【摘要】 为系统探明椪柑无核发生的机制,以无核椪柑新品种丽椪2号和普通有核椪柑为试材,对雌雄配子体的育性和亲和性进行了观察。结果表明,丽椪2号花粉发芽率、花粉染色活力和花粉粒数量等与有核对照存在显著性差异,属于低育型花粉。丽椪2号花粉母细胞在减数分裂期染色体行为发生了异常,出现较高频率的染色体链及少部分的染色体环和落后染色体。授以高育性的雪柑花粉后,丽椪2号仍能形成无核果。切片观察发现,丽椪2号胚囊母细胞在四核期已完全退化。因此,胚囊高度败育是丽椪2号产生无核的主要原因。更多还原

【Abstract】 In order to explore the seedless mechanism of Ponkan(Citrus reticulata Blanco),new seedless Ponkan cultivar Lipeng No.2 and common seedy Ponkan cultivar were used as materials for observing fertility and compatibility of male and female gametophyte.Results showed that pollen germination rate,pollen stain-ability,pollen grain amount and so on had remarkable difference between the two cultivars and Lipeng No.2 pollen belonged to low-fertility type.Partial chromosomes happened abnormally during pollen mother cells meiosis,which included chromosome chain,chromosome loop,lagging chromosome and chromosome unequal distribution.Lipeng No.2 produced seedless fruit all the same when pollinated with Xuegan orange cultivar.Observation by paraffin section showed that Lipeng No.2 embryo sac mother cells were almost entirely degenerated during megasporogenesis.It is concluded that embryo sac sterility was the main reason for highly stable seedless characteristic of Lipeng No.2 cultivar.更多还原