氟啶虫胺腈亚致死浓度对桃蚜生长和繁殖的影响

【目的】氟啶虫胺腈属第4代新烟碱类药剂,研究旨在探讨氟啶虫胺腈亚致死浓度对F_0(当代)及F_1(第1代)桃蚜(Myzus persicae)生长发育和繁殖的影响,为氟啶虫胺腈的合理使用提供理论依据。【方法】氟啶虫胺腈对桃蚜的亚致死剂量采用波特喷雾塔法确定,将琼脂铺于玻璃培养皿底部,再将新鲜油菜叶片背面向上铺在琼脂上。挑取15头成蚜至油菜叶片上,置于波特喷雾塔下喷雾,药剂设置7个浓度,处理48 h后检查桃蚜死亡情况,采用POLO-Plus10.0软件计算LC_(10)和LC_(25)。采用建立生命表的方法评估氟啶虫胺腈亚致死剂量对桃蚜生长发育和繁殖的影响。评估药剂对F_0代桃蚜的影响时,分别以LC_(10)和LC_(25)喷施成蚜,48 h后将成蚜移至未着药叶片,单头饲养直至死亡。评估药剂对F_1代桃蚜的影响时,以LC_(10)和LC_(25)处理成蚜,48 h后将成蚜移至未着药叶片待其产蚜,24 h后随机选取初产若蚜单头饲养直至死亡,记录蚜虫存活及繁殖情况。采用SPSS16.0软件分析若蚜发育历期、成蚜寿命、单雌产蚜量及生命表参数差异显著性。【结果】根据室内生物测定结果,氟啶虫胺腈对桃蚜成蚜48 h的LC_(10)和LC_(25)分别为0.012和0.041 mg·L~(-1)。亚致死浓度的氟啶虫胺腈显著降低了F_0和F_1代桃蚜成蚜寿命、单雌产蚜量和产蚜历期,并表现为随药剂浓度增加,成蚜寿命、产蚜历期缩短,单雌产蚜量降低。LC_(10)和LC_(25)浓度处理F_0代桃蚜后,成蚜寿命分别为20.89和15.47 d,均显著低于对照的25.41 d;单雌产蚜量分别为56.51和27.33头,显著低于对照的71.02头;产蚜历期分别为20.74和14.37 d,显著低于对照的25.27 d;F_1代成蚜寿命分别为14.80和9.76 d,产蚜历期分别为12.03和8.59 d,单雌产蚜量分别为46.20和28.23头。与对照相比,LC_(10)浓度的氟啶虫胺腈处理显著延长了F_1代1龄若蚜的发育历期(1.73和2.21 d),LC_(25)浓度的氟啶虫胺腈处理显著延长了2龄若蚜的发育历期(1.43和1.58 d),其余龄期及整个若蚜期发育历期与对照相比均无显著差异。生命表参数分析表明,氟啶虫胺腈LC_(10)和LC_(25)浓度处理后桃蚜净增殖率R_0与对照相比显著降低,R_0分别为47.15、24.55和64.47。【结论】亚致死剂量的氟啶虫胺腈能够显著抑制F_0及F_1代桃蚜的寿命和繁殖力。

Sublethal Effects of Sulfoxaflor on the Growth and Reproduction of the Green Peach Aphid Myzus persicae

【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.