Toxic Effects of Four Medicinal Plants on the Blood Sugar Trehalose of the Pulse Beetle Callosobruchus chinensis (Coleoptera: Bruchide)

. Different extracts of four medicinal plants Vetiveria zizanoides, Asparagus racemosus, Hyptis sauveolens and Citrus limon were assessed to demonstrate their toxic effects on the stored insect pest Callosobruchus chinensis. The four plants caused significant effects on the beetle and the effect was dose-dependent. In the study, insect blood sugar trehalose was analysed to check the effects of the treated plants. Trehalose was found to be decreased compared to control. Aqueous, ethanol and acetone extracts were used for the study. Acetone extracts of Citrus limon could produce more significant effects indicating the presence of more active components. The four medicinal plants thus proved to have strong insecticidal activity against the insect pests.