农业“八字宪法”中已经明确指出,合理密植是各种作物增产的中心环节。从高产出发,研究春油菜区的春播油菜在一定范围内、一定水肥条件下,适于高产的密植定额,无疑是当前生产实践中一个值得研究的课题。探讨油菜的密植定额,实质上是研究不同密度条件下,群体的动态变化与个体生长发育的相互关系。应当指出,正确处理群体与个体的关系,是研究各种作物丰产规律中的一个比较重要的内容,这是因为在不同密度条件下,由于单株营养面积的改变,个体的生长发育也必然相应地发生变化。例如,在高密度条件下,个体的营养面积减小,根、茎、叶和分枝等器官的生长状态,首先受到影响,由于营养器官发生量的变化,必然也就导致单株有效分枝数、角果数和粒数、粒重的变化,绝对值减小,就影响到单株生产力。因此,研究春油菜在不同密度条件下,群体与个体的关系,实质上也是探讨油菜主要经济性状,随着密度增加的变化规律。 It has been clearly pointed out in the “Character Constitution” of agriculture that close and reasonable planting is the central link in increasing the output of various crops. From the perspective of high yield, it is undoubtedly a worthy research subject in the current production practice to study the spring rapeseed in the spring rapeseed area within a certain range under certain water and fertilizer conditions. To explore the close planting quota of rapeseed is essentially to study the relationship between population dynamics and individual growth and development under different density conditions. It should be pointed out that the correct handling of the relationship between groups and individuals is an important part of the study on the laws of crop yield. This is because, under different density conditions, the growth and development of individuals must correspond to changes in the nutrient area per plant Changes have taken place. For example, under high-density conditions, the individual’s nutrient area is reduced, and the growth status of organs such as roots, stems, leaves and branches is affected first. As the amount of vegetative organs changes, this inevitably results in the effective branching of individual plants Number, number of pods and grain number, grain weight changes, the absolute value decreases, affecting the productivity of a single plant. Therefore, the study of spring rape under different density conditions, the relationship between groups and individuals, is essentially to explore the main economic traits of rape, with the increasing density of the law.