Improvement of cadmium-contaminated soil phytoremediation by Centella asiatica L. through bioaugmentation of Enterobacter sp. FM-1
YU Fang-ming1,2,3, YU Qiu-ping2, LIU Ke-hui3,4, WANG Yang2, ZHOU Zhen-ming1,2,3, CHEN Chao-shu1,2,3, LI Yi1,2,3
1. Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection, Ministry of Education, Guilin 541004, China;
2. College of Environment and Resource, Guangxi Normal University, Guilin 541004, China;
3. Key Laboratory of Karst Ecology and Environment Change of Guangxi Department of Education, Guangxi Normal University, Guilin 541004, China;
4. College of Life Science, Guangxi Normal University, Guilin 541004, China
This study analyzed the bacteria tolerance to cadmium and plant growth-promoting substances produced by Enterobacter sp. FM-1. Also, examined the potential of Enterobacter sp. FM-1 to assist in cadmium accumulation for Centella asiatica L. and pH value in rhizosphere soil. The results indicated that Enterobacter sp. FM-1had a relatively high cadmium tolerance. Also, the results showed that indole-3-acetic acid, siderophore parameter (A/Ar) and soluble phosphate ability produced by Enterobacter sp. FM-1 were (72.85±0.62) mg/L, 0.21±0.01 and (143.33±2.13) mg/L, respectively, which indicated that bacteria had an excellent plant growth-promoting ability. Meanwhile, inoculation with Enterobacter sp. FM-1 in the four types of cadmium-contaminated soils which were collected in Siding lead-zinc mining area, increased the accumulation of cadmium in both two types of C. asiatica L. in different degrees. For instance, inoculation with Enterobacter sp. FM-1 in the downstream area soil condition, the cadmium contents in the stems and leaves of mine-type C. asiatica L. increased 87.90%~161.84% and 21.85%~76.42%, respectively. Meanwhile, the cadmium contents in the leaves of non-mine type C. asiatica L. increased 5.84%~35.20%. Hence, inoculation with Enterobacter sp. FM-1 significantly increased the accumulation of cadmium in C. asiatica L. Furthermore, inoculation with Enterobacter sp. FM-1 had influenced the pH value in rhizosphere soil of C. asiatica L. Especially for mine-type C. asiatica L., pH value in rhizosphere soil of downstream area soil condition decreased significantly.
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Wang J, Kim YM, Rhee HS, et al. Bioethanol production from mannitol by a newly isolated bacterium, Enterobacter sp JMP3[J]. Bioresource Technology, 2013,135(10):199-206.
