Li Y, Yu X, Cui Y, Tu W, Shen T, Yan M, Wei Y, Chen X, Wang Q, Chen Q, Gu Y, Zhao K, Xiang Q, Zou L, Ma M. The potential of cadmium ion-immobilized Rhizobium pusense KG2 to prevent soybean root from absorbing cadmium in cadmium-contaminated soil.
J Appl Microbiol 2019;
126:919-930. [PMID:
30489679 DOI:
10.1111/jam.14165]
[Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 10/12/2018] [Accepted: 11/19/2018] [Indexed: 11/28/2022]
Abstract
AIMS
Because the effect of Cd2+ -immobilized microbe on Cd uptake of plants in Cd-contaminated soil remains underexplored, this study focuses on the effect of Cd2+ -immobilized rhizobia on Cd uptake of soybean.
METHODS AND RESULTS
Strain KG2 from soybean nodule was identified as Rhizobium pusense KG2 by phylogenetic analysis. Rhizobium pusense KG2 showed the 120 mg l-1 of minimal lethal concentration for Cd2+ . In 50 and 100 mg l-1 of Cd2+ liquid, approximately 2 × 1010 cells removed 56·71 and 22·11% of Cd2+ , respectively. In pot soil containing 50 and 100 mg kg-1 of Cd2+ , strain KG2 caused a 45·9 and 35·3% decrease in soybean root Cd content, respectively. Meanwhile, KG2 improved the root and shoot length, nitrogen content and biomass of soybean plants and superoxide dismutase activity.
CONCLUSIONS
The Cd2+ -immobilized rhizobia could inhibit soybean plants to absorb Cd2+ from soil, promote plant growth and improve plant's tolerance against Cd. This study is the first time to report that R. pusense is an effective nodulating rhizobium of legume.
SIGNIFICANCE AND IMPACT OF THE STUDY
Some Cd2+ -immobilized microbe lowering Cd uptake of plant and promoting plant growth should be considered as an effective strategy for producing safety crops in the Cd-contaminated agricultural soil.
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