TOXICOLOGICAL STUDIES OF SOME PESTICIDES ON CERTAIN VEGETABLE CROPS PESTS I- TOXICITY AND JOINT ACTION EFFECTS OF SOME COMPOUNDS AGAINST CERTAIN VEGETABLE CROPS PESTS

The present study indicates the interaction between acaricides and fungicides, (i.e., Fenpyroximate, fenarimol and sulphur) and some of their alternatives (i.e. mineral oil, Kz-oil and black pepper extract) against both of the two-spotted spider mite Tetranychus urticae and the fungi,  Rhizoctonia solani and Fusarium moniliforme which cause damping-off disease to vegetable crops (i.e. tomato, cucumber and pepper) as well as  Alternaria solani which cause early blight disease of tomatoes and potatoes and was found associated with T. urticae under laboratory conditions. This would lead us to pick the compounds which could be used for the control of spider mite and associated fungi in the same time. The evaluation included also the joint toxic effects of tested compounds mixtures against adult female mites and tested fungi under laboratory conditions. The results showed that Animal dipping technique method was more toxic than leaf-disc dipping technique method. Fenpyroximate was the most toxic compound to adult female mites, the mineral oil (kz-oil) was gave moderate toxic effect and Fenarimol, black pepper extract and sulphur were the least toxic compounds to adult female mites. Fenarimol was the most toxic compound to all tested fungi. Fenpyroximate and black pepper extract gave moderate toxic effects,Sulphur was the least toxic compound and Kz-oil showed no toxic effects to all tested fungi up to concentration of 10⁴ p.p.m.The results showed that, the poteniation effect against the adults of T. urticae was obtained with the mixtures of fenpyroximate + fenarimol, fenpyroximate + Kz-oil, fenarimol + sulphur, Kz-oil + black pepper extract and black pepper extract + sulphur . The results showed that all tested compounds reduced the mean numbers of the moving stages of mite during the first  three days after treatment ,with different percent of reduction of the number according variety of plants.The data showed also that fenpyroximate and kz-oil gave high residual effect against the tested mite, while the activity of fenarimol, sulphur and black pepper extract were decreased by increasing the time after application. Results showed that all the tested combinations gave an antagonistic effect against Fusarium moniliforme except the combination of fenpyroximate + sulphur which gave an additive effect.Results showed that the combination of fenpyroximate + black pepper extract showed synergistic effect against Rhizoctonia solani .The mixtures of fenarimol + fenpyroximate, fenarimol + Kz-oil, fenarimol + sulphur, fenpyroximate + sulphur and sulphur + kz-oil. showed  antagonistic effectagainst Alternaria solani: