四分孢子

通过检查小孢子母细胞减数分裂染色体行为和四分孢子行为，分析了热激或低温诱导产生2n花粉的细胞遗传学机理。

The cytogenetic mechanism of 2n pollen formation after heat-shock or low temperature treatment was determined on the basis of the behavior of meiotic chromosomes and sporads during microsporogenesis .

四分孢子四面体形，孢质分裂同时型；

Arrangement of microspores is tetrahedral and cytokinesis is simultaneous type .

四分孢子的显著特征是细胞核和高尔基体呈活跃状态。

The characteristics of tetrad was that the nucleus and Golgi bodies being in the active state .

但是减数分裂过程能够完成，并且四分孢子的败育率较低。

But even so , meiosis can still carry out from start to finish , and the frequency of abortive tetraspores was low .

四分孢子体卡拉胶的粘度在秋、冬季较高，雌配子体的粘度无季节变化。

The carrageenans derived from tetrasporic plants showed the marked seasonal variation in viscosity , which appeared to be high in autumn and winter .

[2]孢子母细胞减数分裂形成四分孢子，进入四分体时期。

And the protoplasts fused and intrude among the sporocytes . [ 2 ] The sporocytes form tetraspores by meiosis and enter the tetrad phase .

结果表明：不育系和保持系都能正常进行减数分裂，绒毡层细胞无明显差异，形成了正常的四分孢子。

The results showed that microsporogenesis could process normally and there was no difference in the tapetal cell between 8A and 8B lines before tetrad stage .

[5]孢子周壁在真蕨目植物中普遍存在，它是在四分孢子分离后，逐层沿离心方向在外壁表面形成的，周壁来源于绒毡层细胞或孢子囊壁细胞。

It is formed on the surface of exospore in centrifugal direction after the separation of tetraspores . It is derived from the tapetal cells and sporangial wall cells .

四分孢子间的横壁存在胼胝质.功能大孢子缺少胼胝质，退化的大孢子细胞壁积累大量胼胝质.4.大孢子母细胞减数分裂期间，侧壁一直缺少胼胝质。

Callose appeared in the newly formed transverse walls seperating the tetrad cells , was absent in the cell wall of the fuctional megaspore , and was abundant in that of the degenerated megaspores . ( 4 ) There was no callose in the side walls of megasporocyte during meiosis .

孢原细胞平周分裂形成一个周缘细胞和一个造孢细胞，造孢细胞直接发育成大孢子母细胞，四分体大孢子呈线形排列，它们均可成为功能大孢子；

The sporogenous cell functioned directly as megaspore mother cell . The tetrad of megaspores was linear in arrangement , and every megaspore might be functional .

细胞质分裂之后，每个四分体外被透明的细胞膜，四分孢子之间有孢子套膜将其分离。

After cytokinesis , each of the tetraspores was enveloped with a transparent plasmolemma and covered by coat membranes which separate the tetraspore from each other .