[Sublethal effect of chlorpyrifos on dynamics of experimental Tetranychus cinnabarinus population]

By using Jackknife technique and Wilcoxon (Gehan) statistic method, the LC35 sublethal effect of chlorpyrifos on the population dynamics of Tetranychus cinnabarinus was studied in laboratory. The results showed that under the conditions of 30 degrees C +/- 1degrees C, (70 +/- 15) % RH and a photoperiod of 16L: 8D, there were no significant differences in the longevity of female adult, F1 hatchability, and sex ratio of T. cinnabarinus between chlorpyrifos treatment and the control, but the total oviposition (42.37 +/- 2.270) and the intrinsic rate of increase (0.3279 +/- 0.0033) in chlorpyrifos treatment were significantly lower than those (52.50 +/- 2.433 and 0.3717 +/- 0.0043, respectively) in the control.