南京林业大学学报(自然科学版) ›› 1981, Vol. 5 ›› Issue (04): 64-74.doi: 10.3969/j.jssn.1000-2006.1981.04.006

• 研究论文 • 上一篇    下一篇

梓树(Catalpa ovata)胚胎发育的研究

樊汝汶   

  1. 南京林产工业学院林学系
  • 出版日期:1981-12-18 发布日期:1981-08-18

A STUDY ON THE EMBRYOLOGICAL DEVELOPMENT OF CATALPA OVATA

Fan Ruwen   

  1. Department of Forestry
  • Online:1981-12-18 Published:1981-08-18

摘要: <正>1.花粉母细胞的胞质分裂是在减数分裂之后同时发生的。四合花粉为四面体形。花粉于二细胞时散落。 2.单一的皮下孢原不经过任何分裂,直接行使胚囊母细胞的功能。 3.胚囊为单孢8-核型。 4.观察到双受精过程。 5.胚乳的形成与Maurtzon(1935)认为的Catalpa型不同。不同点是:初生胚乳核分裂形成胚乳原始细胞、合点吸器和珠孔吸器,后二者是非常短命的,由胚乳原始细胞形成胚乳,由合点区细胞解体形成次生合点吸器。 6.休眠合子随着吸器的解体迁移到合点端,而后随着胚乳的迅速伸展进入胚囊中部。

Abstract: 1. Simultaneous cytokinesis in the mother pollen cells follows meiosis and the tetrads are tetrahedral. Pollen grains are 2-celled when shedding.2 . There is a single hypodermal archesporium, which functions directly as the mother embryo-sac cell.3 . The embryo-sac is of the monosporic eight-nucleate type.4 . Double fertilization has been observed.5. The formation of endosperm differs from the Catalpa-type reported by Mauritzon. The difference consists in the fact that the primary endosperm nucleus divides and forms the endosperm initial cell, the chalazal haustorial and the micropyle haustorial, the latter two being very ephemeral, that the endosperm initial cell divides into the endosperm tissue and that the chalazal end cells disintegrates and forms the second chalazal haustorial.6 . When the haustorium degenerates, the dormant zygote migrates to the chalazal end. Then following the extension of the endosperm tissue, the dormant zygote rapidly enters into the median of the embryo-sac.