Field and pot experiments were conducted on five agricultural soils from Kiangsu province of various productivity with pH values ranging from 4.5 to 7.8. Fractions of soil phosphate and rate of mineralization of soil nitrogen through incubation were measured. The soils showed a wide range of nutritive levels of phosphorus and nitrogen to these soils, various rate of ammonium sulphate and manures were applied at the foundation of superphosphate and the yields of wheat, millet, rice, soybean and pea analysed.