Effect of Nimbecidine and Neemazal on the developmental programming of cotton pest, Earias vittella

Abstract

The toxic effect of Nimbecidine and Neemazal on the reproductive ability of cotton pest, Earias vittella was evaluated under laboratory conditions. Sufficient number of male and female insects was treated with four different doses of Neemazal T/S (0.70, 1.10, 1.50 and 1.90 g/insect) and Nimbecidine (0.90, 1.05, 1.20 and 1.35 g/insect). Six males and six females were used for each treated dose and were paired to mate independently. Each such pair served as one replicate. Results show significant reduction in fecundity, hatchability and adult emergence as compared to that of control. A significant decrease (p<0.001 for each case) in hatchability up to 44% in Neemazal T/S and 32% in Nimbecidine treated Earias vittella were observed. The result also shows that both the pesticides may have a significant effect on the reproduction of the cotton pest, Earias vittella. Therefore, less expensive natural biopesticide could be an alternative for chemical pesticides.