大豆不同生育期根际土壤细菌群落结构的变化

为了解大豆根际细菌群落结构多样性及根际细菌群落结构的变化,该研究以大豆苗期和成熟期的根际土壤为材料,采用Illumina高通量测序技术测定细菌16S rRNA V3+V4区序列,探究大豆不同生育期根际土壤细菌群落结构的变化。对原始数据进行拼接、过滤、去除嵌合体序列和聚类分析等数据处理,并对OTU进行分类学注释。在此基础上运用ANOVA分析物种组成变化,Alpha多样性指数研究细菌多样性变化。结果表明:细菌丰富度和多样性在不同生育期有显著变化,其中成熟期土壤中的细菌丰富度和多样性指数均明显高于苗期; 变形菌、放线菌、酸杆菌是大豆根际的优势菌门,其含量在不同生育期也有显著变化; 假诺卡氏菌属、糖丝菌属、鞘氨醇单胞菌属是大豆根际的优势菌属,这些菌属中的部分菌群属于根际促生菌,具有潜在的促生效应。这些结果证实大豆的生育期对根际土壤细菌群落结构有重要影响。

Changes of bacterial flora structure in rhizosphere soil of soybean at different growth stages

Soybean rhizosphere soils at seedling and mature stages were collected in this experiment as the research material, and Illumina high-throughput sequencing technology was used to determine the 16S rDNA V3+V4 region sequence of bacteria, in order to understand the diversity of bacterial community structure and the changes of bacterial community structure in soybean rhizosphere.The original Tags data were used by splicing, filtering, removal of chimeric sequences and cluster analysis of data processing, OTU taxonomic annotation. On this basis, the changes of species composition were analyzed by ANOVA method, and the diversity of bacterial composition was also studied by alpha diversity index. The results showed that there was a significant change in the abundance and diversity of bacteria at different growth stages. Diversity index analysis showed that the abundance and diversity at mature stage was significantly higher than seedling stage in soybean rhizosphere soil. Species composition analysis results showed that Proteobacteria, Actinobacteria and Acidobacteria are the dominant rhizosphere bacteria at phylum level and their contents in different growth stages also significantly increased. ANOVA analysis showed that the abundances of Proteobacteria and Acidobacteria were significantly different, but Actinobacteria was not significantly different at different growth stages. Pseudonocardia, Saccharomyces and Sphingomonas were the dominant genra in the rhizosphere of soybean. Some of these genera belonged to plant growth-promoting rhizobcteria and had the potential capacity for promoting growth. These results confirm that the growth period of soybean has an important influence on the bacterial community structure in rhizosphere soil.