Effect of Imidacloprid on Development of Plutella xylostella

Laboratory studies were conducted to find the total effect of imidacloprid on development of Plutella xylostella. LC₅₀ of imidacloprid on 3^rd instar larvae was ascertained and larvae were then, fed on cauliflower leaves impregnated with 0.002% of imidacloprid. Life table was constructed on the surviving adults obtained from treated 3^rd instar. The net reproductive rate (R₀) of surviving adult was 8.47 females/female in comparison to 10.99 in untreated control. The potential fecundity (P_f) was significantly decreased to 166.5, whereas intrinsic rate of increase (r_m) was 0.073 females/female/day as compared to 0.09 in untreated control. Mean length of generation (T_c) and corrected generation time (τ) was prolonged to 28.90 and 29.26 days, respectively. While doubling time (DT) was increased to 9.49 days in comparison to 7.7 days in untreated control.