Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), the red flour beetle, is an important cosmopolitan pest of stored grains. Three ratios of male to female (3:7, 7:3 and 5:5) were reared on four flours, viz: millet, maize, sorghum and wheat, and the experiment which based on the various life stages were noted for larval development, pupal and adult. The results showed significant difference (P<0.05) between the maize grains and the other grains in larval, pupal and adult development of T. castaneum with different sex ratios. Thus the preparation and storage of ready to use flour, especially maize, for prolonged periods, should be de-emphasized amongst farmers, food handlers and households in Nigeria and Africa where facilities to keep abate T. castaneum are not available.
