遗传 ›› 2021, Vol. 43 ›› Issue (5): 487-500.doi: 10.16288/j.yczz.20-409

• 研究报告 • 上一篇    下一篇

酸铝胁迫土壤中耐铝大豆根际不同部位细菌群落结构、功能及其对促生菌富集作用的研究

文钟灵, 杨旻恺, 陈星雨, 郝晨宇, 任然, 储淑娟, 韩洪苇, 林红燕, 陆桂华, 戚金亮, 杨永华()   

  1. 南京大学植物分子生物学研究所,医药生物技术国家重点实验室,生命科学学院,南京 210023
  • 收稿日期:2020-11-30 修回日期:2020-12-29 出版日期:2021-05-20 发布日期:2021-01-27
  • 通讯作者: 杨永华 E-mail:yangyh@nju.edu.cn
  • 作者简介:文钟灵,博士研究生,研究方向:土壤分子微生物学。E-mail: DG1730028@smail.nju.edu.cn|杨旻恺,博士研究生,研究方向:土壤分子微生物学。E-mail: minkaiyang@163.com;

    文钟灵和杨旻恺并列第一作者
  • 基金资助:
    国家重点研发计划项目编号(2016YFD0101005);国家自然科学基金项目编号(31870495, 31372140);教育部创新团队项目(编号)资助(IRT_14R27)

Bacterial composition, function and the enrichment of plant growth promoting rhizobacteria (PGPR) in differential rhizosphere compartments of Al-tolerant soybean in acidic soil

Zhongling Wen, Minkai Yang, Xingyu Chen, Chenyu Hao, Ran Ren, Shujuan Chu, Hongwei Han, Hongyan Lin, Guihua Lu, Jinliang Qi, Yonghua Yang()   

  1. Institute for Plant Molecular Biology, State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210023, China
  • Received:2020-11-30 Revised:2020-12-29 Online:2021-05-20 Published:2021-01-27
  • Contact: Yang Yonghua E-mail:yangyh@nju.edu.cn
  • Supported by:
    Supported by the National Key Research and Development Program of China No(2016YFD0101005);the National Natural Science Foundation of China Nos(31870495, 31372140);the Program for Changjiang Scholars and Innovative Research Team in University from the Ministry of Education of China No(IRT_14R27)

摘要:

针对酸性土壤中影响作物生产的主要限制因子(pH及其铝毒),选用耐酸铝且具有固氮能力的豆科作物是改良该类土壤、促进农业生产的有效措施之一,至于其所关联的根际微生物是否起到相应的促进作用,一直为国内外学者所关注和探究。为此,本研究以铝耐受型大豆品种基因型(BX10)和铝敏感型大豆品种基因型(BD2)为材料,以酸性红壤为生长介质,采样部位按照土层到根系的距离由远到近的顺序划分为:根外对照土(bulk soil, BS)、两侧根际土(rhizospheric soil at two sides, SRH)、刷后根际土(rhizospheric soil after brush, BRH)和冲洗后的根际土(rhizospheric soil after wash, WRH)。利用Illumina MiSeq对16S rRNA基因扩增产物的高变区V4进行高通量测序,研究了不同耐铝基因型大豆根际细菌群落的结构、功能与分子遗传多样性的差异性作用。结果表明,各处理间大豆根际细菌群落的alpha多样性无显著性差异,beta多样性差异也均不显著。PCA和PCoA分析可见BRH和WRH部位的物种组成较为一致,而BS和SRH部位具有相似的物种组成,说明植物生长主要影响根际的BRH及WRH部位的微生物,对SRH影响较小。对各分类水平物种组成和丰度进行比较,门分类水平三元图表明两个基因型大豆均在WRH部位富集蓝细菌门(Cyanobacteria)细菌;统计分析表明铝耐受型大豆(BX10)根部对于增强植物抗逆性的植物根际促生菌(plant growth promoting rhizobacteria, PGPR)有富集作用,这些富集的细菌包括蓝细菌门、拟杆菌门(Bacteroidetes)和变形菌门(Proteobacteria)等,以及部分与固氮和耐铝的功能相关的属种。另对同一个基因型大豆不同采样部位间进行比较分析,结果显示土壤不同采样部位可以选择性富集不同的PGPR物种。此外,16S rDNA的同源蛋白簇(clusters of orthologous groups of proteins, COG)功能预测分析的结果表明,多个COG包括COG0347、COG1348、COG1433、COG2710、COG3870、COG4656、COG5420、COG5456和COG5554均可能与固氮直接相关;BD2相比于BX10,结果显示在BRH和WRH部位似乎均更易富集固氮直接相关的COG,其可能的原因尚待进一步研究。

关键词: 酸性土壤, 耐铝大豆, 根际, 细菌群落, 植物根际促生菌

Abstract:

Low pH with aluminum (Al) toxicity are the main limiting factors affecting crop production in acidic soil. Selection of legume crops with acid tolerance and nitrogen-fixation ability should be one of the effective measures to improve soil quality and promote agricultural production. The role of the rhizosphere microorganisms in this process has raised concerns among the research community. In this study, BX10 (Al-tolerant soybean) and BD2 (Al-sensitive soybean) were selected as plant materials. Acidic soil was used as growth medium. The soil layers from the outside to the inside of the root are bulk soil (BS), rhizosphere soil at two sides (SRH), rhizosphere soil after brushing (BRH) and rhizosphere soil after washing (WRH), respectively. High-throughput sequencing of 16S rDNA amplicons of the V4 region using the Illumina MiSeq platform was performed to compare the differences of structure, function and molecular genetic diversity of rhizosphere bacterial community of different genotypes of soybean. The results showed that there was no significant difference in alpha diversity and beta diversity in rhizosphere bacterial community among the treatments. PCA and PCoA analysis showed that BRH and WRH had similar species composition, while BS and SRH also had similar species composition, which indicated that plant mainly affected the rhizosphere bacterial community on sampling compartments BRH and WRH. The composition and abundance of rhizosphere bacterial community among the treatments were then compared at different taxonomic levels. The ternary diagram of phylum level showed that Cyanobacteria were enriched in WRH. Statistical analysis showed that the roots of Al-tolerant soybean BX10 had an enrichment effect on plant growth promoting rhizobacteria (PGPR), which included Cyanobacteria, Bacteroides, Proteobacteria and some genera and species related to the function of nitrogen fixation and aluminum tolerance. The rhizosphere bacterial community from different sampling compartments of the same genotype soybean also were selectively enriched in different PGPR. In addition, the functional prediction analysis showed that there was no significant difference in the classification and abundance of COG (clusters of orthologous groups of proteins) function among different treatments. Several COGs might be directly related to nitrogen fixation, including COG0347, COG1348, COG1433, COG2710, COG3870, COG4656, COG5420, COG5456 and COG5554. Al-sensitive soybean BD2 was more likely to be enriched in these COGs than BX10 in BRH and WRH, and the possible reason remains to be further investigated in the future.

Key words: acidic soil, aluminum-tolerant soybean, rhizosphere, bacterial community, PGPR