Effect of very low concentration (LC10) of chlorfluazuron insecticide on life table parameters of the cabbage aphid Brevicoryne brassicae (Hemiptera: Aphididae)

Brevicoryne brassicae (L.) is one of the major pests of cruciferous crops that invades cabbage fields and leave white ash colonies. Due to the recommendation and suitable effect of chlorfluazuron against Plutella xylostella, in this study, the lethal and sub-lethal effect of this insecticide was evaluated on the population of cabbage aphid as a side pest. The method used in the experiments was insecticide spraying on leaves containing aphids. LC10 concentration (25.90 ppm) was used to investigate the sublethal effects of the insecticide on cabbage aphid. According to the results, the female lifespan/longevity was significantly reduced by sublethal concentration. The fertility mean of control and treatment exposed by chlorfluazuron sub lethal dose was 25.38 and 21.05 nymphs/female, respectively. Results indicated that the sublethal concentration (LC10) also affected progeny of treated adult aphids. Accordingly, the sublethal concentration of Chlorfluazuron significantly reduced intrinsic rate of increase (r) and finite rate of increase (λ) in comparison with control. Net reproductive rate (R0) in control and sublethal concentration treatment were 23.92 and 4.87 nymphs per female, respectively with meaningful difference. However, the mean generation time (T) between control and treated aphids have not considerable statistical difference. Based on the findings of the present study, even a very low concentration (LC10) of chlorfluazuron insecticide can be effective in cabbage aphid control and keep its population in low levels.