Abstract: 【Objective】 Inoculation technology and field application of cotton rhizosphere phosphorus-solubilizing P.Taiwanensis WJP-7. 【Method】 In this paper, the self-selected high-efficiency phosphorus-dissolving strain P.taiwanensis WJP-7 was used as the starting strain, and it was propagated and cultured in the optimized Pseudomonas fermentation medium. 【Results】 The results showed that the shake flask fermentation medium was optimized by orthogonal experiment, and the medium formula was determined as: peptone 20 g/L, magnesium chloride 15 g/L, potassium sulfate 1.4 g/L.The number of viable cells reached 3.6×10⁹CFU/mL.The maximum viable bacteria count of the optimal medium for enrichment fermentation in shake flask was 3.60×10⁹CFU/mL.The control effect of strain WJP-7 water treatment on Verticillium wilt at flowering stage was 44.57%, and the control effect at flocculation stage was 50.53%.The application of microbial inoculants on cotton field soils had no significant increase in total nitrogen content (P>0.05), but significant effects on other nutrients and pH values (P<0.05).The yield increase rates were 14.35% and 19.51%. 【Conclusion】 The shake flask fermentation medium of Pseudomonas Taiwan WJP-7 was optimized by orthogonal experiment.Except for the total nitrogen content in cotton field soil, it has a significant effect on other nutrients and pH value (P<0.05), with a significant yield increase effect.