Phosphate-solubilizing bacteria enhance the growth and lead removal of weed plants (Echinochloa colona)


  • Trung Do Central Institute for Natural Resources and Environmental Studies, Vietnam National University Hanoi
  • The Anh Luu Central Institute for Natural Resources and Environmental Studies, Vietnam National University Hanoi, 19 Le Thanh Tong, Hoan Kiem, Ha Noi, Vietnam
  • Minh Truong Dao Central Institute for Natural Resources and Environmental Studies, Vietnam National University Hanoi, 19 Le Thanh Tong, Hoan Kiem, Ha Noi, Vietnam


Pseudomonas putida, phytoremediation, soil fertility, metal-contaminated soil, weed


Heavy metal pollution of soils in being a serious problem for sustainable agriculture. A promising solution for phytoremediation of metal-contaminated soils is to use plants in combination with phosphate-solubilizing bacteria (PSB). In this study, a total of 30 soil samples were collected from different locations in Nam Dinh, Vietnam. They were used to isolate PSB from paddy soil on Pikovskaya agar media, and their ability in improving the phytoremediation of lead (Pb2+) by a weed plant (Echinochloa colona) as well as in promoting the growth of E. colona under Pb stress condition was investigated by pot experiments. Total 07 PSB were isolated and the ND04 showed the ability in solubilizing multiple P sources ( Ca3(PO4)2, AlPO4, FePO4, and phytate) with corresponding P solubilizing levels were 530.12, 50.13, 25.02, and 3.58 mg/L PO43–-P, respectively. Moreover, the ND04 strain was identified as Pseudomonas putida (accession number FJ976605.1) and produced the highest values of available P (1.67 mg/L) in Ca3(PO4)2 ‑incubated soil experiments. Furthermore, the ND04 inoculation significantly enhanced the growth of E. colona and also increased the phytoremediation efficiency of Pb from Pb-contaminated soil. These results suggest the ND04 could potentially use to construct novel constructed wetlands for phytoremediation of metal-contaminated soil.


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