Adaptation of bacterial community in maize rhizosphere for enhancing dissipation of phthalic acid esters in agricultural soil

• Published in: Journal of hazardous materials Vol. 444; no. Pt A; p. 130292
• Main Authors: Huang, Yu-Hong, Yang, Yu-Jie, Wu, Xiaolian, Zhu, Cui-Lan, Lü, Huixiong, Zhao, Hai-Ming, Xiang, Lei, Li, Hui, Mo, Ce-Hui, Li, Yan-Wen, Cai, Quan-Ying, Li, Qing X.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.02.2023
• Subjects: agricultural soils; bacterial communities; biodegradation; Biodegradation, Environmental; corn; Diethylhexyl Phthalate; Keystone species; Lysobacter; metagenomics; Microbial interaction; Microbiome; Organic pollutant; phthalates; phthalic acid; pollution; quantitative polymerase chain reaction; Rhizobium; Rhizosphere; Rhizospheric degradation; Soil; Sphingomonadaceae; Sphingomonas; Zea mays; Keystone species; Microbial interaction; Organic pollutant; Rhizospheric degradation; Microbiome
• ISSN: 0304-3894; 1873-3336; 1873-3336
• DOI: 10.1016/j.jhazmat.2022.130292

Rhizospheric degradation is a green and in situ strategy to accelerate dissipation of organic pollutants in soils. However, the mechanism on microbial degradation of phthalic acid esters (PAEs) in rhizosphere is still unclear. Here, the bacterial community and function genes in bulk and rhizospheric soils of maize (Zea mays L.) exposed to gradient concentrations of di-(2-ethylhexyl) phthalate (DEHP) were analyzed with 16 S rRNA, metagenomic sequencing and quantitative PCR (qPCR). Maize rhizosphere significantly increased the dissipation of DEHP by 4.02–11.5% in comparison with bulk soils. Bacterial community in rhizosphere exhibited more intensive response and shaped its beneficial structure and functions to DEHP stress than that in bulk soils. Both rhizospheric and pollution effects enriched more PAE-degrading bacteria (e.g., Bacillus and Rhizobium) and function genes in rhizosphere than in bulk soil, which played important roles in degradation of PAEs in rhizosphere. The PAE-degrading bacteria (including genera Sphingomonas, Sphingopyxis and Lysobacter) identified as keystone species participated in DEHP biodegradation. Identification of PAE intermediates and metagenomic reconstruction of PAE degradation pathways demonstrated that PAE-degrading bacteria degraded PAEs through cooperation with PAE-degrading and non-PAE-degrading bacteria. This study provides a comprehensive knowledge for the microbial mechanism on the superior dissipation of PAEs in rhizosphere. [Display omitted] •Rhizosphere and pollution enriched PAE-degrading bacteria and genes.•Enriched PAE-degrading bacteria and genes enhanced rhizosphere degradation.•Keystone species of bacterial community participated in PAE biodegradation.•Metagenome reveals the microbial mechanism of PAE rhizosphere degradation.