Pseudomonas sp. TCd-1 significantly alters the rhizosphere bacterial community of rice in Cd contaminated paddy field. (March 2022)

• Record Type: Journal Article
• Authors: Qian, Xin; Lü, Qixin; He, Xiaosan; Wang, Yujie; Li, Hanzhou; Xiao, Qingtie; Zheng, Xinyu; Lin, Ruiyu
• Is Part Of: Chemosphere. Volume 290(2022)
• Publication Date: 2022-03
• Subjects: Heavy metal -- Cadmium stress -- Rice crop -- Rhizosphere microbiome -- Pseudomonas; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.133257
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Cadmium (Cd) pollution of paddy soils is one of the main concerns causing food security and environmental problems. Microbial bioremediation is an effective and eco-friendly measure that uses microbes to reduce Cd accumulation in crops. Additionally, rhizosphere bacterial communities also act essential roles in crop tolerance of heavy metals. However, the effects of inoculations with Cd resistant bacteria on crop rhizosphere bacterial communities under Cd exposure are largely unknown. In this study, we used high-throughput 16S rRNA gene sequencing technologies to explore the community structure and co-occurrence network of the rhizosphere bacterial communities associated with the rice crop under different Cd treatments and the application of Cd-tolerant strain Pseudomonas sp. TCd-1. We found that the strain TCd-1 both significantly reduced the rhizobacterial alpha diversity and changed the beta diversity. PERMANOVA and NMDS analysis showed that Cd stress and TCd-1 strain could act as strong environmental filters resulting in observable differentiation of rhizobacterial community composition among different groups. In addition, RDA results indicated that the rhizosphere pH, root Cd content, catalase (CAT), urease (URE), gibberellic acid (GA3) exert significant association with rhizosphere bacterial assembly. PICRUSt analysis revealed that the TCd-1 strain improved the metabolic capacity of rhizosphere bacteria under Cd stress. Furthermore, co-occurrence network topological features and keystone taxa also varied among different groups. This study could provide necessary insights into developing an efficient bioremediation and safe production of rice crops in Cd contaminated paddy fields with the application of Pseudomonas sp. TCd-1 strain, as well as advance our understanding of the principles of rhizosphere bacterial community assembly under Cd stress. Graphical abstract: Image 1 Highlights: Pseudomonas sp. TCd-1 altered the rhizosphere bacterial diversity and community composition. The pH, root Cd content CAT, URE, GA3 significantly affected the rhizosphere bacterial assemblage. Strain TCd-1 changed the rhizobacterial microbiome potential function and co-occurrence pattern.