Study on isolation, identification and culture condition of rhizosphere phosphate-solubilizing microorganisms from red paddy soil of king grass

Twenty-one strains of Phosphate-solubilizing bacteria were screened from red paddy soil samples of king grass, and physiological and biochemical characters of these strains were determined. Finally, 4 phosphate-solubilizing bacterial strains with stronger phosphate-solubilizing ability but without antagonism were screened, and combined as flora of phosphate-solubilizing bacteria, then their optimum temperature, optimum initial pH and optimum growth time were studied. The results showed that Strains 2-5, 2-6, 2-8-1, 2-9, 3-8, 3-8-1, 4-1-2, 4-2, 4-5 were Bacillus megaterium, Strains 2-7-1, 2-8, 3-6-1, 4-1-1, 4-3 were Burkholderia sp., Strains 4-4, 2-7, 2-8-2, 3-6, 4-3-1 were Bacillus cereus. The optimum temperature for phosphate-solubilizing bacteria flora was 25℃-30℃, the optimum initial pH was 6.5-7.0 and the optimum growth time was 90 h.