Physiochemical Characterization of Fluoride (F) Contaminated Soil and its Microbe-Assisted Bioremediation by Prosopis juliflora

Fluoride (F) contamination is a worldwide problem which has severe consequences on human and animal health. Physiochemical characteristics of F-polluted soil in different sites (Banasthali, Rajasthan, India) were tested. Soil pH (7 ? 9.3), E.C (2.1 ? 6.1 dSm-1), O.C (0.30% ? 0.60%), N (11.4 ? 53.4), P (3.3 ? 5.8), K (106 ? 117), S (1.3 ? 8.3), Ca (11.7 ? 14.2), Mg (1.8 ? 11.7 kgha-1) and total Fe (3.6 ? 5.6), Mn (1 ? 2.4), Zn (0.30 ? 2.6), Cu (0.70 ? 4.1) and total F contents (9.6 ? 11.0 mgkg-1) were observed. Prosopis juliflora is a hyperaccumulator plant, known and suitable species for phytoremediation of F polluted soil. A repeat experiment for confirmation using F contaminated soil with amendments of Pseudomonas fluorescence (P.F) and Pseudomonas aeruginosa (P.A) were applied to soil in small scale for 120 days. Moreover, total plant biomass increase (67.73% ? 74.33%), chlorophyll reduced (50% ? 34.67%) and mineral contents enhanced (46.38% ? 58.68%) at 100 mgkg-1 were found as compared to the control. These two strains, increased bioaccumulation factor (BF) 0.22 ? 2.89 and translocation factor (TF) 0.63 ? 1.08 of plant, accumulated high amount of F in root. Comparative results (biomass, chlorophyll, mineral content, TF and BF) between P.F and P.A indicated that applications of Pseudomonas fluorescence significantly (P ? 0.05) impacted on the study of P. juliflora tolerance capacity. Results showed P. juliflora has good tolerance capacity when soil F concentration at 100 mg kg-1 with P.F ? 108 cfu ml-1kg-1 of soil. In conclusion, Pseudomonas fluorescence identified in our study may be potentially used for phytoremediation purpose in field scale.