中性紫色土施氮对小麦氮素吸收利用及产量和品质的影响

Effect of N Application on N Utilization and Yield-Quality of Wheat in the Neutral Purple Soil

为给西南地区小麦高产优质栽培中合理施氮提供依据，以西农麦1号为材料，在西南地区有代表性的中性紫色土上，研究了施氮对小麦氮素吸收利用及产量和品质的影响。结果表明。施氮在0～225kg／ha范围内，随氮肥用量的增加，小麦对氮的吸收量、籽粒粗蛋白质含量、籽粒产量和茎叶干重都显著增加，但氮的收获指数和氮肥的农艺效率却呈下降趋势。小麦各处理氮肥利用率平均为39．6％，以施纯氮75kg／ha水平最高。施氮对改善小麦的品质作用明显，其中籽粒淀粉含量以施纯氮量150kg／ha时最高。

We studied the effects of N fertilizer（NF） applications on N absorption and quality of wheat in the representative neutral purple soil of southwest China. The results indicated that when the N ap plication increase within the range of 0～225 kg/ha absorption of nitrogen, the crude protein content of grain, grain yield and stem-leaf yield of wheat will grow tremendously, while the agronomic efficiency and harvest index of nitrogen fertilizer show downtrend. All these prove that N aborbed is mainly contained in stem-leaf, and the removal and burning of straws would cause more N loss. The average utilization rate of NF is 39.6%, among which N application of 75 kg/ha gains the highest was gained. N application would remarkably improve wheat quality, the starch content of wheat grain is highest when NF application is 150 kg/ha.