seeds not treated, but planted with in-furrow application of fungicides (Quadris and Ridomil) and an insecticide (Platinum); 2) seeds not treated, but planted with in-furrow application of fungicides (Quadris and Ridomil), insecticide (Platinum), and mycorrhizal product EndoMaxx (3.7 g/acre) which contains four species of Glomus; 3) seeds treated with EndoMaxx (4 g/acre), and planted with in-furrow application of fungicides (Quadris and Ridomil), and insecticide (Platinum); and 4) seeds treated with EndoMaxx (4 g/acre), and planted with in-furrow application of fungicides (Quadris and Ridomil), an insecticide (Platinum), and EndoMaxx (4.5 g/acre). Stand count was similar across all treatments. With regard to wilt disease incidence, three sections were clearly visible within the field. Disease incidence was consistently low in the section on light texture-soil as opposed to sections on medium and heavy texture-soils. However, there was no statistically significant difference among treatment within each section based on the area under disease control. Results suggest that seed treatment alone with mycorrhizae or fungicides or mycorrhizae in combination with fungicides is not adequate to provide season-long reduction of Phytophthora blight. NY- Change in a Phytophthora capsici population over time. To identify control strategies, it is important to know how a pathogen population in a field is changing over time.  Sexual, endemic populations of the heterothallic Phytophthora capsici continue to devastate vegetable crops in the northeast. In many instances, flooding events introduced P. capsici into fields with no prior history of the pathogen. Common occurrence of both A1 and A2 mating types results in production of oospores, and consequently persistent, overwintering populations. Further, prior research in our lab provides evidence for localized populations, with little to no gene flow between fields in the northeast. To understand the dynamics of these isolated, sexual populations of P. capsici, a restricted access research farm in Geneva, NY, with no prior history of P. capsici, was inoculated in 2008 with two isolates of opposite mating type. Preliminary results from those isolates was reported on last year, and since then a major finding is that the founding F1 oospores were recovered for three years following initial inoculation, but not since that time.  We are currently analyzing data from recent collections to determine how the pathogen evolves over time. Once a field is infested with both mating types of P. capsici, it is currently unfeasible to eradicate the pathogen. Thus, it is essential to understand both the founding and long-term trajectories of P. capsici populations to improve management strategies. NY- Further exploring the population structure of Sclerotinia sclerotiorum in temperate production areas, such as New York. Sclerotinia sclerotiorum populations from tropical agricultural zones have been suggested to be more variable compared to those from temperate zones. However, no data are available comparing populations from both zones using the same set of markers. In this study, we compared S. sclerotiorum populations from the United States of America (USA, temperate) and southeast Brazil (tropical) using the frequency of mycelial compatibility groups (MCGs) and 13 microsatellite (SSR) markers. Populations were sourced from diseased plants within leguminous crops in New York, USA (NY; n = 78 isolates), and Minas Gerais State, Brazil (MG; n = 109). Twenty MCGs were identified in NY and 14 were previously reported in MG. Different alleles segregated in the populations but both had similar levels of genotypic variability.  WA- Does glyphosate have short and long-term impacts on beneficial soil microbes? Wheat growers in the Pacific Northwest are concerned about the long-term use of the herbicide glyphosate (Roundup) in no-till over the last 40 years. Can this compound shift or impact microbial communities in the soil that have beneficial effects, such as arbuscular mycorrhizal fungi?  ARS and WSU scientists at Pullman, WA have initiated a series of long-term greenhouse experiments with field soils with long-term histories of glyphosate application or no previous application. They used next-generation sequencing to describe how soil microbial communities are impacted by glyphosate application. They found that glyphosate had no significant impact on bacterial communities, and that cropping system and farm location had much larger effects. When using high resolution techniques at the OTU level, out of the 4-8 thousand OTUs identified, less than 100 showed significant effects of glyphosate, and most of these were actually increased in abundance by glyphosate, copiotrophs that were favored by dying roots. More taxa from fields with a long history of glyphosate use were affected by glyphosate applications, compared to fields with no history of glyphosate use. This information is critical for growers who want to keep this important tool for no-till wheat cropping systems.  In similar studies conducted in orchard soils by ARS and WSU scientists in Wenatchee and Pullman, multi-year glyphosate applications at 2X rates using a commercial spray program in commercial orchards demonstrated no impact on composition of bacterial or fungal communities resident to rhizosphere or bulk orchard soils. WA- No-till impacts communities of fungi. No-till is being adopted by more wheat growers in the Pacific Northwest as a way to reduce soil erosion and fuel costs. However, cessation of tillage may increase some soilborne pathogens such as Rhizoctonia. Microbial communities are also shifted, and may help to suppress these diseases. ARS and WSU scientists used Illumina MiSeq to compare fungal communities in long-term no-till and conventionally-tilled plots over 3 years.  Genera such as Trichocladium and Cryptococcus were more abundant in no-till, while Cladosporium, Ulocladium and Glarea were more abundant in conventional tillage. Microbial communities are impacted by cultural practices, and by their interactions with pathogens, may suppress soilborne diseases. WA- Biosolids can shift fungal communities in soil. Biosolids are processed sewage sludge that are being applied to dryland wheat fields as a source of nitrogen.  However, it is unclear what impact these may have on soil microbial communities, and whether fungi from the human gut can persist in these biosolids.  ARS scientists at Pullman, WA, used next-generation sequencing of soil and dust samples from field-applied biosolids. They found biosolids applied to the soil significantly shifted the fungal communities both in the soil and dust, probably a result of soil fungi using the biosolids as a food source.  However, they found no evidence of any human-gut associated fungi in the samples. This information is important for assessing the safety of biosolids, especially in dust that can blow off the fields and be transported for hundreds of miles. WA- Onions are dependent on arbuscular-mycorrhizal fungi (AMF) for uptake of P. However, soils are often fumigated before planting onion crops in the Columbia Basin, which may eliminate this beneficial symbiosis. However, a survey indicated that AMF are similarly present in organic and conventional onion bulb crops. Next-generation sequencing was used to identify AMF taxa in both systems.  Diversity was not significantly different between the two systems, but the community composition was different. Claroideoglomus lamellosum, Glomus mossae and Glomus Whitfield type were the most dominant. C. lamellosum is decreased by fumigation, along with Glomus Whitfield type, but G. mossae was increased.  In terms of organic vs conventional Glomus Mo 17 seems to be decreased in organic, but G. Whitfield type was increased in organic. WA-ARS scientists at Wenatchee WA demonstrated that anaerobic soil disinfestation (ASD) employing orchard grass as the carbon input provided soil-borne disease control and improved growth of apple rootstocks in a replant nursery setting to a level equivalent or superior to pre-plant soil fumigation. The degree of growth promotion and disease suppression in response to application of ASD was influenced by rootstock genotype.  WA-With colleagues at Univ. California-Santa Cruz and the California Strawberry Commission, ARS scientists at Wenatchee WA demonstrated in preliminary field trials that mustard seed meal soil amendment in conjunction with reduced rate chloropicrin fumigation (1/2 rate) was as effective as full rate chloropicrin soil fumigation in promoting growth and yield of strawberry on a site where Fusarium wilt was the dominant yield limiting factor.  Objective 2 To understand how microbial populations and their gene expression are regulated by the biological (plants and microbes) and physical environment and how microbes influence disease. ME- Studies signaling molecules that regulate the zoosporic germination and infection of Phytophthora erythroseptica. This will help us to understand how the pathogen behave in the natural environment and how we can manipulate based on the chemistry. Potential application will be to apply homologous compound to change the pathogen germination time in order to avoid plant infection. MS- We characterized the genome sequence of the classical PGPR Bacillus subtilis UD1022. We also showed that application of UD1022 leads to minimal ingression by food-borne pathogens in leafy green species. WA- We are investigating how temperature and water potential affect the growth and reproduction of Rhizoctonia and Fusarium, two pathogens causing root and crown rot of wheat. Fusarium culmorum and F. pseudograminearum are capable of growth at -7 mPa, while Rhizoctonia solani AG-8 was restricted beyond -1 mPa.  At optimal temperatures of 20-25 C, macroconidia of both Fusarium species was capable of germination even at -9 MPa. For both Fusarium species, growth and germination were higher at -1 and -2 MPa, compared to 0 MPa, indicating a stimulation in growth under higher conditions. Cubic and quadratic models were fit to look at the interactions between temperature and moisture.   This information is needed to model distribution of these pathogens under future climate change scenarios. Objective 3. Implement sustainable management strategies for soilborne pathogens that are compatible and integrated with good soil health practices. CA- The Pacific shoot-gall nematode (Anguina pacificae) causes considerable damage on putting greens with annual bluegrass (Poa annua) along the Northern California coast. After the withdrawal of Nemacur (a.i. fenamiphos), a botanical Neem product has become the current standard to mitigate the disease albeit at a high application rate and frequency. During 2015-16 we conducted several trials on A. pacificae-infested golf courses along the Monterey, Santa Cruz and San Mateo coast to evaluated Indemnify (a.i. fluopyram) at various rates and application intervals in comparison to biweekly Neemix 4.5 (a.i. azadirachtin) application. One to two applications of Indemnify typically improved turf quality within 4 weeks compared to the non-treated control. It provided season-long protection against P. annua shoot-gall disease. Neemix 4.5 did not reduce A. pacificae population nor did it improve the turf quality. ME- Studied the effect of crop rotation on pink rot of potato. This is the third year of the project. Under rotations with different crops, plant yield and disease severity were measured. Soil was further analyzed on microbial communities that associate with soil health. By reaching out to potato growers, this information has been distributed to help them have better cultural practices. A Master’s thesis has been submitted on this project. The information was presented on American Phytopathological Society Northeastern Division Annual Meeting, growers field days, and extension meetings. MS- The classical PGPR Bacillus subtilis UD1022 (Ref: 6) is now being licensed by the commercial company for seed applications. NE- Repeated greenhouse experiments were completed to evaluate the degree to which a strain of Lysobacter enzymogenes (C3), a biological control bacterium used against soilborne fungal pathogens and nematodes, can multiply in the rhizospheres of various economic crops (corn, wheat and soybean) and cover crops commonly planted in the Midwest. Strain C3 was found to multiply in the roots systems of certain plant species following seed treatment with the bacterium, with highest populations of the bacterium being detected in the roots of cereal rye, and significantly lower populations in the roots of other plants, e.g. wheat. The finding that root colonization by Lysobacter enzymogenes is plant species dependent indicates that the microbe-plant interaction needs to be considered in order to develop an effective biological control product. The effectiveness of the bacterium in multiplying in the root system of cereal suggests that the bacterium can be delivered to cereal rye via seed treatment and that the plant’s root system subsequently serves as an environment for growth of the bacterium. OR- Parke’s group conducted research on the sustainable management strategy of soil solarization to disinfest raised beds of plant pathogens and weeds. Field trials were conducted in three nurseries in 2016: a forest tree seedling nursery in Mima, WA, a horticultural nursery in Yamhill, OR, and a horticultural nursery in Boring, OR. Populations of soilborne pathogens Fusarium oxysporum, Pythium spp., and Agrobacterium spp. were monitored, along with weed emergence, soil temperature, and volumetric soil moisture. OR-Parke’s group used the Illumina MiSeq to investigate Oomycete communities in nursery irrigation systems in OR, CA, and SC based on direct DNA extraction from water filters and compared results with rhododendron leaf baiting. Baits detected a subset of plant pathogenic Phytophthora species whereas Illumina MiSeq detected plant pathogens as well as saprophytic species. Direct extraction from water filters was more sensitive at detecting low inoculum levels than was baiting. OR- Widespread mortality observed in horticultural nurseries in container-grown conifers prompted Parke’s lab to conduct Koch’s Postulates to demonstrate that Juniperus communis is a host for Phytophthora lateralis. Nursery isolates were found to be the North American genotype and no evidence for mefanoxem resistance was detected. WA- Resistance to cereal cyst nematode found in adapted wheat lines.  Cyst nematodes are among several types of plant-parasitic nematodes that reduce yields in Pacific Northwest dryland wheat fields, accounting for about $51 million in annual losses. There is presently no chemical controls or resistant varieties to control this pathogen. ARS scientists at Pullman, Washington screened advanced lines in the greenhouse and field plots. They have identified a number of resistant varieties, including SY Steelhead, Svevo, ARS Crescent and ARS Selbu, the latter three developed by our Unit. These can be immediately used by growers to manage this disease.  In addition, discovery of this resistance will aid breeders in more quickly developing further varieties, without having to breed out undesirable characters present in poorly adapted germplasm. WA- 7th Spinach Fusarium Wilt Soil Bioassay: In the winter of 2015-16, soil samples from >30 fields in northwestern Washington were assayed for the level of risk of Fusarium wilt for spinach seed crops to be planted in 2016. To date, >240 fields have been tested for relative risk of this disease because of the highly conducive nature of acid soils in this region to Fusarium wilt, which can cause complete losses of spinach seed crops planted with susceptible parent line(s), even following 15 + years of rotation out of spinach. Objective 4. Provide outreach, education, extension and technology transfer to our clients and stakeholders- growers, biocontrol industry, graduate and undergraduate students, K-12 students and other scientists. CA- The PI provided 14 science-based presentations about plant-parasitic nematodes, the diseases they cause and potential IPM practices to mitigate plant damage and crop loss. My clientele included University of California farm, horticulture and IPM advisors, private pest control advisors, growers, golf course and sports facility superintendents, agrochemical and biocontrol industry researchers, commodity representatives, USDA and CDFA scientists, ag commissioner personnel, Master gardeners as well as the general public (see under presentations). ME: Published 4 peer-reviewed papers and 12 articles in extension, proceeding, and online journals. Delivered 3 posters and 12 oral presentations. Attended 12 meetings and 2 field days. OR- Parke and colleagues developed an online soil solarization grower tool to predict the length of time necessary to solarize soil to kill two Phytophthora species. Parke presented findings to nursery growers, agricultural professionals, and extension personnel at the Western Disease Conference. Presentations were also made to growers and practitioners at a meeting of the Western Forestry and Conservation Nursery Association and the Intermountain Container Seedling Growers’ Association, and at the Native Western Plant Conference sponsored by the Western Forestry Conservation Association. An article on solarization was published in the Feb. 2016 issue of Digger, the nursery grower magazine published by the Oregon Association of Nurseries (circulation 8,000).  NY- In 2016, Smart gave 7 talks to growers, extension educators and industry representatives on strategies to control Phytophthora blight.  These included talks at the NY state fruit and veg expo, talks at winter grower meetings in western and eastern NY, and summer twilight meetings.  Additionally, Smart presented a webinar during the winter of 2016 to beginning vegetable growers. Undergraduate research experience.  The Plant Pathology and Plant-Microbe Biology Section on the Geneva Campus of Cornell University established a summer scholars program to increase the involvement of undergraduate researchers in applied agricultural sciences.  In 2016, 27 students presented posters at the end of the program.  Each summer, several students are involved with projects that are part of the W3147 multi-state project.  During the summer of 2016, a student in the Smart lab worked on Phytophthora capsici studying the population biology and evolution of the pathogen. Outreach to K-12 students. We have continued our outreach program to third-grade students in the Geneva City School District (Geneva, NY).  Part of this outreach includes a summer science camp, where students study different aspects of food production utilizing a garden that they plant at their school.  One week of the 5-week program focuses on the importance of healthy soil to producing healthy vegetables. WA- In 2016, researchers from WA presented over 40 extension talks, field days, workshops/clinics and special consultations in relation to soilborne diseases. Paulitz provided consultation on a regular basis for the WSU Disease Diagnostic Clinic and for cereal and oilseed growers to diagnose diseases, and du Toit diagnosed 99 vegetable and seed crop samples. ARS Wheat Health, Genetics and Quality Research Unit continues to provide outreach to K-12 Native Americans, including the Colville Confederated Tribes, the Spokane Tribe, and the Kalispell Tribes. They also provided science education for underserved rural areas, including LaCrosse High school, and a 3-hour workshop for the students at the WSU labs on Nov. 8, 2016.  They provided molecular biology, biochemistry and engineering training for 13 summer high school interns (June-July 2016) in ARS and WSU labs; and placement of underserved WSU undergraduates as laboratory assistants in ARS and WSU labs. WA- The USDA ARS wheat group presently is supervising 6 graduate students, co-supervising one graduate student, and on the committee of 10 others at WSU. Mazzola is mentoring three PhD students and one MSc student at WSU, one PhD student at Stellenbosch University in South Africa, and one MSc student at Cal Poly San Luis Obispo, serves on the committee of 5 other students in horticulture, soils and plant pathology at WSU. du Toit is chairing the committee of 4 MS students at WSU, and served on another 4 PhD committees at WSU and 2 MS committee at the University of Guelph, Ontario, Canada, with projects on soilborne plant pathogens.  WA- du Toit participated in three meetings/workshops in 2016 related to an NSF-AGEP grant, PNW COSMOS, held by WSU, University of Idaho, University of Montana, Montana State University, Montana Tech, Salish Kootenai College, Heritage University, and Northwest Indian College to recruit Native American students into STEM fields of study for graduate school and, ultimately, the professoriate. See: <a href="http://us14.campaign-archive1.com/?u=207ad406a1912345d2f3d85d5&id=573d001805&e=a2e8842cc8">http://us14.campaign-archive1.com/?u=207ad406a1912345d2f3d85d5&id=573d001805&e=a2e8842cc8</a> for details.  WA- Paulitz was the main coordinator and organizer of Joint Meeting of the 62st Annual Conference on Soilborne Pathogens, Parlier, California, March 22-24, 2016. This annual meeting attracted over 100 industry, academic, government, regulatory, and student attendees.  WA- du Toit helped organize the Annual Meeting of the Pacific Division of the American Phytopathological Society in La Conner, WA on 28-30 June 2016 with record attendance of 148 researchers, extension specialists, students, private industry representatives, regulatory agents, and other stakeholders from across the western states, with many papers and posters on soilborne plant pathogens.

Publications

Impact Statements

We used probit regression models to show that there was a strong relationship between pre-planting population levels of the fungus Dactylella oviparasitica in sugar beet soils in the Imperial Valley (CA) and post-planting levels of the nematode Heterodera schachtii. We expect that this will lead to the development of new cropping decision models, which we anticipate will lead to higher crop yields and profitability for the growers.

Date of Annual Report: 01/19/2018

Report Information

Annual Meeting Dates: 12/01/2017 - 12/02/2017
Period the Report Covers: 10/01/2016 - 09/30/2017

Participants

Adesemoye, Tony (tony.adesemoye@unl.edu);
Becker, Ole (obecker@ucr.edu) – University of California, Riverside;
Borneman, James (borneman@ucr.edu) – University of California, Riverside;
Friesen, Maren (m.freisen@wsu.edu) - Washington State University;
Gachomo, Emma (emma.gachomo@ucr.edu) – University of California, Riverside;
Hao, Jianjun (jianjun.hao1@main.edu) – University of Maine;
Lavine, Lavine (lavine@wsu.edu), Administrative Advisor – Washington State University;
Paulitz, Tim (paulitz@wsu.edu) – USDA ARS, WA;
Ploeg, Antoon (antoon.ploeg@ucr.edu) – University of California, Riverside;
Poleatewich, Anissa (anissa.poleatewich@unl.edu) – University of New Hampshire;
Yuen, Gary (gyuen1@unl.edu) – University of Nebraska

Brief Summary of Minutes

Meeting host and local arrangements: James Borneman

Meeting Chair: James Borneman

Meeting Secretary: Gary Yuen

Meeting minutes: Gary Yuen

The meeting started at 8:30 AM with the chair’s welcome and introduction of attendees.

Laura Lavine, attending via telephone, provided information on research funding opportunities and on how to report impacts.

The minutes from the 2016 meeting were approved.

Gary Yuen volunteered to be meeting secretary. He will be meeting chair for the 2018 meeting pending project renewal.

The 2018 meeting will be held at UC Riverside on Nov. 30, 2018. The possibility for members who cannot attend that meeting in person to connect via Zoom will be investigated.

Progress Reports:

James Borneman reported on soil microbiome research in connection with Huanglongbing disease of citrus.

Antoon Ploeg reported on strains of Meloidogyne spp. breaking Mi resistance to root knot nematodes in tomato.

Tim Paulitz reported on investigations into the effects of glyphosate on fungal communities.

Gary Yuen described new research studying in vivo expression of biocontrol-related genes by Lysobacter enzymogenes.

Ole Becker reported on a survey of Brassica production fields for nematode populations and the identification of nematode suppressive soils.

Tony Adesemoye reported on the discovery of new biocontrol agent strains of Burkeholderia ambifaria and Bacillus spp.

Emma Gachomo reported on Pythium suppressive soils in connection with carrot cavity spot disease.

Jianjun Hao reported on epidemiological investigations on soft rot and blackrot in potato caused by Dickeya dianthicola

Maren Friesen reported on studies into the microbiome of rhizobium nodules in association with native legumes.

The members revised sections of the project renewal proposal which had been drafted by Tim Paulitz. The revision will be distributed for additional input. Portions of the renewal proposal were previously entered into the NIMSS system, and a temporary number (W4147) was assigned for the new project.

Before adjourning the meeting, the members expressed their appreciation to Tim Paulitz for his great leadership in writing the new project proposal. The members also thanked James Borneman for his fine job in making local arrangements.

The meeting was adjourned at 4 PM.

Accomplishments

Objective 1 To identify and characterize new biological agents, naturally suppressive soils, cultural practices, and organic amendments that provide management of diseases caused by soilborne plant pathogens. CA- One of the long-term goals of our research programs is to develop more sustainable strategies to manage soil-borne plant pathogens. To accomplish this, we are endeavoring to understand soils that naturally inhibit plant pests and disease, termed suppressive soils. Key steps in realizing the potential of these soils are to identify the causal organisms and then understand the agronomic and environmental factors that enable them to function. Armed with such knowledge, it should be possible to develop effective and sustainable pest management strategies through the application of the organisms and through agronomic practices that influence their populations. To date, we have identified several fungi involved in suppressing sugarbeet cysts nematodes (Dactylella oviparasitica and Fusarium oxysporum) and root-knot nematodes (Pochonia chlamydosporium and a Tetracladium sp.). We have also identified new Dactylella oviparasitica phylotypes, which suggests that these fungi may represent a large group of potentially effective biological control agents, and which can be found worldwide. In addition, we have determined that soils with no detectable Dactylella populations can harbor this fungus, and which can dramatically increase during one host cropping cycle. This is a key finding, suggesting that standard methods for screen soils for putatively protective microorganisms will not work. We have also presented a new approach and supporting data for using Dactylella population densities in planting decisions models.  CA- We used probit regression models to show that there was a strong relationship between pre-planting population levels of the fungus Dactylella oviparasitica in sugar beet soils in the Imperial Valley (CA) and post-planting levels of the nematode Heterodera schachtii. We expect that this will lead to the development of new cropping decision models that will enable growers to be create and maintain soils that suppress H. schachtii, which we anticipate will lead to higher crop yields and profitability for the growers.  CA-We are currently performing similar experiments as described just above to examine soils used to grow members of the Brassicaceae along the west coast of California between Los Angeles and San Francisco, toward the same goal of developing new cropping decision models that will enable growers to be create and maintain soils that suppress H. schachtii, which we anticipate will lead to higher crop yields and profitability for the growers.  CA- The sugar beet cyst nematode Heterodera schachtii is found in California in many Cole-cropping areas and in the Imperial Valley in sugar beet fields. Since the temporary ban of 1,3-D in 1992, nematicide use in the Cole-crop producing areas has dramatically dropped. A survey of 150 randomly selected Brassica fields in the Salinas Valley and Santa Barbara County found only 1/3 of fields infested with this nematode despite typically narrow crop rotations with susceptible crops. Moreover, very few soils had H. schachtii population densities that would predict a significant crop impact. When these soil samples were tested for biological cyst nematode population suppression, at least 15 soils tested positive.  KS- Soil microbial activity changed between a susceptible (KanMark) and a resistant (Everest) winter wheat cultivar in southeast Kansas. The total microbial biomass and microbial biomass of beneficial fungal populations (actinomycetes and arbuscular mycorrhizal fungi (AMF)) were all less in the soil from KanMark plots in comparison to Everest plots. This one year of data indicates Everest may be able to enhance beneficial microorganisms in the soil, and indicates a potential mechanism of reduced soil-borne disease infestation in Everest.  NE- K20, a derivative of a kanamycin A, a pharmaceutical drug originally identified from a bacterium, has in vitro activity against a wide range of fungi, including plant pathogens. K20 was demonstrated in greenhouse and field studies to suppress head blight in wheat caused by Fusarium graminearum.  NE- More than 150 potentially beneficial bacterial isolates belonging to the Bacillus group and 10 Trichoderma (fungi) isolates were collected this project year and 30% of them has been evaluated for growth promotion and/or antagonism against fungal pathogens in vitro.  NE-Selected isolates among those collected in previous years and examined in vitro were evaluated this year in greenhouse experiments and two of the lead strains were evaluated in the field for effectiveness in controlling root rot on corn, wheat, and soybean caused by Rhizoctonia solani.  NE- During in vitro inhibition tests of newly isolated bacteria and fungi against pathogenic strains of Fusarium spp., one strain of Burkholderia ambifaria, one strain of Bacillus simplex, and five strains of Trichoderma were selected as top strains. In the greenhouse studies, 15 -65% reduction in plant disease was achieve by using the beneficial organisms while 35 - 95% reduction in pathogen growth was achieved during laboratory in vitro assays. Findings have been submitted for publication in a peer reviewed journal and the manuscript is currently in press.  NE- Additionally, 12 plant growth promoting rhizobacteria (PGPR) Bacilli strains were evaluated for the ability to enhance the growth of corn, soybean, and wheat in the absence of plant pathogens and were characterized in the laboratory to determine if any associated physiological traits could be used to predict their ability to enhance plant growth. The physiological traits studied for the Bacilli strains included phosphate solubilization; the production of biosurfactants, siderophores, proteases, and auxins.  NE- In the growth promotion study, seed treatment with Bacillus megaterium R181, B. safensis R173, B. simplex R180, and Paenibacillus graminis R200 increased the growth of all test crops compared to water-treated controls. The four strains increased shoot mass by 93-126% compared to the controls and increased root mass by 127-197%. Strains differed in their responses to tests for physiological trait and there was no single physiological trait found to be predictive of growth-promotion efficacy of the bacterial strains. The findings are being prepared for submission to a journal for publication.  NE- Experiments were initiated to characterize the soil microbial communities in fields with continuous cropping of corn as compared to conventional crop rotation. Because corn root diseases had not been noted previously in the continuously cropped fields, the soil in those fields are presumed to be suppressive to corn root pathogens, perhaps due to their unique microbial communities. Samples of soils from Nebraska fields that have been continuously cropped with corn for 40 or 103 years with no major histories of root diseases were collected at several time periods and the analysis is ongoing. Some of the DNA extraction done previously had low quality and re-extraction was carried out in 2017. Following the completion of microbial DNA extraction, a library has been developed and quality-checked. Samples have been sent to Novogene and DNA sequence analysis for microbial community profile is in progress.  NJ- We are exploring a process termed ‘rhizophagy cycle’ where bacteria alternate between a free-living soil phase and a root intracellular/endophytic phase. The bacteria that are plant symbionts often show ability to suppress disease in the free-living phase—and in the intracellular phase the bacteria are oxidized by the host to extract nutrients from them. Patent applications for microbes that control diseases in crop plants are listed under “Patents” in the Publication list.  NY- Change in a Phytophthora capsici population over time. To identify control strategies, it is important to know how a pathogen population in a field is changing over time. Sexual, endemic populations of the heterothallic Phytophthora capsici continue to devastate vegetable crops in the northeast. In many instances, flooding events introduced P. capsici into fields with no prior history of the pathogen. Common occurrence of both A1 and A2 mating types results in production of oospores, and consequently persistent, overwintering populations. Further, prior research in our lab provides evidence for localized populations, with little to no gene flow between fields in the northeast. To understand the dynamics of these isolated, sexual populations of P. capsici, a restricted access research farm in Geneva, NY, with no prior history of P. capsici, was inoculated in 2008 with two isolates of opposite mating type. Approximately, 50 isolates were sampled each year from 2009-17 from a variety of susceptible plant species. To parallel the field study, F1 single-oospore progeny were isolated from a cross performed in the lab between the same founding parents. These F1 provide a frame of reference for the field population in which generation and relatedness of isolates are unknown. Isolates from 2009-2013 were analyzed using genotyping-by-sequencing (GBS), which simultaneously identifies and scores single nucleotide polymorphism (SNP) markers, resulting in approximately 30,000 SNP markers distributed throughout the genome. Last year we reported that the founding F1 oospores were recovered for three years following initial inoculation, but not since that time. We have a large number of isolates from 2015 and 2017 (with fewer from 2014 and 2016 due to hot and dry weather). We have single zoospore isolates and DNA extracted from the 2014-2015 isolates, and are completing single zoospore isolation and DNA extraction from 2017 samples. Once the 2017 samples are complete we can submit 95 samples (one plate) for GBS sequencing and will compare these samples to the earlier collections. Once a field is infested with both mating types of P. capsici, it is currently unfeasible to eradicate the pathogen. Thus, it is essential to understand both the founding and long-term trajectories of P. capsici populations to improve management strategies.  NY- Industrial hemp microbiome. Cornell began researching industrial hemp in 2016, and in 2017 the Smart lab started a project to assess the microbiome of the rhizosphere, roots, flowers and leaves of industrial hemp cultivar Anka at 5 field locations in New York. Samples were collected, DNA has been extracted, and PCR amplicons (of portions of the rDNA) for both fungi and bacteria are currently being sequenced. Once we have a better idea of the microbiome we will then be able to look at how these microbes may influence disease. In 2018 we plan to have a more comprehensive study on how age, variety, cultivar and environment impact the microbiome.  WA- Glyphosate application changes the succession of fungi in roots. The herbicide glyphosate (Roundup) is widely used by wheat growers in the PNW, but can cause increased root diseases through the green bridge effect, by favoring pathogens in dying roots of volunteer and weeds. However, other fungi may displace the pathogens, resulting in less disease if planting is delayed by 2-3 weeks. ARS scientists, using next-generation sequencing, showed that unexpected taxa such as Pythium volutum and Myrmecridium were dominant components in dying roots, but were displaced by Cadophora, Exophiala, and Fusarium, which may be key competitors of pathogens that proliferate soon after glyphosate application. This work leads to a greater understanding of fungal dynamics of green bridge management, which is a major tool for growers to reduce the impact of root pathogens such as Rhizoctonia and Pythium.  WA-Biosolids can shift fungal communities in soil. Biosolids are processed sewage sludge that are being applied to dryland wheat fields as a source of nitrogen. However, it is unclear what impact these may have on soil microbial communities, and whether fungi from the human gut can persist in these biosolids. ARS scientists at Pullman, WA, used next-generation sequencing of soil and dust samples from field-applied biosolids. They found biosolids applied to the soil significantly shifted the fungal communities both in the soil and dust, even when applied a few years before, but only favored a small number of genera of soil fungi which used the biosolids as a food source. This information is important for assessing the safety of biosolids, especially in dust that can blow off the fields and be transported for hundreds of miles.  WA-Salicaceae endophytes with biocontrol potential. With new collaborator Dr. Sharon Doty, University of Washington, Seattle, USDA-ARS showed that 13 bacterial or yeast endophytes of Salicaceae had in vitro activity against at least two of the following soilborne fungal pathogens: Rhizoctonia solani AG-8, Fusarium culmorum, Gaeummanomyces graminis var. tritici and Pythium ultimum. While the endophytes were generally sensitive to Veg’lys, a commercial Allium formulation being explored for small-scale soil fumigation, the growth of two strains was stimulated by the formulation, and eight strains demonstrated the ability to adapt and grow on Veg’lys at IC100 concentrations normally inhibitory to the strains. These and other findings indicate that the endophytes have the potential to protect host roots against biotic stress in the soil and have remediation properties.  WA- Optimizing limestone amendments to suppress Fusarium wilt in spinach seed production. The 10- to 15-year rotation required to minimize losses to Fusarium wilt is the primary constraint on spinach seed production in the maritime Pacific Northwest, the only region of the USA suitable for this cool-season, daylength-sensitive crop. A 4-year field trial was completed to assess the potential for annual applications of agricultural limestone at 0, 2.24, and 4.48 tons/ha for three years prior to a spinach seed crop to improve Fusarium wilt suppression. Three successive annual applications of 4.48 tons limestone/ha reduced mid-season wilt incidence by an average of 20%, increased spinach biomass by 33%, and increased marketable spinach seed yield by 45% compared to plots amended once with the same rate of limestone in the spring of planting. The suppressive effect increased with increasing rate of limestone amendment. The effects on seed yield were greatest for the partially resistant female line, followed by the moderately susceptible and highly susceptible female lines. The results demonstrate that annual applications of agricultural limestone on acid soils of the maritime Pacific Northwest USA can enhance suppression of spinach Fusarium wilt, potentially reducing the required rotation interval by as much as 50%, thereby doubling the capacity for spinach seed production in the USA.  WA-Effect of Contans WG and burial on survival of sclerotia of Sclerotinia sclerotiorum in the Columbia Basin of central Washington. White mold, caused by Sclerotinia sclerotiorum, is the main disease affecting sunflower seed crops in central Washington. A microplot trial assessed the effects of drenching Contans WG (Coniothyrium minitans, a mycoparasite of S. sclerotiorum) at 0, 0.56, and 4.48 kg/ha on survival of sclerotia on the soil surface or buried 15 cm deep. In plots not drenched with Contans WG, <10% of buried sclerotia were viable after 7 months vs. >70% for surface sclerotia. Contans WG reduced survival of surface sclerotia, not buried sclerotia, but only 12 months after application. Results were similar for a repeat trial. Contans WG also was applied by spray boom at 0 and 4.48 kg/ha to residues in large, replicated plots after harvest of a sunflower seed crop with >50% incidence of white mold. Viability of sclerotia in buried residues decreased faster than that of sclerotia in surface residues. The Contans WG application had no effect on survival of sclerotia in infested crop residues or sclerotia sampled from soil after residues had decomposed. Contans WG only reduced survival of sclerotia on the soil surface, and was never as effective as burial at reducing sclerotium survival.  Objective 2 To understand how microbial populations and their gene expression are regulated by the biological (plants and microbes) and physical environment and how microbes influence disease.   NE- The biocontrol bacterium Lysobacter enzymogenes strain OH11 was shown to possess three genes coding for unique Ax21-like proteins (Lsp). By comparing the wildtype OH11 with mutant strains having a single or combination of lsp genes deleted, the Lsp proteins were found to be involved in positive regulation in the synthesis of HSAF an antibiotic involved in the biocontrol activity of L. enzymogenes.  NE- Methodology using qPCR was developed to study the expression of key biocontrol genes by L. enzymogenes during rhizosphere colonization. Preliminary experiments involving bacteria applied to soybean grown in growth pouches revealed different temporal patterns for expression of genes involved in biosysnthesis of HSAF, glucanases, chitinases.  NE-The role of type 4 pili (T4P) production in rhizosphere colonization by L. enzymogenes was investigated by comparing populations of a mutant strain defective T4P production with populations the wildtype OH11 established on soybean root tips following seed treatment. The mutant was significantly reduced in colonization of root tips compared to the wildtype, suggesting that attachment and/or surface motility, both dependent on T4P, are critical processes for functioning of the biocontrol agent in the environment.  NY- Optimization of a super paramagenetic nanoparticle technique for extracting DNA from soil for microbe detection. An economical method for extracting nematode DNA from 100 g of soil was developed to facilitate nematode detection and quantification, and tested using the Northern root-knot nematode, Meloidogyne hapla. The method utilized enzymatic laundry detergent lysis, Fe3O4 super paramagnetic iron oxide nanoparticle (SPION) capture, and polyvinylpolypyrrolidone (PVPP) purification. Resultant DNA from this SPION capture method was approximately 100-fold less but of similar quality to DNA obtained from a standard phenol procedure and a commercial DNA extraction kit. An addition of ten mg of nanoparticles to the extraction lysate was identified to maximize DNA yield while minimizing co-capture of contaminants. The detection limit of the SPION capture method was approximately 100 nematodes per 100 g soil. The SPION capture method extracted nematode DNA from mineral soils but requires further optimization for extraction from high organic matter (i.e. ‘muck’) soils.  WA-Dynamics of phenazine-1-carboxylic acid (PCA) in the wheat rhizosphere. PCA produced by biocontrol bacteria has a key role in the suppression of soilborne fungal root pathogens, but the basis for its persistence in the rhizosphere of dryland wheat throughout the growing season is unexplained. ARS scientists, with collaborators at Washington State University, determined that PCA is synthesized mainly early in the season, when the soil is still moist, but that biosynthesis can continue even as soils dry and become arid. Furthermore, persistence cannot be explained by failure to undergo degradation in arid soils. These findings are important because PCA produced in the rhizosphere can suppress Rhizoctonia solani, an important pathogen of dryland wheat.  WA-Phenazine-1-carboxylic acid (PCA) influences biofilm development and turnoverof rhizobacterial biomass in a soil moisture-dependent manner. Bioactive compounds produced in the rhizosphere profoundly influence plant health and development, but their impact on soil nutrient dynamics and organic matter is poorly understood due to spatial and biochemical heterogeneity. ARS scientists, with collaborators at Washington State University and Pacific Northwest National Laboratory, imaged wheat roots grown in soil mesocosms inoculated with derivatives of the PCA-producing rhizobacterium. PCA exerted moisture-dependent effects on biofilm development and the turnover of nutrients and organic matter derived from rhizobacterial biomass. These results are important because they show that key taxa within the phytobiome significantly impact rhizosphere function.  WA-Root pathogens of wheat can grow under extremely dry conditions. Climate change scientists are interested in the future distribution of wheat pathogens and pests under 2050 scenarios, but little is known about how root pathogens respond to temperature and moisture. ARS and WSU scientists conducted a series of lab and microcosm experiments with Fusarium spp. that cause crown rot and Rhizoctonia spp. that cause root rot. They showed that sensitivity to moisture varies with temperature. Fusarium species were capable of growing and germinating under very dry conditions- down to -7 MPa, but Rhizoctonia spp. did not grow much below -2 MPa. This information is important for growers to determine future risk of these diseases, and explains why Fusarium crown rot is exacerbated under drought conditions.  Objective 3. Implement sustainable management strategies for soilborne pathogens that are compatible and integrated with good soil health practices.   KS- A high-glucosinolate mustard plant was used as a cover crop to control charcoal rot infestation in soybeans. Charcoal rot is caused by the fungus Macrophomina phaseolina. There were significantly fewer colony forming units (CFU) of M. phaseolina in both soil and plants in treatments with mustard seed than in those without. The number of CFUs increased in all plots from spring to fall, but remained significantly less in plots with mustard cover crop.  NY- Rolled cereal rye mulch for white mold control. White mold caused by the fungus, Sclerotinia sclerotiorum is a devastating disease of bean. This study quantified the efficacy of a rolled-crimped cereal rye mulch on agronomic variables, weed and disease control in a replicated dry bean (cv. Eclipse) field experiment. The experiment was replicated in the same field using soybean (cv. Viking). Cereal rye mulch significantly reduced weed populations and incidence of white mold without deleteriously affecting yield. In soybean, the rye mulch had an inhibitory effect on plant populations early in the season, also reflected in crop biomass (19 July) and yield components. Populations and biomass of broadleaf, grass, and total weeds in the soybean crop were not significantly affected by the rye mulch. This is likely due to the denser soybean canopy compared to the dry bean canopy, which may have suppressed overall weed populations. The inhibitory effect of rye mulch on the incidence of S. sclerotiorum carpogenic germination resulting in functional apothecia in soybean and black bean is promising. The significantly higher incidence of carpogenic germination resulting in nonfunctional apothecia (long stipes that failed to produce the apothecial disc) is likely a result of the reductions in light reaching the sclerotia. This effect may also contribute to reducing soilborne sclerotial inoculum as these sclerotia will expend energy in stipe production and become nonviable. The incidence of white mold was significantly reduced in cereal rye plots planted to soybean, but not black bean, most likely due to the crop not reaching canopy closure and reducing disease risk. Taken together, results highlight the potential multidisciplinary benefits of rye mulch for directly harvested dry bean production.  WA-Resistance to cereal cyst nematode found in adapted wheat lines. Cyst nematodes are among several types of plant-parasitic nematodes that reduce yields in Pacific Northwest dryland wheat fields, accounting for about $51 million in annual losses. There is presently no chemical controls or resistant varieties to control this pathogen. ARS scientists at Pullman, Washington have developed a greenhouse method to screen advanced and early generation lines, over 500 in 2016. They have identified a number of resistant varieties club, soft white winter and soft durum lines from ARS breeding programs, including ARS Crescent, Selbu, Cara, and Pritchett. These can be immediately used by growers to manage this disease. In addition, discovery of this resistance will aid breeders in more quickly developing further varieties, without having to breed out undesirable characters present in poorly adapted germplasm.  WA-Assessment of arbuscular mycorrhizal fungi (AMF) inoculants for enhancing onion production in the Columbia Basin of central Washington. AMF inoculants were evaluated in field trials in central Washington to counter the potentially adverse effects of widespread soil fumigation with metam sodium on soil microbial communities and soil health. Various commercial products were applied by grower-cooperators in fields on different farms. Overall, the trials demonstrated no consistent effect of the AMF inoculants on onion stand, foliar nutrient content, biomass, pink root severity, or bulb yield, even in trials with different rates of fertilizer applied at planting to try and reduce potentially inhibitory effects of high fertilization rates on establishment of AMF in onion roots. This lack of evident effect on growth of onion plants or resistance to diseases was observed even in plots in which the AMF treatment almost doubled the amount of onion root colonization by AMF compared to that of control plots. Additional growth chamber trials were completed to assess the potential impact of soil phosphorus levels on AMF colonization of onion roots using commercial AMF inoculants. The results demonstrate the potential negative effect of higher soil P levels (40 and 80 ppm) on colonization of onion roots by AMF, and the need to assess the potential impacts of soil fertility levels on the value of using AMF inoculants in onion production.  Objective 4. Provide outreach, education, extension and technology transfer to our clients and stakeholders- growers, biocontrol industry, graduate and undergraduate students, K-12 students and other scientists.  CA- worked with a 9th grade student on his science fair. In this work, methods that were used included DNA extraction and Illumina sequencing of the bacterial rRNA ITS region.  CA-The Becker lab provided 20 presentations about plant-parasitic nematodes, the diseases they cause and potential IPM practices to mitigate plant damage and crop loss. Our clientele included University of California farm, horticulture and IPM advisors, private pest control advisors, growers, golf course and sports facility superintendents, agrochemical and biocontrol industry scientists, commodity representatives, USDA and CDFA scientists, students, faculty and other researchers from various public and private Universities and research institutions, agricultural commissioner’s personnel, Master gardeners as well as the general public (see under VI. presentations).  KS- Presentations on wheat production and management to control or reduce disease pressure were made to growers at the Spring Field Day in Parsons (Reducing the impact of Fusarium Head Blight in wheat, G. Sassenrath). Additional presentations were made to farmers at informal coffee meetings during the winter at the Columbus Research and Extension Center.  NE- G. Yuen taught units related to soil pathogen ecology, biological control concepts, application of biological control in his general plant pathology and turfgrass disease courses Short term outcome: educational opportunities relating to biological control of plant diseases were provided to approximately 100 undergraduate and 20 post-baccalaureate students.  NY- Disease management strategies for Phytophthora capsici. In 2017, Smart gave 7 talks to growers, extension educators and industry representatives on strategies to control Phytophthora blight. These included talks at the NY state fruit and veg expo, talks at winter grower meetings in western and eastern NY, and summer twilight meetings. Additionally, Smart presented a webinar during the winter of 2017 to beginning vegetable growers (she does this annually).  NY- Undergraduate research experience. The Plant Pathology and Plant-Microbe Biology Section on the Geneva Campus of Cornell University established a summer scholars program to increase the involvement of undergraduate researchers in applied agricultural sciences. In 2017, 30 students presented posters at the end of the program. Each summer, several students are involved with projects that are part of the W3147 multi-state project. During the summer of 2017, a student in the Smart lab worked on Phytophthora capsici studying the population biology and evolution of the pathogen.  NY- Outreach to K-12 students. We have continued our outreach program to third-grade students in the Geneva City School District (Geneva, NY). Part of this outreach includes a summer science camp, where students study different aspects of food production utilizing a garden that they plant at their school. One week of the 5-week program focuses on the importance of healthy soil to producing healthy vegetables. During 2017, 19 students took part in the 5 week program.  NY- Outreach activities on sustainable disease management. Pethybridge gave eight extension/outreach presentations on soilborne disease management to the broadacre vegetable industry stakeholders and growers. These presentations were meetings organized by Cornell Cooperative Extension throughout New York.  NY- Undergraduate research experience. One undergraduate student was involved in a study developing a loop-mediated isothermal amplification (LAMP) assay and comparison to PCR techniques for root-knot nematode detection.  WA- In 2017, researchers from WA presented over 30 extension talks, field days, workshops/clinics and special consultations in relation to soilborne diseases. Paulitz provided consultation on a regular basis for the WSU Disease Diagnostic Clinic and for cereal and oilseed growers to diagnose diseases, and du Toit diagnosed >100 vegetable and seed crop samples. ARS Wheat Health, Genetics and Quality Research Unit continues to provide outreach to K-12 Native Americans, including the Colville Confederated Tribes, the Spokane Tribe, and the Kalispell Tribes. This included presentations at Moses Lake in March 2017 and Lacrosse high school in Dec. 2016. They provided molecular biology, biochemistry and engineering training for 14 summer high school interns (June- July 2017) in ARS and WSU labs; and placement of underserved WSU undergraduates as laboratory assistants in ARS and WSU labs. du Toit accommodated an undergraduate intern from Northwest Indian College as part of a multi-state NSF AGEP grant to recruit Native American students into STEM fields of study.  WA- The USDA ARS wheat group supervised two graduate students, co-supervised two graduate students, and on the committee of 15 others at WSU. Mazzola is mentoring three PhD students at WSU, one PhD and 1 MSc student at Stellenbosch University in South Africa, and one MSc student at Cal Poly San Luis Obispo. du Toit is chairing the committee of 4 MS students at WSU, and is on another 4 PhD committees at WSU and 1 MS committee at the University of Guelph, with projects on soilborne plant pathogens.  WA- Paulitz was the main coordinator and organizer of Joint Meeting of the 63rd Annual Conference on Soilborne Pathogens and The 49th California Nematology Workshop, Davis, California, March 28-30, 2017. This annual meeting attracted over 150 industry, academic, government, regulatory, and student attendees. WA- du Toit spent 2 weeks in the Sacapulas region of the highlands in Quiche, Guatemala in March 2017 with the Farmer-2-Farmer program of the US Agency for International Development (USAID), assisting onion farmers with disease diagnoses and management recommendations. du Toit trained 15 USAID Technical Field Assistants and regional farmers.  Short-term outcomes  Outputs- publications and reports, both scientific and extension, see below. Websites, training sessions and workshops.  Activities- Technology transfer, extension talks, workshops and clinics, see below. Involvement in governance and leadership of professional societies and journals.  Milestones: Year 5 is in the process of being accomplished, especially for Objective 1 in describing microbial communities associated with suppressive soils, and cultural and other management techniques.

Publications

Peer-reviewed  Adesemoye, A. O., Yuen, G., Watts, D. B. 2017. Microbial inoculants for optimized plant nutrients use in integrated pest and input management systems. In Probiotics and Plant Health. Arora N.K, Mehnaz. S., and Balestrini, R. (Ed.), Microbial inoculants for optimized plant nutrients use in integrated pest and input management systems. Springer pp. 21-40. DOI 10.1007/978-981-10-3473-2. Adesemoye, A. O., Yuen, G., Watts, D. B. 2017. Microbial inoculants for optimized plant nutrients use in integrated pest and input management systems. In Probiotics and Plant Health. Arora N.K, Mehnaz. S., and Balestrini, R. (Ed.), Microbial inoculants for optimized plant nutrients use in integrated pest and input management systems. Springer pp. 21-40. DOI 10.1007/978-981-10-3473-2.  Aujla, I. and Paulitz, T. C. 2017. An improved method for establishing accurate water potential levels at different temperatures in growth media. Frontiers in Microbiology. doi: 10.3389/fmicb.2017.01497.  Becker, J.O. and B. Westerdahl. 2018. Onion/Garlic: Nematodes. Pp. 28-31. In: UC IPM Pest Management Guidelines: Onion/Garlic, UC ANR Publication 3453. <a href="http://ipm.ucanr.edu/PDF/PMG/pmgoniongarlic.pdf">http://ipm.ucanr.edu/PDF/PMG/pmgoniongarlic.pdf</a> (revision)  Carlson, MO, Gazave, E, Gore, MA, and Smart, CD (2017) Temporal genetic dynamics of an experimental, biparental field population of Phytophthora capsici. Frontiers in Genetics 8:26. doi: 10.3389/fgene.2017.00026  Deyett E, Roper MC, Ruegger P, Yang J, Borneman J, Rolshausen P. 2017. Microbial Landscape of the Grapevine Endosphere in the Context of Pierce’s Disease. Phytobiomes 1:138-149. <a href="http://onlinelibrary.wiley.com/doi/10.1111/aab.12330/full">doi:10.1111/aab.12330</a>.  Dunn, A. R., Kikkert, J. R., and Pethybridge, S. J. 2017. Genotypic characteristics in populations of Sclerotinia sclerotiorum from New York State, USA. Ann. Appl. Biol. 170:219-228.  Gatch, E.W., and du Toit, L.J. 2017. Limestone-mediated suppression of Fusarium wilt in spinach seed crops. Plant Disease 101:81-94.  Ginnan NA, Dang T, Bodaghi S, Ruegger PM, Peacock, BB, McCollum G, England G, Vidalakis G, Roper C, Rolshausen P, Borneman J. 2018 Bacterial and Fungal Next Generation Sequencing Datasets and Metadata from Citrus Infected with Candidatus Liberibacter asiaticus. Phytobiomes (in press). Irizarry I, White JF. 2017. Application of bacteria from non-cultivated plants to promote growth, alter root architecture and alleviate salt stress of cotton. Journal Applied Microbiology 122(4):1110-1120. doi: 10.1111/jam.13414.  Jaaffar, K.M., Parejko, J.A., Paulitz, T.C., Weller, D.M., Thomashow, L.S. 2017. Sensitivity of Rhizoctonia isolates from the Inland Pacific Northwest of the United States to phenazine-1-carboxylic acid and biological control by phenazine-producing Pseudomonas spp. Phytopathology. 107(6): 692-703.  Kandel SL, Firrincieli A, Joubert PM, Okubara PA, Leston ND, McGeorge KM, Mugnozza GS, Harfouche A, Kim S-H, Doty SL 2017. An vitro study of bio-control and plant growth promotion potential of Salicaceae endophytes. Front Microbiol 8: 386. doi: 10.3389/fmicb.2017.00386.  Kraus, CM, Mazo, Smart, CD, and Martin, CD (2017) Pseudomonas syringae pv. tomato isolates from New York exhibit virulence attributes intermediate between typical race 0 and race 1 strains. Plant Disease doi: <a href="http://dx.doi.org/10.1094/PDIS-03-17-0330-RE">http://dx.doi.org/10.1094/PDIS-03-17-0330-RE</a>  Lehner, M. S., Mizubuti, E., Del Ponte, E. M., and Pethybridge, S. J. 2017. Independently founded populations of Sclerotinia sclerotiorum from a tropical and temperate region have similar genetic structure. PLoS ONE 12(3):e0173915.<a href="http://dx.doi.org/10.1371/journal.pone.0173915">http://dx.doi.org/10.1371/journal.pone.0173915</a>.  Lehner, M. S., Pethybridge, S. J., Meyer, M. C., and Del Ponte, E. M. 2017. Meta-analytic modelling of the relationships of white mold incidence with soybean yield and sclerotia production in uniform fungicide trials. Plant Pathol. 66:460-468.  Lehner, M., Kikkert, J. R., Gugino, B., and Pethybridge, S. J. 2017. Fungicide sensitivity and efficacy of boscalid, fluazinam and thiophanate-methyl for white mold control in snap bean. Plant Dis. 101:1253-1258.  Liang Z., D. Lee, I. Dweikat, D. Wedin, G. Yuen, R. Drijber. 2017. Molecular diversity of arbuscular mycorrhizae in roots of Juniperus virginiana invasive to grasslands. SSSAJ 81:526-536. doi:10.2136/sssaj2016.05.0133. Michelmore, R., Coaker, G., Bart, R., Beattie, G., Bent, A., Bruce, T., Cameron, D., Dangl, J., Dinesh-Kumar, S., Edwards, R., Eves-van den Akker, S., Gassmann, W., Greenberg, J., Harrison, R., He, P., Hanley-Bowdoin, L., Harvey, J., Huffaker, A., Hulbert, S., Innes, R., Jones, J., Kaloshian, I., Kamoun, S., Katagiri, F., Leach, J., Ma, W., McDownell, J., Medford, J., Meyers, B., Nelson, R., Oliver, R., Qi, Y., Saunders, D., Shaw, M., Smart, C., Subudhi, P., Torrance, L., Tyler, B., Valent, B., Walsh, J. 2017. Foundational and translational research opportunities to improve plant health. Molecular Plant-Microbe Interactions <a href="http://dx.doi.org/10.1094/MPMI-01-17-0010-CR">http://dx.doi.org/10.1094/MPMI-01-17-0010-CR</a>  Okubara P, Kumar N, Hohenwarter L, Graham D, Kandel S, Doty SL, Micknass U, Kogel K-H, Imani J. 2017 Inhibition of fungal and. bacterial plant pathogens by VegelysTM, an Allium-based antimicrobial formulation. J Biol Nat 8(2): 40-51.  Parikh, L., Eskelson, M. J., and Adesemoye, A. O. 2018. Relationship of in vitro and in planta screening: improving the selection process for biological control agents against Fusarium root rot in row crops. Archives of Phytopathology and Plant Protection (In Press). Parikh, L., Eskelson, M. J., and Adesemoye, A. O. 2018. Relationship of in vitro and in planta screening: improving the selection process for biological control agents against Fusarium root rot in row crops. Archives of Phytopathology and Plant Protection (In Press). Paulitz, T. C., Knerr, A. J., Carmody, S. M., Schlatter, D., Sowers, K., Derie, M. L., du Toit, L. J. 2017. First report of Leptosphaeria maculans and Leptosphaeria biglobosa, causal agents of blackleg, on canola in Washington State. Plant Disease 101: 504-505. Pietro-Souza W, Mello IM, Vendruscullo S, da Silva GF, da Cunha CN, White JF, Soares MA. 2017. Structure and function of the endophytic fungi community are influenced by mercury. PLoS ONE 12(7):e0182017 ·  Poudyal-Sharma, D., Schlatter, D., Yin, C.T., Hulbert, S. and Paulitz, T. C. 2017. Long-term no-till: A major driver of fungal communities in dryland wheat cropping systems. PloS One 12: 10.1371/journal.pone.0184611. Schlatter, D. C., Yin, C., Hulbert, S. Burke, I. and Paulitz, T. 2017. Impacts of repeated glyphosate use on wheat-associated bacteria are small and depend on glyphosate use history. Applied and Environmental Microbiology: 83 np. 22 e01354-17 Schlatter, D., Kinkel, L., Thomashow, L., Weller, D. and Paulitz, T. C. 2017. Disease suppressive soils: New insights from the soil microbiome. Phytopathology 107: 1284-1297.  Shah, D. A., Dillard, H. R., and Pethybridge, S. J. 2017. Probability distributions for marketable pods and white mould in snap bean. Ann. Appl. Biol. 171:179-189. <a href="http://onlinelibrary.wiley.com/doi/10.1111/aab.12363/epdf">doi:10/1111/aab.12363</a>.  Tadych M, White JF. 2017. Endophytic microbes. Encyclopedia of Microbiology (4th Edition). Academic Press. DOI: 10.1016/B978-0-12-809633-8.13036-5  Takemoto, J., G.Y. Yuen, C.C. Jochum, C.T. Chang, Y. Kawasaki, and G.W. Miller, 2017. Suppression of wheat Fusarium head blight by novel amphiphilic aminoglycoside fungicide K20. Fungal Biology <a href="https://doi.org/10.1016/j.funbio.2017.12.001">https://doi.org/10.1016/j.funbio.2017.12.001</a>. Tancos, MA, Lowe-Power, TM, Peritore, FC, Tran, TM, Allen, C., and Smart, CD 2017 Plant-like bacterial expansins play contrasting roles in two tomato vascular pathogens. Molecular Plant Pathology DOI: 10.1111/mpp.12611  Thompson, A.L., Mahoney, A.K., Smiley, R.W., Paulitz, T.C., Hulbert, S., Garland Campbell, K.A. 2017. Resistance to multiple soil-borne pathogens of the Pacific Northwest is colocated in a wheat recombinant inbred line population. G3,Genes/Genomes/Genetics 7:1109-1116.  Verma SK, Kingsley K, Bergen M, English C, Elmore M, Kharwar R, White JF. 2017. Bacterial endophytes from rice cut grass (Leersia oryzoides L.) increase growth, promote root gravitropic response, stimulate root hair formation, and protect rice seedlings from disease. Plant and Soil. DOI:10.1007/s11104-017-3339-1  Verma SK, Kingsley K, Irizarry I, Bergen M, Kharwar RN, White JF. 2017. Seed vectored endophytic bacteria modulate development of rice seedlings. J. Applied Microbiology 122: 1680-1691. Wang, R., Xu, H., Zhang, J., Yuen, G.Y., Liu, H., Qian, G., and Liu, F. 2017. Lsp family proteins regulate antibiotic biosynthesis in Lysobacter enzymogenes. AMB Express 7(1):123. doi: 10.1186/s13568-017-0421-2. Epub 2017 Jun 13. Wei Li, Long Chu, James F. White, Jr., Zhi Xiong, Xinya Li, Qiaohong Li, Sihui Zhao, Haiyan Li. 2017. Diversity and heavy metal tolerance of endophytic fungi from Chenopodium ambrosioides, a hyperaccumulator of Pb-Zn from contaminated soils. J. Plant Interactions.  White JF, Kingsley KI, Kowalski KP, Irizarry I, Micci A, Soares MA, Bergen MS. 2017. Disease protection and allelopathic interactions of seed-transmitted endophytic pseudomonads of invasive reed grass (Phragmites australis). Plant and Soil DOI: 10.1007/s11104-016-3169-6  White JF. 2017. Syntrophic imbalance and the etiology of bacterial endoparasitism diseases. Medical Hypothesis 104C: 14-15.  Xie J, Chen Q, Suresh P, Roy S, White JF, Mazzeo A. 2017. Paper-based Plasma Sanitizers. PNAS DOI: 10.1073/pnas.1621203114 Yin, C., Schlatter, D., Schroeder, K., Mueth, N., Prescott, A. Dhingra, A., Hulbert, S. and Paulitz, T. C. 2017. Bacterial communities on wheat grown under long-term conventional tillage and no-till in the Pacific Northwest of the US. Phytobiomes: 1: 83-90. Yuen, G.Y., K.C. Broderick, C.C. Jochum, C.J. Chen, and E.P. Caswell-Chen. 2017. Control of cyst nematodes by Lysobacter enzymogenes strain C3 and the role of the antibiotic HSAF in the biological control activity. Biological Control <a href="https://doi.org/10.1016/j.biocontrol.2017.11.007">https://doi.org/10.1016/j.biocontrol.2017.11.007</a>. Books and book chapters  Patents  U.S. patent pending No. PCT/US16/43408. (Filed July 21, 2016). “Compositions and Methods Comprising Endophytic Bacterium for Application to Grasses to Increase Plant Growth, Suppress Soil Borne Fungal Diseases, and Reduce Vigor of Weedy Competitors”. Inventors: White JF, Kowalski K, Kingsley K.  U.S. Provisional Patent Application No. 62/541,395. (Filed August 4, 2017) Compositions and Methods Comprising Endophytic Bacterium for Application to Target Plants to Increase Plant Growth, and Increase Resistance to Abiotic and Biotic Stressors. James White and Ivelisse Irizarry.  Canadian Patent Application No. 2,975,486(Filed August 4,2017) Compositions and Methods Comprising Endophytic Bacterium for Application to Target Plants to Increase Plant Growth, and Increase Resistance to Abiotic and Biotic Stressors. James White and Ivelisse Irizarry.  Extension and technical bulletins Adesemoye, A. O. 2017. Biologicals in plant disease management. NebGuide G2290, Nebraska Extension.  Adesemoye, A. O. 2017. Introduction to biological products for crop production and protection Extension Circular EC3019, Nebraska Extension.  Adesemoye, A. O. 2017. New financial assistance for organic producers. CropWatch January 6, 2017.  Adesemoye, A. O. and Klein, R. 2017. Cephalosporium leaf stripe developing in west central wheat. CropWatch May 25, 2017.  Adesemoye, A. O., Shapiro, C. A., Rethwisch, M., and Maharjan, B. Potential benefits of biological products in nutrient management. Nebguide G2294. Nebraska Extension  Hay, F. S., and Pethybridge, S. J. 2017. Anthracnose of garlic scapes in New York. Extension Bulletin.  Henrichs, B., Derie, M.L., Waters, T.D., and du Toit, L.J. 2017. The effects of arbuscular mycorrhizal inoculants on onion root colonization and growth in field trials near Connell, WA, 2016. Plant Disease Management Reports 11:V137.  Henrichs, B., Waters, T.D., and du Toit, L.J. 2017. The effect of soil phosphorus levels on colonization of onion roots by arbuscular mycorrhizal fungi, 2016-2017. Plant Disease Management Reports 11:V125.  Hsiao, C.-J., Sassenrath, G.F., Rice, C., Zeglin, L., Hettiarachchi, G. 2017. Key components of healthy soils and their role in crop production. Kansas Agricultural Experiment Station Research Reports: Vol. 3: Iss. 2.https://doi.org/10.4148/2378-5977.1385  Kikkert, J. R., and Pethybridge, S. J. 2017. Leaf disease management for table beets in New York. Cornell VegEdge 13 (15):1-3.  Koenick, L., and Pethybridge, S. J. 2017. Principles of fungicide resistance. Extension Bulletin.<a href="https://blogs.cornell.edu/pethybridgelab/files/2014/12/Principles-of-Fungicide-Resistance-w5foan.pdf">https://blogs.cornell.edu/pethybridgelab/files/2014/12/Principles-of-Fungicide-Resistance-w5foan.pdf</a>.  Koenick, L., Kikkert, J. R., and Pethybridge, S. J. 2017. Cercospora leaf spot of table beet. Extension Bulletin.  Kreis, R.A., Lange, H.W. and Smart, C.D. 2017. Evaluation of fungicides allowed for organic production on tomato leaf mold in high tunnel production, 2016. Plant Disease Management Report. Volume 11  Lange, H.W., Smart, C.D. and Seaman, A.J. 2017. Evaluation of materials allowed for organic production on downy mildew of cucumber, 2016. Plant Disease Management Report. Volume 11  Lange, H.W., Smart, C.D. and Seaman, A.J. 2017. Evaluation of materials allowed for organic production on powdery mildew of zucchini, 2016. Plant Disease Management Report. Volume 11  Lange, H.W., Smart, C.D. and Seaman, A.J. 2017. Evaluation of materials allowed for organic production on bacterial speck of tomato, 2016. Plant Disease Management Report. Volume 11 Pethybridge, S. J. 2017. Tackling root knot nematode in potato production in New York. The Potato News, Winter 2017 Edition. Empire State Potato Growers Inc. January 2017 (Page 9)  Pethybridge, S. J., Bowden, C., Gugino, B., and Kikkert, J. R. 2017. Epidemiology and management of white mold in processing snap bean in New York. Empire Expo, Syracuse, New York. 17 January 2017. Pp. 5.  Pethybridge, S. J., Hay, F. S., and Kikkert, J. R. 2017. Disentangling the foliar disease complex of processing lima bean in New York. Empire Expo, Syracuse, New York. 17 January 2017. Pp. 5.  Pethybridge, S. J., Kikkert, J. R., and Gugino, B. 2017. Improving the management of white mold in snap bean. Mid-Atlantic Fruit and Vegetable Growers Convention, Hershey, Pennsylvania. 31 January 2017. Pp. 50-51.  Pethybridge, S. J., Lehner, M., and Kikkert, J. R. 2017. Efficacy of fungicides for the control of white mold in light red kidney bean, 2016. Plant Dis. Man. Rep. 11:V106.  Sassenrath, G.F. 2017. Soil Health. Published in Montgomery County NRCS bulletin; Grass and Grain; Dirt Road Review, and other general public publications.  Sassenrath, G.F., Dotson, D. 2017. Healthy water and healthy soils: Preserving the land and water legacy of the Grand Lake Watershed with locally led conservation. Eastern Shawnee Tribe of Oklahoma.  Sassenrath, G.F., Little, C., Hsiao, C.J., Shoup, D., Lin, X. 2017a. Cover crop system to control charcoal rot in soybeans. Kansas Agricultural Experiment Station Research Reports: Vol. 3: Iss.  Sassenrath, G.F., Shoup, D., Lollato, R. 2017b. Wheat Production. Kansas Agricultural Exp. Station Res. Reports: Vol. 3: Iss. 2. <a href="https://dx.doi.org/10.4148/2378-5977.1384">https://dx.doi.org/10.4148/2378-5977.1384</a>  Smart, C., Lange, H. Kreis, R., and Tancos, M. (2017) Tomato bacterial diseases of 2016. Proceedings of the 2017 Empire State Producers Expo, Syracuse, NY. <a href="http://www.hort.cornell.edu/expo/proceedings/2017/Tomato.bact-tom.Smart.17.pdf">http://www.hort.cornell.edu/expo/proceedings/2017/Tomato.bact-tom.Smart.17.pdf</a> Smart, C., Lange, H., and Kreis, R. (2017) Managing tomato leaf mold in high tunnel production. Proceedings of the 2016 Empire State Producers Expo, Syracuse, NY. Weber, J.M., and du Toit, L.J. 2017. Efficacy of fungicides for control of white mold in hybrid sunflower seed crop in the Columbia Basin of central Washington, 2016. Plant Disease Management Reports 11:FC122. Meeting presentations and proceedings  Akinrinlola, R., Adesemoye, A. O., and Yuen G. Y. 2017 Bacillus strains as plant growth-promoting agents for the Great Plains agricultural region. Oral presentation during the Annual Meeting of the North Central Region of the American Phytopathological Society, which held at Champaign, IL. June 14-16, 2017.  Becker, J.O., A. Ploeg, and J. Nunez 2016. Evaluation of novel nematicides for control of root-knot nematodes in processing tomato. Journal of Nematology 48:302.  Becker, J.O., and J. Smith Becker 2017. 25 Years After the Discovery of Sting Nematodes in California: Summary of Research and Extension Efforts. 2017 UCR Turfgrass and Landscape Research Field Day Proceedings p. 9.  Carmody, S.M., and du Toit, L.J. 2017. Light leaf spot and white leaf spot on brassicas in the Pacific Northwest. Puget Sound Seed Growers’ Association Annual Meeting, 13 Jan. 2017, Mount Vernon, WA. (100 people)  Derie, M.L., and du Toit, L.J. 2017. Phoma betae in table beet and Swiss chard seed crops in western Washington. Puget Sound Seed Growers’ Association Annual Meeting, 13 Jan. 2017, Mount Vernon, WA. (100 people)  du Toit, L.J. 2017.Evaluating irrigation management and bactericides for internal dry scale and bacterial bulb rots of onion. Invited presentation, Pacific Northwest Vegetable Association Annual Convention & Trade Show, 15-16 Nov. 2017, Kennewick, WA. (125 people)  du Toit, L.J. 2017. Got seed? Plant pathology research and extension contributions to the Pacific Northwest Vegetable Seed Industry. Invited presentation at the Congreso LatinoAmericano de Fitopatología, 2-5 Oct. 2017, Concepcion, Chile. (200 people)  du Toit, L.J. 2017. Spinach seed crop pathology research and extension at Washington State University: Engaging principles of the U.S. Land Grant Mission to enhance production of a minor acreage, high value crop. J.E. Vanderplank Memorial Address, 50th Anniv. Congress Southern African Soc. Plant Pathologists, 15-18 Jan. 2017, Champagne Sports Resort, Drakensburg, South Africa. (~200 attendees)  du Toit, L.J. 2017. The What? Why? And How? Of Onion Disease Management in the Columbia Basin. Invited presentation at the National Onion Association Summer Meeting, 20 Jul. 2017, Richland, WA. (~150 people)  du Toit, L.J. 2017. What’s the big deal with black leg of brassicas? Invited presentation, Pacific Northwest Vegetable Association Annual Convention & Trade Show, 15-16 Nov. 2017, Kennewick, WA. (120 people)  Hsiao, C.J., Sassenrath, G.F., Rice, C.W., Zeglin, L. 2017. Temporal changes in soil microbial properties in claypan soils. American Society of Agronomy Annual Meeting, Oct. 22 – 26, 2017, Tampa, FL  Hsiao, C.-J., Sassenrath, G.F., Rice, C.W., Zeglin, L.H., Hettiarachchi, G.M. 2016. Soil microbial communities in claypan soils. #101195. American Society of Agronomy Annual Meeting. Nov. 6-9, 2016. Phoenix, AZ.  Hsiao, C.J., Sassenrath, G.F., Rice, C.W., Zeglin, L.H., Hettiarachchi, G. 2016. Soil microbial properties with depth in claypan soils of southeast Kansas. Governor’s Conference on the Future of Water in Kansas. Nov. 14-15, 2016, Manhattan, KS.  Kodati, S., Eskelson, M. J., and Adesemoye, A. O. 2017. Cross-pathogenicity of Rhizoctonia spp. isolated from multiple hosts to corn, soybean, and wheat. Oral presentation during the Annual Meeting of the North Central Region of the American Phytopathological Society, holding at Champaign, IL. June 14-16, 2017.  Kodati, S., Gambhir, N., Everhart, S., and Adesemoye, A. O 2017. Prevalence and pathogenicity of Rhizoctonia spp. from soybean in Nebraska. Poster presentation during the Annual Meeting of the American Phytopathological Society, APS, San Antonio, Texas. August 5-9, 2017.  Parikh, L., Eskelson, M., and Adesemoye, A. O 2017. Biological control of Fusarium root rot on row crops in the Great Plains using PGPR and Trichoderma species. Poster presentation during the Annual Meeting of the American Phytopathological Society, APS, San Antonio, Texas. August 5-9, 2017.  Paulitz, T. C. 2017. Effect of Glyphosate on Soil Microbes. Joint Meeting of the 63rd Annual Conference on Soilborne Plant Pathogens, Davis, California. March 28-30, 2017.  Paulitz, T. C. 2017. Washington State Report. Multistate Group Managing Plant-Microbe Interactions in Soil to Promote Sustainable Agriculture, Riverside, California. Dec 2, 2017.  Ploeg, A., J.O. Becker, J. Nunez, and S. Stoddard 2016. Performance of non-fumigant nematicides in California vegetables on Meloidogyne incognita-infested trial sites. European Society of Nematologists, 32nd Symposium Abstract Book. p. 82.  Sassenrath, G.F., Farney, J. 2017. Improving the productive capacity of claypan soils by targeting soil health. American Society of Agronomy Annual Meeting, Oct. 22 – 26, 2017, Tampa, FL  Schlatter, D. 2017. Second workshop in statistical and algorithmic challenges in microbiome data analysis. The Broad Institute of MIT and Harvard, Cambridge, MA. Sympatric interaction networks shed light on the ecology and evolution of soil microbiomes.  Schlatter, D. and Paulitz, T. C. 2017. Minimal impacts of repeated glyphosate use on wheat-associated bacterial microbiomes. American Phytopathological Society Meeting, San Antonio, Texas. Aug. 1-8, 2017  Schlatter, D. and Paulitz, T. C. 2017. Successional dynamics of fungal and oomycete communities in herbicide-killed wheat roots. American Phytopathological Society Meeting, San Antonio, Texas. Aug. 1-8, 2017.  Thomashow, L. 2017. Control of cereal root pathogens with root associated bacterial. Huazhong Agricultural University July 13, 2017.  Thomashow, L. 2017. Control of cereal root pathogens with root associated bacterial. Northwest A and F University, China, July 5, 2017.  Thomashow, L. 2017. Mechanisms and metabolites involved in biological control. Huazhong Agricultural University July 15 and 17, 2017  Wang, X., Schlatter, D., Edwards, C., Paulitz, T., Weller, D., Okubara, P. 2017. Biodiversity of native yeasts in vineyards and spontaneous alcoholic fermentation in Washington State. Washington Association of Wine Grape Growers Convention, Kennewick, WA.  Weber, J., and du Toit, L.J. White mold in sunflower seed crops. Columbia Basin Vegetable Seed Assoc. Annual Meeting, 1 Feb. 2017, Moses Lake, WA. (85 people)  Abstracts  Hansen, J. Sullivan, T., Schillinger, W. and Paulitz, T. 2017 Soil Microbial Communities of the Lind Camelina Cropping Systems Experiment WSU Field Day Abstracts.  Hansen, J. Sullivan, T., Schillinger, W. and Paulitz, T. 2017. Rhizosphere soil microbial communities of winter canola and winter wheat at six paired field sites in Eastern Washington. WSU Field Day Abstracts.  Hansen, J. Sullivan, T., Schillinger, W. and Paulitz, T. 2017. Rhizosphere soil microbial communities of winter canola and winter wheat at six paired field sites in Eastern Washington. WSU Field Day Abstracts.  Okubara P, Wang X, Schlatter D, Edwards C, Paulitz T, Glawe D. 2017. Native yeast diversity in two Washington Cabernet Sauvignon vineyards consists of common and unique species. American Society of Enology and Viticulture Annual Meeting, Bellevue, WA.  Okubara PA, Wang X, Schlatter D, Paulitz T, Edwards C, Glawe D. 2017. ITS1 vs. D2 for assessing yeast diversity in grape berries and fermentations in Washington state. Plant and Animal Genome XXV, San Diego, CA.  Schlatter, D. and Paulitz, T. C. 2017. Successional dynamics of fungal and oomycete communities in herbicide-killed wheat roots. Phytopathology 107: in press  Wang X, Elizabeth Kramer E, Glawe D, Weller D, Murray T, Okubara P. 2017. Evaluation of native vineyard yeasts of Washington State for biological control of Botrytis bunch rot of grape. American Society of Enology and Viticulture Annual Meeting, Bellevue, WA.  Wang, X., Schlatter, D C., Paulitz, T. C. and Okubara, P. 2017. Biodiversity of native yeast in vineyards and spontaneous alcoholic fermentation in Washington state. Washington Association of Wine Grape Growers Annual Meeting.  Weber, J.M., and du Toit, L.J. 2017. Effect of Contans WG application and burial of sclerotia on survival of sclerotia of Sclerotinia sclerotiorum in the Columbia Basin of central Washington. Poster 51-P presented at 2017 APS Annual Meeting, 5-9 Aug. 2017, San Antonio, TX.  Extension Talks/Field Days/Workshops/Consultations  Angelo Loffredo, Mitigation of nematode-caused crop damage with microbial metabolites and natural antagonists  Becker, J. O. New crop protection tools against plant-parasitic nematodes (presentation)  Becker, J. O. New nematicides and biologicals against the Southern root-knot nematode (presentation)  Becker, J. O. Aspergillus japonicus strain ZW1 and its toxicity against root-knot nematodes (poster).  Becker, J. O. California fresh market carrot production without fumigant nematicides? (presentation)  Becker, J. O. 2017 Pitahaya/Dragon Fruit Festival/Field Day, UC South Coast Research and Extension  Becker, J. O. 2017 Pitahaya/Dragon Fruit Production Tour, UC ANR, Escondido, Fallbrook, Bonsall, CA; August 25, 2017. Nematode Issues for Pitahaya Production (presentation)  Becker, J. O. 56th Annual Society of Nematologists Meeting. Williamsburg, Virginia, August 13-17, 2017. Combination of microbial antagonists and a seed-delivered nematicide mitigated root-knot nematode-caused disease in tomato greenhouse and microplot trials (presentation)  Becker, J. O. A student group visiting from Southwest University, China. UC Riverside, August 22, 2017. Plant Parasitic Nematodes and their enemies (presentation and Q&A)  Becker, J. O. American Phytopathological Society, Pacific Division, Riverside, CA June 27-29, 2017. Management of the shoot gall nematode Anguina pacificae on Poa annua putting greens (presentation).  Becker, J. O. California State Polytech University, Pomona, January 27, 2017. Introduction to plant-parasitic nematodes and their management (invited lecture/lab for undergraduates).  Becker, J. O. CAPCA Education CE Seminar Imperial Valley, Nov 9, 2017, Imperial Valley.  Becker, J. O. CAPCA Education Santa Ana CE Seminar, Nov 16, 2017. Biology and Control of Sting and Pacific Gall Nematodes (presentation)  Becker, J. O. Coachella Valley Farmers Educational Meeting, Indio, CA, February 15, 2017. Nematode Problems in Coachella Valley Agriculture (presentation)  Becker, J. O. Conference on Soilborne Plant Pathogens/Statewide California Nematology Workshop, UC Davis, March 28-30, 2017.  Becker, J. O. Desert Fall Crop Workshop Dec. 7, 2017, Imperial, CA. Biologicals Against Plant-Parasitic Nematodes: Hip, Hype and Hope (presentation)  Becker, J. O. Field demonstration for members of Western Education/Extension and Research Activities Committee on Integrated Pest Management. SCREC, Tustin, CA. July 25, 2017. Update on nematode management. Becker, J. O. International Carrot Conference, Bakersfield, CA, March 19-21, 2017  Becker, J. O. Multistate Research Project meeting, W3147, Managing Plant Microbe Interactions in Soil to Promote Sustainable Agriculture. Riverside, CA. Dec 1, 2017. Suppressive soils in California Cole crop fields (presentation)  Becker, J. O. Turf & Landscape Day, Agricultural Operations, UC Riverside, September 14, 2017. 25 years after discovery: Confining the invasive Sting nematode to the Coachella Valley (poster)  Becker, J. O. UC Integrated Pest Management Training 2017, San Diego, May 11, 2017 The Good, the Bad, and the Ugly: Nematodes in the Landscape (presentation).  Becker, J. O. University Extension Turf Management Certificate Course, 3 hr Webinar, UC Riverside Extension, March 15, 2017, Riverside, CA. Turf Management: Plant Parasitic Nematodes.  Borneman, J. BASF (Research Triangle Park, NC) October 4, 2017. Title is: Development of Biologically Based Strategies to Control Cyst Nematodes and Huanglongbing.  Borneman, J. UCR Microbiome Datablitz October 27, 2017.  Borneman, J. USDA CDRE Project Meeting in Riverside CA, November 13, 2017. Microbiome Analyses and Microbe Based Strategies to Manage HLB.  Borneman, J. Creating Cyst Nematode Suppressive Soils Using a Cropping Decision Model.” (presentation)  Borneman, J. Creating Cyst Nematode Suppressive Soils Using a Cropping Decision Model. Conference on Soilborne Plant Pathogens. Davis California, March 29, 2017.  Borneman, J. Improving Sugar Beet Economics, Productivity & Sustainability by Modifying the Cropping Decision Model. Sugarbeet Work Group Meeting, February 8, 2017, Holtville CA.  Borneman, J. Statistical Analysis of Microbiome Data When Samples Have Unequal Sequence Counts, UCR Department of Statistics, May 2, 2017.  Borneman, J. SurVerda Visit Meeting in Riverside CA, November 21, 2017. Microbe Based Strategies to Control Cyst Nematodes and Huanglongbing.  du Toit, L.J. 2017. 2-week volunteer project with the Farmer-2-Farmer program of the US Agency for International Development (USAID), assisting onion farmers in the mountainous Sacapulas region of Quiche, in northwestern Guatemala, with disease diagnoses and management recommendations, 13-25 Mar. 2017. Trained ~15 USAID Technical Field Assistants and regional farmers.  du Toit, L.J. 2017. 8th Annual Spinach Fusarium Wilt Soil Bioassay Open House, WSU Mount Vernon NWREC. Open house for spinach seed growers and seed company personnel to observe spinach parent lines ranging from highly susceptible to partially resistant fare in a bioassay test of soil sampled from growers’ fields to assess the relative risk of Fusarium wilt. Soil samples (5 gal/field) were received from 33 growers’ fields in Dec. 2016 ($200/field) and processed, as well as seed of 18 spinach parent lines from seed companies to screen for relative resistance to Fusarium wilt. Stakeholders view their soils in Feb. 2017 to make decisions on which fields to select for planting spinach seed crops in 2017. >270 fields in western WA have been tested since 2010.  du Toit, L.J. 2017. Trained 6 Washington State Department of Agriculture (WSDA) Seed Crop Inspectors on scouting for black leg, caused by Phoma lingam, in brassica seed crops in Washington State (oilseed, cover, and vegetable brassica seed crops), following the finding of this disease in >20 sites in dryland canola production in eastern Washington. 1-hour workshop on 20 Jul. 2017 in Pasco, WA.  du Toit, L.J. 2017. Washington Pest Control Tour of the Washington State Commission on Pesticide Registration, western WA, 17-19 Jul. 2015. Presented on vegetable seed production and research needs, including pathology research, to ~45 federal/state legislators or staff, agricultural industry representatives, WA State Depts. of Agriculture, Ecology, and Labor & Industries; WSU CAHNRS administrators, National Marine Fisheries Service, US Environmental Protection Agency, etc. on 18 Jul. in Mount Vernon, WA.  du Toit, L.J. 2017. WSU Extension Onion Field Day, 25 Aug. 2016, Skone & Connorr Farm, Othello, WA. Presented onion downy mildew, mycorrhizae, internal dry scale, bacterial bulb rots, and Iris yellow spot virus information and research updates to growers, seed industry, extension personnel, researchers, etc. (90 people).  du Toit, L.J. 2017/ Spinach Seed Health Assay Workshop in Denmark and the Netherlands: Invited to present a 4-hour lab workshop on spinach seed health testing at Aarhus University, Denmark on 7 Jun. 2017 (20 people). Workshop preceded by a tour of spinach seed crops in Denmark on 6 Jun. with spinach seed growers and personnel from all seed companies growing spinach seed in Denmark (35 people). Repeated the workshop at Pop Vriend Seeds, Andijk, the Netherlands on 9 Jun. 2017 (10 people, including 2 plant pathologists from Italy). Workshop preceded on 8 Jun. by presentations on the biology and management of necrotrophic fungal pathogens of spinach (30 people).  du Toit, L.J. Brassica light leaf spot, white leaf spot, and black leg; onion neck rot; and bacterial blight of carrot. Invited presentation to Bejo Seeds production team, 7 Nov. 2017, Mount Vernon, WA. (30 people)  du Toit, L.J. Tapping into growers’ expertise: Effective engagement in extension. One of 6 speakers in the 2-part APS webinar series (3 speakers/webinar) Fieldside Manner: Serving Plant Pathology’s Stakeholders, 18 and 25 October 2017.  du Toit, L.J. Vegetable seed crop pathology research, and the role the Washington State Commission for Pesticide Registration (WSCPR) funding plays in supporting this program. Invited presentation to WSCPR board, 24 May 2017, La Conner, WA. (12 people)  du Toit, L.J. Wilt diseases: Managing persistent pathogens in high value vegetable seed crops. Invited seminar to Department of Plant Pathology, North Carolina State University, 9 Oct. 2017, Raleigh, NC. (60 people)  Paulitz, T C. 2017. Diseases of Brassica. WSU Oilseed Cropping Systems Workshops, Hartline Jan. 26, 2017. Paulitz, T C. 2017. Diseases of Brassica. WSU Oilseed Cropping Systems Workshops, Ritzville Jan. 30, 2017.  Paulitz, T C. 2017. Diseases of Brassica. WSU Oilseed Cropping Systems Workshops Clarkston, Feb. 2 2017.  Paulitz, T. C. 2017.   Activities on Canola Diseases. Washington Oilseeds Cropping System Annual meeting  Paulitz, T. C. 2017. Research on Nematodes and Fusarium Crown Rot Washington Grain Commission Review, Pullman, Washington. Feb. 13, 2017.  Paulitz, T. C. 2017. Blackleg of canola and other canola diseases.   Field Day Presentation. Almira, WA June 27, 2017.   Paulitz, T. C. 2017. Blackleg of canola and other canola diseases.   Field Day Presentation. Colton, WA July 10, 2017.  Paulitz, T. C. 2017. Blackleg of Canola. Field Day presentation, Ralston, WA   Oct. 1, 2017  Paulitz, T. C. 2017. Effect of Glyphosate on Soil Microbes. Direct Seeders Breakfast, Colfax, Washington   Feb. 15, 2017 Paulitz, T. C. 2017. Management of Fresh Wheat Residue for Irrigated Winter Canola Washington Department of Ecology. Nov 9, 2017.  Paulitz, T. C. 2017. What’s New in Research on Soilborne Plant Pathogens. Spokane Farm Forum, Ag Expo, Spokane, Washington. Feb 8, 2017.  Pethybridge, S. J., and Kikkert, J. R. 2017. Know your enemy! Identification of plant-pathogenic fungi associated with root decay in table beet. Processing Vegetable Crops Advisory Meeting, Batavia, New York. Attendees = 80. Duration = 30 min. Total contact = 40 hours. 13 December 2017.  Pethybridge, S. J., and Kikkert, J. R. 2017. Optimizing the fungicide-based management of white mold in two varieties of snap bean. Processing Vegetable Crops Advisory Meeting, Batavia, New York. Attendees = 80. Duration = 30 min. Total contact = 40 hours. 13 December 2017.  Pethybridge, S. J., and Kikkert, J. R. 2017. Optimizing the use of Aprovia Top for management of Cercospora leaf spot in table beet. Processing Vegetable Crops Advisory Meeting, Batavia, New York. Attendees = 80. Duration = 30 min. Total contact = 40 hours. 13 December 2017.  Pethybridge, S. J., and Kikkert, J. R. 2017. Towards a durable management strategy for white mold in dry beans in New York. New York State Dry Bean Council meeting, Batavia, New York. Attendees = 60. Duration = 30 min. Total contact = 30 hours. 6 March 2017.  Pethybridge, S. J., Bowden, C., Gugino, B., and Kikkert, J. R. 2017. Epidemiology and management of white mold in processing snap bean in New York. Empire Expo, Syracuse, New York. Attendees = 80. Duration = 30 min. Total contact = 40 hours. 17 January 2017. Pethybridge, S. J., Hay, F. S., and Kikkert, J. R. 2017. Disentangling the foliar disease complex of processing lima bean in New York. Empire Expo, Syracuse, New York. Attendees = 80. Duration = 1 h. Total contact = 80 hours. 17 January 2017.  Sassenrath, G. F. Charcoal Rot Suppression. <a href="https://www.ksre.k-state.edu/news/radio-network/agtoday-mp3/102016-sassenrath.mp3">https://www.ksre.k-state.edu/news/radio-network/agtoday-mp3/102016-sassenrath.mp3</a>. Radio broadcast.  Smart, C. D. 2017. Cabbage Research and Development Fund Board Meeting, December 12, 2017 Geneva, NY. Susceptibility of Commercially Available Cabbage Varieties to the Black Rot Pathogen, second season. 30 minute talk to 18 growers and educators. Contact hours = 9.  Smart, C. D. 2017. Crop Consultant Meeting, November 30, 2017 Syracuse NY. Understanding and controlling diseases of tomato. 1 hour talk to 25 crop consultants. Contact hours = 25  Smart, C. D. 2017. Elementary classes visit Station. May 30-31, 2017. Eight classes visited Cornell’s NY State Ag Experiment Station for tours, and to see plants in the greenhouse. Each class was given a 30 minute explanation on disease and insect pests of crops, and a 30 minute tour of the greenhouses – total of 50 min per class. About 20 students per session. Contact hours = 160.  Smart, C. D. 2017. Elementary School Garden Planting. June 6-8, 2017. Work with each of eight classes to plant a section of the elementary school garden. 30 minutes per class, about 20 students per class (8 classes). Contact hours = 80  Smart, C. D. 2017. Empire State Producers Expo. January 18, 2017, Syracuse NY. Tomato bacterial diseases of 2016. 20 minute talk to 100 growers and educators. Contact hours = 33.  Smart, C. D. 2017. Empire State Producers Expo. January 18, 2017, Syracuse NY. Managing tomato leaf mold in high tunnel production. 20 minute talk to 90 growers and educators. Contact hours = 30.  Smart, C. D. 2017. Geneva City School District Summer Science Camp. July 01 – Aug 10, 2017. 20 x 3 hour sessions on science and agriculture with 16 third-grade students. Contact hours = 960.  Smart, C. D. 2017. Geneva Green Thumb Planting Event. April 20, 2017, Geneva NY. 2 hour workshop discussing seed planting and helping participants plant seed for their community or home gardens. About 20 participants. Contact hours = 40.  Smart, C. D. 2017. Geneva School District Third-Grade Seed Planting May 1-9, 2017. What are seeds and what makes them grow? Nine, 45 minute interactive sessions with students talking about seeds and planting vegetable seed. About 20 students per session, 9 sessions. Contact hours = 135. Conducted by Smart lab members Holly Lange, Valpuri Sovero and grad student Libby Cieniewicz.  Smart, C. D. 2017. Webinar for beginning vegetable growers entitled ‘Vegetable Diseases’, March 15, 2017. This was a 1 hour webinar to about 25 participants. Contact hours = 25

Impact Statements

Increased understanding of pathogen effectors