KSM soil diversity and mineral solubilization, in relation to crop production and molecular mechanism

Abstract

Bio-weathering and biomineralization are geochemical processes of the decomposition of rocks and minerals which are mediated by the living organisms. These processes play a fundamental role in the release of nutrients from rocks and minerals. Microorganisms, higher plants, and animals can weather rock aggregates through biomechanical and biochemical attack. Among such microbes, the information especially on phosphate solubilizers has been well documented; however, there are very few studies on the use of potassium-solubilizing microbes (KSMs) for the release of the native soil K. The strains of Pseudomonas, Bacillus, Aspergillus, Penicillium, etc. are some known K solubilizers. The principal mechanism for the microbe-mediated release of potassium from minerals is through the production of organic acids. A short overview of the KSMs and their effect of K uptake and crop growth are presented herein. K dynamics in soils and its availability to plants, metabolic pathways effecting the release of organic acids by KSMs, are covered. The aspects of immobilization of KSMs for the ease of application and the role of VAM in K mobilization have also been explored.