Insecticidal Actions of Some Botanicals to Storage Bruchid, Callosobruchus Maculatus (F.) on Stored Cowpea (Vigna unguiculata L. WALP.) Ogbaji Moses and Osuman Dorathy

Abstract

The effect of some botanicals on the control of cowpea (Vigna unguiculata (L.) Walp) against the bruchid, Callosobruchus maculatus during storage was investigated. Three plant materials used were powdered ginger, garlic and bitter leaf, while five varieties of cowpea used included Aloka, IAR48 (Big Brown), IT3629 (Big White), Iron Beans and IT84E-124 (Ife Brown). The experimental design used was a factorial laid out in a completely randomized design (CRD) with three replications. Results showed that there was a significant (P<0.05) difference among the cowpea varieties and plant materials used. An improved line, IT84E-124 (Ife Brown) resisted C. maculatus attack most during storage and subsequently gave the least weight reduction of 13.51 g during the entire storage period when compared to other varieties. Next was Aloka which gave 48.20 g, followed by IAR 48 (Big Brown), big white and lastly by iron beans (an unimproved line) with kthe highest weight reduction of 126.99 g. Among the treatments, bitter leaf gave the best protection against cowpea bruchid compared to the other plant materials giving least weight reduction of 1.09 g. Next to bitter leaf in efficacy was garlic. The interaction between cowpea varieties and plant materials used was also significant. The relative efficacy of these botanicals showed that they can also be used to preserve cowpea against C. maculatus during storage more so that they are environment friendly and have no negative side effect on human health.