Bioassay of some pesticides on two-spotted spider mite Tetranychus urticae Koch and predatory mite Phytoseiulus persimilis A-H

Trial was carried out, under laboratory conditions to evaluation the responses of the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) and predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) as Turkish (Hatay) strain against three pesticides, which were selected from different groups. The responses (mortality, sensitivity) of mite populations against pesticides were estimated by calculation the median lethal concentration (LC50). According to LC50 values, predatory mite, P. persimilis shows oversensitivity for T. urticae against bifenthrin and dimethoate. Toxicity of bifenthrin and dimethoate were classified as harmful effect according to IOBC criteria. Hexythiazox was less toxic than the other pesticides and evaluated as harmless after 24 h and moderately harmful after 72 h to P. persimilis. For this reason, hexythiazox is suitable to suggest in IPM program and ensure the preservation of predatory strain into local agro-system.