不同土壤肥力下施氮量对小麦产量和品质的影响

为探究氮肥在不同土壤肥力条件下对小麦的增产提质效应，以强筋小麦品种丰德存麦5号和中筋小麦品种百农207为供试材料，分别在三个地点设置0、180 、240和300 kg·hm^-2 四个施氮水平，研究了不同施氮量对冬小麦籽粒产量和品质的影响。结果表明，地点、品种和施氮量均对小麦产量有显著影响，其中地点的影响最大，其次是施氮量，品种最小。在高肥力麦田，施氮量为180 kg·hm^-2时产量最高，中高肥力麦田和低肥力麦田均以施氮量为240 kg·hm^-2时产量最高。不施氮肥条件下，品质指标以高肥力麦田较高，低肥力麦田最低，表明基础肥力高有利于改善小麦品质。施用氮肥均显著提高了小麦籽粒中的蛋白质含量、蛋白质产量、沉淀值和湿面筋含量，延长了形成时间和稳定时间，各试验点表现一致。利用主成分分析将小麦品质性状转化为蛋白质因子和面粉粉质因子，结果表明，在低肥力麦田，施氮量对蛋白质因子的增强效应较大，在中高肥力麦田，施氮量能均衡提高蛋白质因子和粉质因子；在高肥力麦田，施氮量对小麦粉质因子的增强效应较大。不论土壤肥力高低，均以施氮量为240 kg·hm^-2时小麦品质性状最优。

Effects of Nitrogen Rates on Wheat Yield and Quality under Different Soil Fertility Regimes

In order to investigate the effect of nitrogen fertilizer on grain yield and quality of winter wheat under different soil fertility conditions,the wheat cultivars Fengdecunmai 5 with strong gluten and Bainong 207 with medium gluten were used as experimental materials. Four nitrogen(N) application rates, including 0,120,240 and 300 kg·hm^-2, were applied at three sites to study the effect of different nitrogen application rates on grain yield and quality of winter wheat. The results showed that location, variety and nitrogen application rate had significant effects on the wheat yield, among which the effect of location was the greatest, followed by nitrogen application rate.The greatest grain yield was obtained at the N application rate of 180 kg·hm^-2 in the high fertility field, and at the rate of 240 kg·hm^-2 in the medium-high fertility and low fertility wheat fields, respectively. Without any chemical N fertilization, the grain quality indices were higher in the high fertility field than those in relatively lower fertility fields, indicating that high basic fertility might be beneficial to improve wheat quality. In all locations, N fertilizer application significantly increased grain protein content, protein yield, wet gluten content, and the sedimentation value of wheat flour, and prolonged the dough development time and dough stability time. According to principal component analysis, the grain quality indices were classified into two categories:the protein factor and the flour factor. N application rate greatly enhanced the protein factor in the low fertility field and the flour factor in the high fertility field, respectively.While in the medium-high fertility field, N application increased both the protein and flour factors.Regardless of the soil fertility levels, the best wheat quality was achieved at the nitrogen rate of 240 kg·hm^-2.