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用水培和盆栽试验的方法研究了根系形态、吸收 Ｎ Ｏ－３ 的动力学参数 Ｖｍ ａｘ、 Ｋｍ 和生长速率对小麦品种（系）间吸氮量差异的影响。用水培方法测定的根系重量、总吸收表面积、活跃吸收表面积和 Ｎ Ｏ－３ 吸收动力学参数 Ｖｍ ａｘ、 Ｋｍ （以下统称为根系生理学指标）具有显著的品种（系）差异，且能很好地解释水培条件下吸氮量的品种（系）差异，即在低氮条件下， Ｋｍ低（对 Ｎ Ｏ－３ 亲和力高）的品种（系）吸氮量高；在高氮条件下 Ｖｍ ａｘ 高、根系发达的品种（系）吸氮量高。同时也能较好地解释盆栽试验中拔节期吸氮量的品种（系）差异，但它们与拔节后吸氮量的关系较差，可能原因是对氮的吸收还受生长速率（对氮素的需求量）的反馈调控。在播种—拔节、拔节—开花、开花—成熟期，不同品种（系）的吸氮速率与生长速率呈显著或极显著正相关。从吸氮规律上分析，总吸氮量高的品种（系）具有开花后吸氮量高的特点，并对影响开花后吸氮量的因素进行了分析
The effects of root morphology, kinetic parameters Vm ax, Km of absorbing N O-3 and growth rate on the difference of nitrogen uptake among wheat cultivars (lines) were studied by hydroponics and pot experiment. The root weight, the total absorption surface area, the active absorption surface area and the Nm-3 absorption kinetics parameters Vm ax, Km (hereinafter collectively referred to as root physiological indices) determined by the hydroponic culture method have significant varieties (lines) differences and can well Explain the differences in nitrogen assimilation varieties (lines) under hydroponic conditions, that is, under low nitrogen conditions, low Km (high N O-3 affinity) varieties (lines) nitrogen uptake high; under high nitrogen conditions Vm ax High, root developed varieties (lines) high nitrogen uptake. At the same time, it also can explain the differences of varieties (lines) of nitrogen absorption at jointing stage in pot experiment, but they have a poor relationship with nitrogen uptake after jointing. The possible reason is that the absorption of nitrogen is also affected by the growth rate The demand for feedback) regulation. In the sowing - jointing, jointing - flowering, flowering - mature stage, different varieties (lines) of nitrogen absorption rate and growth rate was significant or very significant positive correlation. According to the regular pattern of nitrogen uptake, the varieties with high total nitrogen uptake had the characteristics of high nitrogen uptake after flowering, and the factors affecting the nitrogen uptake after flowering were analyzed