Botanical insecticides are known to affect insects through various mode of action which includes toxicity through ingestion, contact, antifeedant, growth inhibition, repellency, etc. The present study was aimed to explore the potential of Murraya paniculata leaf extracts against two important insect pests’, a storage pest, almond moth (Cadra cautella) and field crop pest, leaf-eating caterpillar (Spodoptera litura). It became apparent that among different stages of C. cautella, egg stage was more tolerant revealing the stage-specific toxicity. Maximum mortality (LC50 values of 1.495, 3.330 and 2.593% for hexane, acetone and methanol extracts, respectively) was recorded against adult stage after 72 h of exposure time whereas eggs stage proved to be tolerant stage. Hexane extract possessed the maximum antifeedant activity (AI50 = 1.820%) against S. litura after 24 h of exposure whereas after 48 h, methanol extract showed maximum antifeedant activity (AI50 = 4.269%). Maximum larval weight reduction was recorded in hexane extract (68.67%) at 3 days after treatment (DAT), whereas after 7 DAT acetone extract (55.54%) recorded the maximum larval weight reduction. Acetone extract had the maximum abnormalities whilst methanol extract had maximum larval mortality (94.29%). The present bioassays showed that solvent extracts of M. paniculata leaves possess contact, antifeedant and growth regulatory properties, and it has potential for biopesticide development.
