AUTHOR=Ju Yawen , Zhong Rui , Christensen Michael J. , Zhang Xingxu 

TITLE=Effects of Epichloë gansuensis Endophyte on the Root and Rhizosphere Soil Bacteria of Achnatherum inebrians Under Different Moisture Conditions

JOURNAL=Frontiers in Microbiology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.00747

DOI=10.3389/fmicb.2020.00747

ISSN=1664-302X

ABSTRACT=<p>This study was conducted to explore effects of the systemic fungal endophyte <italic>Epichloë gansuensis</italic> on root and rhizosphere soil bacterial diversity of <italic>Achnatherum inebrians</italic> host plants growing under different moisture conditions. Soil properties of different treatments were compared using standard techniques. A total of 4371379 16S rRNA gene sequences were obtained and assigned to 5025 operational taxonomic units (OTUs). These OTUs in roots and rhizosphere soil were divided into 13 and 17 phyla, respectively, and the Actinobacteria and Proteobacteria were the most abundant phyla both in roots and rhizosphere soil. Shannon diversity and Chao1 richness index of bacteria in rhizosphere soil was significantly higher than in roots. <italic>E. gansuensis</italic> decreased the Shannon diversity of the root-associated bacterial community, and increased Shannon diversity and Chao1 richness index of the rhizosphere soil bacterial community of <italic>A. inebrians</italic>. Meanwhile, Chao1 richness of the rhizosphere soil bacterial community of <italic>A. inebrians</italic> significantly increased with the increase of the soil moisture level. Structural equation modeling also emphasized that <italic>E. gansuensis</italic> decreased the diversity of the root-associated bacterial community and increased the diversity of the rhizosphere soil bacterial community through decreasing soil available <italic>N</italic>. Additionally, soil moisture increased the diversity of the rhizosphere soil bacterial community through increased soil pH, C/N, and NN, and decreased soil AP. The <italic>E. gansuensis</italic> endophyte and soil moisture effects on root and rhizosphere soil bacterial diversity were likely to be from responses to modifications of the rhizosphere soil properties.</p>