Evaluation of fumigant toxicity of orange peel Citrus sinensis (L.) essential oil against three stored product insects in laboratory condition

摘要

 In search for alternatives of conventional pesticides, plant essential oils have been widely investigated. Essential oils from aromatic plants are recognized as proper alternatives to chemical fumigants. In this research fumigant toxicity of essential oil of citrus peels was studied against three most common stored-product insects, Tribolium confusum, Callosobruchus maculatus and Rhyzopertha dominica. Five concentrations of essential oil were tested with four replicated at 24 and 48 h times with 30 adult insect in each replication. The citrus peels have medicinal and insecticide properties. The essential oil was obtained from the fruit peels using hydro distillation that were dried naturally at room temperature (23?27°C). After 24 h of exposure, the LC50 values were estimated to be 259, 158 and 118 μl/l air and after 48 h were 134, 106 and 86 respectively for each insect. It was found that R. dominica adults were more susceptible to the oil than others and T. confusum adults were less susceptible. Increasing the essential oil concentration and exposed time increased the fumigant toxicity of essential oils on insects. These results suggest that citrus peel essential oil as potential fumigant and may be used as a safe pesticide for the management of stored-product insects