中文摘要：

剑叶角度是构成水稻理想株型的重要指标和影响水稻产量的重要因素。通过水稻剑叶角度与氮营养效率的关系研究,为水稻塑造理想株型和提高氮营养效率提供理论依据与技术途径。试验采用盆栽土培法,以不同年代的9个典型稻种资源为材料,设置不施氮（0kg/hm^2尿素）、正常施氮（240kg/hm^2尿素）和高施氮（480 kg/hm^2尿素）3个施氮水平,于水稻灌浆期测量剑叶角度、各器官含氮量和土壤含氮量,进行剑叶角度与氮营养效率间的相关分析与函数拟合。结果表明,不同水稻品种的剑叶角度和氮营养效率存在显著的基因型差异,且随施氮水平而异。剑叶角度随施氮量的增加而急剧增加,不施氮下的基因型间差异明显小于正常施氮和高施氮。剑叶角度与氮利用效率、土壤氮生产力、植株氮生产力和氮收获指数呈显著负相关,不同氮营养效率间存在极显著正或负相关。氮利用效率、土壤氮生产力、植株氮生产力和氮收获指数随剑叶角度呈显著的对数递减,顺序为植株氮生产力〉氮收获指数〉氮利用效率〉土壤氮生产力。因此,在生产上可根据水稻剑叶角度来预测氮营养效率,并以其为依据实时地调控氮肥运筹来实现氮营养的高效利用。

英文摘要：

Flag leaf angleofrice was important component of the ideal rice architecture, and the important affecting factor of gaining rice yield. The relationships between flag leaf angles of variouss rice germplasms and their nitrogen nutrition efficiencies were studied to provide the theoretical foundations and technological approaches for establishing ideal rice architecture and improving nitrogen nutrition efficiencies. In this study, nine typical rice germplasms bred in different years were used as the experimental materials in pot experiments and grown under low nitrogen （0 （480 kg/hm^2 urea） levels. During kg/hm^2 urea）, medium nitrogen （240 kg/hm^2 urea） and high nitrogen mature stage, flag leaf angle, nitrogen contents of each organ in rice germplasms and soil were determined to analyze the correlations and fit function on the flag leaf angle and their nitrogen nutrition efficiencies including nitrogen utilization efficiency（NUE）, nitrogen recovery efficiency（NAE）, nitrogen translocation efficiency（NTE）, nitrogen productivity of soil（NPS）, nitrogen productivity ot plant （NPP）, nitrogen flow efficiency （NFE）, nitrogen harvest index（NHI）. The results showed that flag leaf angles and nitrogen nutrition efficiencies of various rice germplasms existed significant genotypic differences, which varied with different nitrogen levels. Flag leaf angles increased rapidly with the increasing of nitrogen, their genotypic differences among various rice germplasms under low nitrogen were obviously lower than those under medium and high nitrogen. The correlations between flag leaf angle and HUE, NPS, NPP or NHI were significantly negative, their descending deceased with logarithm function and the order of NPP 〉 NH1 〉 NUE 〉 NPS; and the correlations between flag leaf angle and NAE, NTE and NFE were not significantly negative,but the correlations among nitrogen nutrition efficiencies were markedly significantly negative or positive. So, nitrogen nutrition efficiencies of rice were predic