生物技术通报 ›› 2022, Vol. 38 ›› Issue (12): 252-262.doi: 10.13560/j.cnki.biotech.bull.1985.2022-0211

• 研究报告 • 上一篇    下一篇

荒漠植物柠条根际土壤nifH基因荧光定量及固氮菌多样性分析

刘爽(), 姚佳妮, 沈聪, 代金霞()   

  1. 宁夏大学生命科学学院,银川 750021
  • 出版日期:2022-12-26 发布日期:2022-12-29
  • 作者简介:刘爽,女,硕士研究生,研究方向:微生物资源开发与利用;E-mail:1849468755@qq.com
  • 基金资助:
    国家自然科学基金项目(32160023);国家自然科学基金项目(31760027);宁夏自然科学基金项目(2020AAC03104)

Fluorescent Quantitative PCR of nifH Gene and Diversity Analysis of Nitrogen-fixing Bacteria in the Rhizosphere Soil of Caragana spp. of Desert Grassland

LIU Shuang(), YAO Jia-ni, SHEN Cong, DAI Jin-xia()   

  1. School of Life Sciences,Ningxia University,Yinchuan 750021
  • Published:2022-12-26 Online:2022-12-29

摘要:

探索荒漠固沙植物根际土壤nifH基因丰度信息和固氮菌群落结构组成和多样性,可为丰富荒漠区微生物资源库提供基础资料。通过实时荧光定量PCR和高通量测序方法,分析了宁夏荒漠区5个柠条林地根际土壤nifH基因丰度和固氮菌群落结构组成,并结合分离培养方法对柠条根际固氮菌进行筛选和多样性研究。结果表明,5个柠条群落根际土壤nifH基因的拷贝数存在较大的差异,罗山林地(LS)nifH基因拷贝数最高,沙坡头林地(SPT)最低。柠条根际土壤共检测到固氮菌7门12纲26科30属。在科属水平上,沙坡头林地固氮菌群落组成差异较大,未分类的变形杆菌和叶杆菌科分别占25.54%和22.77%,红螺菌科占17.43%,中慢生根瘤菌属是其优势属,相对丰度为22.77%;其余4个林地均以红螺菌科、斯科曼氏球菌属为优势类群,相对丰度分别为23.71%-73.45%和23.19%-71.14%,在罗山林地中占比最高。分离出的固氮菌隶属于15个属,除常见的假单胞菌属、根瘤菌属和肠杆菌属等固氮类群外,还包括勒克氏菌属、金黄杆菌属和寡养单胞菌属等,多样性十分丰富。

关键词: 柠条, nifH基因, 固氮菌群落, 多样性

Abstract:

Exploring the abundance information of nifH gene and the composition and diversity of nitrogen-fixing bacterial community in the rhizosphere soil of the desert sand-fixing plant may provide basic information for enriching the microbial resource pool in desert areas. Real-time quantitative PCR and high-throughput sequencing were applied to analyze the abundance of nifH gene and the community composition of nitrogen-fixing bacteria in the rhizosphere soil of 5 shrublands of Caragana spp. growing in the desert grassland of Ningxia. The method of isolation and culture were to screen nitrogen-fixing bacteria in the rhizosphere soil of Caragana spp. and to study their diversities. The results showed that the copy number of nifH gene in the 5 rhizosphere soil samples were significantly different, the highest in Luoshan(LS)and the lowest in Shapotou(SPT). A total of 7 phyla, 12 classes, 26 families and 30 genera of nitrogen-fixing bacteria were detected in the rhizosphere soil of Caragana spp. At the family and genus level, the community composition of nitrogen-fixing bacteria in Shapotou sample was quite different. Unclassified Proteobacteria and Phyllobacteriaceae accounted for 25.54% and 22.77%, respectively, Rhodospirillaceae accounted for 17.43%, and Mesorhizobium were dominant genus, with a relative abundance of 22.77%; the other four soil samples were dominated by Rhodospirillaceae and Skermanella, with relative abundances of 23.71%-73.45% and 23.19%-71.14%, respectively, and it accounted for the highest proportion in Luoshan sample. The isolated nitrogen-fixing bacteria belong to 15 genera, in addition to the common nitrogen-fixing groups such as Pseudomonas, Rhizobium and Enterobacter, also including Leclercia, Chryseobacterium, Stenotrophomonas, etc., the diversity is abundant.

Key words: Caragana spp., nifH gene, nitrogen-fixing bacteria community, diversity