Laboratory studies were conducted to assess the infestation potential of Callosobruchus maculalus (Fab.) on 12 elite and one local cowpea cultivars which were stored under subtropical conditions. Index of susceptibility, loss in grain quality and the number of adult progeny that emerged from previously infested grain were the criteria used to assess the vulnerability of the cowpeas to post-harvest infestation. Cultivars TV × 309–1C and TV × 1193–10F showed some degree of resistance to post-harvest infestation by C. maculalus and could therefore be stored safely for a relatively long time. TV × 1192–01D and TV × 1999-1D were the most susceptible cultivars to post-harvest attack by C. maculatus. Length of storage adversely affected the ability of the cultivars to resist the insect attack. Crop resistance, adequately supplemented with good sanitation, can be profitably applied to control insect infestations in grains during storage.
