The present study was carried out to evaluate three oils (basil, chamomilla and nigella) and malathion as reference against three important insects of stored products,rice weevil , Sitophilus oryzae,Lesser grain borer, Rhyzopertha dominica and red flour beetles, Tribolium castaneum using the bioassay method, mixing with media. Results obtained demonstrated that the chemical insecticide malathion was the most efficient agent as compared with the other tested toxic materials. The basil oil was

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... most efficient against S. oryzae followed by chamomilla and nigella. The emergence of S. oryzae adults showed significant differences between the control and all treatments. For R. dominica the chamomilla oil was the most effeicient followed by basil and nigella. The loss of wheat weight showed significant differences between control and treatments. For T. castaneum the chamomilla oil had the most adversed effect on the all parameters studied. It reduced the number of progeny and loss % wheat grain, and increased the % reduction in progeny. The germination percentages decreased with increasing the concentration and exposure period.