ISOLATION AND CHARACTERIZATION OF PGPR ISOLATES FROM RHIZOSPHERE SOILS OF GREENGRAM IN WARANGAL DISTRICT OF TELANGANA

Abstract

Plant growth promoting rhizobacteria (PGPR) stimulate plant growth and improve crop productivity by  direct or indirect mechanisms. In our present study, a total of 120 bacterial strains were isolated from rhizosphere soils of Vigna radiata L. Wilckzeck, from Warangal Dist. , Telangana, India.  Among them, 35 potential bacterial strains showing antagonistic and PGP activities were selected for characterization. Out of which six competent strains were selected which showed maximum plant growth promoting (PGP) activities and further subjected to the cell wall degrading enzyme production and seed germination test. All isolates exhibited production of indole acetic acid, whereas five isolates produced HCN and solubilized inorganic phosphate. Subsequently, to investigate in vitro test for all the six isolates the antagonistic activity against, Fusarium oxysporum, Colletotrichum capsici, Rhizoctonia solani, Macrophomina phaseolena spp. This result suggests that these PGPR isolates may be used as bio fertilizers as well as biocontrol agents to enhance the growth and productivity.