THE ESSENTIAL OIL EXTRACTED FROM Thymus kotschyanus BOISS. HOHEN AS A NATURAL SUBSTANCE FOR MANAGEMENT OF THE LESSER GRAIN BORER, Rhyzopertha dominica F.

Plant essential oils as promising bio-rational agents have been considered for management of damaging insect pests because they are naturally bio-degradable and safe to the non-target organisms. In the present study, the fumigant toxicity of essential oil from Thymus kotschyanus aerial parts was assessed against a major Coleopteran insect pest Rhyzopertha dominica and this bio-effect was optimised and modelled using Response Surface Methodology (RSM). Optimization of the fumigant toxicity displayed a concentration of 51.720 μl L-1 was adequate to kill 72.752% of insect population after 60.0 h exposure time. The best model for predicting of insecticidal effect was a third-grade model. Results of the present study recommended a high potential of T. kotschyanus essential oil for management of a major stored-product insect pest R. dominica and prediction of this bio-effect using response surface methodology.