Abstract:

Abstract：Field experiments were conducted to study the effects of top-dressing nitrogen, phosphorus and potassium at different stages on yield and quality of potato in Wuxi and Chengkou county of Chongqing. The results showed that compared with conventional fertilization, stage N and K, split application of NPK treatments were effective to improve the yield of potato tubers. Among them, potato yield were increased range from 2.5% to 5.6 % in Wuxi and increased range from 1.4 % to 19.7% in Chengkou. Vc content of potato were increased in all fertilization treatments. The contents of starch，crude protein and phosphorus in potatos were decreased in all fertilization treatments. Changes of soluble sugar and potassium in potatos were inconsistent in two experiments.