Claroideoglomus etunicatum affects the structural and functional genes of the rhizosphere microbial community to help maize resist Cd and La stresses. (15th August 2022)

• Record Type: Journal Article
• Authors: Hao, Baihui; Zhang, Zhechao; Bao, Zhihua; Hao, Lijun; Diao, Fengwei; Li, Frank Yonghong; Guo, Wei
• Is Part Of: Environmental pollution. Volume 307(2022)
• Publication Date: 2022-08-15
• Subjects: Arbuscular mycorrhizal fungi -- Cd -- La -- Rhizosphere microbial community -- Functional genes -- Microbial network; AMF Arbuscular mycorrhizal fungi -- HMs heavy metals -- REEs rare earth elements -- Cd Cadmium -- La Lanthanum -- IAA indole-3-acetic acid -- QS quorum sensing -- CE Claroideoglomus etunicatum -- DI deionized -- E_Cd soil mobile proportion of Cd -- E_La soil mobile proportion of La -- AP available P -- AN available N -- SOC soil organic carbon -- NMDS Non-metric multidimensional scaling -- OTUs operational taxonomic units -- KO KEGG Orthology -- P-ATPase P-type ATPase -- MCU Mg2+/Ca2+ uniporter -- MIT CorA metal ion transporter -- DsbD disulfide bond oxidoreductase D -- Nramp metal ion transporter -- CDF cation diffusion facilitator -- ACR3 arsenical resistance-3 -- ACC 1-aminocyclopropane-1-carboxylate; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2022.119559
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Arbuscular mycorrhizal fungi (AMF) and plant rhizosphere microbes reportedly enhance plant tolerance to abiotic stresses and promote plant growth in contaminated soils. The co-contamination of soil by heavy metals (e.g., Cd) and rare earth elements (e.g., La) represents a severe environmental problem. Although the influence of AMF in the phytoremediation of contaminated soils is well documented, the underlying interactive mechanisms between AMF and rhizosphere microbes are still unclear. We conducted a greenhouse pot experiment to evaluate the effects of AMF ( Claroideoglomus etunicatum ) on maize growth, nutrient and metal uptake, rhizosphere microbial community, and functional genes in soils with separate and combined applications of Cd and La. The purpose of this experiment was to explore the mechanism of AMF affecting plant growth and metal uptake via interactions with rhizosphere microbes. We found that C. etunicatum (i) significantly enhanced plant nutritional level and biomass and decreased metal concentration in the co-contaminated soil; (ii) significantly altered the structure of maize rhizosphere bacterial and fungal communities; (iii) strongly enriched the abundance of carbohydrate metabolism genes, ammonia and nitrate production genes, IAA (indole-3-acetic acid) and ACC deaminase (1-aminocyclopropane-1-carboxylate) genes, and slightly altered the abundance of P-related functional genes; (iv) regulated the abundance of microbial quorum sensing system and metal membrane transporter genes, thereby improving the stability and adaptability of the rhizosphere microbial community. This study provides evidence of AMF improving plant growth and resistance to Cd and La stresses by regulating plant rhizosphere microbial communities and aids our understanding of the underlying mechanisms. Graphical abstract: Image 1 Highlights: Separate and combined Cd and La contamination decreased maize growth. AMF promoted maize growth and nutrition uptake in Cd and La contaminated soil. AMF altered the structure of the rhizosphere microbial community. AMF improved nutrient transformation and phytohormone synthesis genes. AMF regulated QS system and HM transport genes, impacting microbial adaptability.