Insect herbivores have ubiquitous associations with microorganisms that have major effects on how host insects may interact in their environment. Recently, increased attention has been given to how insect gut microbiomes mediate interactions with plants. In this paper, I discuss the ecology and physiology of gut bacteria associated with insect herbivores and how they may shape interactions between insects and their various host plants. I first establish how microbial associations vary between insects with different feeding styles, and how the insect host physiology and ecology can shape stable or transient relationships with gut bacteria. Then, I describe how these relationships factor in with plant nutrition and plant defenses. Within this framework, I suggest that many of the interactions between plants, insects, and the gut microbiome are context-dependent and shaped by the type of defense and the isolates present in the environment. Relationships between insects and plants are not pairwise, but instead highly multipartite, and the interweaving of complex microbial interactions is needed to fully explore the context-dependent aspects of the gut microbiome in many of these systems. I conclude the review by suggesting studies that would help reduce the unsureness of microbial interactions with less-defined herbivore systems and identify how each could provide a path to more robust roles and traits.

中文翻译：

---

昆虫肠道微生物群系与植物防御相交处的复杂关系。

昆虫食草动物与微生物无处不在，对宿主昆虫如何在其环境中相互作用产生重大影响。最近，人们越来越关注昆虫肠道微生物群如何介导与植物的相互作用。在本文中，我将讨论与食草动物相关的肠道细菌的生态学和生理学，以及它们如何影响昆虫与各种寄主植物之间的相互作用。我首先确定不同饲喂方式的昆虫之间的微生物联系如何变化，以及昆虫寄主的生理和生态如何与肠道细菌形成稳定或短暂的关系。然后，我描述了这些关系如何影响植物营养和植物防御。在这个框架内，我建议植物，昆虫，肠道微生物组与环境有关，并受防御类型和环境中分离菌的影响。昆虫与植物之间的关系不是成对的，而是高度多方的，复杂的微生物相互作用需要相互交织才能充分探索其中许多系统中肠道微生物组的背景相关方面。我通过建议可以帮助减少微生物与不确定性草食动物系统相互作用的不确定性并确定每种方法如何提供更稳健的作用和性状的途径来结束本综述。并且需要复杂的微生物相互作用的交织，才能充分探索其中许多系统中肠道微生物组的上下文相关方面。我通过建议可以帮助减少微生物与不确定性草食动物系统相互作用的不确定性并确定每种方法如何提供更稳健的作用和性状的途径来结束本综述。并且需要复杂的微生物相互作用的交织，才能充分探索其中许多系统中肠道微生物组与环境相关的方面。我通过建议可以帮助减少微生物与不确定性草食动物系统相互作用的不确定性并确定每种方法如何提供更稳健的作用和性状的途径来结束本综述。