Two national research teams led by WSU scientists have received over $5.6 million in Specialty Crop Research Initiative grants from the U.S. Department of Agriculture’s National Institute of Food and Agriculture.

The researchers are working to protect valuable U.S. grape, onion and garlic crops from devastating and adaptive pests and diseases.

Hanu Pappu, a professor in the department of plant pathology, received $3.29 million to understand and stop pests and diseases harming onions and garlic through sustainable defenses.

Michelle Moyer, viticulture and enology associate professor, received an initial $2.4 million to study and tackle fungicide resistance threatening wine, table grape and raisin crops.

Pest and diseases

Pappu’s research team includes USDA’s Agricultural Research Service, New Mexico State University, Oregon State University, Cornell University, College of Idaho and University of California Agriculture and Natural Resources.

The team includes multidisciplinary research with plant pathologists, entomologists, breeders, economists, sociologists and food scientists. Pappu is joined at WSU by extension entomologist Tim Waters.

Washington state is ranked the third-highest grower of onions in the U.S., he said.

Pappu said the team is working to reduce the use of pesticides to control thrips, a tiny insect pest, which infest alliums, the genus which includes garlic and onions. They are also developing crop varieties that are resistant to the pest and the virus they carry, Iris yellow spot virus.

“In onions, this virus can cause lesions and death of tissues, which makes the plants weak and severely affects the crop yield,” Pappu said. “This can cause 100 percent loss of yield.”

Controlling thrips is a challenge because insect populations are in the millions and hard to stop, Pappu said.

“Thrips are like a free Uber ride for the virus that acts as a hitchhiker,” Pappu said.

Another challenge Pappu is working on is white rot, a disease of alliums that can survive in soil for up to 20 years and can cause large crop loss.

Pappu and his team are trying to find environmentally-friendly solutions that will limit the need for chemicals or sprays.

“Our growers need solutions from research to get answers to create control options,” Pappu said.

Fungicide resistance

Moyer’s team just launched a four-year, multiple institution project titled “Fungicide Resistance Assessment, Mitigation and Extension Network for Wine, Table and Raisin Grapes (FRAME).”

The team is looking at the fungal disease, powdery mildew and how the fast-adapting fungus is developing resistance to common control chemicals.

“When something that has worked in the past doesn’t work, we start to get nervous,” Moyer said.

The project is a partnership with Michigan State University, USDA-ARS, Ohio State University, University of Utah, University of California, Davis, University of Georgia and University of California Cooperative Extension.

Moyer said fungicide resistance is similar to antibiotic resistance in humans.

“Over the years, people have either overused products or misused it in the sense that the spray technique was not appropriate,” Moyer said.

Because of that misuse, growers are forced to use older chemicals that have a broader reach, meaning they must spray more frequently and could affect other organisms, she said.

Molecular biologists on the team will help create better, faster tests for monitoring resistance. Extension specialists will help with grower outreach by increasing awareness and help them make informed decisions.

Ana Espinola-Arredondo, economic sciences associate professor, is also part of the team. Her role on the project involves working with growers and chemical companies to use products correctly to avoid resistance.

Moyer said the goals of the project include improving how people monitor and detect fungicide resistance and using current control chemicals more effectively.