New Zealand Plant Protection 66 (2013): 387
Zebra chip (ZC) is mottled browning discolouration of cooked potato crisps caused by the bacterium Candidatus Liberibacter solanacearum (CLso). ZC has caused significant problems in the New Zealand potato industry. Tomato-potato psyllid (Bactericera cockerelli) (TPP) is a vector for CLso. Surround® WP, formulated from nontoxic kaolin clay and a spreader-sticker, is effective in protecting fruit trees from various insect pests. Sulphur has been widely used to control arthropod pests, especially mites. Fosetyl-aluminium has no bactericide properties as such, but can change the host susceptibility to some bacteria, such as fire blight (Erwinia amylovora). A field trial, conducted at Pukekohe to determine the effects of kaolin clay, sulphur, and fosetyl-aluminium applied as foliar sprays, on TPP, potato yields, tuber dry matter content and incidence of ZC, found that, while not reducing ZC, sulphur demonstrated potential for reducing TPP nymph numbers in the crop. Kaolin and fosetyl-aluminium were not effective in controlling either TPP or ZC.
Copyright © 2013 New Zealand Plant Protection Society (Inc.).