朝鲜蒲公英花粉败育的细胞学研究

A cytological observation on those factors affecting pollen abortion of Taraxacum coreanum

为从细胞水平探明朝鲜蒲公英花粉败育的原因,通过卡宝品红染色和石蜡切片法观察花粉母细胞减数分裂行为及雄配子发育过程。结果表明:花粉母细胞减数分裂过程中存在大量落后染色体、染色体桥、断片、染色体分离不同步以及不均等分裂等异常情况,染色体行为异常导致四分体时期出现二分体、三分体、含微核的异常四分体以及多分体等现象;朝鲜蒲公英成熟花粉为3–细胞型,存在多核的异常花粉粒。综合分析,认为朝鲜蒲公英花粉母细胞减数分裂异常和雄配子的生殖核异常发育是导致花粉败育的主要原因。

Meiosis behaviors of pollen mother cells and development process of male gametes were observed by carbol fuchsin stainin and paraffin sectioning method for exploring the cytological mechanisms on pollen abortion of Taraxacum coreanum Nakai.. The results showed that there were much many abnormal cases in the process of meiosis, such as lagging chromosomes, chromosome bridges, fragments, unsynchronized segregation and uneven division. Many micronucleus, dyads, triads, tetrads and polyads come into being during tetrad phase induced by the abnormal behaviors of chromosomes. Mature pollen of T. coreanum mainly belongs to three-cell type and partially hybridizes with abnormal generative cells. In general, abnormal meiosis in the process of pollen mother cell and abnormal development of generative nucleus of male gametes were the main reasons for the pollen abortion of T. coreanum.