Brief Summary of Minutes of Annual Meeting

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.

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

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.