Abstract: This work is to isolate and identify the phosphate-solubilizing microorganisms and develop microbial complex agents targeting for solving the problems of agricultural non-point source pollution. The organic phosphorus pesticide “chlorpyrifos”,“trichlorfon” and insoluble inorganic phosphorus Ca₃（PO₄）₂ were used as phosphorus source to screen and identify the phosphate-solubilizing microbe from soil,as well as analyze their phosphate-solubilizing capacity. The result showed that three phosphate-solubilizing bacterial strains（W,Y and B）were isolated from the soil. All three strains were gram-negative strains. The degradation results of organophosphorus pesticides showed that strain W had the strongest degradation rate of trichlorfon with 17.39%,and strain B had the strongest degradation rate of chlorpyrifos with 23.06%. All three strains solubilized significantly solid insoluble phosphate,and the B strain had the highest phosphorus-solubilizing capacity of 96.31 mg/L. The solubilizing phosphate results of single strain and compound strains showed that the effect of compound strains was significantly better than single strain. When W,Y,and B strains mixed with EM,the phosphorus-solubilizing capacity rose to 119.46 mg/L,and the phosphorus-solubilizing capacity in paddy fields and greenhouse soil was improved to 18.38 mg/L and 14.08 mg/L,respectively. In conclusion,three strains isolated from soil have the abilities of degrading organic phosphorus pesticide and solubilizing inorganic phosphorus Ca₃（PO₄）₂. The compound strains significantly improved the phosphorus-solubilizing capacity of soil significantly.

Key words: organophosphorus pesticides, inorganic phosphorus, compound microbial, phosphate-solubilizing bacteria