Formulation of a compatible microbial consortia of nitrogen fixing, phosphate solubilising and potash mobilizing bacteria for optimizing nutrient supplementation to tuberose

Abstract

The present investigation was conducted with the aim to isolate and characterize Azotobacter, phosphate solubilising bacteria (PSB) and potash mobilizing bacteria (KMB) from rhizosphere soil of tuberose and formulate consortium of Azotobacter, PSB and KMB. Three isolates each of Azotobacter, PSB and KMB were obtained from soil samples collected from three different locations of Pune region. Based on morphological and biochemical characterization, the highly efficient nitrogen fixing isolate (A I), PSB isolate (P III) and KMB isolate (K II) were identified as Azotobacter chroococcum, Bacillus subtilis and Frateuria aurantia respectively and used for the formulation of microbial consortium. Among the different culture media formulated, M III media having Glucose (10 g/L), Ammonium sulphate (0.4 g/L) and Yeast extract (1 g/L) recorded maximum growth and c.f.u. count of Azotobacter, PSB and KMB. These three beneficial organisms were found compatible with each other when grown on M III culture medium.