Susceptibility of Spodoptera litura (Fabr.) to Diflubenzuron

Larvae of Spodoptera litura were reared on artificial diets fortified with different concentrations of diflubenzuron 25 WP. All larvae failed to reach pupal stage at 32 and 64 rpm while only 5% larvae survived at 16 ppm. Dead larvae become translucent in the beginning but later turned black. Larval period was extended at all concentrations. At 1 ppm only, 12.5% pupation and adult emergence was recorded. Rest of the larvae, which survived on various diets, showed the formation of larval pupal intermediates. LC50 was 3.34 ppm while LT50 ranged from 134.2 to 667 hours at different concentrations.