Open AccessGenetic diversity of bacteria in bioremediation system of iron mine tailing by Robinia pseudoacacia - Ryegrass - Trifolium repens
Author(s) -
Xiaoyu Zhou,
Yihao Liu,
Zuyu Wang,
Wei Xiong,
Xiumei Yu,
Ke Zhao,
Ke Zhang,
Yunfu Gu,
Menggen Ma,
Qiang Chen
Publication year - 2020
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/467/1/012145
Subject(s) - robinia , rhizosphere , tailings , trifolium repens , biology , nitrogen fixation , bioremediation , bacteria , botany , 16s ribosomal rna , phytoremediation , genetic diversity , microorganism , repens , horticulture , soil water , chemistry , population , ecology , genetics , demography , sociology
To exploration the change of microorganism in iron tailing sand restoration, a bioremediation system of iron tailing sand by combination of Robinia pseudoacacia - Ryegrass-Trifolium repens pus soil or bio-matrix flowerpot was designed, the change of bacterial quantity and genetic diversity at different time was determined. The tailings and soil samples C1 (tailings), C2 (tailings adjacent to biologic pot) and C3 ( Robinia pseudoacacia rhizosphere soil), were collected on the 180 th d, 270 th d and the 360 th d. The bacterial quantity was determined, the bacterial strains were isolated and purified, and genetic diversity was studied by BOXA1R-PCR and 16S rDNA sequencing. The results showed that along the restoration time increasing, the number of bacteria in C2 and C3 increased from 4.81×10 5 cfu·g −1 and 11.82×10 5 cfu·g −1 to 5.99×10 5 cfu·g −1 and 15.67×10 5 cfu·g −1 at 270 th d, then to 8.96×10 5 cfu·g −1 and 21.96×10 5 cfu·g −1 at 360 th d, respectively, while there was little change in C1. From these samples, a total of 32, 46 and 52 bacterial strains were isolated, and the genetic diversity was determined by BOXA1R-PCR, the results showed that there were 7, 9 and 10 BOXA1R groups formed, respectively; phylogenetic analysis of representatives suggested that genus Bacillus were the predominant, and bacteria with biological nitrogen fixation ability, distributed in Rhizobium, Ensifer, Azotobacter , etc. were founded during the iron tailing sand bioremediation. The results suggests that bio-matrix flowerpot combining Robinia pseudoacacia - Ryegrass - Trifolium repens cultivar can increase the bacterial quantity and genetic diversity in iron tailing sand significantly, and probably has a good application potential for tailings restoration.