a tiny homopterous insect, Paratrioza cockerelli, occurring in some areas of the western U.S., western Canada, and Mexico: a serious pest to potatoes, tomatoes, eggplants, and peppers, the nymphs acting as vectors in the transmission of psyllid yellows.
a viral disease transmitted by the potato psyllid, causing the young leaves of potatoes, tomatoes, eggplants, and peppers to curl and turn yellow or purplish.
