Effect Of NPK Fertilizer Combination On Yield And Qualit Of Potato

Early spring temperature in the Guanzhong region of Shaanxi province is low, later spring temperature rose rapidly. It was a relatively short period of time for potato tuber formation and bulging. However, spring planting table stock potato plays an important role for the local vegetable supply. Therefore, to improve the quality and yield of spring potato has great significance. The reasonable NPK fertilization application is the key measure to improve the yield and quality, which had less research in the Guanzhong region. This study used the “Zhaodabai” as material with five NPK fertilization treatments(CK, K1, K2, K3, K4) at the experimental field of Northwest A&F University during 2013-2014. The growth development, yield, quality and storage quality were researched at the growth stage of potato in hope of providing a reasonable NPK fertilization for the spring planting table stock potato in Guanzhong region. The main results were as follows:(1) The reasonable NPK fertilization greatly improved the agriculture characters and physiological traits.The effects of different treatments(CK、K1、K2、K3、K4) on agriculture characters and physiological were different. All the K1, K2 and K3 treatments increased the plant height, stem diameter, branch number. In addition, the K2 treatment was the most prominent than others. The K4 treatment compare with CK treatment, both the plant height and branch number of potato were descended significantly. Also, the stem diameter of K4 treatment was significantly less than the CK and K2 treatment. The main stem number of the K4 treatment was more than other treatments but the branchs were finespun. Adding NPK fertilization properly can improve the chlorophyll content, net photosynthetic rate of potato leaves at tuber bulging stage, plant dry matter content, which the promotions of K2 treatment were significant than CK treatment.(2) The reasonable NPK fertilization can improve the yield of potato.Compared with CK treatment, both of the K1 and K2 treatment improved the big-middle potato ratio, maximum tuber weight, tuber number and tuber weight per plant. What’s more, the treatment K1 and K2 can improve the tubers yield of potato, which increased by 7.33%~10.05%. The K2 treatment had a highest yield deduction amount 28626.67kg/hm2 which increased 2613.34kg/hm2 significantly than CK. When increased the NPK fertilization, the yield components and yield of K3 treatment had no significant difference with CK treatment. The yield components and yield of K4 treatment were less than CK, which decreased significantly compared with K2 treatment.(3) The reasonable NPK fertilization can improve the quality of potato.The K2 treatment can significantly increase the content of dry matter, starch, soluble protein, vitamin C and decrease the content of reducing sugar, thus improving the quality of potato. Compared with CK treatment, increasing NPK fertilization(K3 and K4 treatment) can not improve the quality of potato. Compared with K2 treatment, the content of dry matter, starch, soluble protein and vitamin C of K4 treatment decreased significantly.(4) The effects of different NPK fertilization on storage quality were different.During the 60 d storage, the content of dry matter, starch and vitamin C decreased smallest with K1 treatment, which maximum decreasing by K2 treatment. But, the increase of reducing sugar content by K2 treatment was smaller than other treatments.