Genotypic Characterization of Indigenous Rhizobium Strain from Cultivated Cowpea (Vigna unguiculata L.) in Bangladesh

A gram negative strain of Rhizobium sp. SOY7 has been isolated from root nodules of cow pea (Vigna unguiculata L.) which was later identified on the basis of biochemical tests and 16S rDNA sequencing. The optimum culture condition of Rhizobium sp. SOY7 was determined at pH 7.0 and 28ËšC temperature. The strain was resistant to most of the antibiotics used in this study except Tetracycline, Ceftazidime, Pefloxacin, Cotrimoxazole and Mecillinam. Moreover, the isolate was sensitive to the higher concentration of NaCl (>1%). The strain is capable to produce nodules when induced rhizobia as inoculants and resulted insignificant changes in plant growth characteristics. The most abundant nodulation and improved growth of the legumes were determined in plants inoculated with Rhizobium sp.…