New UI Entomologist Has Zebra Chip Background

Published online: Nov 07, 2013 Insecticide, Potato Storage John O'Connell, Capital Press
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ABERDEEN, Idaho - Though Arash Rashed will emphasize cereal grains as the new entomologist with the University of Idaho's Aberdeen Research & Extension Center, he also brings expertise on a costly disease of special concern to the potato industry.

Zebra chip is spread by tiny, winged potato psyllids and ruins tubers with stripes that darken when fried. In 2011, about a year before zebra chip first surfaced in the Pacific Northwest, Rashed was studying it at the Texas A&M AgriLife Research and Extension Center in Amarillo, Texas.

Rashed, 37, started with UI in August, filling a position vacated almost three years ago by Juan Alvarez and left empty for budgetary reasons. UI Extension cereals pathologist Juliet Marshall has introduced him to local cereal growers. Alvarez has also met with potato farmers attending a retreat in Sun Valley, Idaho.

"(Because) I come from Texas, that's the first thing they ask me. `Do you know anything about zebra chip?'" Rashed said.

Donald Thill, director of the Idaho Agricultural Experiment Station, explained the position is integral in UI's efforts to research from the standpoint of a cropping system rather than an individual commodity.

"It is so key of a position for that area of southeast Idaho," Thill said. "The position has responsibilities not only for cereals but the crops grown in rotation with cereals, which certainly includes potatoes."

In Amarillo, Rashed discovered psyllid populations were supported by natural vegetation surrounding potato fields, including silver leaf nightshade, and the insects would move to potato fields shortly after emergence.

Rashed also studied the relationship between psyllid density and disease severity, and how tuber chemistry affects the pathogen. In 2012, about the same time as an Idaho entomologist discovered psyllids overwintering near Boise, Rashed was involved in research demonstrating psyllids could survive the harsh winters of the Texas Panhandle.

Rashed is currently collaborating with his former Texas supervisor, Charles Rush, UI Extension storage specialist Nora Olsen and others to determine how late infestations affect tubers in storage.

"We don't know whether the pathogen continues to multiply (in storage) or not," Rashed said.

He's also involved in long-term cereal projects delving into barley yellow dwarf virus, barley mealy bug, sawflies and wireworms. He explained wireworms have caused extensive damage in the region during the past few years and are extremely difficult to control.

"Apparently some of the chemicals being used have not been as effective as they thought they would be," said Rashed, who intends to collaborate with scientists in Oregon, Washington and Montana.

He said few scientists are studying wireworms because it takes years for their larvae to mature. He plans to solicit advice from colleagues regarding sawflies-a growing problem in eastern Idaho wheat-during the upcoming Entomological Society of America annual meeting.

Rashed was born in Lincoln, Neb., and raised in Iran, where he obtained his bachelor's and master's degrees in plant protection and entomology. He obtained his Ph.D. in insect evolutionary ecology in Canada.

Jeff Stark, superintendent at the Aberdeen facility, said an entomologist is essential for his operation.

"One of the greatest problems we are facing right now as a general category are insect-transmitted diseases," Stark said.