Microbiome structure and function in rhizosphere of Jerusalem artichoke grown in saline land

Abstract

The improvement and development of saline-alkali soils is currently a hot economic and scientific issue, and exploring the correlation between rhizosphere microorganisms of plants growing on saline-alkali soils and their salt tolerance has become the key point of related research. In our study, the community structure of microorganism and various properties of saline soils were characterized in which Jerusalem artichoke grown along a soil salinity gradient. A variety of basic soil properties were measured and the amplicon was performed as well as metagenomic sequencing on coastal saline soils using various techniques (such as RDA analysis and the assembly of genomes) to evaluate microbial functions. In addition, WGCNA (Weighted gene coexpression network analysis) method was used to identify the species related to salt stress and the sequence binning to assemble two enriched putative bacterial genomes. The research showed the cultivation of Jerusalem artichoke on saline soil changed soil physico-chemical and enzymatic properties; most of the rapidly changing as well as the long-term stable properties differed significantly between the rhizosphere and bulk soils. The amplicon and metagenomic sequencing revealed the function and structure of microorganisms varied between the rhizosphere and bulk soils, with greater microbial diversity in the rhizosphere. Catalase activity and the moisture content were the factors with the greatest impact on microorganisms. The putative genomes of two species of microorganisms (belong to Nitrospira and Gemmatimonas) were assembled, identified microbial species that were highly responsive to salt stress and that may play a key role in saline soil, stressed the important role of archaea in microbial communities in response to salt stress. The study provides a comprehensive understanding of the microbial community structure in the rhizosphere of Jerusalem artichoke to enable the improvement and economic development of saline land.

Keywords: Amplicon sequencing; Gene function; Microbial community; Shotgun metagenomics sequencing; Soil properties; Soil salinity.