油茶花芽分化及雌雄配子体发育的研究

Flower bud differentiation and development of male and female gametophytes in Camellia oleifera

以‘湘林1号’油茶为试材,运用石蜡切片法对其花芽分化及雌雄配子体发育进行解剖观察,并对其花芽发育与外部形态的相关性进行分析。结果表明：（1）‘湘林1号’花芽分化大致可以划分为6个时期：即前分化期、萼片形成期、花瓣形成期、雌雄蕊形成期、子房与花药形成期和雌雄蕊成熟期。（2）‘湘林1号’的花药为4室;药壁发育属于基本型;腺质绒毡层;小孢子母细胞减数分裂中胞质分裂为同时型,四分体排列多为正四面体;开花前7~9 d花粉成熟,成熟花粉为2—细胞花粉粒。（3）胚珠为倒生胚珠,薄珠心,具双层珠被;大孢子母细胞经减数分裂形成二分体,其中只有合点端的大孢子具功能,经过3次有丝分裂形成7细胞8核胚囊,胚囊发育为葱型。（4）在花芽发育过程中,不仅雌雄性细胞的形成之间有比较稳定的对应关系,而且它们与其外部形态特征之间也有着相对稳定的关系。根据它们的时序性对应关系,可以通过花芽或花的外部形态特征来对其内部的性细胞发育进程进行即时判别。

Cytological observation on the development of female and male cells of Camellia oleifera ＇Xianglin No.1＇ was carried out by the method of paraffin sectioning,and the correlation between flower bud differentiation and its external morphology was analyzed.The results show that：（1） The development of flower bud differentiation could be divided into 6 stages： pre-differentiation,sepal formation,petal formation,stamen and pistil formation,ovary and anther formation,and stamen and pistil maturation;（2） ＇XL No.1＇ had four ventricles in each anther;the development of the anther wall belonged to the basic type;glandular tapetum;the meiosis in the microspore mother cells belonged to the simultaneous type and the microspores were arranged in a tetrahedron shape in the tetrads;pollen matured in seven to nine days before blooming;The ripened pollen was of 2-cell type;（3） The ovule was anatropous ovule,nucellus thin,with a double integument;the megasporocyte underwent meiotic division,giving rise to two dyad cells,only the megaspore at chalazal end had biological function,forming 7 nuclear and 8 embryo sacs that underwent 3 mitosis as the onion-type embryo sac.（4） During the process of development,not only the formation of androecium and gynoecium had stable corresponding relations,but aslo they all corresponded with the external morphology.According to the corresponding relations in time sequence,the development process of the interior sexual cell could be identified by the external morphology.