Investigation into Insecticidal Activity of Mentha arvensis and Mentha pulegium Essential Oils on Callosobruchus maculatus

Effects of Mentha arvensis L. and Mentha pulegium L. essential oils were investigated against oviposition deterrence, egg hatching and adults' mortality of Callosobruchus maculatus F. Essential oils were obtained by dry leaves that were subjected to hydrodistilation using a modified Clevenger-type apparatus. All experiments were conducted at 25±1ºC, 65±5 % R.H. in the dark condition with 5 replications for each essential oil. Results indicated that increasing the essential oil concentrations resulted in increase of insecticidal activity of essential oils on eggs, adults and oviposition deterrence. At the highest concentration tested (60 µl/l air), of M. pulegium and M. arvensis essential oils, 89.7 and 83.8% of adults were killed, respectively. Oviposition deterrence of M. pulegium was more than M. arvensis; however, egg hatching effects of both essential oils were not significantly different. According to the data probit analysis, LC50 for adults and eggs of C. maculatus were found to be 1.51 and 0.98 µl/l air of M. pulegium oil and 1.82 and 1.1 µl/l air essential of M. arvensis. The results suggest that essential oils of these aromatic plants could be used as botanical fumigant to protect grains against C. maculatus.