Researchers recommend potato growers in the Pacific Northwest intensify their field scouting programs for the potato psyllids that spread the crop disease zebra chip. Though no psyllids have yet been found in Idaho fields, the insects have surfaced on greenhouse-grown plants in garden centers in Twin Falls and Boise, according to an update posted by the Treasure Valley and Pacific Northwest Pest Alert Network.
A single potato psyllid was found in one field in Irrigon, Ore., on June 11, and another field in Hermiston, Ore., on June 13.
No psyllids have yet been found that are positive for the Liberibacter bacterium that causes zebra chip, which leaves bands in tuber flesh that darken when fried and reduces yields.