Potential Plant Growth Promoting activity of Pseudomonas fluorescens sp. isolated from Cotton (Gossypium hirsutum) crop.

Abstract

Plant–bacterial interactions in the rhizosphere are complex and determine the plant health, productivity and soil fertility. The Plant Growth Promoting bacterial strains were isolated from the rhizospheric soil of the cotton plant from various places of Haryana, India. One of the most promising isolate exhibiting maximum PGP traits was identified as Pseudomonas fluorescens based on the biochemical characterization, phenotypic microarray analysis and 16S rDNA sequencing. The isolate was initially screened on the basis of the seed germination assay and was then screened in vitro for their plant growth promoting traits like production of indoleacetic acid (IAA), ammonia production (NH3), hydrogen cyanide (HCN) production, siderophore production, phosphate solubilization, ACC deaminase activity and acetylene reduction activity (ARA). The isolate exhibited positive results for ammonia and siderophore production and phosphate solubilization. The isolate also showed acetylene reduction activity (ARA). The results indicated that P. fluorescens has significant potential when applied to soil–plant system to uncover its efficacy as effective PGPR.