Toxicity of Four Insecticides to Phytoseiulus Macropilis (Banks) and P. Persimilis Athias‐henriot (Acarina: Phytoseiidae)

Commercial formulations of dimethoate, methomyl, fenvalerate and endosulfan were tested against a New Caledonian strain of Phytoseiulus macropilis and an Australian strain P. persimilis using a slide‐dip technique. The responses of the 2 species to fenvalerate, methomyl and endosulfan were similar, with fenvalerate being the most toxic and endosulfan the least. In contrast, dimethoate was 50x more toxic to P. macropolis than to P. persimilis at the LC50 level.