播期和施氮量对冬小麦氮代谢及子粒蛋白质含量的影响

为了阐明播期变化与施氮量对冬小麦氮代谢及蛋白质的影响,采用裂区设计,研究播期和施氮量对冬小麦花后茎叶氮含量、积累量和子粒蛋白质含量的影响。结果表明,适度晚播可以提高冬小麦茎、叶的氮含量、氮素积累量和子粒蛋白质含量。与不施氮肥相比,施用氮肥可以显著增加冬小麦不同生育时期地上部氮素累积量,且随着施氮量的提高,茎、叶的氮积累量也表现为先升高后降低的趋势。在同一播期条件下,子粒蛋白质含量以施氮150和225kg/hm ²的处理最高,说明适宜的施氮量能改善子粒品质。分析播期与施氮量对子粒蛋白质含量的作用程度可知,施氮量是引起冬小麦子粒蛋白质含量变化的主要因素,作用程度占66.85%。在本试验条件下,兼顾冬小麦花后茎叶氮素代谢及产量,实现高子粒蛋白质含量的推荐播期是10月11日,施氮量为150kg/hm ²。研究结果可为山西省冬小麦调优栽培提供理论和技术支持。

Effects of Sowing Date and Nitrogen Fertilizer Rate on Nitrogen Metabolism and Kernel Protein Content of Winter Wheat

In order to clarify the effects of sowing date and nitrogen application rate on nitrogen metabolism and protein of winter wheat, the nitrogen content, accumulation and grain protein in stems and leaves were investigated after the flowering stage with split plot design. The results showed that the moderately late sowing could increase the nitrogen content, nitrogen accumulation and grain protein content in stem and leaf of winter wheat. Compared with the nitrogen rate (0kg/hm ²), the nitrogen accumulation content increased along with the nitrogen application obviously and it improved firstly, and then declined with the increase of nitrogen rate. On the same sowing date, the grain protein content reached to the highest with the nitrogen application of 150kg/hm ² and 225kg/hm ², and it indicated that the appropriate nitrogen application amount could achieve the best grain quality. Moreover, the nitrogen application was proved to be the main factor to determine the grain protein content as the effectiveness of nitrogen application to grain protein could account for 66.85%. Therefore, considering the nitrogen metabolism, grain protein content in the leaf and stem, yield of winter wheat, the recommended sowing date and nitrogen application rate were October 11 and 150kg/hm ² in current situation. The results can provide theoretical and technical support for winter wheat planting optimization in Shanxi province.