基于宏基因组测序解析长刺蒺藜草入侵对根际土壤氮循环的影响  

Effects of spiny burr grass Cenchrus longispinus invasion on rhizosphere nitrogen cycle based on metagenome sequencing

作　　者：高金会 张国良[1] 付卫东[1] 马涛 袁至立 宋振[1] Gao Jinhui;Zhang Guoliang;Fu Weidong;Ma Tao;Yuan Zhili;Song Zhen(Institute of Environment and Sustainable Development in Agriculture,Chinese Academy of Agricultural Sciences,Beijing 100081,China)

机构地区：[1]中国农业科学院农业环境与可持续发展研究所,北京100081

出　　处：《植物保护学报》2022年第5期1349-1357,共9页Journal of Plant Protection

基　　金：国家自然科学基金面上项目(41977203);国家重点研发计划(2021YFD1400300)。

摘　　要：为揭示外来入侵植物长刺蒺藜草Cenchrus longispinus对氮素高效利用的微生态机制,利用宏基因组测序技术分析长刺蒺藜草、狗尾草Setaria viridis、披碱草Elymus dahuricus三种杂草根际土壤及对照中参与氮循环的微生物类群及功能基因差异。结果显示,长刺蒺藜草入侵显著增加了根际土壤中全氮和硝态氮含量,显著降低了土壤水溶性氮含量;长刺蒺藜草根际土壤中链霉菌属Streptomyces、红色杆菌属Rubrobacter、硝化螺旋菌属Nitrospira及类诺卡氏菌属Nocardioides微生物丰度与其他3个处理之间差异显著,并与根际土壤中硝态氮含量显著相关;长刺蒺藜草根际土壤中微生物的氮代谢功能基因nasB和nifK丰度与对照之间差异显著,且与根际土壤中硝态氮含量显著相关。推测长刺蒺藜草入侵通过增加根际土壤中链霉菌属、红色杆菌属和类诺卡氏菌属微生物丰度影响根际土壤的氮代谢过程,通过减少nasA基因丰度降低硝酸盐同化速率,其根际土壤有少量nifK固氮基因,表明其有一定的固氮能力。Exploring the effect of spiny burr grass Cenchrus longispinus invasion on the rhizosphere nitrogen cycle from the perspective of soil microecology will help to reveal its invasion mechanism. In this study, microbial groups and functional genes involved in nitrogen cycle in rhizosphere of C. longispinus, Setaria viridis, Elymus dahuricus, and control were compared and analyzed by using metagenome sequencing technology. The results showed that the invasion of C. longispinus significantly increased the content of total nitrogen and nitrate nitrogen in rhizosphere, and significantly reduced the content of water-soluble nitrogen in soil. The abundance of Streptomyces, Rubrobacter, Nitrospira and Nocardioides of C. longispinus rhizosphere differed significantly from those of other treatments, and had a significant correlation with NO-N. The nitrogen metabolism functional genes nasB and nifK obtained from rhizosphere of C. longispinus were significantly different from control, and had a significant correlation with NO-N. The invasion of C. longispinus affected the nitrogen metabolism process of rhizosphere by increasing the abundance of Streptomyces, Rubrobacter, and Nocardioides, and reducing nitrate assimilation rate by reducing nasA gene abundance. There are a few nifK genes in the rhizosphere tissue of C. longispinus, which showed a certain nitrogen fixing ability.

关 键 词：入侵植物 长刺蒺藜草 宏基因组测序 根际微生物 氮代谢 

分 类 号：S451[农业科学—植物保护]