Potato Psyllid

Bactericera cockerelli, also known as the potato psyllid, is a species of psyllid native to southern North America. Its range extends from Central America north to the American Pacific Northwest and parts of Manitoba. It is restricted to the western part of the continent. As its name suggests, it is commonly found on potato and tomato crops, but has a species range that encompasses over 40 species of solanaceous plants and as many as 20 genera. Breeding hosts are generally recognised as being restricted primarily to Solanaceae, including important crop and common weed species, and a few species of Convolvulaceae, including bindweed and sweet potato. On some plants, especially potato, feeding of the nymphs causes a condition called psyllid yellows, presumed to be the result of a toxin. Both nymphs and adults can transmit the bacterium Candidatus Liberibacter.

Zebra chip is a recently diagnosed disease of potatoes associated with psyllid infestation and caused by species of the gram-negative bacterium, Candidatus Liberibacter. The tubers frequently have discolouration which becomes more clear during frying of chips. This disease causes very significant losses to farmers when it occurs as the potatoes are not suitable for making into chips or fries.