Assessment Of The Damage Caused By Corcyra Cephalonica (Stainton) (Lepidoptera: Pyralidae) And Araecerus Fasciculatus (Degeer) (Coleoptera: Anthribidae) To Stored Cocoa Beans In Ghana

ABSTRACT The damage caused by Corcyra cephalonic a and Araecenus fasciculatus to cocoa beans was studied at the Research Department o f Quality Control Division o f COCOBOD, Tema. The study included breeding o f the two insects on cocoa beans to investigate the biology, fecundity and progeny production o f the two insect species. The free fatty acid level o f cocoa beans was also determined and the change in this level due to insect damage was calculated with respect to undamaged ones. The contaminants produced by these insects were also determined. Araecerus. fasciculatus did not breed on cocoa beans but C. cephalonica bred well on cocoa beans. Ten C. cephalonica larvae produced 608 adults after four months storage. C. cephalotiica bred better on crushed cocoa than whole cocoa beans. Developmental period of 33.8 days was recorded on crushed cocoa beans while 37.9 days were recorded on whole cocoa beans. Fecundity o f C. cephalonica was also higher on crushed cocoa beans compared to whole cocoa beans, laying 174 and 141 eggs, respectively. There was significant difference between the survival and establishment o f C. cephalonica and A. fasciculatus and hence the damage caused. C. cephalonica produced the highest quantity o f contaminants o f 77.2 g when alone and 67.8 g when introduced with A. fasciculatus. The highest percentage seed damage and weight loss of 46.7 and 13.3% were caused by C cephalonica when alone, respectively. The actual percentage seed damage and weight loss attributable to A. fasciculatus were 0.1 and 0.9%, respectively.. There was correlation between insect density and damage caused. The free fatty acid level of cocoa beans was increased by 0.17% and 0.13% when infested by C. cephalonica and A. fasciculatus, respectively.