Effect of Insecticide Resistance on the Biology and Morphometries of Cryptolestes ferrugineus (Stephens) (Coleoptera: Cucujidae)

The biology and morphometries of the three population of Cryptolestes ferrugineus (Stephens), which are distinct in their susceptibility to malathion, dichlorvos and phosphine were studied. Reduced fecundity prolonged incubation period, longer 4th instar grub, pupal and total developmental periods and reduced survival from egg to adult was observed with increased resistance to insecticides. Morphometric parameters like length of the grub, weight of the grubs, length and weight of pupae, length of male adults and weight of females also differed significantly, which were more in resistant strain compared to the others strains.