Review on plant growth promoting rhizobacteria and its effect on plant growth

Abstract

Both biotic and abiotic stresses are major constrains to agricultural production. Under stress conditions, plant growth is affected by a number of factors such as hormonal and nutritional imbalance, ion toxicity, physiological disorders and susceptibility to disease. Plant growth under stress conditions may be enhanced by the application of microbial inoculation including PGPR. These microbes can promote plant growth by regulating nutritional and hormonal balance, producing plant growth regulators and solubilizing nutrients. In addition to their interactions with plants, these microbes also show synergistic interactions with other microbes in the soil environment. These interactions may be vital for sustainable agriculture because they mainly depend on biological process rather than on agrochemicals to maintain plant growth and development as well as proper health under stress conditions. Biological interactions of PGPR with soil microbes are believed to cause a cumulative effect on all rhizosphere components which regulating the plant growth.