大青杨花粉母细胞减数分裂及其发育

Meiosis of Pollen Mother Cells and Pollen Development of Populus ussuriensis

在温室(10～20℃)水培条件下,对大青杨花粉母细胞减数分裂及花粉发育过程进行了研究,结果表明:大青杨完成孢母细胞到四分体发育大约需要120h;减数分裂过程中最关键而复杂的前期Ⅰ大约占整个减数分裂进程60%的时间;当染色体从中期Ⅰ向两极迁移时,有明显落后的染色体,中期Ⅱ分裂相具有大量平行纺锤体和垂直纺锤体;大青杨花粉母细胞减数分裂与其雄花芽和花药形态有着密切关系,可从花芽外部形态变化判断花粉母细胞减数分裂进程。

An experiment was conducted to study the meiosis of pollen mother cells and pollen development of Populus ussuriensis under the condition of water culture in greenhouse. Results indicate that the meiosis of pollen mother cells of P. ussuriensis takes approximately 120 hours from sporoblast to tetrad at temperatures ranging from 10 to 20 degrees C. The prophase I is the most critical and complex stage of meiosis, which accounts for 60% of the cell cycle. The lagged chromosomes were observed at metaphase Ⅰ , and the paralleled and vertical spindles were observed at metaphase Ⅱ. It suggests that there is a close relationship between meiosis stage and morphology of male flower bud and anther, thus flower-bud morphology could be used to detemline the meiosis stage.