关键词: 氟啶虫胺腈, 新烟碱类杀虫剂, 桃蚜, 生命表, 生物测定, 波特喷雾塔

Abstract: 【Objective】 Sulfoxaflor is the fourth generation of neonicotinoids. In this study, the sublethal effects of this pesticide on the development and reproduction of the F₀ (parental) and the F₁ (first generation) green peach aphid Myzus persicae were investigated to provide a theoretical basis for proper usage of this insecticide. 【Method】 The sublethal concentrations of LC₁₀ and LC₂₅ were determined by the bioassay method of Potter spray tower. The agar was placed at the bottom of the glass dish, while leaf discs were placed with their adaxial surface downward onto agar. Fifteen adult aphids were transferred onto each leaf disc. Insecticide were sprayed to the leaf disc with aphids by using the Potter spray tower under seven concentrations. Mortality of the aphids was recorded 48 h later. LC₁₀ and LC₂₅ were estimated using POLO-Plus10.0 software. Sublethal effects of sulfoxaflor on the development and reproduction of the green peach aphid was evaluated by the method of establishing a life table. For the F₀ aphid, sulfoxaflor was sprayed on the adult aphids at the concentrations of LC₁₀ and LC₂₅. After the application of the insecticide for 48 h, the adults were moved to fresh leaves without insecticide and reared separately until death. For the F₁ aphid, sulfoxaflor was sprayed on the adult aphids at the concentrations of LC₁₀ and LC₂₅. After the application of insecticide for 48 h, the adults were moved to fresh leaves without insecticide. When the adult aphid produced nymphs for 24 h, one nymph was randomly selected and reared separately until death. The survival and reproduction of each aphid were recorded. The statistical differences of the development duration of nymphs, the adult longevity, the number of nymph per aphid and the life table parameters of F₀ and F₁ were analyzed using SPSS 16.0.【Result】 According to the bioassay, the LC₁₀ and LC₂₅ of sulfoxaflor on the green peach aphid after 48 h were 0.012 and 0.041 mg·L^-1. Treatments with sublethal concentrations of sulfoxaflor significantly reduced the adult longevity, the number of nymph per aphid and the reproductive period of F₀ and F₁. The values reduced with the increase of the concentration of insecticide. After being exposed to the sublethal concentrations LC₁₀ and LC₂₅ of sulfoxaflor, for the F₀ aphid, the average longevity of aphid adult was 20.89 and 15.47 d, respectively, shorter than that of control (25.41 d). The nymph number per aphid after treatment with LC₁₀ and LC₂₅ of sulfoxaflor was 56.51 and 27.33, respectively, significantly less than that of control (71.02), while the reproductive period was 20.74 and 14.37 d, respectively, significantly shorter than that of control (25.27 d). For the F₁ aphid, the average longevity of adult was 14.80 and 9.76 d, the reproductive period was 12.03 and 8.59 d, the nymph number per aphid after treatment with sulfoxaflor at LC₁₀ and LC₂₅ was 46.20 and 28.23, respectively. Compared with the control, treatment with sulfoxaflor at LC₁₀ significantly extended the development duration of 1st instar nymph (1.73 and 2.21 d), while treatment with sulfoxaflor at LC₂₅ significantly extended the development duration of 2nd instar nymph (1.43 and 1.58 d). However, there was no significantly difference in the other instar development duration and the total nymph period. Life table analysis showed that the net reproductive rate R₀ was decreased significantly after treatment with sulfoxaflor at LC₁₀ and LC₂₅ with the values of 47.15, 24.55, respectively, compared with the control with a value of 64.47. 【Conclusion】Sublethal concentrations of sulfoxaflor have inhibitory effects on adult longevity and fecundity of the F₀ and F₁ M. persicae.

Key words: sulfoxaflor, neonicotinoid, Myzus persicae, life table, bioassay, Potter spray tower