Spotted Wilt Virus Impacting Tomatoes Again

Virus has Gotten Past Resistant Gene

By Patrick Cavanaugh, Editor

Tomato spotted wilt virus is becoming big in the central San Joaquin Valley, according to Tom Turini, University of California Cooperative Extension Farm Advisor in Fresno County for vegetable crops. The virus had earlier been spotted in lettuce, and this has caused some concern in this season’s tomato crop.

Tom Turini

“We had some concerns early in the season that we might be looking at a year where it’ll become a challenge, because we were finding it in lettuce back in February and March in the Huron area,” Turini said. “And then we notice that tomatoes were showing the virus symptoms. We had been managing tomato spotted wilt in processing and fresh market tomatoes largely with a resistance gene, and it seemed that the resistance was breaking.”

The virus is spread by thrips, and the gene in the tomato was the biggest deterrent in combating thrips.

“We were also talking about an IPM program, but the industry was leaning on this gene. This gene became a big part of their spotted wilt prevention program,” Turini said. “While sanitation of weeds was practiced, and there was some thrips management, it was really dependent upon this single gene resistance in the tomatoes, and as of 2016, we saw evidence that that gene was no longer performing.”

Because the virus can wipe out entire tomato fields, researchers are scrambling to find a new way to deter the thrip spreading the virus on tomatoes.

New UC IPM Program Director

Jim Farrar Named Director of UC Statewide IPM Management Program

By Pam Kan-Rice, UCANR Assistant Director, News and Information Outreach

Jim Farrar has been named director of the Statewide Integrated Pest Management Program for the University of California’s Division of Agriculture and Natural Resources. He will begin as new uc ipm program director on Oct. 1.

UC IPM works with growers and residents to protect human health and the environment by reducing risks caused by pests and pest management practices.

Farrar is currently director of the Western IPM Center, where he has served since 2013. He succeeds Kassim Al-Khatib, UC IPM director since 2009, who is transitioning to a UC Cooperative Extension specialist position located in the Department of Plant Sciences at UC Davis. There Al-Khatib will focus on his research in weed management.

“UC IPM is a widely recognized national leader in integrated pest management,” Farrar said. “I am excited to continue efforts to make IPM the standard practice for managing pests in agriculture, communities and natural areas in California.”

Prior to joining the Western IPM Center, Farrar was a professor of plant pathology in the Department of Plant Science at California State University, Fresno for 12 years.

At Fresno State, Farrar received three teaching awards. He taught courses in plant pathology, plant nematology, diagnosis and control of plant diseases, crop improvement, aspects of crop productivity, mycology, sustainable agriculture and advanced pest management. His research centered on fungal diseases of vegetable crops, including management strategies for cavity spot of carrot. During his Fresno State tenure, he served four years as chair of the Department of Plant Science and a year as interim chair of the Department of Food Science and Nutrition.

From 1995 to 1997, Farrar taught in the Botany Department at Weber State University in Ogden, Utah. At Weber State, he conducted research on rock cress plants infected with a rust fungus that causes false-flowers. This rust is closely related to a species that is a potential biological control agent for dyer’s woad (Isatis tinctoris), an invasive weed.

Farrar has published scientific papers, extension newsletter articles, and articles in agricultural industry magazines. He also wrote a chapter in the book Tomato Health Management and five disease descriptions in the book Compendium of Umbelliferous Crop Diseases. He recently completed a three-year term as senior editor for feature articles in the journal Plant Disease and was senior editor for the online journal Plant Health Progress for three years. Farrar is a member of the American Phytopathological Society and the Pacific Division of the American Phytopathological Society.

The Wisconsin native completed his Ph.D. in botany and B.S. in plant pathology at the University of Wisconsin, Madison, and his M.S. in plant pathology at UC Davis.