Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.
College of Plant Science, Tarim University/Key Laboratory of Production and Construction Corps of Agricultural Integrated Pest Management in Southern Xinjiang, Aral, China.
Pest Manag Sci. 2021 Jul;77(7):3406-3418. doi: 10.1002/ps.6385. Epub 2021 Apr 17.
Aphis gossypii, a polyphagous and recurrent pest induced by pesticides, causes tremendous loss crop yields each year. Previous studies on the mechanism of pesticide-induced sublethal effects mainly focus on the gene level. The symbiotic bacteria are also important participants of this mechanism, but their roles in hormesis are still unclear.
In this study, life table parameters and 16S rRNA sequencing were applied to evaluate the sublethal and transgenerational effects of sulfoxaflor on adult A. gossypii after 24-h LC (6.96 mg L ) concentration exposure. The results indicated that the LC of sulfoxaflor significantly reduced the finite rate of increase (λ) and net reproductive rate (R ) of parent generation (G0), and significantly increased mean generation time (T) of G1 and G2, but not of G3 and G4. Both reproductive period and fecundity of G1 and G2 were significantly higher than those of the control. Furthermore, our sequencing data revealed that more than 95% bacterial communities were dominated by the phylum Proteobacteria, in which the maximum proportion genus was the primary symbiont Buchnera and the facultative symbiont Arsenophonus. Compared to those of the control, the abundance and composition of symbiotic bacteria of A. gossypii for three successive generations (G0-G2) were changed after G0 A. gossypii was exposed to sulfoxaflor: the diversity of the bacterial community was decreased, but the abundance of Buchnera was increased (G0), while the abundance of Arsenophonus was decreased. Contrary to G0, G1 and G2 cotton aphid exhibited an increased relative abundance of Arsenophonus in the sublethal treatment group.
Taken together, our results provide an insight into the interactions among pesticide resistance, aphids, and symbionts, which will eventually help to better manage the resurgence of A. gossypii. © 2021 Society of Chemical Industry.
棉蚜是一种多食性、反复发作的害虫，会导致每年农作物产量的巨大损失。先前关于农药诱导亚致死效应的机制研究主要集中在基因水平。共生菌也是该机制的重要参与者，但它们在激素作用中的作用仍不清楚。
本研究应用生命表参数和 16S rRNA 测序技术，评估了 24 小时 LC（6.96mg/L）浓度暴露后，棉蚜成虫对噻虫嗪的亚致死和转代效应。结果表明，噻虫嗪的 LC 显著降低了亲代（G0）的有限增长率（λ）和净生殖率（R），显著增加了 G1 和 G2 的世代平均时间（T），但对 G3 和 G4 没有影响。G1 和 G2 的生殖期和繁殖力均显著高于对照组。此外，我们的测序数据显示，超过 95%的细菌群落由变形菌门主导，其中最大比例的属是主要共生菌布赫纳菌和兼性共生菌沃巴赫氏体。与对照组相比，亲代（G0）棉蚜暴露于噻虫嗪后，连续三代（G0-G2）的共生细菌丰度和组成发生了变化：细菌群落的多样性降低，但布赫纳菌的丰度增加（G0），而沃巴赫氏体的丰度降低。与 G0 相反，G1 和 G2 棉蚜在亚致死处理组中表现出沃巴赫氏体相对丰度的增加。
综上所述，我们的研究结果为农药抗性、蚜虫和共生体之间的相互作用提供了新的认识，这将有助于更好地管理棉蚜的卷土重来。
