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This paper studied the effect of nitrogen and potassium on Biyu pumpkin’s growth and development, yield, quality, absorption and distribution of nutrition element. In the meantime, we also studied the morphological and physiological characteristics changes of pumpkin. Analyzed by computer, we determined the optimizations of pumpkin fertilizer, and offered the scientific theoretical foundation for applying fertilizer rationally in pumpkin. The main results were as follows:1. N, K affected pumpkin’s growth. In a certain range, plant growth increased when the quantity of fertilizer increased. But if the quantity were too much, the growth would decrease.2. N, K affected pumpkin’s photosynthesis ability. When the ratio of N and K is reasonable, chlorophyll content and photosynthetic rate are high. The period of high light effect is long. Photosynthetic rate in later period of corm vigorous growth stage deceased slowly and photosynthetic matter accumulated more.3. N, K affected the pumpkin’s ability of utilizing nutrition. When usage of N and K is reasonable, the absorption amount of N, K is increased. The amount which distributed to fruit was also augmented , which helped to improve economic coefficient.4.N and K affected the quality of pumpkin. If the proportion of N and K is reasonable, content of protein, soluble sugar, Vc, are high.and Nitratecontent is low If usage of N and K are below 19kg/667m2N 39.28kg/667m2, quality would increase with the increase of fertilizer. If used too much fertilizer, quality would decrease. The fertilizer plan of highest quality is N 17.825kg/667m2, K2O 36.92kg/667m2.5. N and K affected the yield of pumpkin. In this experiment, if usage of N and K are below 37.125kg/667m2kg/667m\ 159.74kg/667m2, yield would increase with the increase of fertilizer. But if used too much fertilizer, yield would decrease. The fertilizer plan of yield over 5000Kg/667m2 is N 26.33-42.08 kg/667m2, K2O 27.08-65.92 kg/667m2
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