Effects of Nitrogen Application Rates on Growth, Yield and Quality of Winter Potato

WEI Jianfeng; WEI Qiaoyun; LIANG Zhenhua; SONG Shuhui; WEI Dongping; LIANG He

Abstract：In order to determine reasonable nitrogen application rate for winter potato,a field experiment was conducted to investigate the effects of nitrogen application rate ( 0 , 80 , 160 , 240 kg/ha ) on the emergence ratio,dry matter accumulation,yield and quality of potato cultivar Favorite. The results showed that with the increase of nitrogen application rate,the seedling emergence ratio decreased;the dry matter accumulation of stalk first increased and then decreased,and reached the peak value when the nitrogen application rate was 160 kg/ha applied during tuber expanding stage to harvest stage;the dry matter accumulation of leaves,tuber and total amount increased,and reached the peak value when the nitrogen application rate was 240 kg/ha during tuber expanding stage to harvest stage;the commodity tuber ratio, commodity tuber yield and fresh tuber yield increased, and reached the peak value when the nitrogen application rate was 240 kg/ha,the treatment with nitrogen of 160 kg/ha was lower in order,and the fresh tuber yield of treatment with nitrogen of 240 kg/ha increased by 51 . 28% compared with the treatment without nitrogen fertilizer;the soluble sugar content,crude protein content,crude protein yield and starch yield of tuber increased,and reached the peak value when the nitrogen application rate was 240 kg/ha, followed by the treatment with nitrogen of 160 kg/ha. However,the yield traits and main quality traits of potato were not significantly different between the treatment with the nitrogen application rate of 160 kg/ha and the treatment with the nitrogen application rate of 240 kg/ha. Therefore, the optimum application rate of nitrogen for winter potato was 160 kg/ha in the present study.