Identification and Biochemical characterization of Plant growth promoting Rhizobium and evaluating its potential as Bioinoculant isolated from root nodule of Cowpea (Vigna unguiculata)
Nanthini. K1, J. Divakaran*2 and P. Sivasakthivelan3
1,2,3Department ofAgricultural Microbiology, Faculty of Agriculture, Annamalai University Annamalai Nagar - 608 002 (India) *2Corresponding author: divakaranakash@yahoo.com
ABSTRACT
Cowpea is a leguminous crop which is used as a food for humans, feed for livestocks and serves as the revenue generating agricultural crop for farmers. Rhizobium is a legume specific organism, which has the potential to fix atmospheric nitrogen. Rhizobia can be characterized by different methods. In this study, Rhizobium is isolated from the root nodule of cowpea plant. The isolated Rhizobium strain was biochemicallycharacterized by different methods and screened for plant growth hormone producing traits. It was observed that the Rhizobium isolate significantlyproduced IAA, Ammonia, Siderophore and HCN. The maximum IndoleAceticAcid andAmmonia production was recorded as 101.5 µg/ml and 79 µg/ml respectively. The isolate also tested positive for siderophore and HCN production. From this study, we conclude that the Rhizobium strain can be used for improving plant growth promotion.