银杏雌配子体形成及颈卵器发育的细胞学研究  

Cytological Studies on the Formation of Female Gametophyte and Development of Archegonia in Ginkgo Biloba

作　　者：吉成均[1] 杨雄[1] 李正理[1] 

机构地区：[1]北京大学生命科学学院

出　　处：《北京大学学报（自然科学版）》1999年第4期496-502,共7页Acta Scientiarum Naturalium Universitatis Pekinensis

基　　金：国家自然科学基金

摘　　要：银杏（ＧｉｎｋｇｂｉｌｏｂａＬ．）的功能大孢子经１０多次游离核分裂，形成约２０００个核后，向心地形成细胞壁。雌配子体中游离核之间细胞壁还未完全形成时，在其近珠孔端表面可看到颈卵器母细胞发生。一个雌配子体中的颈卵器数目通常为２个，它们的发育最初不同步，以后逐渐趋向一致。在颈卵器的发育过程中，颈细胞和中央细胞的形态及结构都发生了较大的变化。颈卵器的２个颈细胞在受精前进行一次斜向分裂形成４个颈细胞，此分裂一般早于中央细胞的分裂，偶尔也可见颈细胞和中央细胞同时分裂。银杏雌配子体及颈卵器的发生与发育，和苏铁类植物比较，在演化程度上可能更为原始。Following approximately a dozen of multiple divisions of producing about 2000 n uclei, the cell wall of the female gametophyte of Ginkgo biloba began to for m centripedally. The archegonial initials could be distinguished from the perip heral cells at the micropyle end of the female gametophyte before the completion of the wall formation where the cell wall had reached the center of the gametop h yte. Usually there were two archegonia in a female gametophyte which developed a synchronously at first, and gradually developed in concert. Great structural and morphological changes in the neck cell and the central cell took place during t he archegonial development. The two neck cells of the archegonium divided to fo rm four neck cells before fertilization, this division happened prior to the div ision of the central cell, but at times they divided synchronously. The initiati on and development of archegonia in Gingko,compared with those of cycads, w ere liked to be more primitive at the evolutional level.

关 键 词：银杏 雌配子体 颈卵器 发育 细胞学 

分 类 号：Q949.640.5[生物学—植物学]