欧洲黑杨花粉母细胞减数分裂观察及其不同步性分析

Meiosis of Pollen Mother Cells and Their Asynchrony in Populus nigra L.

以欧洲黑杨的雄花枝为材料,采用温室切枝水培和醋酸洋红染色制片法,观察花粉母细胞减数分裂进程及其与花芽发育外部形态的关系。结果表明:(1)欧洲黑杨花粉母细胞的减数分裂进程快慢与温度高低关系密切;(2)减数分裂发生时其花芽的外部形态发育没有明显变化;(3)花粉母细胞减数分裂不同步性突出,同一花药内的花粉母细胞处于不同的减数分裂时期,且同一花芽尖端发育明显滞后于中部和基部;(4)减数分裂过程中有少量的核仁异常现象,虽观察到较多平行纺锤体现象,但未发现天然2n花粉。该研究结果揭示了欧洲黑杨减数分裂的遗传变异规律,为诱变育种、倍性育种以及分子水平的进一步研究奠定了细胞学基础。

The meiosis of pollen mother cells and their asynchrony in flower buds of Populus nigra L.were studied with water culturing detached floral branches in greenhouse and aceto-carmine staining.The results were as follows：（1）There were a close relationship between stages of meiosis in P.nigra L.and the temperature.（2）There were no obviously phenotypical changes in flower buds when the meiosis of pollen mother cells occurred.（3）Meiosis of pollen mother cells in P.nigra L.was asynchronous and the growth of the top end of a flower bud extremely lagged behind the other part.（4）The abnormal nucleoli were not seen frequently.Many paralleled spindles at metaphase Ⅱ were observed but little 2n pollen were found after pollen had dispersed.The results of this research will lay a cytogenetical basis for further studies.