Characterization of Rhizobium isolated from root nodules of Trifolium alexandrinum.

Abstract

Strains of root nodulating bacteria were isolated from root nodules of Trifolium alexandrinum growing widely in different agroclimatic regions of Dehradun. After authentication test, 85 isolates those nodulate host plant along with one standard strain Rhizoboium trifolii (MTCC 905) were selected. The isolates were further subjected to morphological, biochemical and physiological characterization to ascertain their taxonomic position. Antibiotic resistance pattern of all isolates was also evaluated against thirteen antibiotics. Most of the isolates exhibited highest resistance to streptomycin and least with tetracycline. On the basis of morphological, biochemical and physiological characters and their comparison with standard strain R. trifolii (MTCC 905) most of the characteristics were found similar to the standard strain.