Bioactivity of Anacardium occidentale (L) and Allium sativum (L) Powders and Oils Extracts against Cowpea Bruchid, Callosobruchus maculatus (Fab.) [Coleoptera: Chrysomelidae]

Abstract

The powders and oils extracts of Anacardium occidentale (L.) seeds and Allium sativum (L.) bulbs were tested as contact insecticides against the cowpea bruchid, Callosobruchus maculatus (Fab.) in cowpea seeds. The powders were incorporated at rates 1, 2.5 and 5/20g of cowpea seeds and acetone extracts of the plants were also applied at 0.5, 1 and 1.5ml per 20g of cowpea seeds to assess contact mortality of adult insect, oviposition, adult emergence and damage assessment. The results obtained showed that at 72 hours; 1, 2.5 and 5/20g of cowpea seeds evoked 63.3, 80 and 100% adult mortality of the cowpea bruchid while the corresponding results for A. sativum were 60.7, 73.3 and 100% mortality respectively. All concentration of acetone extracts that were used evoked 100% mortality of C. maculatus after 72 hours of post treatment. Complete protection of seeds and complete inhibition of adult emergence in both powders and extracts of A. occidentale and A. sativum were achieved. The results obtained from this research revealed that powders and extracts of A. occidentale seeds and A. sativum bulbs were effective in controlling cowpea bruchid, C. maculatus in stored cowpea seeds.