The effect of indoxacarb and five other insecticides on Phytoseiulus persimilis (Acari: Phytoseiidae), Amblyseius fallacis (Acari: Phytoseiidae) and nymphs of Orius insidiosus (Hemiptera: Anthocoridae).

A laboratory study assessed the contact toxicity of indoxacarb, abamectin, endosulfan, insecticidal soap, S-kinoprene and dimethoate to Amblyseius fallacis (Garman), Phytoseiulus persimilis Athias-Henriot and nymphs of Orius insidiosus (Say). Amblyseius fallacis is a predacious phytoseiid mite and an integral part of integrated pest management (IPM) programmes in North American apple orchards. The other two beneficials are widely used in greenhouses to manage various arthropod pests infesting vegetable and ornamental crops. Indoxacarb is a slow-acting insecticide, so toxicity data were recorded 7 days post-treatment when the data had stabilised. It showed no toxicity to O. insidiosus nymphs or to A. fallacis or P. persimilis adults. The LC50 values for O. insidiosus nymphs and P. persimilis could not be estimated with their associated confidence limits, because the g values were greater than 0.5 and under such circumstances the lethal concentration would lie outside the limits. The LC50 for A. fallacis was 7.6x the label rate. The fecundity of P. persimilis was reduced by 26.7%. The eclosion of treated eggs from both species of beneficial mites was not affected adversely. Among the other pest control products, S-kinoprene and endosulfan affected adversely at least one species of the predators, whereas dimethoate, abamectin and insecticidal soap were very toxic to all three beneficials. Indoxacarb should be evaluated as a pest control product in IPM programmes.