Abstract

Arvind Kumar, Poonam Bhargava and Lal Chand Rai*

Six phosphate solubilizing bacteria (PSB) were isolated from paddy fields of Eastern Uttar Pradesh, India harboring low available phosphorus. Taxonomic delineation employing morphological, biochemical, 16S rRNA gene sequences and phylogenetic affiliations suggests that they are members of Enterobacter and Exiguobacterium genera. Of the six isolates, Enterobacter sp. LCR1 and LCR2 exhibited high level (568 - 642 g/ml) of phosphate solubilization in NBRIP liquid medium. Exiguobacterium sp. LCR4 and LCR5 showed increased phosphate solubilization efficiency under alkaline pH while Enterobacter sp. LCR3 remained unaffected. At high salt and temperature, Enterobacter sp. LCR1 and LCR2 produced 1.6 fold soluble phosphorus in comparison with earlier studies. Thus, these isolates may be useful for the development of potential bio-inoculants for soils having alkaline pH, high salt, temperature and insoluble phosphorus.