油菜单株分化的花芽数达千朵左右,而无效角果竟占一半。近年来,我们对无效角果的成因及解决途径进行了初步的试验和调查。成因根据多点调查,油菜无效角果的多少与单株营养条件的好坏、田间密度的大小,和后期的气候条件都有直接的关系。表现是: 一、在同一单株上无效角果随着分枝部位的下移而增加,一般二次分枝最多,一次分枝次之,主花序最少(表1)。在一个花序上,阴角主要发生在顶部,中下部较少。从生育阶段看,油菜蕾、花的脱落率以盛花期最高,约占57％;终花期次之,占31％;始花期最低,占12％。以此现象分析,认为 The number of flower buds per plant of the rapeseed lines is about one thousand, while the invalid ones account for half. In recent years, we have carried out preliminary tests and investigations on the causes and solutions of ineffective pods. Genesis According to the multi-point investigation, the number of inedible rapeseed rape has a direct relationship with the nutritional status of the plant, the density of the field, and the later climatic conditions. The performance is: First, in the same plant invalid fruit plover with the downward movement of branches increased, the general secondary branches up, followed by a branch, the least main inflorescence (Table 1). On one inflorescence, female horns occur mainly at the top and less in the middle and lower parts. From the fertility stage, rape buds, flower exfoliation rate to the peak flowering, accounting for about 57%; the second flowering terminal, accounting for 31%; flowering lowest, accounting for 12%. According to this phenomenon analysis, think