【摘要】 在小麦超高产栽培条件下,研究了氮肥不同追施时期、追施量对籽粒产量及植株生理特性的影响。结果表明,超高产小麦施氮量以240kg/hm²,基追比例5∶5为宜,追氮量过少或过多均不利于进一步提高小麦产量。氮肥不同追施时期对小麦产量也有不同的影响,小花雌雄蕊分化期（N₃）和药隔形成期（N₅）追肥可明显改善植株后期光合性能,降低叶片气孔阻力,并使植株体内保持高水平的保护酶活性,降低后期细胞膜脂过氧化水产,延缓植株衰老,从而促进籽粒的形成与发育,显著提高了籽粒产量。更多还原

【Abstract】 Effects of different nitrogen application on yield and plant physiological characteristics of winter wheat were studied under the super-high-yielding conditions. The results indicated that the application rate, 240 kg/ha, with base fertilization 50% and application 50% atjointing stage, was suitable for getting super-high grain yield. Too much or too little applicationof nitrogen might be unsuitable for making further improvement on wheat yield. Different effectson wheat yield and plant physiological characteristics were also obtained among different nitrogenapplication stages. Nitrogen application at stages of pistil-stamen formation and tetrad formationmarkedly increased photosynthetic ability and activities of SOD and POD of plant leaves, and alsodecreased stomatal resistance and membrane peroxidation level in later period of plant senescence,thus promoted grain filling and increased grain yield significantly.更多还原