Pongamia pinnata inoculated with Bradyrhizobium liaoningense PZHK1 shows potential for phytoremediation of mine tailings

详细信息    查看全文

• 作者：Xiumei Yu ; Yangxin Li ; Yanmei Li ; Chaohua Xu…
• 关键词：Phytoremediation ; Pongamia pinnata ; Bradyrhizobium ; Iron–vanadium–titanium oxide mine tailings ; Nickel soil
• 刊名：Applied Microbiology and Biotechnology
• 出版年：2017
• 出版时间：February 2017
• 年：2017
• 卷：101
• 期：4
• 页码：1739-1751
• 全文大小：
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Microbiology; Microbial Genetics and Genomics; Biotechnology;
• 出版者：Springer Berlin Heidelberg
• ISSN：1432-0614
• 卷排序：101

文摘

Mine tailings contain high concentrations of metal contaminants and only little nutrients, making the tailings barren for decades after the mining has been terminated. Effective phytoremediation of mine tailings calls for deep-rooted, metal accumulating, and soil fertility increasing plants with tolerance against harsh environmental conditions. We assessed the potential of the biofuel leguminous tree Pongamia pinnata inoculated with plant growth promoting rhizobia to remediate iron–vanadium–titanium oxide (V–Ti magnetite) mine tailing soil by pot experiment and in situ remediation test. A metal tolerant rhizobia strain PZHK1 was isolated from the tailing soil and identified as Bradyrhizobium liaoningense by phylogenetic analysis. Inoculation with PZHK1 increased the growth of P. pinnata both in V–Ti magnetite mine tailings and in Ni-contaminated soil. Furthermore, inoculation increased the metal accumulation capacity and superoxide dismutase activity of P. pinnata. The concentrations of Ni accumulated by inoculated plants were higher than the hyperaccumulator threshold. Inoculated P. pinnata accumulated high concentration of Fe, far exceeding the upper limit (1000 mg kg−1) of Fe in plant tissue. In summary, P. pinnata–B. liaoningense PZHK1 symbiosis showed potential to be applied as an effective phytoremediation technology for mine tailings and to produce biofuel feedstock on the marginal land.