US (WA): Potato psyllid found in 79% of field samples

Last week, Washington State University Extension researchers found the potato psyllid insect on 79 percent of field samples throughout the Lower Columbia Basin, up from 60 percent the week before and 50 percent the week before that. Each sample contained an average of 3.1 psyllids, up from 0.6 the week before.

The psyllids, which feed on potato leaves, “are a big deal because they can transmit a bacterium to potatoes that causes zebra chip disease,” said Carrie Wohleb, a WSU professor and regional vegetable specialist in Moses Lake.

She and her colleagues are testing the psyllids they collect for the zebra chip bacterium. So far, fewer than 1 percent of the bugs tested this year have been carriers of the disease.

Zebra chip causes symptoms similar to other diseases and so is difficult to diagnose.

She recommends that farmers use insecticides to help control the pests.

The psyllid is just one of the insects Wohleb and others in a statewide potato insect monitoring network observe. The potato growers of Washington, through a grant from the Washington State Potato Commission, fund the network.

For more information:
Carrie Wohleb
WSU
Tel: +1 509-754-2011 ext. 4313
Email: cwohleb@wsu.edu