Assessment of Essential Oil of Acorus calamus L. and its Major Constituent β-Asarone in Post Harvest Management of Callosobruchus chinensis L.

Acorus calamus essential oil (EO) and its major constituent beta-asarone were subjected to insect repellant, mortality, oviposition deterrent and antifeedant efficacy on Callosobruchus chinensis L.. The EO showed greater efficacy against all the test parameters than the beta-asarone. The repellency experiments were carried out in a glass Y- shaped olfactometer having 60 ml aerial volume At 150 mu l, the EO showed 97.3 % repellency of C. chinensis while it was only 74.7 % in case of beta-asarone. The EO caused 100 % mortality of C. chinensis at 0.05 mu l/ml after 24 h exposure, while beta-asarone could exhibit only up to 46.5 %. In addition, the EO was found more efficacious in terms of oviposition, ovicidal, larvicidal and pupaecidal activity than the beta-asarone. The fumigant activity of A. calamus EO and beta-asarone against adults of C. chinensis was determined through impregnated paper assay in plastic jars of 500 ml capacity. At 0.15 mu l/ml EO caused 100 % antifeedant activity, thereby, completely protecting the chickpea seeds from insect damage and weight loss. EO also exhibited non phytotoxic nature on treated chickpea seed germination. The findings recommend A. calamus essential oil as a safe alternative of synthetic insecticides and as suitable candidate for pest management strategy against losses of food commodities caused by C. chinensis.