Table_2_Structure and function of microbiomes in the rhizosphere and endosphere response to temperature and precipitation variation in Inner Mongolia steppes.xlsx

IntroductionOwing to challenges in the study of complex rhizosphere and endophytic microbial communities, the composition and function of such microbial communities in steppe ecosystems remain elusive. Here, we studied the microbial communities of the rhizosphere and endophytic microbes of the dominant plant species across the Inner Mongolian steppes using metagenomic sequencing and investigated their relationships with changes in mean annual temperature (MAT) and mean annual precipitation (MAP).
MethodsMetagenomic sequencing based on Illumina high-throughput sequencing, using the paired end method to construct a small fragment library for sequencing.
ResultsAdaptation of root systems to the environment affected the composition and function of rhizosphere and endophytic microbial communities. However, these communities exhibited distinct community assembly and environmental adaptation patterns. Both rhizosphere and endophytic microbial communities can be divided into two unrelated systems based on their ecological niches. The composition and function of the rhizosphere microbial communities were mainly influenced by MAT, while those of the endophytic microbial communities were mainly influenced by MAP. MAT affected the growth, reproduction, and lipid decomposition of rhizosphere microorganisms, whereas MAP affected reverse transcription and cell wall/membrane/envelope biogenic functions of endophytic microorganisms.
ConclusionOur findings reveal the composition and function of the rhizosphere and endophytic microbial communities in response to changes in MAP and MAT, which has important implications for future biogeography and climate change research.

引言：由于复杂根际与内生微生物群落的研究面临诸多挑战，草原生态系统中此类微生物群落的组成与功能仍尚不明确。本研究借助宏基因组测序技术，针对内蒙古草原各优势植物物种的根际与内生微生物群落展开分析，并探究其与年平均气温（mean annual temperature, MAT）、年平均降水量（mean annual precipitation, MAP）变化的关联关系。
方法：基于Illumina高通量测序平台开展宏基因组测序，采用双端测序法构建小片段文库进行测序。
结果：植物根系对环境的适应性可影响根际与内生微生物群落的组成与功能，但两类群落展现出截然不同的群落组装与环境适应模式。根据生态位特征，根际与内生微生物群落均可划分为两个互不关联的类群。根际微生物群落的组成与功能主要受MAT调控，而内生微生物群落的组成与功能则主要受MAP影响：MAT会作用于根际微生物的生长、繁殖与脂质分解过程，而MAP则影响内生微生物的逆转录及细胞壁/细胞膜/被膜生物发生相关功能。
结论：本研究揭示了内蒙古草原优势植物根际与内生微生物群落的组成及功能对MAT与MAP变化的响应规律，该发现对未来生物地理学及气候变化相关研究具有重要的借鉴意义。