Screening and Characterization of Phosphate-Solubilizing Microorganisms at High Temperature

Five strains of thermophilic phosphate-solubilizing microorganisms,named P1～P5,which could strongly dissolved phosphate were isolated in the high temperature period from composting.P1 could grow under the temperature from 35～(53 ℃),the others under 35～(50 ℃) and the optimum temperature is 40～(50 ℃).Through high-temperature shaking culture of P1～P5 under(50 ℃),available phosphorus content,micro-phosphorus content,total available phosphorus and pH were respectively measured.The results showed that under(50 ℃),phosphate-solubilizing microorganisms P1～P5 were cultured by shaking bed,after 7days,the available phosphorus content,micro-phosphorus content and total available phosphorus were 30.9 ～47.6(mg/L),116.4～164.4(mg/L) and 152.1～201.6 (mg/L),respectively.The fermentation liquid was obviously in acidity,but there was not significant relationship between rock phosphate solubilization capacity and the pH.The results prove that micro-phosphorus is very important for test of capacity to dissolve the rock phosphate.In conclusion,five tested microorganism had stronger capacity to dissolve the rock phosphate and higher alive when they grow at high temperature.