【摘要】 以毛新杨（Ｐｏｐｕｌｕｓｔｏｍｅｎｔｏｓａ×Ｐ．ｂｏｌｅａｎａ）为材料，在掌握小孢子母细胞减数分裂过程的基础上，对花粉染色体加倍中减数分裂的有效处理时期以及作用持续时间进行了研究，结果表明：（１）经秋水仙溶液处理所获得的花粉中均有一定比例的形态较大的花粉，最高可达８８％。这种大花粉经花粉染色体检查为２ｎ＝３８，且均能正常萌发。（２）一般只要是在水培４０ｈ左右，花药由淡绿色转为绿黄色以后且未变红前，也就是由细线末期到终变期之前处理，均能取得较好的加倍效果。（３）在有效处理时期内，处理次数与花粉得率也有一定的相关性，考虑２ｎ花粉比率及花粉量得率，处理次数以３～５次，每次间隔５～７ｈ为宜。更多还原

【Abstract】 The effective meiosis period and treating duration of pollen chromosome doubling were researched, based on mastering the meiosis law of microsporocyte of Populus tomentosaP.bolleana. The results indicated (1) A certain proportion of the bigger pollen grains could be gotten from the male flower buds induced by cochicine solution,the highest proportion was up to 88% and these bigger pollen grains contained 38 chromosomes by microscopic examination, and could normally germinate by both the common medium and the vivi\|fertilization;(2) Generally, so long as the buds were cultured with water for 40 hours, the colour of anther changed from light green to yellowish\|green, not to get red, i.e. during the period from the end of bouquet stage to the beginning of diplotene, in which the best doubling effect could be obtained. (3) During the suitable treating duration, there was correlation between the treating frequency and the amount of obtained pollen, considering the 2n pollen ratio and the amount of obtained pollen, the better treating frequency was from 3 to 5 times, the interval between two treatments should be 57 hours.更多还原