Isolation and characterization of plant growth-promoting rhizobacteria from soil

Abstract

Plant and microorganisms relation has a major effect on productivity since human began to rely extensively on agricultural crops for food. Biotechnology has explored the beauty of the microbial world in various fields including agriculture. Soil microbial populations affect plant health and fitness along with soil quality. Plant Growth Promoting Rhizobacteria (PGPR) sets an example in this field. These are underground solutions for above ground problems related to plant. The potentiality of PGPR in agriculture is gradually increasing as it provides an attractive way to replace the use of chemical fertilizers and pesticides. Keeping in view of increasing environmental pollution with a decline in soil health due to use of chemical fertilizers and pesticides, the present study is conducted using bacterial isolates from Vigna radiata for plant growth promotion activities. A total seven strains were isolated and designated as AN12, AN13, AN14, AN15, AN16, AN17 and AN18. Isolated strains were identified with the morphological, biochemical and molecular screening. Antifungal activity was observed by dual culture technique against two phytopathogens viz Fusarium oxysporum and Alterenia solani. Isolated strains were examined for plant growth promoting activities which revealed that some strains are involved in a significant increase in various plant growth parameters. The current study therefore suggested that selected strains of PGPR can be used as biofertilizers as well as biocontrol agents. Hence, these isolates can be further formulated and used for field applications.