Evaluation of the cadmium phytoextraction potential of tobacco (Nicotiana tabacum) and rhizosphere micro-characteristics under different cadmium levels. (January 2022)

• Record Type: Journal Article
• Authors: Li, Xuanzhen; Li, Yilun; Zhu, Xiuhong; Gui, Xin; Ma, Chuang; Peng, Wanxi; Li, Yongsheng; Zhang, Yanyan; Huang, Wuxing; Hua, Dangling; Jia, Shengyong; Wu, Mingzuo
• Is Part Of: Chemosphere. Volume 286:Part 2(2022)
• Publication Date: 2022-01
• Subjects: Cd phytoremediation -- Acidification -- Rhizobacteria -- Bioaccumulation -- Microbial community structure; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2021.131714
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: In this study, a field-scale and pot experiment were performed to evaluate the remedial efficiency of Cd contaminated soil by tobacco and explore rhizosphere micro-characteristics under different cadmium levels, respectively. The results indicated that tobacco could remove 12.9 % of Cd from soil within a short growing period of 80 d. The pot experiment revealed that tobacco could tolerate soil Cd concentrations up to 5.8 mg kg −1 and bioaccumulate 68.1 and 40.8 mg kg −1 Cd in shoots and roots, respectively. The high Cd bioaccumulation in tobacco might be attributed to strong acidification in the rhizosphere soil and the increase in Cd bioavailability. Rhizobacteria did not appear to be involved in Cd mobilization. In contrast, tobacco tended to enrich sulfate-reducing bacteria (such as Desulfarculaceae) under high Cd treatment (5.8 mg kg −1 ) but enrich plant growth-promoting bacteria (such as Bacillus, Dyadobacter, Virgibacillus and Lysobacter ) to improve growth under low Cd treatment (0.2 mg kg −1 ), suggesting that tobacco employed different microbes for responding to Cd stress. Our results demonstrate the advantages of using tobacco for bioremediating Cd contaminated soil and clarify the rhizosphere mechanisms underlying Cd mobilization and tolerance. Graphical abstract: Image 1 Highlights: Tobacco achieved a high Cd removal rate in a short period under field conditions. Tobacco has high biomass and a high Cd bioaccumulation ability. Tobacco mobilized Cd mainly by acidifying rhizosphere soil. Tobacco tended to enrich plant growth-promoting bacteria under low Cd. High Cd induced tobacco to enrich sulfate-reducing bacteria.