祝光苹果小孢子发生和雄配子体的发育

The Development of Male Gamctophyte of Apple American Summet-Pcacmain

从花芽膨大至开花历时26天。开花前19—16天,幼叶与花序伸出期,小孢子母细胞进行减数分裂。小孢子发生为同时型。四分孢子多为四面体型。小孢子发育(中央期——靠边期)持续5天。开花前10——9天,花蕾分离,顶花花冠微露时,是小孢子第一次分裂的时期。2——细胞雄配子体充实期持续7—8天。开花前2—3天,2—细胞花粉粒发育成熟。生殖细胞的分裂在花粉管中完成。但也观察到生殖细胞在花粉粒中分裂、发育成3—细胞花粉粒的现象。

The stage from expansion of floral buds to blossom lasts 26 days.When the folioles and inflorescences appear faintly, 19- 16 days before blossom, microsporoeytes begin the stage of meiosis.The microsporogenesis belongs to the simultaneous type. The microspore tetrad is the tetrahedricspore.The development of micnospores (the central stage-stage in which the nucleus Lies in the edge of a cell) Lasts 5 days.When the flower buds separat and eorolla facrogenous flawers appear faintly. 10- 9 days before blossom, the microspores divide first time.The stage of full eontents of 2-celled mate gametophytes lasts 7- 8 days.The 2-celled pollen grains mature 3-2 days before blossom.The division of generative ceils completes in pollen tubes.It is observed that generative calls divide in pollen grains and develop into 3-celled pollen grains.