The effect of topical application and oral administration of diflubenzuron on the feeding budget in the fifth instar larva of Papilio demoleus has been studied. The LD50 and LC50 values of diflubenzuron were 13.50 and 9.00 μg/larva/48 hr respectively. Topical application was found more efficacious in producing 50% mortality at a comparatively minimum dose of 9.00 μg. The growth efficiency was reduced by 44.54% in oral administration and 38.19% in topical application at the highest sublethal dose over that of control larvae. Not only the growth of the larvae of P. demoleus was inhibited, but the adults showed morphological deformities.
