昆虫共生微生物及其功能研究进展

昆虫体内共生微生物能够占到昆虫生物量的1%~10%，主要包括细菌、真菌、古菌和病毒。昆虫与共生微生物共进化形成共生体，共生微生物在昆虫生物学性状、多样性形成、生态适应性与抗逆性等多方面发挥着重要的作用。昆虫中的农作物害虫严重影响农业生产。本文对2000年以来农业害虫共生微生物的多样性、研究方法和功能机制、共生微生物之间的互作以及在害虫防控中的应用等方面的研究进展进行综述和展望。随着分子微生态学、宏基因组测序等先进研究方法的不断开发应用，对农业昆虫害虫共生微生物研究的广度和深度都有了突破。发现共生微生物主要通过以下方式影响宿主昆虫：(1)合成营养物质或产生消化酶促进宿主生长发育、拓展宿主生态位；(2)产生保护性代谢物直接保护宿主抵御胁迫，或通过调控寄主植物的防御反应间接地保护宿主；(3)产生活性物质调控宿主的生殖、交配、聚集和运动等行为。昆虫共生微生物的种类和数量在一定时空范围内维持动态变化并对宿主表型产生重要影响，是宿主、环境、共生微生物互作因素之间收益权衡的结果。因此建议进一步开展以下研究：影响共生体形成和维持的分子机制；在更多时空维度上研究共生微生物、宿主、寄主、天敌和环境之间的复杂相互作用；通过定向调控共生体设计绿色高效的害虫防治策略。

Research advances in symbiotic microorganisms in insects and their functions

Symbiotic microorganisms can account for 1%-10% of insect biomass, includingacteria, fungi, archaea and viruses. Insects and symbiotic microorganisms co-evolve toform holobionts. Symbiotic microorganisms play an important role in the biologicalcharacteristics, diversity formation, ecological adaptability and stress resistance ofinsects. Crop pest insects seriously affect agricultural production. In this article, theresearch advances in the diversity, research methods, and functional mechanisms of insectsymbiotic microorganisms, the interaction between symbiotic microorganisms and theirapplication in pest control since 2000 were reviewed and prospected. With the continuousdevelopment and application of advanced research methods such as molecular microbialecology and metagenomic sequencing, breakthroughs have been made in the research ofsymbiotic microorganisms of agricultural pest insects. It was found that symbioticmicroorganisms mainly affect host insects in the following ways: (1) Synthesis of nutrientsor production of digestive enzymes to promote host growth and development and to expandhost ecological niche; (2) Production of protective metabolites to directly protect thehost against stress or indirectly protect the host by regulating the defense response ofhost plants; and (3) Production of active substances to regulate host propagation, mating,aggregation and movement. The abundance and community composition of insect symbioticmicroorganisms maintain dynamic changes in a certain spatial-temporal range and have animportant impact on host phenotype, which is the result of the benefit trade-off amonghost, environment, and interactive microorganisms. We suggest that future research shouldfocus on clarifying the molecular mechanisms underlying the formation and maintenance ofsymbionts, ascertaining the complex interactions among symbiotic microorganisms, hostinsects, plants, natural enemies and the environment in more spatial-temporal dimensions,and designing green and efficient pest control strategies through targeted regulation ofpest insect symbionts.