COMPARATIVE EFFICIENCY OF RHIZOBIUM BRADYRHIZOBIUM SPP STRAINS IN NODULATING CAJANUS-CAJAN IN RELATION TO CHARACTERISTIC METABOLIC ENZYME-ACTIVITIES/

The comparative symbiotic properties of Rhizobium spp. and Bradyrhizob ium spp. strains infecting pigeon pea were evaluated. Bradyrhizobium s trains (Cajanus) were found to be superior to Rhizobium strains (Cajan us) and the superiority was ascertained to be due to the higher enzyme activity of the tricarboxylic acid (TCA) cycle in comparison to Rhizo bium spp. strains. Moreover, metabolic superiority or rapid growth rat e does not necessarily correlate with symbiotic effectiveness. The sym biotic performance of isolates varied with the host cultivar. The dry matter accumulation could be correlated with the total acetylene reduc tion activities rather than nodule number or nodule fresh weight per p lant.