title: Stimulated phytoextraction of metals from fly ash by microbial interventions.
abstract: Various combinations of fly ash tolerant bacteria isolated from the rhizospheric zone of Typha latifolia naturally growing on a fly ash dump site were tested for enhanced metal uptake by Brassica juncea grown in fly ash amended with press mud. After enrichment of the bacteria in a nutrient broth, they were subsequently applied to the rhizospheric zone of B. juncea in different combinations. When the metal analysis was done in the plants at their maturity, it was revealed that out of 11 bacterial consortia prepared from the different combinations of four bacterial strains, Micrococcus roseus NBRFT2 (MTCC 9018), Bacillus endophyticus NBRFT4 (MTCC 9021), Paenibacillus macerans NBRFT5 (MTCC 8912) and Bacillus pumilus NBRFT9 (MTCC 8913), a combination of NBRFT5, NBRFT4 and NBRFT9 (ST3) was found to have induced the highest metal accumulations as compared to other consortia. The bioaugmentation of the ST3 consortium enhanced Fe accumulation by 247%, Ni by 231% and Zn by 223% in B. juncea as compared to control plants. These values were found to be significantly higher than the other bacterial consortia. Bacteria were also found to produce siderophores which could enhance the metal uptake by plants through metal mobilization. Besides siderophores, bacteria are also known to produce protons, organic acids and enzymes which enhance the metal mobilization and boost the phytoextraction process. The translocation of metals from root to stem was invariably higher than from stem to leaf. Hence, ST3 was adjudged the best consortium to be used in the field application to accelerate the phytoextraction of metals from fly ash by B. juncea.
authors: National Botanical Research Institute (Council of Scientific and Industrial Research), Lucknow, Uttar Pradesh, India.
authors: Sadhna
authors: S
authors: Tiwari
authors: S N
authors: SN
authors: Singh
authors: S K
authors: SK
authors: Garg
mesh_terms: D001673:Biodegradation, Environmental; D018533:Biomass; D001937:Brassica / Q000254:growth & development / Q000378:metabolism* / Q000382:microbiology; D060729:Coal Ash / Q000032:analysis; D008670:Metals / Q000378:metabolism*; D018517:Plant Roots / Q000382:microbiology*; D012988:Soil Microbiology; D032401:Typhaceae / Q000382:microbiology*
chemical_list: D060729:Coal Ash; D008670:Metals