宁夏荒漠草原典型灌丛根际土壤细菌群落结构与功能  

Analysis of bacterial community structure and function in rhizosphere soil of typical shrub in desert steppe of Ningxia

作　　者：姚佳妮 代金霞 刘爽 张钧杰 胡明珠 YAO Jiani;DAI Jinxia;LIU Shuang;ZHANG JunJie;HU Mingzhu(College of Life Sciences,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学生命科学学院,银川750021

出　　处：《生态学报》2024年第20期9285-9299,共15页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(32160023,31760027);宁夏自然科学基金项目(2023AAC03062)。

摘　　要：土壤微生物群落组成和功能特性对维持生态系统功能至关重要,明确荒漠土壤微生物群落结构、群落功能及其环境响应特征对维持生态系统稳定性及多样性保护具有重要意义。对宁夏白芨滩荒漠草原内柠条(Caragana spp.)、沙冬青(Ammopiptanthus mongolicus)、毛刺(Caragana tibetica)和猫头刺(Oxytropis aciphylla)4种典型豆科灌丛不同发育期根际土壤样品进行了16S rRNA和宏基因组高通量测序,研究了荒漠草原生境下豆科灌丛根际土壤细菌群落结构与功能和根际碳、氮循环特征,并分析了影响微生物群落的关键环境因子。结果表明:4种灌丛果实期根际土壤细菌群落的丰富度和多样性较高,而不同灌丛之间无显著差异。放线菌门、变形菌门和酸杆菌门等优势类群相对丰度在灌丛间有差异但差异不显著。其中放线菌门(32.98%—44.53%)是根际最优势门类,其次为变形菌门、酸杆菌门和绿弯菌门;共有322个核心细菌属,多样性较为丰富。节杆菌属、红色杆菌属和微枝杆菌属为可定义的优势属。根际土壤微生物功能途径因灌丛种类和发育期的不同而有差异。蛋白质直系同源簇数据库(COG)和京都基因与基因组百科全书(KEGG)功能注释表明,4种灌丛根际土壤中仍存在大量未知的功能类群有待挖掘,参与能量生成和转化、碳水化合物转运代谢和信号转导等功能群落在4种土壤间具有显著差异。在KEGG level 1水平下与代谢相关的功能类群丰度最高,平均占比73.05%。碳、氮循环特征分析表明,碳固定中还原性柠檬酸循环途径相关基因丰度较高,氮循环中有机氮代谢途径相关基因丰度较高。柠条根际土壤微生物参与碳、氮固定的基因丰度较其它3种土壤高。冗余分析(RDA)表明,放线菌门、厚壁菌门与土壤全氮(TN)、铵态氮(NH+4-N)、总磷(TP)和有效磷(AP),变形菌门与pH显著正相关,酸杆菌门与AP、速效钾(AK)和pH显�The composition and functional characteristics of soil microbial community are crucial to the maintenance of ecosystem functions.It is of great significance to identify the structure,community functions and environmental response characteristics of desert soil microbial community for the maintenance of ecosystem stability and diversity protection.In this paper,16S rRNA and Metagenomics high-throughput sequencing were performed on rhizosphere soil samples of four typical legume shrubs(Caragana spp.,Ammopiptanthus mongolicus,Caragana tibetica and Oxytropis aciphylla)from the Baijitan desert steppe in Ningxia.The structure and functional characteristics of the rhizosphere soil bacterial communities and the rhizosphere carbon and nitrogen cycles of the four typical legume shrubs in desert habitats were investigated,and the key environmental factors affecting the microbial communities were also analysed.The results showed that:the richness and diversity of rhizosphere soil bacterial communities were high in the fruit period of the four shrublands,and there was no significant difference among different shrublands.The relative abundances of dominant groups such as Actinobacteria,Proteobacteria and Acidobacteria were different but the differences were not significant.The most dominant bacterial phylum of rhizosphere at different development periods of the four legume shrubs was Actinobacteria(32.98%—44.53%),followed by Proteobacteria,Acidobacteria and Chloroflexi;there were 322 core bacterial genus and the diversity was relatively rich.Arthrobacter,Rubrobacter and Microvirga were the dominant genus that could be defined.Functional annotation of the metagenomics data showed that rhizosphere microbial functional pathways at different development periods of the four legume shrubs differed according to the shrub species and development period.Functional annotations of COG(Cluster of Orthologous Groups of Proteins)and KEGG(Kyoto Encyclopedia of Genes and Genomes)indicated that there were still a large number of unknown func

关 键 词：豆科灌丛 16S rRNA测序 宏基因组测序 根际土壤细菌多样性 碳循环基因 氮循环基因 

分 类 号：S812.2[农业科学—草业科学]