水稻剑叶角度与氮素营养效率的关系

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（0 kg/hm²尿素）、正常施氮（240 kg/hm²尿素）和高施氮（480 kg/hm²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。

The Relationships Between Flag Leaf Angles of Various Rice Germplasms and Their Nitrogen Nutrition Efficiencies

In this study, pot experiments were conducted to explore the relations between flag leaf angle and nitrogen nutrition efficiencies of rice. 9 rice varieties were grown under low nitrogen (0 kg/hm2 urea), medium nitrogen (240 kg/hm2 urea) and high nitrogen (480 kg/hm2 urea) levels, and flag leaf angle and nitrogen nutrition efficiencies including nitrogen utilization efficiency (NUE), nitrogen recovery efficiency (NAE), nitrogen translocation efficiency (NTE), nitrogen productivity of soil (NPS), nitrogen productivity of plant (NPP), nitrogen flow efficiency (NFE), nitrogen harvest index (NHI) were measured at mature stage. The results showed that flag leaf angle and nitrogen nutrition efficiencies of different varieties existed significant genotypic difference, which varied with different nitrogen levels. The correlations between flag leaf angle and NUE, NPS, NPP and NHI were significantly negative, their curve deceased with logarithm and the order of their descending was NPP > NHI > 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.