Changes in soil bacterial and fungal communities in response to Bacillus megaterium NCT-2 inoculation in secondary salinized soil

Bin Wang; Shaohua Chu; Xiaorui Liu; Dan Zhang; Xiaotong Chai; Xijia Yang; Yuee Zhi; Yaowei Chi; Pei Zhou

doi:10.7717/peerj.12309

Changes in soil bacterial and fungal communities in response to Bacillus megaterium NCT-2 inoculation in secondary salinized soil

PeerJ. 2021 Oct 12:9:e12309. doi: 10.7717/peerj.12309. eCollection 2021.

Authors

Bin Wang^#^{1

2

3}, Shaohua Chu^#^{1

2

3}, Xiaorui Liu^{1

2

3}, Dan Zhang^{1

2

3}, Xiaotong Chai^{1

2

3}, Xijia Yang^{1

2

3}, Yuee Zhi^{1

2

3}, Yaowei Chi^{1

2

3}, Pei Zhou^{1

2

3}

Affiliations

¹ School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China.
² Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Affairs, Shanghai, China.
³ Bor S. Luh Food Safety Research Center, Shanghai Jiao Tong University, Shanghai, China.

^# Contributed equally.

Abstract

Background: Secondary salinized soil in greenhouses often contains excess nitrate. Inoculation of Bacillus megaterium NCT-2 with nitrate assimilation ability represents an attractive approach for soil remediation. However, the effects of NCT-2 on the structure and function of soil microbial communities have not been explored.

Methods: Greenhouse experiments were carried out to investigate changes in soil properties, Brassica chinensis L. growth, bacterial, and fungal community structure and function in response to NCT-2 inoculation.

Results: The NCT-2 inoculant significantly reduced the nitrate content in B. chinensis and inhibited the rebound of soil nitrate in the later stage. The shifts of bacterial community structure and function by NCT-2 was negligible, and a greater disturbance of soil fungal community structure and function was observed, for example the strong inhibitory effect on ectomycorrhizal fungi. These results indicated that the NCT-2 inoculant likely achieved the remediation effect in secondary salinized soil by shifting fungal community. The present findings add to the current understanding of microbial interactions in response to bacterial inoculation and can be of great significance for the application of NCT-2 inoculants in secondary salinized soil remediation.

Keywords: Bacillus megaterium NCT-2; Ectomycorrhizal fungi; FUNGuild; Microbial community; Nitrate.

Grants and funding

This research was funded by the National Natural Science Foundation of China, grant number 31902105, the China Postdoctoral Science Foundation, grant number 2019M651505, the Shanghai “Science and Technology Innovation Action Plan” Social Development Science and Technology Project, grant number 20dz1204804, and the Young Elite Scientists Sponsorship Program by CAST, grant number 2017QNRC001. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.