IN VITRO ASSAY OF BIOMOLECULES, SYNTHESIS OF STRESS REDUCING PROLINE AND PERFORMANCE OF METAL TOLERANT BRADYRHIZOBIUM INOCULATED GREENGRAM (Vigna radiata L. Wilczek) UNDER METAL STRESS

M.S. KHAN¹, A. RIZVI²*, A. ZAIDI³, S. SAIF^4
1Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh, 202002; U.P., India
²Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh, 202002, U.P., India
³Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh, 202002, U.P., India
⁴Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh, 202002, U.P., India
* Corresponding Author : asfarizvi09@gmail.com

Received : 20-10-2017     Accepted : 26-10-2017     Published : 28-10-2017
Volume : 9     Issue : 10       Pages : 967 - 973
Int J Microbiol Res 9.10 (2017):967-973

Keywords : Bioremediation, Bradyrhizobium, Greengram, Heavy Metals, Proline
Academic Editor : Bibhuti Bhusan Sahoo, Dr Rakesh Kumar Sharma, Saheb Pal, Shivendu Pratap Singh Solanki
Conflict of Interest : None declared
Acknowledgements/Funding : Author are thankful to Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh, 202002, U.P. for providing all the facilities to complete this study
Author Contribution : MSK and AZ have conceived and designed the research plan. AR performed the experiments and drafted manuscript. AZ, AR and SS also contributed in data analysis, discussion and overall development of manuscript. All authors have read and approved the final

Heavy metals are serious environmental pollutants and deleteriously affect the sustainability of microbes, plants and humans. Considering the toxicity of heavy metals, the present study was designed to isolate metal tolerant plant growth promoting rhizobacteria and to assess their plant growth promoting activities in the presence and absence of heavy metals. The best performing metal tolerant Bradyrhizobium strain C4 was selected to evaluate its impact on biological and chemical properties of greengram grown under metal stress. Bradyrhizobium sp. (vigna) strain C4 showed maximum tolerance to copper (1600 g/ml), cadmium (200 g/ml) and chromium (400 g/ml) and produced siderophore, ammonia, cyanogenic compounds and synthesized indole-3-acetic acid under metal stress. Bradyrhizobium strain C4 enhanced the overall growth of greengram plants grown in soils stressed with/without varying concentrations of copper, cadmium and chromium. Proline concentration in greengram plants increased with increasing concentration of metals but declined significantly in Bradyrhizobium sp. (vigna) inoculated plants compared to control plants. The intrinsic abilities of growth promotion, enhanced performance of metal tolerant Bradyrhizobium sp. (vigna) inoculated plants and reduction in proline level of the inoculated plants grown under metal stress are indicative that Bradyrhizobium sp. (vigna) could be used for developing rhizobial inoculant for optimizing the production of greengram in soils polluted even with copper, cadmium and chromium.

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