氰氟虫腙对小菜蛾阿维菌素抗性和敏感种群的亚致死效应(英文)

在实验室条件下采用生命表技术研究了氰氟虫腙亚致死剂量（LC₂₅）对小菜蛾Plutella xylostella阿维菌素抗性（AV-R）和敏感（AV-S）种群的亚致死效应， 旨在为小菜蛾对阿维菌素的抗性治理提供理论基础。结果表明： 氰氟虫腙对小菜蛾3龄幼虫抗性种群的LC₅₀和LC₂₅分别为0.24 mg/L和0.09 mg/L； 对敏感种群的LC₅₀和LC₂₅分别为0.20 mg/L和0.07 mg/L。氰氟虫腙亚致死剂量0.09 mg/L 处理小菜蛾后， 对处理代的影响表现为显著降低处理种群的化蛹率、 蛹重、 羽化率、 繁殖力； 明显延长蛹期， 缩短成虫产卵期和寿命； 对子代种群的影响表现为显著降低卵的孵化率、 幼虫各龄期的存活率， 延长发育历期。处理种群的内禀增长率（r_m）、 周限增长率（λ）和净增值率（R₀）显著低于对照种群（P<0.0001）。亚致死剂量的氰氟虫腙对小菜蛾抗性种群的影响大于敏感种群， 对处理代种群的影响大于子代种群。氰氟虫腙亚致死剂量可以极大地影响小菜蛾尤其是阿维菌素抗性种群的种群动态， 因此氰氟虫腙对于小菜蛾的抗性治理具有积极的作用。

Sublethal effects of metaflumizone on abamectin-resistant and susceptible strains of the diamondback moth, Plutella xylostella ( Lepidoptera: Plutellidae)

In order to provide the theoretical basis for the management of the diamondback moth,Plutella xylostella(L.) resistant to abamectin,the sublethal effects of metaflumizone on the experimental populations of both abamectin-resistant(AV-R) and susceptible(AV-S) strains of P.xylostella were evaluated by means of the life table technology.The results showed that the estimated LC50 and LC25 values of leaf dip bioassay of metaflumizone on the 3rd instar larvae were 0.24 and 0.09 mg/L for the AV-S strain,and 0.20 and 0.07 mg/L for the AV-R strain,respectively.Metaflumizone at the sublethal concentration(0.09 mg/L) tested decreased the pupation rate and pupal weight,prolonged the pupal duration and decreased the emergence rate,fecundity,oviposition duration and longevity of adults in the treated generation.Such treatment also decreased the hatchability and larval survival rate of the offsprings and their larval duration.Reproduction parameters such as the intrinsic rate of increase(rm),finite rate of increase(λ),and the net reproductive rate(R0) in populations treated with sublethal concentrations of metaflumizone were significantly lower than those of the control populations(P<0.0001).The results also showed that the sublethal concentration of metaflumizone had a greater effect on the AV-R strain than on AV-S strain,and had a greater effect on the current generation than on the offsprings.We conclude that the sublethal concentration of metaflumizone might have significant effects on the population dynamics of P.xylostella,especially the AV-R strain,and metaflumizone might be extremely useful for managing pest resistance to insecticides.