Role of metal resistant plant growth promoting bacteria in ameliorating fly ash to the growth of Brassica juncea

In this study, we have shown that the plant growth promoting bacterial strain NBRI K24 and strain NBRI K3 from fly ash (FA) contaminated soil reduce the toxicity of Ni and Cr in Brassica juncea (Indian mustard) and promote plant growth under pot culture experiments. Isolated strains NBRI K24 and NBRI K3 were characterized based on the 16S rDNA sequencing and identified as Enterobacter aerogenes and Rahnella aquatilis respectively . Both the strains were siderophore producing and found capable of stimulating plant biomass and enhance phytoextraction of metals (Ni and Cr) from FA by metal accumulating plant i.e. B. juncea. Concurrent production of siderophores, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, indole acetic acid (IAA) and phosphate solubilization revealed their plant growth promotion potential.