低浓度吡虫啉胁迫对麦二叉蚜多个世代生存和繁殖的作用

Stress of Low Concentration of Imidacloprid on the Transgenerational Survival and Reproduction of Schizaphis graminum(Rondani)

[目的]研究采用低浓度吡虫啉处理麦二叉蚜Schizaphis graminum(Rondani)后,对其室内种群亲代及子代的胁迫作用,以揭示麦二叉蚜种群多个世代的生存和繁殖对低浓度杀虫剂的响应,为田间制定有效的可持续综合防控措施提供理论依据。[方法]采用吡虫啉LC20浓度处理亲代麦二叉蚜后,检测低浓度吡虫啉对麦二叉蚜种群亲代及连续2个子代世代的存活和繁殖的影响。[结果]吡虫啉LC20浓度处理麦二叉蚜后,F0世代种群的存活率及寿命、产蚜量、生殖历期和单次产蚜数最高时日均高于对照组,仅单次产蚜数最高时日与对照组存在显著差异;在F1及F2世代中,LC20组试虫的寿命、产蚜量、生殖历期和单次产蚜数最高时日与对照组无显著差异;在不同世代间,麦二叉蚜LC20组除每雌产蚜总数在连续3个世代中无显著差异外,其F1及F2世代种群的平均寿命、生殖历期及单次产蚜数最高时日均比F0世代种群显著缩短。[结论]麦二叉蚜亲代在受到吡虫啉LC20浓度的胁迫后,对其亲代麦蚜的存活、生长和繁殖无明显影响;随着世代数增加,未发现暴露于低浓度吡虫啉后可刺激麦二叉蚜子1代或子2代成蚜增殖,其LC20组2代子代麦二叉蚜的存活和繁殖参数均与对照组无显著差异。

[Aims]This study aims to assess the stress of the low concentration of imidacloprid on the transgenerational survivorship and fecundity of Schizaphis graminum after the parental individuals were exposed to the sublethal dose of the imidacloprid.It was beneficial for revealing responds of survival and reproduction of experimental populations of S.graminum to the low concentration of imidacloprid through multiple generations,which could provide a theoretical basis for the formulation of effective and comprehensive control measures in the field.[Methods]The transgenerational survivorship and fecundity of S.graminum were detected after the parental individuals were exposed to the LC20concentration of imidacloprid.[Results]The individuals exposed to the sublethal dose of the imidacloprid (the LC20group) demonstrated a light increase in the survival,longevity,number of offspring per female,reproductive period of parental generation,and time to peak nymph production compared with the control aphids,while only the difference between time to peak nymph production of the two groups was significant by using statistical analyses.Moreover,these survival and reproductive parameters of the LC20group in both F1 and F2 generations displayed no differences from those of the control.In addition,there was no significant difference for number of offspring per female among individuals of three generations in the LC20group,while values of aphids in the F1 and F2 generations,including longevity,reproductive period of parental generation and time to peak nymph production,were significantly lower than aphids in the F0 generation.[Conclusions]It suggested that the stress of the sublethal concentration of the imidacloprid could not exert positive or negative effects on the survival and reproductive parameters of S.graminum in parental generation.In addition,as the number of generations increased,the exposure of the low concentration of the imidacloprid on parental aphids could not stimulate the increase of the reproductive rate of the successive first and second filial aphids.The survival and reproductive parameters of the two filial generations of the LC20group had no significant difference from those of the control.