松花菜小孢子发育的细胞学观察

Cytological Observation on Microspore Development of the Loose-curd Cauliflower Cultivar

以松花菜F1代杂交种为材料,分别观察自然发育和游离培养条件下小孢子的发育过程。结果表明,自然条件下,四分体释放小孢子后,单核小孢子经历2次分裂,从双核期到三核期,最后发育为成熟花粉粒,是配子体发育途径;在游离培养条件下,小孢子经过热激(33℃)处理后,发生均等分裂或者不均等分裂,之后经过一系列的细胞增殖,最终发育成为胚状体,小孢子发育途径是从配子体向胚胎发育转换的途径。同时发现,并不是所有发生了分裂和增殖的细胞都能形成胚状体,只有极少数小孢子最终形成正常胚。

Used the loose-curd cauliflower F1 hybrids as study material,microspore development process of in vivo was observed under natural development and free culture conditions,respectively.The results showed that under natural conditions,after the tetrad releases microspore,the mononuclear microspore undergoes two divisions,from binuclear to trinuclear stage,and finally develops into mature pollen grains,which is the way of gametophyte development.Under the condition of free culture,microspore undergoes equal or unequal division after heat shock treatment(33℃).After a series of cell proliferation,microspore eventually develops into embryoid.The microspore development pathway is from gametophyte to embryo.At the same time,it was found that not all cells that divide and proliferate can form embryoids,only a few microspores eventually form normal embryos.