218-221Relative distribution of limnotolerant (freshwater tolerant) and halotolerant (saline water tolerant) phosphate solubilizing bacteria were estimated from 3 stations in Vellar estuary using different media. In addition, nutrients such as nitrite, nitrate silicate and phosphate were also analysed. Vertical distribution of phosphate dissolving bacteria at each station showed higher concentration in the sediments than in the corresponding overlying water. The ratio between the marine and freshwater phosphate solubilizing bacteria altered due to variation in salinity. In general, clayey sediment harboured more phosphate solubilizing bacteria than the sandy ones. Influences of abiotic factors like organic carbon, total phosphorus, total nitrogen and salinity on the occurrence and distribution of phosphate solubilizing bacteria were discussed
