Insecticidal activity of some essential oils against Rhyzopertha dominica on stored Wheat

To find out the insecticidal activity of four essential oils e.g. Murraya koenigii, Curcuma longa, Calistimone. citrinus and Citrus reticulata and their possible combinations were evaluated against Rhyzopertha dominica under laboratory condition. One hundred % mortality were observed in grain treated with M. koenigii and C. citrinus essential oil at 0.2% M. koenigii + C. reticulata, M. koenigii + C. citrinus, C. reticulata + C. citrinus essential oil at 0.1% each concentration in 6 hrs after treatment. The grain treated with C. reticulata at 0.2%, C. longa + C. citrinus essential oil at 0.1% each, M. koenigii + C. reticulata + C. longa, M. koenigii + C. reticulata + C. citrinus essential oil at 0.07% each and M. koenigii + C. reticulata + C. longa + C. citrinus essential oil at 0.05% each concentration showed 76.7, 73.3, 60.0, 96.7, 93.3% mortality in 6 hrs after treatment, respectively, which increased to 100% in 12 hrs after treatment. The most of the tested essential oils either alone or in combination killed R. dominica within 12 hrs after treatment. The evaluated essential oils and their possible combination suppressed the progeny development of R. dominica and did not affect the germination of wheat.