LABORATORY EVALUATION OF SOME ENVIRONMENTALLY SAFE CHEMICALS AGAINST THE TWO SPOTTED SPIDER MITE, Tetranychus Urticae AND ITS PREDATOR INSECT, Stethorus Gilvifrons

Our study was directed to evaluate the relative toxicity of eight compounds; four pesticides (abamectin, cypermthrin, etoxazole and chlorfluazuron), two mineral oils (Chemesol and Supermasrona) and two plant extracts worm wood (Chrysanthemum morifolium) and Melia azedarach against adult females of the two spotted spider mites Tetranychus urticae and its predatory insect Stethorus gilvifrons using leaf-disc dip technique. The results indicated that, abamectin was the highest toxic compound to the adult females of T. urticae, followed by chlorfluazuron, Cypermethrin and etoxazole. Abamectin has a special effect to adult females of predator S. gilvifrons, followed by chlorfluazuron, cypermthrin, and etoxazole was the least toxic one. Moreover, chlorfluazuron, Cypermethrin and supremasrona were the most effective compounds on egg deposition of the adult female mites and caused the highest reduction in egg deposition comparable to the control, however, Etoxazole had the least effect on egg deposition. Cypermethrin caused the highest decrease in egg hatchability on leaf discs against egg stage of the T. urticae but etoxazole and worm wood extract were the least effective ovicidal action. Abamectin and Cypermethrin were the most effective chemicals that caused a decrease in prey egg consumption comparable to the control, while etoxazole had the least effect. Also, the predators egg deposited under the chemical treatment were less than that deposited under normal conditions (untreated). Etoxazolc and worm wood extract were the safest compounds that allowed the predator's eggs to hatch producing the next stages necessary as biological agent that minimize prey populations.