Plant Growth Promoting Rhizobacteria (PGPR) and their various mechanisms for plant growth enhancement in stressful conditions: a review

The population has been rising in a rapid state and so is the demand of basic necessities like food requirements. Today agriculture demands increase in yield with a substantial decrease in chemical fertilizer and pesticides that are responsible for huge environmental degradation. Today a huge part of yield has been lost due to various stresses plant are subjected too. It could be broadly divided into biotic and abiotic stress. Meanwhile, plant growth promoting rhizobacteria has promised us a substantial agriculture development platform. These are generally a group of microorganism that is found either in the plane of the rhizosphere or above root impacting some positive benefits to plants. These stresses include but in no sense limited to ion toxicity, pathogen susceptibility, physiological disorder, salinity, temperature, flooding, pH etc. In response to the above-mentioned stresses plant with PGPR exhibits various sorts of response to handle these unfavorable conditions. They could be further divided into direct and indirect mechanics. PGPR has shown both synergistic as well as antagonist interaction with microorganism inhabiting in near surrounding to boost plant favorably. This review has tried to undertake all possible mechanism of PGPR along with reported studies for various possibilities through which sustainable agriculture development could take place. This review has tried to understand the mechanism to take PGPR at a commercial level under bio-fertilizer.