Fumigation Toxicity of Some Phyto Essential Oils against Stored Insect Pests of Maize

The adults of Sitophilus oryzae and Rhizopertha dominica were exposed to essential oils of geranium, lemonorasa and peppermint in the fumigation chamber at different concentrations with different exposure periods. Peppermint oil at all the concentrations caused 100% mortality of adults of S. oryzae with no progeny production and grain damage. It was significantly superior over other two oils. The order of toxicity was peppermint followed by geranium and lemongrass. In the case of R. dominica, except at lower doses, 100% mortality was also observed in peppermint oil where as both geranium and lemongrass caused nearly 1/4^th mortality at the same dose.