摘要
本工作主要应用石蜡切片方法,对芝麻大孢子发生和雌配子体的发育进行了观察,同时初步观察了淀粉粒以及减数分裂过程中胼胝质的变化。结果表明:①芝麻为倒生胚珠,单珠被,薄珠心;②大孢子母细胞直接来源于孢原细胞,减数分裂形成线形排列四分体,合点端一个为功能大孢子,胚囊发育为蓼型,成熟胚囊中见不到反足细胞;③在胚囊发育过程中,胚囊两侧的珠心表皮细胞解体,胚囊紧贴于由珠被内表皮转变而成的珠被绒毡层之下。合点端珠心细胞转变为承珠盘;④减数分裂前期,大孢子母细胞无胼胝质壁,二分体、四分体也只有横向的胼胝质壁,而侧壁则无;⑤淀粉粒最初出现在子房壁和胎座中,并不断向胚囊提供多糖类物质。
The ovules of Sesamum indicum L.are anatropous,unitegmic and tenuinucel- late.with a hypodermal archesporical cell which develops directly as the megaspore mother cell.Megasporogenesis is normal,and a monosporic eight-nucleate embryo sac of the most common polygonum type develops from the chalazai megaspore.The antipodals are short- lived and degenerate when the two polars fuse forming a big secondary nucleus.During the development of female gametophyte the inner epidermal cells of the integument develop into the integumentary tapetum,and the cells of the chalazal region abutting the embryo sac dif- ferentiate to form the hypostase.
关键词
芝麻
大孢子发生
雌配子体发育
seasme(Sesamum indicum L.)
megasporogenesis
development of female gametophyte
