OGHENEROBOR B. AKPOR,IFEOLUWAO KOMOLAFE, OLAREWAJU M. OLUBA, OLAYINKA O. ALABI, ABIGAIL G. ADEYONU AND AYOOLAJ SHOYOMBO
Abstract
The use of chemical fertilizers in growth promotion in plants has been in practice for a long time. However, because of the detrimental and adverse effects of chemicals on plants and human, Plant Growth Promoting Rhizosphere (PGPR) bacteria are emerging as substitutes. This paper was therefore aimed at reviewing growth promotion by PGPR bacteria, with emphasis on their mechanism of action and application. There is a mutualistic relationship between plant and microbes, as the rhizosphere is known to release root exudates that helps in microbial growth and proliferation while rhizosphere microbes contribute to the growth of plants, directly and indirectly. Some of the direct contributions of PGPR bacteria to plant growth include nitrogen fixation, phosphate solubilization and hormone production. Indirectly, PGPR bacteria contribute to plant growth through the inducement of systemic resistance, and the production of antibiotics and bacteriocins. PGPR bacteria can be applied as biofertilizers, antibiotics, in stress management and rhizoremediation. The use of PGPR technology could serve as valuable eco-friendly alternative to chemical fertilizers and pesticides.