Antifeedant and larvicidal activities of Mentha pulegium on chickpea pod borer Helicoverpa armigera (Lepidoptera: Noctuidae).

This study investigates the insecticidal effect of the essential oil of Mentha pulegium L. on the second and third instar larvae of Helicoverpa armigera (Hübner). Antifeedant, contact toxicity and systemic toxicity of M. pulegium essential oil were evaluated using four concentrations and an untreated control under laboratory conditions. M. pulegium essential oil showed high level of antifeedant activity at 74.15%, and 61.72% when applied on the second instar larva and third instar larvae, respectively. The second instar larva was also more susceptible to systemic toxicity than the third instar larva LC50 1.80% and 3.80% at 24 h, respectively. Contact toxicity induced with LC50 values of 1.31% and 1.085% after 3 and 6 h on the second instar larva, respectively, and with LC50 values of 2.39% and 2.33% after 3 and 6 h on the third instar larva, respectively. This study showed that there is potential for using M. pulegium essential oil to formulate a biopesticide for the control of H. armigera larvae on chickpea.