[High effective phosphate-solubilizing bacteria: their isolation and promoting effect on corn seedling growth]

By using modified PVK plate method, 44 strains of phosphate-solubilizing bacteria (PSB) were isolated from the root surface of wild plants growing well in calcareous soil. After 7-day incubation in a liquid medium NBRIP, the total P in the cultures of strains K3 and K9 reached 643.2 microg x ml(-1) and 608.5 microg x ml(-1), and soluble P was 584.8 microg x ml(-1) and 606.4 microg x ml(-1), respectively. About 12.9% of tricalcium phosphate was dissolved, being 9.5 times higher than CK. Pot experiment showed that the plant height, stem diameter, and dry mass of corn seedling were significantly higher in PSB treatments than in CK. Applying PSB agent with manure as a carrier could significantly increase the seedling's dry mass, in comparing with applying PSB agent alone. The strains K3 and K9 were identified as Pseudomonas.