Ovipositional Deterrence of Methanolic and Etherial Extracts of Five Plants to the Cowpea Bruchid, Callosobruchus maculatus (F.) (Coleoptera: Bruchidae)

Abstract

Methanol and diethyl ether extracts of Harmal, Rhazya stricta Decne.; neem seed kernels, Azadirachta indica A.Juss; cloves, Syzygeum aromarticum (L.); citrus peel and Ramram, Heliotropium bacciferum (Forssk-) were evaluated for their deterrence to oviposition by Callosobruchus maculatus (F.) on chickpeas in choice tests. Both extracts of all materials significantly reduced oviposition on treated seeds. Maximum deterrent effects (91.8%) were obtained in the neem seed methanol extract at 0.5% concentration, citrus peel O. l% ether extract (90.9%), R stricta 0.5% methanol extract (83.9%), and clove 0. 1% ether extract (80.0%). Methanol extracts of neem seeds and R. stricta evoked higher deterrent effects than their etherial extracts, whereas the responses for cloves and citrus peel were more pronounced in their ether extracts. H. bacirferum % deterrency due to both types of extracts were practically identical. The results encourage future incorporation of such plant extracts as ovipositional deterrents in stored-product lPM programmes.