Chapter 11 - Potassium solubilizing microorganisms as soil health engineers: An insight into molecular mechanism

Abstract

Potassium (K) is one of the most abundantly absorbed essential macro-nutrient and also plays vital role in plant’s growth and metabolism. The soil K reserves are generally large, but a considerable proportion of it is available in the form of insoluble K minerals, whereas a small fraction of potassium is accessible to plants due to its available form absorbed directly by the plant roots. Several microorganisms convert the available form of K from unavailable forms. Hence, the potassium solubilizing bacteria (KSB) possess a promising approach to enhance the potassium availability in soils and play an important role in the potassium nutrient management under K-limited soils and reduce the use of potassium-based chemical fertilizers. KSB solubilizes different types of K in the soil by secreting organic acids into available forms that boost plant growth, yield, and the soil’s fertility status. This chapter briefly summarizes the mechanism and PGPR attributes of KSBs.