THE SUSCEPTIBILITY OF VARIETIES OF BAMBARRA GROUNDNUTS TO INFESTATIONBY CALLOSOBRUCHUS-SUBINNOTATUS (PIC) (COLEOPTERA, BRUCHIDAE) DURING STORAGE

Twenty-one varieties of bambarra cultivated in Nigeria were compared w ith respect to their susceptibility to Callosobruchus subinnotatus (Pi c.). The bruchids developed fastest on varieties TVSU 155 and TVSU 702 . Development from the middle of oviposition to the emergence of the f irst filial adults lasted 32.8 and 32.0 days, respectively. Developmen t was slowest on TVSU 1033, lasting 42.6 days. The highest number of f irst filia (F1) adults emerged from varieties TVSU 11,TVSU 702 and TVS U 1231, while the lowest number emerged from TVSU 688. Susceptibility indices calculated for the varieties showed that TVSU 702 was the most susceptible variety, while TVSU 346 and TVSU 1033 were the least susc eptible varieties. Losses associated with varietal infestation, assess ed in terms of weight of bambarra consumed by the bruchids were high f or highly susceptible varieties and low for the least susceptible ones .