【摘要】 在油菜整个大田生长期间,分期镜检全株生长点的花原基分化。结果表明:茎级愈高,花芽分化开始愈迟,同一茎轴上,各分枝开始花芽分化的次序则因枝位而异。在本试验条件下,抽苔前的油菜,一、二级分枝花原基的分化速率较慢,分化数量较少,但主茎及其上部一、二级分枝在此时分化的花原基多数能开花结实。当油菜进入抽苔至开花期,各级花原基分化的速率最快,分化数量亦最多,但大多数均不能开花结实。因此,在长江下游的类似生态条件下,当油菜抽苔前适当促进花芽分化,并在抽苔期控制花芽的发生,对增加油菜产量可能具有重要的意义。更多还原

【Abstract】 A gross anatomical study of flower bud differentiation in a whole rape plant (Brassica napus L.) was made throughout its growing period. The main results obtained are summarized as follows:1. On the same plant,the higher the branch grade, the later the flower bud differentiation started.On the branches of grade No. 1 flower bud differentiation started from below upward and from above downward with the terminal node and the highest node of one third of the total nodes from the base as starting points.On the branches of grades No. 2-5 flower bud differentiations were basipetal.2. On the branches of grades No.land 2 flower bud differentiation proceeded at the early growing stage,at a low rate of speed and with a small quantity of floral primordia.At the elongation stage, flower bud differentiation of all branch grades proceeded, at a high rate of speed and with a large quantity of floral primordia.3. Most of the floral primordia differentiated on the main stem and its branches of grades No. land2before the elongation stage blossomed and bore fruit, whereas the floral primordia differentiated at the elongation stage scarcely bore fruit. Consequently, measures should be taken to promote flower bud differentiation at the early growing stage and check it at the elongation stage. This might be beneficial to the increase of the number of silique and thereby the raising of seed yield.更多还原