Department of Animal Ecology and Tropical Biology, University of Würzburg, Am Hubland, 97074 Wuerzburg, Germany.
Department of Environmental Science and Policy (ESP), University of Milan, Via Celoria 2. 20133 Milan, Italy.
FEMS Microbiol Ecol. 2022 Nov 26;98(12). doi: 10.1093/femsec/fiac137.
Despite growing interest in gut microbiomes of aculeate Hymenoptera, research so far focused on social bees, wasps, and ants, whereas non-social taxa and their brood parasites have not received much attention. Brood parasitism, however, allows to distinguish between microbiome components horizontally transmitted by spill-over from the host with such inherited through vertical transmission by mothers. Here, we studied the bacterial gut microbiome of adults in seven aculeate species in four brood parasite-host systems: two bee-mutillid (host-parasitoid) systems, one halictid bee-cuckoo bee system, and one wasp-chrysidid cuckoo wasp system. We addressed the following questions: (1) Do closely related species possess a more similar gut microbiome? (2) Do brood parasites share components of the microbiome with their host? (3) Do brood parasites have different diversity and specialization of microbiome communities compared with the hosts? Our results indicate that the bacterial gut microbiome of the studied taxa was species-specific, yet with a limited effect of host phylogenetic relatedness and a major contribution of shared microbes between hosts and parasites. However, contrasting patterns emerged between bee-parasite systems and the wasp-parasite system. We conclude that the gut microbiome in adult brood parasites is largely affected by their host-parasite relationships and the similarity of trophic food sources between hosts and parasites.
尽管人们对螫刺膜翅目昆虫的肠道微生物组越来越感兴趣，但到目前为止，研究主要集中在社会性蜜蜂、黄蜂和蚂蚁上，而非社会性类群及其幼虫寄生虫则没有得到太多关注。然而，幼虫寄生可以区分通过宿主溢出水平传播的微生物组成分和通过母亲垂直传播继承的微生物组成分。在这里，我们研究了四个幼虫寄生-宿主系统中的七个螫刺膜翅目物种的成虫肠道微生物组：两个蜜蜂-Mutillidae（宿主-寄生蜂）系统、一个 Halictidae 蜜蜂-杜鹃蜂系统和一个黄蜂-Chrysididae 杜鹃蜂系统。我们提出了以下问题：（1）亲缘关系密切的物种是否具有更相似的肠道微生物组？（2）幼虫寄生虫是否与宿主共享微生物组的成分？（3）与宿主相比，幼虫寄生虫的微生物组多样性和专业化程度是否不同？我们的研究结果表明，所研究类群的细菌肠道微生物组具有物种特异性，但宿主系统发育亲缘关系的影响有限，宿主和寄生虫之间共享微生物的作用较大。然而，在蜜蜂-寄生虫系统和黄蜂-寄生虫系统之间出现了相反的模式。我们得出结论，成年幼虫寄生虫的肠道微生物组在很大程度上受到其宿主-寄生虫关系以及宿主和寄生虫之间相似的营养食物来源的影响。
