光温敏核雄性不育小麦BS366花粉母细胞减数分裂的细胞学研究

Studies on Meiosis of Pollen Mother Cells in Photoperiod-temperature Sensitive Genic Male Sterile Wheat Line BS366

要以小麦光温敏核雄性不育系BS366为材料,采用卡宝品红压片法研究花粉母细胞减数分裂的细胞学变化。结果表明:不育环境下的BS366花粉母细胞减数分裂过程中染色体和细胞形态异常现象较多。染色体异常主要表现为:染色体落后,染色体桥、染色体散乱排列,微核、染色体分离不同步。细胞形态异常表现为:二分体时期细胞质不完全分裂,细胞板不平整;四分体时期子细胞大小不一。花粉母细胞减数分裂后,异常四分体的比例为62.88%;成熟花粉粒中败育率为89.5%。推测减数分裂期间异常的染色体行为以及细胞形态可能是影响花粉育性降低的重要原因。

In this paper, cytological studies were conducted on pollen mother cells meiosis of photoperiod temperature sensitive genic male sterile wheat line BS366 by using carbol fuchsin and chromosome squash technique. Some abnormalities of meiosis were observed in stertile condition. They were lagged chromosomes, chromosome bridges, scattered chromosomes and micronucleus. During meiosis Ⅱ, chromosome segregations were not synchronous. At dyad stage, the cell plate was out of flatness and the cell was incomplete divided. At tetrad stage, the tetrad cells were not coincident with each other in size. The percentage of abnormal tetrad was 62.88%, and 89.5% of matured pollen grains were sterile. Abnormal chromosome behavior and cell morphology during meiosis may be the important reason for fertility reduction of photoperiod-temperature sensitive genic male sterility wheat pollen.