Effect of Some Flavonoids on Survival and Development of Helicoverpa armigera (Hübner) and Spodoptera litura (Fab) (Lepidoptera: Noctuidae)

The aim of the study was to test the effect of three flavonoids on growth and survival of Helicoverpa armigera (Hüb) and Spodoptera litura (Fab.). A set of experiments were carried out with varying concentrations of three flavonoids namely chlorogenic acid, quercetin and rutin at 23±1oC on growth, development and mortality of larvae of pod borer Helicoverpa armigera and tobacco caterpillar Spodoptera litura in artificial diets. Rutin caused significant effect on the inhibition of H. armigera larvae in higher concentrations, where a proportion of larvae spent between 30-51 days in excess time in larval stage III-V instar which had negative impact on growth because of cessation of feeding by the larvae. H. armigera larvae formed cocoons of their diets and lay still inside the cocooned diet. Healthy H. armigera moth emergence was common in chlorogenic acid and quercetin, but the moths did not produce any progeny. In case of S. litura, rutin alone had a significant effect on arrested larval development, pupal mortality and malformed adults compared to artificial diets with quercetin and chlorogenic acid. The increase in concentrations of rutin did not show proportionate increase in mortality of the larvae. The average excess days at all concentrations of quercetin and chlorogenic acid ranged between 40-55 days. These results indicate a delay in development and suggests that rutin interferes in with physiological processes in both insects at the time of molting.