星星草受精作用及其胚与胚乳早期发育的观察

Observations on the Fertilization and the Early Development of Embryo and Endosperm in Puccinellia tenuiflora

利用常规石蜡切片法对星星草[Puccinelliatenuiflora(Griseb.)Scribn.etMerr.]受精过程及胚与胚乳的早期发育进行了观察,主要结论如下:(1)开花后2h,花粉管破坏1个助细胞,释放2个精子,精子呈逗点状。(2)开花后2～3h,2个精子分别移向卵细胞与极核。(3)开花后3～5h,精核分别贴附于卵细胞与极核的核膜上。(4)开花后5～10h,精核与卵核融合,雄性核仁出现,合子形成。(5)开花后5～6h,精核与极核融合,并出现雄性核仁,形成初生胚乳核,精核与极核的融合比与卵核融合要快。(6)开花后20h左右,合子分裂。(7)开花后8h,初生胚乳核分裂。(8)双受精作用属于有丝分裂前配子融合类型。(9)胚胎发育属于紫菀型,胚乳发育属于核型胚乳。

Observations of the processes of the fertilization and the early development of embryo and endosperm of Puccinellia tenuiflora by means of normal paraffin method are presented in this paper.The main results are as follows: (1) 2 hours after flowering,pollen tube destroys a syner-(gid),releasing two sperms.The sperms are phaseoliform in shape.(2) 2 to 3 hours after flowering,two sperms move to egg cell and the polar nucleus,respectively.(3) 3 to 5 hours after flowering,two sperm nuclei are nestled on the nuclear membranes of the egg nucleus and a polar nucleus respectively and simultaneously.(4) 5 to 10 hours after flowering,the membrane of one male nuclear and that of the egg nuclear are fusing,and a small male nucleolus appears in the egg nuclear after fusing,as is the symbol of the formation of zygote.(5) 5 to 6 hours after flowering,the male nucleus is fusing with the polar nucleus,and a small male nucleolus appears in the polar nucleus after that,as is the symbol of the formation of primary endosperm nucleus.The fusion of sperm nucleus with the polar nucleus is faster than that of it with the egg cell.(6) 20 hours after flowering,the zygote starts dividing.(7) 8 hours after flowering,the primary endosperm starts dividing.(8) The double fertilization is the type of Premitotic syngamy.(9) The embryogene coforms to the Asterad type and the endosperm genesis is of Nuclear type.