IPM for Powdery Mildew, Phylloxera, Spotted Lanternfly and More
Extension Viticulturist Michelle Moyer recorded the video A Pre-Season Checklist for Powdery Mildew Management that will soon be posted on the Vineyard Team website. This video and others are made available free of charge and on-demand at the Vineyard Team Sustainable Winegrowing Education page.
Moyer has been reviewing certification standards as part of the Technical Group for the Sustainable WA program, which supports environmentally sound, socially equitable, and economically viable wine growing in Washington State.
The Washington State Grape Society held its annual meeting and trade show in November. PhD student Bernadette Gagnier spoke about Screening Rootstocks Against the Northern Root-Knot Nematode. Several other Moyer team members presented posters on topics including their long-term rootstock field trial, a grower-collaborator rootstock trial with Inland Desert Nursery, and the WSDA Grape Quarantines / Quarantine Pest Management Plans.
In December, Moyer co-hosted a WAVEx webinar: Spotted Lanternfly Update, along with the Washington State Wine Commission. Michela Centinari from Penn State described the impacts of this pest on grapes in the east coast and the management tactics that have been working in that region.
Many grape growers have reached out to Moyer’s team for help and advice about rootstocks and phylloxera. The Phylloxera Management Resources web page is a great place to start!
Highlighting the Role of Biocontrol in SWD
Tree Fruit IPM Extension Specialist Betsy Beers’ ongoing work on spotted-wing drosophila (SWD) management includes a recent focus on the Figitidae family of parasitoid wasps, specifically Ganaspis brasiliensis and Leptopilina japonica. Graduate student Robert Czokajlo has been working on sampling these beneficial wasps. Beers presented a summary of this work to an international audience at the North American Spotted Wing Drosophila Biocontrol Working Group online meeting in November. An article by Czokajlo and Beers, Comparison of Sampling Methods for Figitidae Attacking Drosophila suzukii, recaps the study on the WSU Tree Fruit Entomology website.
Aspects of Beers’ and Czokajlo’s work were also presented by USDA-ARS colleague Xingeng Wang at the Advances in Biological Control for Management of Spotted-Wing Drosophila webinar in December. Over 300 viewers registered for the webinar, a joint project of the multi-state Sustainable SWD Management Team. Xingeng Wang’s presentation focused on a nationwide release of Ganaspis in 2022 and 2023 that was part of a multi-institutional study quantifying the presence and impacts of this larval parasitoid.
Beers, along with postdoctoral research assistant Dylan Beal and WSU Entomologist Tobin Northfield, also presented Coordinating SWD and X Disease Management to the Northwest Cherry and Stone Fruit Research Review in Yakima in November. This full-day event was jointly sponsored by the Washington Tree Fruit Research Commission and the Oregon Sweet Cherry Commission.
Tilth Conference Features IPM in a Changing Climate
Horticulture and IPM Specialist Laurel Moulton with the WSU Regional Small Farms Program coordinated the WSU Science Symposium at the Tilth Conference in October. The theme was IPM in a Changing Climate. The popular conference was held in Port Townsend and was sponsored by the Tilth Alliance.
The speaker session featured WSU’s Lindsey Du Toit and University of Idaho’s Sanford Eigenbrode. Plant Pathologist Du Toit addressed how disease pressure in agricultural crops is expected to change as our climate changes and offered tips on how farmers can adjust IPM practices to make their farm more resilient to disease pressure. Entomologist Eigenbrode, a leader in the changing climate impacts on the insect world, spoke about what a changing climate means for both pests and beneficial insects.
Moulton also spearheaded an IPM poster session at the conference. Contributors included the WSU Sustainable Seed Systems Lab (buckwheat), Thurston County WSU Extension Agriculture program (restoration grazing), WSU Department of Plant Pathology (wheat), WSU Department of Crop and Soil Sciences (quinoa), Oregon IPM Center’s Solve Pest Problems website, and South Whidbey Tilth (native pollinators). Moulton co-authored a presentation with Laura Schulz, Srijana Shrestha, and Carol Miles from the WSU Northwestern Washington Research and Extension Center on their recent work on wireworm resistant sweet potato cultivars.
Master Gardeners Increase Pollinator Knowledge via Webinar
Prior to her retirement in early 2023, Urban IPM Coordinator Carrie Foss, along with WSU Master Gardener Program Leader Jennifer Marquis and the team at WSU Social and Economic Sciences Research Center (SESRC), partnered to produce a set of surveys designed to measure the impact on knowledge and behavior resulting from a Master Gardener webinar on pollinator protection and habitat presented in March 2023. The post-training survey took place in October and November 2023.
- Before training, 30% of participants ranked themselves as “moderately knowledgeable” or “very knowledgeable;” post-training that increased to 66%.
- Nearly half (49.4%) of participants claimed “very little or no knowledge at all about PNW bee species” before training; after training 84% claimed some degree of “knowledgeable.”
- Since Master Gardeners perform an educational role in their communities, participants were asked about their confidence in communicating how to attract pollinators. Pre-training, 49.2% stated they were “not at all confident” or only “slightly confident”; post-training, 85.3% were “somewhat,” “moderately,” or “very” confident.
Participant comments included: “…very clear, focused and informative,” “…huge eye-opener for me,” “speakers and presentations were excellent,” “fantastic webinar!” “excellent resources,” “glad I attended,” “every Master Gardener should take this course!” and “Loved it! Please do it again!”
Breaking Down Barriers to Biodegradable Plastic Mulch Use
Vegetable Horticulture Specialist Carol Miles was the lead presenter at a workshop on Biodegradable Plastic Mulch for Crop Production in Honolulu in December 2024. The workshop, hosted by Amjad Ahmad at the University of Hawaii, was attended by 26 participants. Growers expressed a strong interest in using soil-biodegradable plastic mulch (BDM) but currently shipping costs from mainland U.S. are a barrier to access. Miles facilitated contact with the owner/operator of an Everett based company that ships fertilizer to Hawaii that is exploring feasibility and cost of BDM shipments.
Miles was co-author on a review article, Biodegradable Plastics as Alternatives for Polyethylene Mulch Films, that is in press with the journal Advances in Agronomy. Lead author Yingxue Yu (WSU), co-authors Margarita Valandia and Douglas Hayes (University of Tennesee), Lisa DeVetter and Markus Flury (WSU), and Miles summarize and critically synthesize current knowledge about BDM, including its history, biodegradability, use and lifecycle, agronomic performance, and environmental impacts.
Miles’ team revised the video How to Assess Mulch Deterioration As Percent Soil Exposure and uploaded it to the Media page of the Plastic Mulch website.
Sustainable Mulch Management (pdf) Fall/Winter 2023 edition was released. Interested readers can view past issues and subscribe on the Newsletter page of the website.
Honey Bee Team Has More Tools to Fight Varroa
Honey Bee Health Specialist Brandon Hopkins and his colleagues continue their outreach to the beekeeping community on ways to control the primary honey bee pest, Varroa destructor.
Hopkins’ team is looking forward to helping beekeepers incorporate VarroxSan, a new stabilized oxalic acid formulation, into their IPM toolkit. Recently approved by the U.S. Environmental Protection Agency, VarroxSan has high efficacy, low bee toxicity, and minimal residues. Its formulation is released at a slower rate (~56-day active period) than the oxalic acid formulation currently available, reducing the need for multiple reapplications and ensuring that the mites still developing inside brood cells at time of application are eliminated once they emerge. VarroxSan has a different mode of action than Amitraz, a commonly used acaricide to which Varroa have exhibited resistance development.
The bee program is getting closer to being able to promote entomopathogenic fungi for Varroa control. Large-scale research on the safety and efficacy of Metarhizium as biocontrol agent by Hopkins’ colleague, Saumik Basu, confirmed that the fungus is a more effective cause of death to Varroa than other stressors, and found that honey bee deaths decline when Metarhizium is present. Additionally, a company has signed an agreement to begin commercially producing Metarhizium.
Promoting Harvest Weed Seed Control as an IPM Tactic
Small Grains Extension Specialist Drew Lyon continues to educate growers on harvest weed seed control, speaking at the Washington State Crop Improvement Association in November and the Getting Rid of Weeds (GROW) through Integrated Weed Management Farmer Forum in December. Lyon also worked with Claudio Rubione of GROW to put together four videos of Washington wheat growers using impact mills on their combines to destroy weed seeds collected at harvest.
The first two infestations of Palmer amaranth were found in the state of Washington in 2023. Lyon spoke about this invasive weed at the Western Pulse Growers Association annual meeting in December.
The WSU Wheat Academy was held in December. Presentations relating to IPM included:
- Diagnosing and Managing Diseases of Wheat (pdf) by WSU’s Tim Murray and Cassandra Bates
- Biology and Management of Pests in Wheat, Canola, and Pulses by WSU’s Dale Whaley and University of Idaho’s Sanford Eigenbrode
- Managing Weeds with Less Reliance on Herbicides by WSU’s Ian Burke and Lyon
Lyon wrote a Weeders of the West blog post entitled Some Concerns with Roundup Ready Spring Canola for Italian Ryegrass Control and a posted a few IPM-related episodes on the WSU Wheat Beat Podcast. Several Timely Topics related to IPM, including the 2023 Plant Diagnostic Clinic Wrap-up, were published on the WSU Wheat & Small Grains website.
2023 Onion Cultivar Trial Results Now Available
Regional Vegetable Specialist Tim Waters and colleagues Carrie Wohleb and Lindsey du Toit announced the results of the 2023 WSU Columbia Basin Onion Cultivar Demonstration trials in a WSU Onion Alert e-newsletter on November 3.
This year’s Onion Cultivar Demonstration included 52 cultivars and lines from 7 different seed companies. It was planted in early April in a drip-irrigated field west of Moses Lake. The trial design was a randomized complete block with three replicate plots for each cultivar. We harvested the trial in mid-September. Each plot was evaluated for yield (usable and culls) and size distribution (shown as weight per category and % of total bulb count in the report. A subset of the harvested bulbs was placed in storage. In February, the team will evaluate the bulbs for firmness, scale retention, uniformity of shape, % single centers, and incidences of bacterial rot, neck rot, black mold, and internal defects such as double centers. These results will be shared in this WSU Extension IPM newsletter next quarter.
WSU’s Onion Cultivar Trial Archives includes demonstration and storage results dating back to 1999.
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