描述
In present era, world population is budding drastically, and such skyrocketing population growth is proving burdensome to agricultural productivity. Inorder to fulfill the food demands of such blooming population, farmers apply chemical fertilizers in rampant way, which causes pollution (e.g. soil and water) and in return it harms ecosystem and humans (e.g. blue baby syndrome, goiter etc). So, world is yelling for a better, ecofriendly and economical substitute of these chemical fertilizers. Plant growth-promoting rhizobacteria (PGPR), could come to the rescue, as they are by, of and for the nature. Hence, the chapter shed light on multitudinal arrays of PGPR, viz, their abode and niche, types and mechanisms of action to enhance plant growth and yield. A detailed account of novel mechanism i.e. direct mechanisms, regulated by PGPR are addressed here, and much emphasis has been laid on direct mechanisms, particularly, nitrogen fixation, phosphate solubilization, zinc solubilization and phytohormones production (Indole-3-acetic acid (IAA), Cytokinins and Gibberellins), because they are the majoring mechanics, indulged in uplifting plant growth and productivity, more or less.