Characterization of Rhizobium from various non-traditional arid legume crops in M.P.

An attempt has been made to characterize the Rhizobia isolated from non traditionalarid legume crops viz., cowpea, moth and guarfrom various regions of Madhya Pradesh. All the isolates were characterized phenotypically and biochemically. Growth of pure Rhizobial isolates on yeast extract mannitol (YEM) medium having variable range of pH (4.0 to 10.0), different concentrations of PEG (30%, 45% and 60%) and NaCl (0.1 to 1M) have been studied to screen out stress tolerant isolates. Among the eight isolates, cowpea isolate R1 are able to produce auxin 42.37 μg/ml and EPS 689.97 μg/ml and R2 isolate of cowpea are also able to solubilize 230.26 μg/ml phosphates. Moth isolate R5 are able to tolerate 1000mM concentration of NaCl and guar isolate R7 are able to survive up to 60% drought. The stress tolerant traits of these Rhizobia are of potential value from the point of view of biofertilization of legume seedlings in arid and semi-arid tropics of Madhya Pradesh.