Abstract:

In order to filter out the fine phosphate-solubilizing strains, for the further development of bio-fertilizer to provide basic information and theoretical and practical basis, 431 phosphorus-solubilizing bacteria were isolated from rhizosphere soil in differrent stand ages of Pinus massonuana sand-fixation forest by NBRIP solid medium. There was different amount of phosphate-solubilizing microorganism in different stand ages of Pinus massonuana sand-fixation forest rhizosphere, the amount in different stand age was in the order: 15 years>20 years>25 years>10 years>2 years. 11 stains were selected by means of phosphorus hole, their D/d ratio was higher. Phosphorus solubilizing capability of the strains with the molybdenum blue spectrophotometry indicated that yL14 showed stronger ability of dissolving phosphorus, based on the physiological and biochemical characteristics and 16S rDNA sequences, isolate yL14 belonged to the genus Pseudomonas fulva. Its phosphate solubilization capacity was 65.14 mg/L. According to the experiments, there was not directly relationship between the phosphate-dissolving capacity of phosphorus-solubilizing bacteria and the pH reduction of liquid media. The strain could be used as potential strains for biofertilizer manufacture.