Gloder Gabriele, Bourne Mitchel E, Verreth Christel, Wilberts Liesbet, Bossaert Sofie, Crauwels Sam, Dicke Marcel, Poelman Erik H, Jacquemyn Hans, Lievens Bart
CMPG Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department M2S, KU Leuven, Willem De Croylaan 46, 3001, Leuven, Belgium.
Leuven Plant Institute (LPI), KU Leuven, 3001, Leuven, Belgium.
Anim Microbiome. 2021 Oct 15;3(1):73. doi: 10.1186/s42523-021-00135-y.
The microbiome of many insects consists of a diverse community of microorganisms that can play critical roles in the functioning and overall health of their hosts. Although the microbial communities of insects have been studied thoroughly over the past decade, little is still known about how biotic interactions affect the microbial community structure in and on the bodies of insects. In insects that are attacked by parasites or parasitoids, it can be expected that the microbiome of the host insect is affected by the presence of these parasitic organisms that develop in close association with their host. In this study, we used high-throughput amplicon sequencing targeting both bacteria and fungi to test the hypothesis that parasitism by the endoparasitoid Cotesia glomerata affected the microbiome of its host Pieris brassicae. Healthy and parasitized caterpillars were collected from both natural populations and a laboratory culture.
Significant differences in bacterial community structure were found between field-collected caterpillars and laboratory-reared caterpillars, and between the external and the internal microbiome of the caterpillars. Parasitism significantly altered the internal microbiome of caterpillars, but not the external microbiome. The internal microbiome of all parasitized caterpillars and of the parasitoid larvae in the caterpillar hosts was dominated by a Wolbachia strain, which was completely absent in healthy caterpillars, suggesting that the strain was transferred to the caterpillars during oviposition by the parasitoids.
We conclude that biotic interactions such as parasitism have pronounced effects on the microbiome of an insect host and possibly affect interactions with higher-order insects.
许多昆虫的微生物群由各种各样的微生物群落组成，这些微生物群落对其宿主的功能和整体健康起着关键作用。尽管在过去十年中对昆虫的微生物群落进行了深入研究，但对于生物相互作用如何影响昆虫体内和体表的微生物群落结构仍知之甚少。在受到寄生虫或寄生蜂攻击的昆虫中，可以预期宿主昆虫的微生物群会受到这些与其宿主紧密共生的寄生生物的影响。在本研究中，我们使用针对细菌和真菌的高通量扩增子测序来检验内寄生蜂菜蛾盘绒茧蜂的寄生作用会影响其宿主粉纹夜蛾微生物群这一假设。从自然种群和实验室培养物中收集了健康和被寄生的毛虫。
在野外采集的毛虫和实验室饲养的毛虫之间，以及毛虫的外部和内部微生物群之间，发现了细菌群落结构的显著差异。寄生显著改变了毛虫的内部微生物群，但未改变其外部微生物群。所有被寄生毛虫以及毛虫宿主体内寄生蜂幼虫的内部微生物群均以一种沃尔巴克氏体菌株为主，而健康毛虫中完全不存在该菌株，这表明该菌株是寄生蜂在产卵时传递给毛虫的。
我们得出结论，诸如寄生等生物相互作用对昆虫宿主的微生物群有显著影响，并可能影响与高阶昆虫的相互作用。
