Laboratory studies to determine the efficacy of selected insecticides on tomato/potato psyllid.

Tomato/potato psyllid (Bactericera cockerelli) was first recorded in New Zealand in 2006, and is now a significant pest of solanaceous crops in both glasshouses and fields. Given the potential impact of this insect and its associated pathogen(s) on crop yields, immediate control options are required. Thirteen insecticides were selected for testing. In laboratory bioassays, insecticides were applied at recommended field rates as a spray (12 chemicals) or a seedling drench (1 chemical). The recorded mortality of tomato/potato psyllid nymphs 48 h after spraying with dichlorvos, lambda-cyhalothrin, methomyl, taufluvalinate, methamidophos and abamectin was 98-100%. After 168 h, applications of azadirachtin, spiromesifen, abamectin, spirotetramat and thiacloprid gave 82-100% mortality, while buprofezin, pymetrozine and imidacloprid drench gave 36-53% mortality of nymphs. Further tests are required to confirm the efficacy under cropping conditions.