Data from: Parasitic wasp-associated symbiont affects plant-mediated species interactions between herbivores

Microbial mutualistic symbiosis is increasingly recognised as a hidden driving force in the ecology of plant–insect interactions. Although plant‐associated and herbivore‐associated symbionts clearly affect interactions between plants and herbivores, the effects of symbionts associated with higher trophic levels has been largely overlooked. At the third‐trophic level, parasitic wasps are a common group of insects that can inject symbiotic viruses (polydnaviruses) and venom into their herbivorous hosts to support parasitoid offspring development. Here, we show that such third‐trophic level symbionts act in combination with venom to affect plant‐mediated interactions by reducing colonisation of subsequent herbivore species. This ecological effect correlated with changes induced by polydnaviruses and venom in caterpillar salivary glands and in plant defence responses to herbivory. Because thousands of parasitoid species are associated with mutualistic symbiotic viruses in an intimate, specific relationship, our findings may represent a novel and widespread ecological phenomenon in plant–insect interactions.

微生物互利共生日益被视作植物-昆虫互作生态学中的隐性驱动因素。尽管与植物、植食动物相关的共生体显然会影响植物与植食动物之间的互作，但与更高营养级相关的共生体的效应却在很大程度上被忽视了。在第三营养级中，寄生蜂是一类常见昆虫，它们可将共生病毒——多分DNA病毒（polydnaviruses）与毒液注入其植食性宿主体内，以支持寄生蜂后代的发育。本研究表明，这类第三营养级共生体可与毒液协同作用，通过抑制后续植食动物物种的定殖，从而影响植物介导的互作。该生态效应与多分DNA病毒和毒液在毛虫唾液腺以及植物对植食作用的防御反应中诱导的变化相关。由于数千种寄生蜂物种与互利共生病毒存在紧密且特异的关联，本研究的发现或代表植物-昆虫互作中一种新颖且广泛存在的生态现象。