Journal of Pure and Applied MicrobiologyVol. 9 No. 2

Characterization and Evaluation of Bacterial Isolates Solubilizing both Potassium and Phosphorus from Different Rhizosphere Soil

K.N. Basavesha and V.P. Savalgi

Department of Agricultural Microbiology, University of Agricultural Sciences, Dharwad- 580 005, India.

Received on 28 December 2014 and accepted on 10 January 2015



Fifty isolates of bacteria solubilizing both potassium and phosphorus was isolated from rhizosphere soil collected from different locations on modified Aleksandrov medium containing potassium and phosphorus sources. All the isolates were characterized upto genus level based on morphological and biochemical characters. Thirty nine isolates were Gram positive, rod shaped and spore former were identified as Bacillus species and 11 isolates was Gram negative, rod shaped and non spore former were identified as Pseudomonas species. And functionally these isolates possessed the ability to solubilize both potassium and phosphorus minerals in medium. The maximum solubilization of potassium and phosphorous observed at 15 days after incubation ranged from 2.36 to 29.83 ?g/ml and 3.44 to 14.25 per cent, respectively. They also produced growth promoting substance like IAA (3.38 to 8.90 ?g/25ml) and GA (1.27 to 3.67 ?g/25ml).

Keywords : Bacillus, Pseudomonas, Aleksandrov medium,