Brief Summary of Minutes of Annual Meeting

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.”

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 F_ST = 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- Vegelys^TM, 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 20-25^oC, while R. oryzae had optimal growth at 30^oC.  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.

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. http://pnwhandbooks.org/plantdisease/pathogen-articles/pathogens-common-many-plants/bacteria-and-other-prokaryotes/management-cyanobacter

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.    6^th 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. 47^th 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, 54^th 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: http://skagit.granicus.com/MediaPlayer.php?view_id=8&clip_id=2036)

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 38^th Argentine Horticultural Congress, 16^th National Floricultural Conf., 8^th Scientific Meeting on Onion from MERCOSUR, and 3^rd 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. 8^th 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. 8^th 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)

http://css.wsu.edu/biofuels/presentations/2015pnw-oilseed-direct-seed-conference/powerpoint-presentations/

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. 9^th 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 21^st Century and beyond. A symposium at the 70^th 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 21^st 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. 47^th 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 47^th 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 1^st 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. 29^th 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 47^th 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 47^th 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 47^th 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. 18^th 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. 6^th 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 6^th 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. https://media.oregonstate.edu/media/t/0_7kh2o95w

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.” 30^th 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 1^st 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 1^st 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. https://ucd.adobeconnect.com/_a841422360/p4o2997j55g/?launcher=false&fcsContent=true&pbMode=normal

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