Effect Of Application Of Organic-Inorganic Mixed Fertilizers On Growth Of Crops And Soil Nitrogen Supply

Pot and field experiments were carried out to study the effect of application oforganic-inorganic mixed fertilizers on growth, yields, and quality of crop and soil nitrogensupplying characteristics. The results obtained are listed as follows.1 Biomasses of spinach, rice and tomato were increased by 52.7%, 46.4% and 46.3%respectively in the application of the organic-inorganic mixed fertilizers compared with CK(no fertilizers applied) and they were also increased by 25.7%, 12.1% and 25.8% comparedwith the treatments of chemical fertilizer alone, respectively. This demonstrates that theorganic-inorganic mixed fertilizers can have a better effect on the growth of crops even thanchemical fertilizer.2 Nitrogen taken up by crops in the application of the organic-inorganic mixedfertilizers were 87.2%, 36.2% and 26.6% higher than those of CK, respectively, and 38.0%,18.6% and 10.6% higher than those of the treatments with chemical fertilizer alonerespectively; nitrogen recovery rates in the application of the organic-inorganic mixedfertilizers were 5.5%～26.8%,8.2%～18.0% and 15.7%～38.7% higher than those of thetreatments with chemical fertilizer alone respectively.3 The application of organic-inorganic mixed fertilizers decreased the nitrate contentof the spinach by 28.7% and increased Vc by 18.9% compared with the application ofchemical fertilizer alone; Phosphorus and potassium uptake and the protein of rice inorganic fertilizer and organic-inorganic mixed fertilizer treatments were higher than inchemical fertilizers alone to a different degrees. Compared with the application of chemicalfertilizer alone, the organic-inorganic mixed fertilizer treatments decreased the nitrate by34.5%, and increased the ratio of soluble sugar to organic acid in tomato by 139%.4 Soil mineral N and soil microbial biomass C of the organic fertilizers andorganic-inorganic mixed fertilizers treatments were 2.32%～88.9% and 6.02%～38.2%higher than those of the treatments with chemical fertilizer alone respectively during theharvest time of crops. Application of the organic-inorganic mixed fertilizers could better synchronize the soil nitrogen supply with the requirement by crops and thus, greatlyimprove the soil nitrogen supply, and maintain a good model of soil mineral nitrogen forthe requirement by the crops.