我国水稻矮化育种工作自五十年代取得突破后,至今已20多年了,育种水平不断提高。多年来,我们从事丛化育种的研究,亦已获得初步成果,育成一些新的高产品种类型,在生产上应用推广,经济效益显著。现就丛化育种的理论和实践作一些探讨。一、新品种模式的设想及其依据农作物的干物质有90—95％是由光合作用初次合成的有机物质构成的。栽植密度适当的水稻群体,由于其单位面积内营养器官的增加(包括总蘖数的增加和相应叶面积的增加)而能充分利用地力,更好地发挥同化器官的光合作用,从而制造和积累更多的营养物质;当群体的密度未超出或未显著超出合理的范围时,则在其他综合栽培措施的配合之下,可获 Since the breakthrough of rice dwarf breeding in China in the 1950s, it has been more than 20 years now, and the level of breeding has been continuously raised. Over the years, we have engaged in the study of plexus breeding. We have also obtained initial achievements, bred a number of new high-yielding varieties and applied them to the production to promote their economic benefits. Now plexus breeding theory and practice for some discussion. First, the idea of ​​a new variety model and its basis 90-95% of the dry matter of crops is composed of the first synthesis of organic matter by photosynthesis. Due to the increase of vegetative organs per unit area (including the increase of total number of tillers and the corresponding increase of leaf area), the population of rice with suitable planting density can make full use of soil fertility and better exert the photosynthesis of assimilating organs to manufacture and accumulate More nutrients; when the density of the population does not exceed or is not significantly beyond the reasonable range, then under the cooperation of other comprehensive cultivation measures,