Diversity and Abundance of Associated Insect Pests in Stored Dry Cocoa Beans of Southwest Nigeria

Abstract

Cocoa bean is a vital raw material in the production of beverage, animal feed, medicines and cosmetics which had played significant importance in Nigerian revenue prior to oil discovery. Its production has declined due to a number of factors among which are quantitative and qualitative losses by insect pests. Diverse species of insects attack dry cocoa beans in store and their pest status needs to be determined for effective control. This study examined diversity and abundance of emerging insect pests from collected cocoa samples in locations from Southwestern Nigeria. Four cocoa producing states namely Ekiti, Ondo, Osun and Oyo were chosen for this study. Four towns/villages were selected in each state from where1kg of dry cocoa beans each was collected from four cocoa stores/warehouses and bulked to represent the town/village. 750g of the beans was weighed in improvised culture cage in four replicates for each location. The experiment was laid out in a Completely Randomized Design at the Entomology laboratory of CRIN, Ibadan. Emerging insect species were counted, identified and added at thirty days interval for 120days. Ephestia cautella and Corcyra cephalonica were more abundant in all locations than populations of Plodia intepuctuella, Araecerus fasciculatus and Tribolium casteneum.