The gut microbiota has long been of research interests due to its nutritional importance for many insects. It has been demonstrated that diversity of gut microbiota in insects can be modulated by many factors, including habitats, feeding preference, etc. Besides, the community structure of gut microbiota could also be altered during the different life stages of host insects. With development of conventional culture-dependent technologies and advanced culture-independent technologies, comprehensive and deep understanding of the functions of gut microbiota and their relationship with host insects were achieved, especially for the nutrient metabolic process mediated by them. In this review, we summarized the gut microbiota composition, major methods for gut microbiota characterization, and vital nutrient metabolic process mediated by gut microbiota in different insects. The increasing knowledge on the modulation of gut microbiota will help us for the comprehension of the contribution of gut microbiota to the nutritional metabolism of insects, prompting their growth and health.

中文翻译：

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深入了解昆虫肠道微生物群的多样性和功能

由于肠道微生物群对许多昆虫的营养重要性，长期以来一直是研究兴趣。已经证明，昆虫肠道微生物群的多样性可以通过多种因素进行调节，包括栖息地、取食偏好等。此外，在宿主昆虫的不同生命阶段，肠道微生物群的群落结构也可能发生变化。随着传统的培养依赖技术和先进的培养独立技术的发展，人们对肠道微生物群的功能及其与宿主昆虫的关系，尤其是它们介导的营养代谢过程有了全面深入的了解。在这篇综述中，我们总结了肠道微生物群的组成、肠道微生物群特征的主要方法、以及由不同昆虫肠道微生物群介导的重要营养代谢过程。对肠道微生物群调节的认识不断增加，将有助于我们理解肠道微生物群对昆虫营养代谢的贡献，促进昆虫的生长和健康。