高温诱导银白杨花粉染色体加倍研究

以银白杨为试验材料，在掌握小孢子母细胞减数分裂规律的基础上采用高温处理诱导花粉染色体加倍，对不同处理温度和处理持续时间在不同减数分裂时期的诱导效果进行了研究。结果表明：温室水培条件下，银白杨完成小孢子母细胞减数分裂大约需3~4d，不同时期和花药颜色变化有相关性；高温诱导银白杨2n花粉的最佳时期是中期Ⅰ，处理条件为36℃持续4h，最高2n花粉百分率39.6%，平均2n花粉百分率32.75%。高温处理后导致银白杨散粉延迟，相对于同一环境条件下的正常花芽散粉晚大约2~3d, 且花粉量很少。

POLLEN CHROMOSOME DOUBLING UNDER HIGH TEMPERATURE IN Populus alba L.

Techniques of high temperature-induced pollen chromosome doubling in Populus alba L. were studied based on observation of its meiotic process. The results showed that the meiotic process of pollen mother cells lasted for 3~4 d, and there was a relationship between the meiotic stages and color of anthers. The best stage for high temperature-induced pollen chromosome doubling was metaphase I. Frequency of 2n pollen was up to 39.6% at treatment of 36℃ for 4h, and the mean frequency of induced 2n pollen was 32.75%. Anther dehiscence was delayed owing to the effect of high temperature treatment. The dehiscence of treated anthers was 2~3d later than that of the untreated anthers, and just little pollen was collected from the treated anthers.