Fecundity Life Tables for Plutella xylostella L. at Two Temperatures and its Implication in IPM

At 20°C, the life cycle was 27.94±0.85 days. Adult females survival was 31%, females lived for 19.49±0.28 days, during which time 71.32±29.55 eggs/female were oviposited. The maximum contribution to fecundity (m_x=270) occurred on day 2 of adult life. At 30.5°C, larval development was completed in 10.40±0.84 days and females lived for 11.21±0.24 days. At 20°C the net reproductive rate (R₀) was 383.88 in a generation time of 32.89 days. The intrinsic rate of increase (r_m) was 0.1885 and the finite rate of increase (λ) was 1.207 times/female/day. On attaining stable age distribution, 99.4% of the population were in the immature stages with the egg stage representing the largest proportion. At 30.5°C, the life cycle was completed in 16.39±0.95 days. The net reproductive rate was 161.54 and the finite rate of increase was 1.322. Based on an intrinsic rate of increase of 0.2789, on reaching stable age distribution approximately 99.7% of the population existed in the immature stages.