Abstract
Efficiency of tiametoxam was determined on population growth parameters of cabbage aphid, Brevicoryne brassicae L. (Hemiptera: Aphididae) using demographic toxicology by leaf spray method. At first, bioassay was performed. The LC50 values and confidence limits for thiamethoxam were 169.05 ppm (92.61–342.51). To evaluate, the sub-lethal effect of this insecticide on population growth parameters of cabbage aphid, LC25 and LC10 concentrations of tiametoxam were used at 58.8 and 22.05 ppm, respectively. Also, the LC50 value of insecticide on the life table estimates was measured. Experiments were carried out in the laboratory at 23 ± 1 °C, 60 ± 5% RH and 16:8 (L:D) photoperiod on cabbage seedlings, Brassica oleracea, var. capitata L. Net fecundity rate decreased in insecticide-treated populations. Intrinsic rates of increase (rm) were lower in tiametoxam treatment than in controls. There was a relative increase in intrinsic death rates of treated populations. The mean generation time and doubling time were also lower in population treated with insecticide than the control. There was a considerable reduction in the average numbers of nymphs reproduced per female as compared with the control. The average longevity of female adults in the control was significantly different (p < 0.05) from those treated with thiamethoxam.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call