Abstract

Comparative studies of the effects of seven compounds and fenoxycarb (ecdysone agonist, an insect growth regulator), were conducted on Spodoptera littoralis (Boisduval, 1833). The compounds, orally administered, caused larval mortality proportional to the concentrations in the food source. Synthesized compounds initiated precocious molting and reproduction. In both cases, larvae were unable to complete the molting process and died in the old larval cuticle. Larvae contaminated by sublethal doses completed their development to adulthood. fenoxycarb is more active than is synthesized compound. LC50 for fenoxycarb is 25.943 ppm and for compound 2 is 26.505ppm. Application of fenoxycarb in the second half of embryogenesis caused precocious molting of eclosed larvae of the 2nd instar. Some morphological changes in the process of larval–pupal transformation was also observed

Keywords: Spodoptera littoralis (Boisd.); Fenoxycarb; Toxicity; Insect growth regulator