Functioning of Plant Growth Promoting Rhizobacteria (Pgpr) and Their Mode of Actions: An Overview From Chemistry Point of View

In one stage of mankind's struggle to keep pace with ever increasing demand of food due to accelerating world population, chemical fertilizers contributed enormously to produce sufficient food products. However, a stagnation in the crop productivity along with decreasing soil fertility status and environmental pollution due to continuous, excessive, and imbalanced use of chemical fertilizers. In this scenario, plant growth promoting rhizobacteria (PGPR) become a natural choice as an alternative to the fertilizer to alleviate excessive consumption of fertilizers because PGPR not only promote nutrient availability to plants as biofertilizers but also performin several ways to stimulate plant growth and hence their productivity. In this review, an attempt has been made to highlight the main activities of PGPR in soil and plants, and to analyse their mode of actions from chemistry point of view.