Comparative Analyses of Rhizosphere Bacteria Along an Elevational Gradient of Thuja sutchuenensis

You-Wei Zuo; Jia-Hui Zhang; Deng-Hao Ning; Yu-Lian Zeng; Wen-Qiao Li; Chang-Ying Xia; Huan Zhang; Hong-Ping Deng

doi:10.3389/fmicb.2022.881921

Comparative Analyses of Rhizosphere Bacteria Along an Elevational Gradient of Thuja sutchuenensis

Front Microbiol. 2022 May 3:13:881921. doi: 10.3389/fmicb.2022.881921. eCollection 2022.

Authors

You-Wei Zuo^{1

2}, Jia-Hui Zhang^{1

2}, Deng-Hao Ning^{1

2}, Yu-Lian Zeng^{1

2}, Wen-Qiao Li^{1

2}, Chang-Ying Xia^{1

2}, Huan Zhang^{1

2}, Hong-Ping Deng^{1

2

3}

Affiliations

¹ Center for Biodiversity Conservation and Utilization, School of Life Sciences, Southwest University, Chongqing, China.
² Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, School of Life Sciences, Institute of Resources Botany, Southwest University, Chongqing, China.
³ Chongqing Academy of Science and Technology, Low Carbon and Ecological Environment Protection Research Center, Chongqing, China.

Abstract

Thuja sutchuenensis Franch. is an endangered species in southwestern China, primarily distributed in 800-2,100 m of inaccessible mountainous areas. Rhizosphere soil physicochemical properties and bacterial communities play an essential role in managing plant growth and survival. Nonetheless, the study investigating rhizosphere soil properties and bacterial communities of T. sutchuenensis is limited. The present study investigated soil properties, including soil pH, organic matter, water content, nitrogen, phosphorus, and potassium contents, and bacterial communities in nearly all extant T. sutchuenensis populations at five elevational gradients. Our results demonstrated that the increase in elevation decreased rhizosphere and bulk soil phosphorus content but increased potassium content. In addition, the elevational gradient was the dominant driver for the community composition differentiation of soil bacterial community. Proteobacteria and Acidobacteria were the dominant bacterial phyla distributed in the rhizosphere and bulk soils. Co-occurrence network analysis identified key genera, including Bradyrhizobium, Acidicapsa, Catenulispora, and Singulisphaera, that displayed densely connected interactions with many genera in the rhizosphere soil. The dominant KEGG functional pathways of the rhizosphere bacteria included ABC transporters, butanoate metabolism, and methane metabolism. Further correlation analysis found that soil phosphorus and potassium were the dominant drivers for the diversity of soil bacteria, which were distinctively contributed to the phylum of Planctomycetes and the genera of Blastopirellula, Planctomycetes, and Singulisphaera. Collectively, this comprehensive study generated multi-dimensional perspectives for understanding the soil bacterial community structures of T. sutchuenensis, and provided valuable findings for species conservation at large-scale views.

Keywords: Thuja sutchuenensis; bacterial community diversity; elevational variation; rhizosphere; soil properties.