Archives

Phosphates solubilising bacterial spp. isolated from saline soil near Kolhapur city were tested for
IAA production using pure tryptophan. All isolates were then screened for production of IAA using
natural sources of tryptophan such as soybean flour, pumpkin seed powder and watermelon seed
powder. IAA production was tested qualitatively and quantitatively. Most effective phosphate
solubilising bacterial spp. was identified as Enterobacter cloacae subsp. cloacae YCA on the basis
of its morphological, biochemical characteristics and 16s rRNA gene sequencing. The isolate was
found to give high yield of IAA (0.89 mg/ml) from watermelon seed powder and it was also found to
produce other plant growth promoting substances such as siderophore, ammonia, organic acids and
hydrogen cyanide. The isolate was moderate halophile as it tolerates NaCl and KCl up to 6%. The
amount of soluble phosphorus was also found to increase over initial level in the pot where isolate
was inoculated. Results of pot trials using saline and fertile soil indicate the potential use of our
isolate in enhancing plant growth.
Keywords: Indole-3-acetic acid, Nutrient broth, Kartznelson and Bose medium, Siderophore, Saline soil.