A Comparative Study of the Effect of Some Mineral and Plant Oils on Two Predacious Mites of the Family Phytoseiidae (Acari: Phytoseiidae)

The direct toxicity of some mineral and plant oils to adult females of the predacious mites, Amblyseius barkeri (Hughes) and Amblyseius zaheri Yousef and El-Borolossy were tested. KZ oil was the most toxic to females of A. barkeri and A. zaheri (LC50 = 0.391 and 0.308%, respectively). In contrast, Natur'l oil was relatively intoxic to females A. zaheri and A. barkeri. Bio-dux, Capl-2 and Natur'l oils have a close toxic effect for both predacious mites. Females of A. barkeri and A. zaheri suffered a depression in reproduction when sprayed with conc. = LC50 of each oil and kept on plant leaves previously treated with different oils. Laboratory studies indicated that the vegetable oil Natur'l oil was the least effective oil on all biological aspects of both predacious mites A. barkeri and A. zaheri in the laboratory