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Dr. du Toit interviewed for APS podcast series

Dr. Lindsey du Toit

Lindsey du Toit, Vegetable Seed Pathologist, was interviewed for the APS Plantopia podcast episode Seeds! which addresses the important role of seeds in our lives, what it takes to produce seed, and the impact of seed pathology on agriculture. Inspired by the United Nations declaration of 2020 as the International Year of Plant Health, the American Phytopathological Society created the podcast series Plantopia ( where plant pathologists explain how protecting plant health can protect plants and our food supply to ensure a sustainable future.

Lisa DeVetter wins ISHS Young Minds Award

Lisa DeVetter won the ISHS Young Minds Award for the best oral presentation at XII International Rubus and Ribes Symposium: Innovative Rubus and Ribes Production for High Quality Berries in Changing Environments in Switzerland in June 2019.

Woman crouches next to row of raspberry canes.Biodegradable and non-degradable plastic mulches increase raspberry yield. Growers and scientists alike within the field of horticulture are continually seeking ways to improve sustainable production of food crops. The application of plastic mulches is one way to enhance crop production through improved weed management and modification of soil temperature and moisture. However, the use of plastics in society is under scrutiny and end-of-life management of agricultural plastics is a growing concern that threatens sustainability. Biodegradable plastics are an alternative to non-degradable polyethylene and polypropylene plastic mulches. This research evaluated the application of biodegradable plastic mulches in floricane red raspberry in the Pacific Northwest (PNW). This two-year research project showed that biodegradable plastic mulches are comparable to non-degradable plastic mulches in a spring-planted ‘WakeTMField’ raspberry field. Furthermore, both biodegradable and non-degradable mulches increased yield by 34% and improved weed management compared to the non-mulched control, which represented growers’ standard practice. While raspberry growers in the PNW adopting mulch application as a tool to aid establishment of spring-planted raspberry, time will tell whether biodegradable mulches truly degrade according to US (ASTM D5988-18) and European standards (EN 17033). Regardless, this research highlights the application and potential of plasticulture for raspberry and other perennial fruit crops.

du Toit hosts scientist from Denmark

Drs. Merete Halkjaer Olesen (right) and Lindsey du Toit (left)
Merete Halkjaer Olesen (left) with Lindsey du Toit.

Dr. Merete Halkjaer Olesen, plant pathologist at Aarhus University in Flakkebjerg, Denmark, visited Dr. Lindsey du Toit’s vegetable seed pathology program at the WSU Mount Vernon NWREC from 20-23 July 2015 to work on diseases in spinach, table beet, and Swiss chard seed crops in northwestern Washington. Merete’s research has focused on diseases in spinach seed production in Denmark, where ~15,000 acres of spinach seed crops are grown annually. hire software developers

Western SARE Graduate Student Proposal Award

Shannon Carmody stands in a field of turnip seed.
Shannon standing in a turnip seed crop in the Willamette Valley of Oregon that was infected with black leg, light leaf spot, and white leaf spot.

Congratulations to Shannon Carmody, MS student in Dr. Lindsey du Toit’s vegetable seed pathology program, on applying successfully for a Western SARE Graduate Student Proposal Award. Her proposal was titled “Seed Transmission and Management of White Leaf Spot and Light Leaf Spot Pathogens in Brassicas in the Pacific Northwest”. The funding ($15,675) will help cover expenses for her thesis project. Shannon’s thesis committee includes Dr. Lindsey du Toit (chair), Dr. Lori Carris (WSU), Dr. Tim Paulitz (USDA ARS), and Dr. Cindy Ocamb (Oregon State University). Auskarai, dėžutės, pakabukai, vyriškos ir moteriškos grandinėlės, apyrankės ir sidabriniai žiedai su akmenimis

Annual Field Day highlights WSU Mount Vernon research programs, projects

Lisa DeVetter crouches by a blueberry bush.
Lisa Wasko DeVetter crouches near young blueberry bushes.
WSU Mount Vernon Small Fruit Horticulture Professor Lisa Wasko DeVetter inspects her program’s newly planted blueberry test plot. (Photo by Kim Binczewski)

Pollination, plant pathogens, and pesticide alternatives are a recurring theme in the 2015 WSU Mount Vernon NWREC Annual Field Day, which includes a lengthy walking field tour, research project updates, and an agricultural community barbecue here July 9.

The Annual Field Day, which began in the 1940s, is free and open to the public. It starts at 3:30 p.m. with a walking field tour of some of the nearly 150 acres of the Center’s active research plots. A tractor-driven wagon ride will service non-walkers, and Spanish language translation services will available throughout the tour from Kate Selting, Latino Farmer Outreach Educator with the WSU Small Farms Program/Skagit County Extension.

Field day group walks through a field of barley.
Visitors walk past an Alba winter barley test plot at the Research Center during last year’s WSU Mount Vernon Field Day. (Photo by Kim Binczewski)

Faculty members and graduate students representing the Center’s current Research and Extension programs will talk about their projects and how their work impacts the region’s growers, consumers, agricultural businesses and local economies.

“This annual event is a great opportunity to share with the community some highlights of what we do to help the region,” said WSU Mount Vernon Research Center Interim Director Debbie Inglis. “It is also a way we show our appreciation to the many people and groups, such as the Port of Skagit County, the Northwest Agricultural Research Foundation, and all the growers and industry representatives who fuel our research and contribute to our mission.”

WSU Mount Vernon’s mission is to serve the agricultural, horticultural, and natural resource science interests of the state through research and extension activities that are enhanced by the unique conditions of northwestern Washington: its mild, marine climate, rich alluvial soils, diverse small and mid-sized farming enterprises, and unique rural-urban interface.

This year’s Field Day presentations highlight all of the Center’s research programs: plant breeding, small fruit horticulture, berry pathology, entomology, vegetable seed pathology, vegetable horticulture, vegetable pathology, weed science, and dairy/livestock.

Three of the represented research programs are working on projects to help growers productively respond to issues involving pollination, plant pathogens, and pesticide alternatives.

Included among the presenters are Small Fruit Horticulture Program Leader Lisa Wasko DeVetter and her Ph.D students, Rachel Rudolph and Matt Arrington, who are respectively studying new options to promote the sustainable production of raspberries and blueberries.

“Rachel and I are investigating alternative pre-plant treatments for soil-borne disease/pest management in continuous red raspberry systems that may be suitable alternatives to chemical soil fumigation,” DeVetter said. “Rachel is also looking at several species of cover crops that may be able to suppress soil-borne disease and pests while promoting soil quality.”

Arrington’s research project involves enhancing pollination and fruit set in blueberry.

“Matt has been building on some of my earlier work to understand factors that limit fruit set and yield of blueberry in western Washington,” said DeVetter. “We have confirmed that visitation rates of honeybee (Apis mellifera) is very low in western Washington, which is likely due to unfavorable weather conditions. We have also observed that visitation rates are greater in organic fields.

“My program is developing recommendations on ways to promote and optimize honeybee activity and overall pollination for blueberry,” she added.

The Vegetable Seed Pathology team will provide updates on its ongoing research, including the impacts of bacterial pathogens in table beet and Swiss chard seed crops and fungal pathogens of plants in the cabbage family, according to program leader Lindsey du Toit. Our team of experts has selected the best fishing reels out of hundreds of models. Don’t buy a fishing reel before reading these reviews. We purchase every product we review with our own funds — we never accept anything from product manufacturers. Here are the best fishing rods and reels If you have a decent amount of fishing experience, a baitcasting reel can be extremely effective for catching these fish with minimal effort.

M.S.students Shannon Carmody and John Weber will provide information about their respective work with brassica species and sunflower seed production.

“Shannon’s research project involves evaluating how readily certain fungi that infect brassica plants can be seed transmitted in brassica species and whether seed treatments (organic and conventional fungicides) being used by growers and seed companies around the world will help prevent seed transmission of these fungi,” said du Toit.

Field day group listens to a presentation in a potato field.
Yukon Nugget potato plants are in full flower for the 2014 Field Day presentations at WSU Mount Vernon. (Photo by Kim Binczewski)

“John will discuss his project working with sunflower seed growers to improve their management practices for white mold, caused by the fungus Sclerotinia sclerotiorum, which has emerged as the main disease affecting the burgeoning sunflower seed production industry in Washington,” she said.

Weeds impact all crops, and Weed Science Program Leader Tim Miller and his Ph.D student, Yushan “Sherry” Duan, will be on hand to discuss some results of that program’s new product testing and research which has yielded new techniques for weed management.

“I’ll be discussing weed control – including in three types of crops: seeds crops, berries, and ornamentals,” Miller said. “Seed crops include the vegetable crops (primarily table beets, spinach, and cabbage) that are grown in northwest Washington and a new potential crop (quinoa) for the state.

“I’ll be testing various herbicide combinations on first-year berries and will have some plots with ‘living mulch’ plants growing under newly planted blueberry,” he added. “I’ll also be looking at various ornamental crops, including tulip, daffodil, iris, gladiola, caladium, peony, and dahlia. “Sherry will talk about her current research involving cover crops in tulip production.”

The Center’s Annual Field Day will wind down at approximately 6 p.m. with a barbecue on the grounds near the Center’s Tree House meeting space, where visitors can enjoy a locally prepared meal and connect with others in the agricultural community. More information about this year’s event is available from Field Day Coordinator Susan Kerr, 360-848-6151, . Links to specific program research are available on the WSU Mount Vernon website,

WSU Mount Vernon Small Grains Field Day heralds new grain varieties, flavors

Steve Lyon - winter wheat photo
Plant breeder Steve Lyon checks out some hard red winter wheat from an early generation breeding line at the WSU Mount Vernon Research Center. (Photo by Kim Binczewski)

Flavor in many forms will be featured at this year’s Small Grains Field Day here at the Research Center from 3 to 6 p.m. June 25, 2015.

The annual event, which is free and open to the public, gives the community of growers, industry representatives, and consumers a chance to network and learn about the latest small-grains research and how it impacts the economy in the Skagit Valley and beyond.

Small grains include wheat, barley, oats, and the pseudo-cereal grain buckwheat. This year’s Field Day highlights examples of the latest varieties specifically bred for and adapted to the mild marine climate of the Pacific Northwest, according to Steve Lyon, senior scientific assistant for the WSU Mount Vernon plant breeding program.

“Right now we’re looking at some really nice lines – like ‘Edison,’ a hard white spring wheat selected from long-time Bellingham plant breeder Merrill Lewis’ Fossum Remnants seed plantings,” said Lyon. “And ‘Richard,’ a new spring barley recently released by Washington State University specifically for western Washington, is already earning rave reviews from craft maltsters.”

There will be plenty of locally growing plants and harvested seed examples to see which reflect the range of color, flavor and aroma that some of these local grains bring to the table, Lyon said. “Much of the research we’ve been doing here at the Center reflects a renewed interest from breeders, growers and consumers in heritage grains and regional wheats that can add distinct flavor, character, and nutritional value when incorporated into whole-wheat products.”

Alba barley field photo 2
Visitors walk past a field of Alba barley during their tour of the research fields during the 2014 Small Grains Field Day. (Photo by Kim Binczewski)

For organizers and attendees alike, Small Grains Field Day provides something for the whole community.

“Whether we’re developing seed for farmers, amassing knowledge among researchers, or opening new niche markets for millers, bakers and maltsters, we are working together to build sustainable, high-quality, high-yield, disease-resistant small grains production in the Northwest,” said Lyon.

“One focus with small grains has been to bring in established varieties new to this area to see how they perform in our environment,” he added. “If a variety is going to fail, we want it to happen in our variety testing trials rather than in a farmer’s field, where it would cost them money.”

This marks the fifth year WSU Mount Vernon researchers have been breeding winter wheat for this region.

“Several wheat varieties already earning praise for their flavor have been bred, selected, produced and milled in the Skagit Valley,” Lyon said. “And there are even more promising varieties with the potential to grow well and be successfully utilized here on the west side of the Cascade Mountains.

“What is unique about these lines is that before one is released to the public, it will not only excel agronomically but must make a high-quality, flavorful end product,” he added.

There are also some promising hard red and soft white winter wheats from private European companies, and some spring varieties through CIMMYT “which do well in high rainfall areas and are especially good for bread wheat,” Lyon said.

CIMMYT is the Spanish acronym for the International Maize and Wheat Improvement Center, a non-profit organization based in Mexico that researches sustainable development of wheat and maize farming worldwide. It provides seed, agronomy and agriculture research products, services and related tools to farmers in developing countries and maintains a seed bank which makes seed freely available to researchers.

At WSU Mount Vernon, plant breeding researchers grow and test the seed to determine suitable grains for this climate. In The Bread Lab, testing is taken to the next level to determine the qualities of local small grains that make them desirable for milling, baking and malting.

“We now have five years’ worth of local agronomic data posted to our website, so anyone can decide which varieties might work best for them,” Lyon said. “A new variety has to be profitable for the farmer yet — in its final form — be something the public will want to consume.”

More information about Small Grains Field Day and the WSU Mount Vernon Plant Breeding Program and Bread Lab is available at

Smick Scholarship Award

Shannon Carmody stands in a field of turnip seed.
Carol Miles
Shannon Carmody in a turnip seed crop field, Willamette Valley, OR” (photo by Lindsey du Toit)

Congratulations to Shannon Carmody, MS student in the Vegetable Seed Pathology program, on receiving the Alexander A. Smick Scholarship in Rural Community Service and Development. Shannon will receive $2,000 to develop a “Plant Pathology 101” workshop this fall in Mount Vernon, WA under the direction of Dr. Lindsey du Toit with the WSU Vegetable Seed Pathology Program, and a local non-profit, Viva Farms, to provide outreach to Spanish-speaking farmers in the Skagit Valley. The curriculum for this workshop will be designed by Shannon to help beginning farmers answer the question “What’s wrong with my plants?” The workshop will deliver basic information on plant pests, diseases, and nutritional problems, using simultaneous Spanish-English services. Shannon will develop a set of diagnostic questions to help farmers try to understand the problems they see happening in their fields. The workshop will introduce agriculture resources available through the WSU Mount Vernon Northwestern Washington Research and Extension Center (entomology, weed science, horticulture, and plant pathology programs that provide extension and outreach), as well as the WSU Master Gardener program, and the Plant & Insect Diagnostic Lab at the WSU Puyallup REC. Shannon hopes that these funds can be used to develop a relevant and replicable workshop that could be used by others working with similar farming communities in the Pacific Northwest. She is excited to be a part of the Alexander A. and Agnes “Odegaard” Smick Scholarship program because she cannot imagine anything more important than providing tools and resources for the people who grow our food. click here

Shannon enrolled as a graduate student at WSU in January 2015, after working in organic seed and agriculture for six years. Most recently, Shannon was the Operations Director for Viva Farms, a land-based farm business incubator in the Skagit Valley of northwestern Washington that helps beginning farmers and farm workers transition to farm ownership. Prior to that, Shannon worked for 5 years as the Public Programs Director at Seed Savers Exchange in Iowa, one of the largest non-governmental seed banks in North America. At Seed Savers, she was surrounded by an abundant diversity of vegetable seed, ~70 crop types, representing the cumulative work of many agriculturalists. It is at the intersection of seed and the people who grow them that Shannon decided to pursue the study of vegetable seed pathology at Washington State University. Shannon grew up in Rock Island, Illinois, and graduated with a double major in Environmental Studies and International Relations from Beloit College in Beloit, WI.

Research explores cover crop role in reducing tulip-bulb weeds, diseases

Carol Miles
Ph.D. student Yushan “Sherry” Duan (pictured here with emerging tulips from a WSU Mount Vernon greenhouse trial) is completing a study this year on how cover crops impact weed development and bulb diseases in tulip plantings. (Photo by Kim Binczewski)

As WSU weed scientist Tim Miller puts it, tulips “go hand in hand with weeds” this time of year in the Skagit Valley, where the annual Tulip Festival during the month of April attracts hundreds of thousands of visitors from around the world to this small farming community approximately one hour’s drive north of Seattle.

Yet weeds are only half the battle for the commercial and small-scale growers here who hope to reap a share of the profits from the state’s $12-million-per-year ornamental bulb industry during the short growing and harvest season for specialty cut-flower and bulb crops.

The rest of the fight is underground, where soil-borne diseases like tulip fire (caused by the fungus Botrytis tulipae) and tulip-gray bulb rot (caused by the fungus Rhizoctonia tuliparum) can spread through the soil and infect the bulbs of their host plants, resulting in significant losses in flowers and bulb yield.

Promising tool for growers

Northwest growers may someday have an added weapon in their agricultural arsenal against tulip bulb weeds and diseases, as a result of cover crop research being conducted by Miller’s WSU Mount Vernon weed science research team, led byPh.D. student Yushan “Sherry” Duan.

Duan was enlisted in 2012 to study the impacts of plow-down and cover crops on field production of tulip — one of 25 research projects funded under the Farm Bill through Washington State Department of Agriculture Specialty Crop Block Grants totaling $3 million.

“Ornamental bulb farmers are limited to fumigation and a small assortment of highly regulated fungicides and pesticides, which can be costly to their bottom line if multiple applications are needed each year,” said Duan. “For the small-scale growers, fumigation is not an option due to restrictions on many of the chemicals that were previously available for agricultural purposes.”

“Our research has been twofold,” Miller said. “First, we wanted to see whether cover crops or green manure plow-down crops can reduce competition from weeds and soil-borne pathogens, and perhaps reduce the need for pesticide applications. Second, we wanted to find out whether growing these crops immediately before tulips negatively affects flower or bulb production by creating field conditions that are unfavorable for tulip.”

Cut-flower tulip grower Roger Knutson helped Duan establish her half-acre plots on his land near Sumner, Washington, where she planted two cover crops – a wheat-and-pea mixture, and a two-variety blend of mustard. Cover crops were planted in mid-summer, grown for four weeks, then plowed into the soil about a month prior to planting tulip bulbs. “We planted the cover crops, and he planted the tulips,” Duan said. “It was a real team effort.”

Potential for crop rotation

In the experiments on Knutson’s farm, half the cover crops were killed with glyphosate, a systemic herbicide, prior to incorporating them into the soil. The other half were not treated.

A concern regarding cover crops is that they can persist as weeds in the following crop, leaving what the researchers refer to as a “trashy seedbed” prior to bulb planting.  “After the first year, we switched to a cereal rye-pea mix, because we found the winter wheat we planted in late summer was quite weedy in the tulip crop the following spring,” Duan said.

In this third year of Duan’s research, results have been surprising and encouraging.

“On the one hand, we didn’t see much difference in bulb yield or flower quality with any of the cover crops on the commercial grower’s field, which are treated with herbicides and fungicides and so do not incur much weed or disease pressure,” Duan said.  “On the other hand, these cover crops didn’t hurt bulb yield or flower quality, so it appears they should fit nicely into a tulip rotation.”

Pre-empting disease

Miller and Duan are also conducting companion trials in tulip at the WSU Mount Vernon research station.  In a controlled experiment, Duan is infesting soil with the fungi that cause tulip fire and tulip-gray bulb rot prior to planting cover crops to determine if the cover crops can help reduce the incidence of these diseases in the tulip crop.  She is working closely with WSU Puyallup Plant Pathologist Gary Chastagner.

“We planted cover crops either in July or in August to see how planting date affects cover crop growth or their ability to control soil-borne diseases,” said Duan.  “We are also evaluating how quickly cover crops break down in the soil before planting tulip. Cover crop residue left on the soil surface should help reduce weed seed germination in the tulip crop.”

In the first round of testing, the level of tulip fire was cut by growing a rye-pea mix in August before planting tulip bulbs in October. If second-year results are similar, Duan may have identified a strategy producers can use to reduce the risk of tulip fire in field-grown tulips.

“It is encouraging that we are seeing a reduction in Botrytis in the rye-pea cover crop, because tulip fire is host-specific to tulips,” Duan said. “The break cover crops provide may be enough to get rid of the disease in the soil. If we can manage this disease with cover crops, then tulip growers could potentially continue to plant the same crop each year — and not have to alternate between tulips and daffodils.”

Unexpected results

Both researchers thought they would see a reduction in the fungi which cause tulip fire and tulip-gray bulb rot in the soil plots into which mustard cover crops were tilled prior to tulip planting, because of mustard’s ability to suppress soil-borne diseases.

“We expected the mustard to eliminate soil-borne diseases, but we haven’t seen that in our trials,” Duan said. “We’re still waiting on soil-test results regarding soil microbial activity, so the jury’s still out as to why that might be the case.”

This June marks Duan’s final harvest season with this cover crop project, as she expects to complete her dissertation with three years’ of field data, two years’ of station research, and several greenhouse trials.

We hope to gain good information on how effective cover crops will be in potentially reducing weed and disease pressure in our Pacific Northwest tulip crops,” Miller said.  “Ultimately, the knowledge gained may lead to reductions in the quantity of herbicides and fungicides that are needed to produce the high-quality cut flowers and bulbs for which the region is famous.”

Impacts on fruit quality focus of new WSU biodegradable mulch research

Lisa Wasko DeVetter leads a team of WSU researchers who will spend the next two years studying the impacts of biodegradable mulches on sustainability and fruit quality. (Photo by Kim Binczewski)

The development of biodegradable mulches has provided some potential eco-friendly benefits to the agriculture industry, but until now there has been no way to determine how these new weed-controlling, moisture-preserving products affect fruit quality.

WSU Mount Vernon Small Fruit Horticulture Program Leader Lisa Wasko DeVetteris about to bridge that information gap as the lead scientist on a newly funded research project.

Thanks to a two-year, $40,000 grant from the university’s College of Agricultural, Human, and Natural Resource Sciences, DeVetter and two WSU colleagues will study how chemical constituents from deteriorating biodegradable mulches migrate to developing fruits. The grant is one of WSU’s eight “Emerging Research Issues” projects designed to utilize innovative approaches to resolve significant issues – including social and economic factors — faced by the state’s agricultural industries.

“The WSU Mount Vernon Research Center has a great history of conducting research with biodegradable mulches (BDMs) in horticultural crop production, much to the credit of the initial work done by our vegetable horticulturist, Dr. Carol Miles, and our vegetable pathologist, Dr. Debra Inglis,” said DeVetter. “But there has been no evaluation of how these products impact fruit quality.”

According to DeVetter, who has been working closely with small fruit growers and researchers in this community for nearly a year now, this project was prompted by some unanswered questions about biodegradable mulch products.

“Specifically, there has been no research examining the potential for chemical constituents in these mulches to move into food crops physically in contact with BDMs during a growing season,” DeVetter said. “Additional questions remain about the application of these products in organic agriculture, which needs critical review. This research is intended to fill in some of the gaps in our knowledge.”

Helping fill those gaps are DeVetter’s fellow researchers on this project: Miles, a professor in the WSU Department of Horticulture; and Shyam Sablani, an associate professor with WSU’s Biological Systems Engineering.

“Dr. Miles will assist with the evaluation of BDM treatments, while Dr. Sablani will assist in measuring chemical migration in strawberry fruits, which we are using as a mode crop for this experiment,” said DeVetter. “A master’s student will complete this project as part of his/her thesis research and will be advised by both Drs. Miles and Sablani.”

The research team’s ultimate goal is to help give growers and producers some more sustainable, environmentally friendly options.

“Biodegradable mulches have potential as a more sustainable method of crop production relative to traditional plasticulture, which is dependent on polymer-based plastics that have significant disposal challenges,” DeVetter said. “We would like to help growers and mulch manufacturers gain confidence, validated through research, that growing crops with BDMs allows for the production of a delicious and safe product for consumers.”

Soil samples show the differences when the same spinach lines are planted in a high-risk field (left), medium-risk field (center) and low-risk field (right). (Photos courtesy of Lindsey du Toit)
Soil that has been shredded and is ready for potting.  (Photo by Kim Binczewski)