Identification and characterization of potassium solubilizing bacteria (KSB) from Indo-Gangetic Plains of India

The present investigation comprises a total of fifty potassium solubilizing bacterial (KSB) strains which were isolated from Oryza sativa, Musa paradisiaca, Zea mays, Sorghum bicolor and Triticum aestivum L. These strains were evaluated for their ability to solubilize the fixed K from waste biotite (WB). On the basis of K-solublization, the seven most efficient KSB strains were evaluated for K-solublizing dynamics from the WB at 7, 14 and 21 DAI (days after incubation) on MAMs (Modified Solid Aleksandrov Medium). Further, these screened seven KSB strains were used for their morphological, physiological and molecular chacterization. The KSB strains Bacillus licheniformis BHU18 and Pseudomonas azotoformans BHU21 showed significantly higher K-solublization 7.22 and 6.03 μg mL-1 at 30 °C and pH 7.0, respectively. A significantely higher zone of solubilization significantly higher was recorded with Pseudomonas azotoformans BHU21 (3.61 cm). Bacillus licheniformis BHU18 produced significantly higher (~23 μg mL-1) concentrations of indole-3-acetic acid. The diversity of KSB as bioinoculants to release potassium provides a win-win situation. Therefore, it is crucial to adopt efficient KSB strain interventions for the judicious use of chemical and biological resources for maximizing food production while reducing pollution and rejuvenating degraded land for agricultural benefit. © 2016 Elsevier Ltd.