Insecticidal activity of essential oils from mint and Ajwain against pulse beetle Callosobruchus chinensis (L)

The present study evaluates the insecticidal activity of two essential Oil (EOs) mint (Mentha arvensis), and ajwain (Carum capyicum) against pulse beetle (Callosobruchus chinensis) (L). Contact toxicities of these were evaluated using parameters of lifecycle like total development period, numbers of eggs laid, adult emergence and adult longevity. Along with these detoxification enzyme inhibition activities of acetyl cholinesterase (AChE), alkaline phosphatase (ALP), transaminases enzymes-aspartate aminotransferases (AST) and alanine aminotransferases (ALT) and total protein were estimated. EOs were observed showing toxicity (mint LC₅₀ = 5.9 µl/ml and ajwain LC₅₀= 7.02 µl/ml). Exposure of EOs altered the lifecycle parameters significantly (p<0.01). The detoxification enzyme inhibition activities were also significant (p<0.01). Thus, it is concluded that these EOs can be recommended as safe and ecofriendly alternatives.