Abstract: In 2011 and 2012, a split-plot design experiment was carried on the effects of row spacing ratio（RS/IS） on yield and top three leaves of super high-yielding late rice Wufengyou T025 and Ganxin 688 in the same planting density of 31.20×104 hille/hm2. The results indicated that the yield of RS/IS 2.0 and RS/IS 2.8 of Ganxin 688 were significant higher than that of RS/IS 5.0 and RS/IS 1.3 in no nitrogen condition, while the yield of RS/IS 5.0  and RS/IS 2.0 were significant higher than that of RS/IS 2.8 and RS/IS 1.3 in nitrogen condition. The yield of RS/IS 1.3 of Wufengyou T025 were significant higher than that of RS/IS 5.0 and RS/IS 2.8 in no nitrogen condition, while the yield of RS/IS 5.0 were significant higher than that of RS/IS 2.0 and RS/IS 1.3  in nitrogen condition. In nitrogen condition, RS/IS 5.0 and RS/IS 2.0 improved total amount of nitrogen accumulation and apparent nitrogen utilization, and RS/IS 5.0 decreased nitrogen demand of grain. Whether nitrogen application or not, the basic angle, stretch angle and leaf length of top three leaves of two rice cultivar in RS/IS 2.0 were small.

Key words: rice, super high yield, row spacing ratio, nitrogen rate, top three leaves, yield

摘要： 2011和2012年，采用再裂区设计，以超高产晚稻淦鑫688和五丰优T025为材料，在31.20万丛/hm2密度下，研究了行/株距比对不同品种产量和上部三叶形态特征的影响及两者的关系。结果表明，淦鑫688不施氮时，RS/IS（行株距比值）为2.0和2.8的处理产量显著高于比值为5.0和1.3的处理；在施氮时，RS/IS为5.0和2.0的处理产量显著高于2.8和1.3的处理。五丰优T025不施氮时的产量表现为RS/IS为1.3的处理显著高于5.0和2.8的处理；而在施氮时表现为RS/IS为5.0的处理显著高于2.0和1.3的处理。施氮时，RS/IS为2.0的处理提高了氮素积累总量和氮肥表观利用率，而RS/IS为5.0的处理降低了籽粒需氮量；不论施氮与否，两个品种在RS/IS为2.0时，倒1至倒3叶的基角、开张角和叶长较小。

关键词: 水稻, 超高产, 行/株距比, 施氮量, 上部三叶, 产量