|
Study on the mitigation of cadmium stress in rice by cadmium-resistant Bacillus aryabhattai |
Received:July 15, 2020 |
View Full Text View/Add Comment Download reader |
KeyWord:cadmium contamination;rice;Bacillus;plant growth promoting;antioxidant enzyme;bioremediation |
Author Name | Affiliation | E-mail | FAN Mei-yu | College of Life Sciences, Capital Normal University, Beijing 100048, China | | LI Ni | State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha 410125, China | | JIA Yu-tian | College of Life Sciences, Capital Normal University, Beijing 100048, China | | ZHANG Chao | State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha 410125, China | | WANG Wei-ping | State Key Laboratory of Hybrid Rice, Hunan Hybrid Rice Research Center, Changsha 410125, China | 15111034840@126.com | YANG Zhi-wei | College of Life Sciences, Capital Normal University, Beijing 100048, China | yangzw@cnu.edu.cn |
|
Hits: 1973 |
Download times: 2569 |
Abstract: |
In order to explore the efficacy of Bacillus aryabhattai T61 in mitigating cadmium stress on rice, the Cd tolerance, removal rate, and plant growth promotion traits of T61 bacteria were determined using 96-well plate assays, inductively coupled plasma mass spectrometry, and colorimetric methods. A T61-eGFP strain was used to observe the colonization of T61 in rice plants. The T61 inoculum was applied using the dipping root method, to observe its effect of reducing Cd accumulation in rice grains. Results showed that T61 had a maximum Cd2+ tolerance concentration of up to 500 mmol·L-1. The Cd2+ removal rate of T61 was more than 50% after being cultured in liquid medium containing Cd2+ for 24 hours. T61 could synthesize plant growth promoting substances, such as indoleacetic acid(6.2 μg·mL-1)and siderophore(46.6 μmol·L-1), and had the ability to dissolve inorganic phosphate(37.1 μg·mL-1). It was confirmed that T61 could colonize rice roots and shoots. Under field conditions, the application of T61 inoculum could reduce malondialdehyde content and the activities of antioxidant enzymes in rice shoots in the vegetative stage and decrease the Cd content in 728B and NX1B grains by 13.5% and 11.2%, respectively. Therefore, Bacillus aryabhattai T61 is a Cd-tolerant bacterium with plant growth promoting traits, which can alleviate Cd stress in some rice cultivars, and has application prospects in the microbial remediation of Cd-contaminated paddy fields. |
|
|
|