重穗型水稻株型特性研究

Studies on the Characteristics of Rice Plant with Heavy Panicle

目的对重穗型杂交籼稻的一些主要的株型因子及其与产量和产量构成的关系进行研究。方法以15个不同穗重型籼稻品种为材料,随机区组设计。结果重穗型品种的LAI比中、轻穗型品种有适当降低,但齐穗后其LAI和高效叶面积的衰减较慢,高效叶面积率、比叶重、粒叶比有显著提高。重穗型品种上部3叶的长度、宽度、厚度和面积均显著大于中、轻穗型品种,且它们均与每穗粒数、实粒数、单穗重、籽粒产量呈显著正相关;重穗型品种剑叶叶角小而挺直,倒2、3叶叶角顺次适当增大;重穗型品种的株高有所增加,上部3叶叶位均有所提高,尤其是剑叶。结论这种较优的叶层结构利于形成较为理想的受光姿态,提高光能利用率,是重穗型品种的特性及其理想株型因子配置。

[Method] Using 15 indica rice varieties with different panicle weight, some plant type characteristics in heavy panicle type of hybrid rice （HPT） and their relation to yield and its components were studied. [Result] The leaf area index （LAI） of HPT varieties was lower than that of medium panicle type （MPT） and light panicle type （LPT） varieties, but its decreasing rate of LAI and efficient LAI after heading was slower and had much higher percentage of efficient LAI, specific leaf weight and ratio of grain to leaf area （cm^2） in comparison with MPT and LPT varieties. The length, width, thickness and area of top 3 leaves of HPT varieties were significant larger than those of MPT and LPT varieties, and these components of top 3 leaves were significantly and positively correlated with the number of spikelets and filled grains, grain weight per panicle and grain yield. The flag leaf in HPT varieties was erect with sorrow leaf angle, and their leaf angle of 2nd and 3rd leaf from top increased in sequence. The plant height of HPT varieties were higher than that of MPT and LPT varieties, and their leaf site of top 3 leaves also increased in sequence. Therefore, HPT varieties had an ideal plant type and could increase the utilization efficiency of sunlight energy. [Conclusion] The ideal plant type characteristics and their adjuncts for HPT varieties were proposed in this paper.