Antifeedant and ovipositional deterrent activity of medicinal plants of Western Himalaya on Plutella xylostella

Aim: Medicinal plants of Himalayan region is inadequately known for their role in pest management. The present study was conducted to assess the response of different extracts of Acorus calamus (L.) and Vitex negundo (L.) on antifeedant and ovipositional deterrent activity of Plutella xylostella. Methodology: Acorns calamus (Rhizome) and Vitex negundo (leaves) were taken as an experimental material. Methanol (polar solvent) and hexane (non-polar solvent) were used for extraction. Antifeedant and ovipostional deterrent effect of two plants were workout against Plutella xylostella. The data were statistically analysed by t-tests for paired comparisons. Results: Stronger ovipositional deterrent effects was observed in A. calamus (methanol extract) with higher oviposition deterrent indices (ODI) (38.7), followed by hexane extract of V. negundo. The leaves treated with plant extracts of A. calamus and V. negundo deterred the female of P. xylostella to some extent to lays eggs. After three days of treatment, methanol extract of A. calamus showed a residual deterrent effect to female of P. xylostella due to its low volatile nature. Interpretation:Application of methanol and hexane extracts of A. calamus and V. negundo on host plants render them less attractive and show ovipositional deterrent to females of P. xylostella.