Effect of AM Fungi Inoculation on Litter Bacterial Community Characteristics under Heavy Metal Stress.

Yu Wang,Xiaoxia Liang,Tingyan Guo,Tong Jia

doi:10.3390/microorganisms10020206

Yu Wang, Xiaoxia Liang + Show 2 more

Open Access

https://doi.org/10.3390/microorganisms10020206

Copy DOI

Journal: Microorganisms	Publication Date: Jan 19, 2022
Citations: 6	License type: CC BY 4.0

Affiliation: Shanxi University

Abstract

Because microorganisms are the primary driving force behind litter decomposition, they play an important role in maintaining ecosystem material and chemical cycling. Arbuscular mycorrhizal (AM) fungi can improve host plant tolerance to various environmental stressors, making their application in mining area remediation important. In this study, litter from the dominant plant species (Imperata cylindrica) in a copper tailings mining area was selected as the experimental material. We conducted a greenhouse-based heavy metal stress experiment to investigate how AM fungi affect litter microbial community characteristics and key ecological factors. Results showed that AM fungi species, heavy metal treatments, and their combined interaction had significant impacts on litter pH. Additionally, enzyme activities in litter were significantly affected by interactions between AM fungi species and heavy metal contaminates. Ralstonia was significantly positively correlated to lead (Pb) content, indicating that Ralstonia had a certain tolerance to Pb pollution. Sucrase and urease activity were increased when plants were inoculated with Rhizophagus irregularis under Pb stress. Furthermore, Microbacterium, Brevundimonas, and Pseudonocardia all may play important roles in litter decomposition, while a certain tolerance was observed in Kushneria and Roseivivax to heavy metal pollution when plants were inoculated with Glomus mosseae. Results showed that AM fungi affected litter bacterial community structure and function by influencing plant litter properties. By exploring interactions between AM fungi and bacterial communities in plant litter under heavy metal stress, we will better understand associative processes that promote the cycling of soil organic matter and nutrients contaminated by non-ferrous metal tailings.

Highlights

Published: 19 January 2022Litter is the link that connects plants and soil [1]
Litter pH increased under the GM treatment in the absence of heavy metal stress, while litter pH decreased under the RI treatment
Previous studies have found that arbuscular mycorrhizas (AM) fungi had no significant effect on antecedent aboveground litter content for Leymus chinensis and M. sativa, while no significant difference was observed in litter decomposition rates [5]

Summary

Introduction

Its decomposition encourages the development of soil organic matter. It plays an important role in the formation of soil carbon (C) pools and the release of mineral elements as well as various types of nutrients. The role that litter decomposition plays is important for regulating plant growth processes, while affecting the net productivity of terrestrial ecosystems [2]. As a type of symbiotic (mycorrhizal) microorganism, arbuscular mycorrhizas (AM) species are directly associated with soil and plant root systems and play critical roles in the host plant litter decomposition process. Two AM fungi species (Glomus mosseae and Glomus claroideum) have been shown to significantly reduce decomposition coefficients in the root litter of Leymus chinensis [5]

Methods

Results

Discussion

Conclusion