沙蓬(Agriophyllum squarrosum)根际固氮菌群落结构特征  

Dynamic characteristics of diazotrophs community in the rhizosphere of Agriophyllum squarrosum

作　　者：张胜男 杨杉杉 高海燕 张雷[1] 闫德仁[1] 魏一凡 Shengnan Zhang;Shanshan Yang;Haiyan Gao;Lei Zhang;Deren Yan;Yifan Wei(Inner Mongolia Academy of Forestry,Hohhot 010010,China;College of Life Science,Northwest A&F University,Yangling 712100,Shaanxi,China)

机构地区：[1]内蒙古自治区林业科学研究院,内蒙古呼和浩特010010 [2]西北农林科技大学生命科学学院,陕西杨凌712100

出　　处：《中国沙漠》2024年第4期174-183,共10页Journal of Desert Research

基　　金：国家自然科学基金项目(31960284);内蒙古自治区林业科学研究院科研能力提升项目。

摘　　要：为了解固沙先锋植物沙蓬不同发育阶段根际固氮菌群落结构特征,以库布齐沙漠幼苗期、营养生长期、生殖生长期和立枯期沙蓬根际土壤为研究对象,通过高通量测序分析不同发育阶段固氮菌群落组成和多样性,通过冗余分析分析固氮菌群落与土壤养分的相关性。结果表明:β-变形菌纲和广泛固氮氢自养单胞菌属为沙蓬根际的主要固氮菌类群,具有生长迅速和自养的特点,丰度分别为44.30%~90.51%和35.05%~72.89%。沙蓬不同发育阶段根际固氮菌群落具有显著性差异,属水平的差异固氮菌分别为广泛固氮氢自养单胞菌属、斯克尔曼氏菌属和慢生根瘤菌属。营养生长期,与有机质、中性磷酸酶和中性蛋白酶活性呈显著正相关的斯克尔曼氏菌属明显高于幼苗期(2.76倍)、生殖生长期(4.22倍)和立枯期(3.13倍);生殖生长期,与有机质、中性磷酸酶、速效磷和过氧化氢酶活性呈显著负相关的慢生根瘤菌属明显高于幼苗期(3.56倍)和立枯期(8.58倍),在营养生长期未出现。幼苗期和营养生长期参与碳循环的有机质和蔗糖酶活性显著升高,参与氮循环的速效氮、脲酶和中性蛋白酶活性显著升高,生殖生长期根际养分显著下降。综上,沙蓬不同发育阶段根际固氮菌群落具有显著差异,幼苗期和营养生长期的固氮菌以蓄积碳、氮源为主,生殖生长期以消耗养分为主,促进了根际固氮菌营养竞争性演替,为沙地、沙漠固沙先锋植物种群恢复以及沙产业氮肥施用措施提供理论基础。In order to understand the community structure of rhizosphere diazotrophs at different developmental stages of sand-fixing pioneer plant Agriophyllum squarrosum,the rhizosphere soil at seedling stage,vegetative stage,reproductive stage and withering stage in Hobq Desert was taken as the research object.The composition and diversity of diazotrophs community at different developmental stages were analyzed by high-throughput sequencing,and the correlation between diazotrophs community and soil nutrients was analyzed by redundancy.The results showed thatβ-Proteobacteria and Azohydromonas were the main diazotrophs groups in the rhizosphere of A.squarrosum,which have the characteristics of rapid growth and autotroph,with abundance ranging from 44.30%to 90.51%and 35.05%to 72.89%,respectively.There were significant differences in rhizosphere diazotrophs communities at different developmental stages,the different diazotrophs species were Azohydromonas,Skermanella and Bradyrhizobium at genus level.In the vegetative stage,the relative abundance of Skermanella positively correlated with organic matter,neutral phosphatase activities and neutral protease activities was significantly higher than that in seedling stage(2.76 times),reproductive stage(4.22 times)and withering stage(3.13 times).In the reproductive stage,the relative abundance of Bradyrhizobium negatively correlated with organic matter,neutral phosphatase activities,available phosphorus and catalase activities was significantly higher than that in seedling stage(3.56 times)and withering stage(8.58 times),and did not appear in the vegetative stage.Organic matter,sucrase activities involved in carbon cycle and available nitrogen,urease,neutral protease involved in nitrogen cycle were significantly increased at the seedling and the vegetative stages,rhizosphere nutrients decreased significantly during the reproductive stage.In conclusion,the rhizosphere diazotrophs communities of A.squarrosum had significant differences at different developmental stages.Diazotrophs in

关 键 词：沙蓬 发育阶段 固氮菌 演替 酶活性 

分 类 号：Q938[生物学—微生物学]