摘要
在温室水培条件下对通辽杨（Populus simonii Carr．×P．nigra L,‘Tongliao’）花粉母细胞减数分裂进程及其染色体行为进行了研究。结果表明：（1）通辽杨花粉母细胞减数分裂与其雄花芽／花序外部特征和花药颜色有着密切关系，前期Ⅰ作为减数分裂过程中最关键而复杂的一个阶段，大约占整个减数分裂进程90％的时间；中期Ⅰ存在单价体，后期Ⅰ有落后染色体出现，表现出较强的遗传杂合性，而且中期Ⅱ平行纺锤体的出现与天然花粉中大花粉的存在之间可能有着一定的联系；（2）在通辽杨减数分裂过程中核仁数目存在1～8个的动态变化，这种现象可能与杨属植物古多倍性起源有关，并推测通辽杨染色体组内至少存在8对带有次缢痕的染色体；（3）在同一个花芽，同一个小花，乃至同一个花药中，往往能同时观察到5～9个不同的分裂相，这种减数分裂不同步性是通辽杨适应环境的一种进化表现，对其种群繁殖具有重要意义。
The meiosis and chromosome behavior of pollen mother cells in Populus simonii Carr, X P. nigra L. ‘Tongliao＇,which were hyroponically cultured in greenhouse, were studied. It was showed that （1） in Populus simonii Carr. × P. nigra L. ‘Tongliao＇ the meiosis of the pollen mother cells was closely related to external characters of male flower buds/inflorescences and the colors of anthers and in the meiosis prophase Ⅰ was the most critical and complex stage,accounting for 90% in time,there appeared univalents at metaphase Ⅰ and lagged chromosomes at anaphase Ⅰ ,indicating that the pollen mother cells had strong genetic heterozygosity and the appearance of paralleled spindles at metaphase Ⅱ was related to the presence of big pollen grains in natural pollens to certain extent; （2） In Populus simonii Carr. X P. nigra L. ＇ Tongliao＇ the nucleolus number varied between 1 and 8 in the meiosis of pollen mother cells and this phenomenon was probably related to ploidy origins in Populus L. plants,and the genome of Populus sirnonii Carr. × P. nigra L. ‘Tongliao＇ was supposed to have 8 pairs of chromosomes with constriction at least; （3） There were five to nine division phases simultaneously observed in the same flower buds and same flowerets and even in same anthers and this meiosis outasync was of important significance in population reproduction and propagation of the genus.
出处
《西北植物学报》
CAS
CSCD
北大核心
2006年第11期2231-2238,共8页
Acta Botanica Boreali-Occidentalia Sinica
基金
国家自然科学基金项目(30471407)
关键词
通辽杨
花粉母细胞
减数分裂进程
多核仁
杂合性
大花粉
Populus simonii Carr. × P. nigra L. ‘Fongliao＇
pollen mother cell
meiosis progress
polycaryon
heterozygosity
big pollen
