东北龙胆的受精作用及其胚和胚乳的发育(Ⅱ)

Fertilization and The Development of Endosperm and Embryo of Gentiana manshurica ·K

东北龙胆的胚囊发育属于蓼型。珠孔受精。花粉管可通过破坏一个助细胞进入胚囊,也可在助细胞与胚囊壁之间进入胚囊。花粉管进入胚囊后释放出的两个精子分别与卵细胞及次生核融合,形成合子及初生胚乳核。受精作用属于有丝分裂前配子融合类型。胚乳发育为核型。当胚发育到4—6个细胞时,在胚囊珠孔瑞的游离核之间先形成细胞壁。细胞壁的形成是以自由壁的方式从珠孔端到合点端自外向内进行。胚的发育属于茄型。

The development of embryo sac belongs to polygonum type.Fertilization is porogamous.The pollen tube can enters into the sac by destroying one of the synergid and may enters the embryo sac between the synergid and embryo sac wall.After the pollen tube released, two sperms fuse comparely with the egg cell and the secondary nucleus forming the zygote and the primaryendosprm nucleus.The fertilization of Gentiana manshurica.belongs to premitotice type of syngamy.The endosperm is of the nuclear tyPe.The free cell wall for mation occurs first in the micropylar end when the embryo is 4—6 celled stage, then to the chalazal end and the center.The embryogeny belongs to the soland type.