【目的】明确遗传背景相似、生育期相近的遗传群体水稻株高对氮素吸收利用效率的影响。【方法】在群体水培条件下,以遗传背景相似的染色体单片段代换系114个水稻株系为供试材料,依据株高将供试群体聚类分为A、B、C、D、E和F 6类,研究不同株高类型水稻产量、氮素吸收和利用的差异及其相互间的关系。【结果】(1)供试群体株高表现出差异较大但分布相对集中的特点;(2)随着株高的增加,不同类型水稻产量总体呈上升趋势,超高株系增幅更大;(3)随着株高的增加,不同类型水稻成熟期吸氮量呈明显上升趋势,在超高株高情况下表现更突出;(4)水稻成熟期总吸氮量可以从全株含氮率与干物质生产量、抽穗前吸氮量与抽穗后吸氮量、单位面积穗数与单茎(穗)吸氮量、生长日数与吸氮强度4个方面进行解析。随着株高的上升,干物质生产量、抽穗期吸氮量、单穗吸氮量、吸氮强度均表现为上升趋势,但植株含氮率、生长日数类型间无明显差异,A-E供试群体范围内单位面积穗数和抽穗后吸氮量也无明显变化,F显著高于其他类型。进一步分析表明,各吸氮量构成因子对成熟期吸氮量的作用表现为:干物质生产量大于含氮率,抽穗前吸氮量大于抽穗后吸氮量,单穗吸氮量大于单位面积穗数,吸氮强度大于生长日数;(5)在A-E供试群体范围内,氮素干物质生产效率、氮素籽粒生产效率变化较小,氮素收获指数总体呈下降趋势,F类供试群体这3个指标除氮素干物质生产效率略低外,均显著低于其他类型。可见,株高在正常变化范围(A-E类)内与增加到超高(F类)后,株高的改变对氮素吸收、氮素利用的影响有一定的差异。因此,不同株高范围内氮素营养改良的重点应作出相应的调整。【结论】在所有株系内增加株高使水稻成熟期氮素吸收能力显著提高,但氮素收获指数、氮素籽粒生产效率有所降低,在株高150 cm以上的在超高株系下这种趋势更突出。表明不同株高范围内,株高对氮素吸收、氮素利用的影响有所不同,为此在水稻氮高效遗传改良时应充分考虑到这个因素。 【Objective】 The objective of this study is to clarify the effects of plant height on nitrogen absorption and utilization efficiency of genetic groups with similar genetic backgrounds and similar growth stages. 【Method】 Under the condition of population hydroponics, 114 rice lines with similar genetic backgrounds were used as test materials, and the test groups were divided into A, B, C, D, E and F 6 to study the differences in yield and nitrogen uptake and utilization of different plant types and their relationships with each other. 【Result】 (1) The plant height of the tested population showed the characteristics of large difference but relatively concentrated distribution; (2) With the increase of plant height, the yield of different types of rice showed an overall upward trend, (3) With the increase of plant height, the amount of nitrogen uptake in different types of rice during the maturity stage showed a clear upward trend, especially in the case of ultra-high plant height; (4) Rate and dry matter production, nitrogen uptake before heading and nitrogen uptake after heading, spike number per unit area and nitrogen uptake by single stem (spike), growth days and nitrogen absorption intensity were analyzed. With the increase of plant height, dry matter production, nitrogen uptake at heading, nitrogen uptake per panicle, and nitrogen absorption intensity all showed an upward trend, but there was no significant difference in the nitrogen content and the number of growing days between plants. There was no significant change in spikes per unit area and nitrogen uptake after heading in the population range, F was significantly higher than other types. Further analysis showed that the effect of nitrogen uptake factors on the amount of nitrogen uptake during maturity was as follows: the dry matter production was greater than the nitrogen content, the nitrogen uptake before heading was greater than the nitrogen uptake after heading, and the nitrogen uptake by single ear was larger than unit area (5) Within the range of AE test population, the NUEQ production efficiency, the NUE production efficiency changed little, the N harvest index overall showed a downward trend, and the F test In addition to slightly lower production efficiency of nitrogen dry matter, the three indicators of the group were significantly lower than the other types. It can be seen that the effect of plant height changes on nitrogen uptake and nitrogen utilization is somewhat different when the plant height is within the normal variation range (A-E class) and increases to ultra-high (F class). Therefore, the focus of nitrogen nutrition improvement in different plant height should be adjusted accordingly. 【Conclusion】 Increasing the plant height in all the lines increased the nitrogen absorption ability of rice at maturity stage, but the nitrogen harvest index and the efficiency of nitrogen seed production decreased. Under the condition that the plant height is above 150 cm, This trend is even more prominent. The results showed that the plant height had different effects on the nitrogen uptake and nitrogen utilization in different plant height. Therefore, this factor should be fully taken into account in the genetic improvement of nitrogen efficient in rice.