Abstract: Using japonica rice varieties with different plant types, studies were made on canopy properties in relation to dry matter production and yield. The results show that varieties responsiveness to nitrogen supply varied with plant types, and there were significant differences in the canopy development and the rate of dry matter production among varieties with different plant types. The more was the nitrogen supply, the more the differences of declining rate of leaf area after heading would be, and the less would be the differences of increasing rate of leaf area before heading among varieties with different plant types. The LAI at the heading stage had a significant quadratic regression relationship with grain yield and the rate of dry matter production after heading. The results also indicate that the LAI leading to maximum grain yield was basically consistent with the LAI conductive to maximum rate of dry matter prodriction, and that grain yield was positively corelated with the rate of dry matter production after heading.

Key words: Japonica rice, Plant type, Leaf area index, Dry matter production, Yield

摘要： 对不同株型粳稻品种的冠层特征与群体物质生产和产量的关系进行了研究。结果表明，品种的株型不同，对肥力的反应不同，冠层发展动态和干物质生产速度亦有明显差异．表现为随着肥力水平的提高，不同株型品种同抽穗前叶面积增长速度的差异减小，抽穗后叶面积衰减速度的差异增大。抽穗期的LAI与抽穗后群体干物质生产速度和产量之间呈二次曲线回归关系，获得最高产量的最适LAI与获得最大干物质生产速度的最适LAI基本上是一致的，抽穗后群体干物质生产速度与产量之间亦呈现出极显著的正相关。

关键词: 粳稻, 株型, 叶面积指数, 冠层, 干物质生产