温敏核不育小麦可育和败育花粉的超微结构观察

Ultrastructural Observation of Fertile and Sterile Pollen Grains of A Thermo-sensitive Genic Male-sterile Wheat

温敏核不育小麦可育与不育花粉超微结构观察结果显示:可育花粉小孢子分裂形成二胞花粉后,营养细胞中的大液泡形成一些单膜小液泡,导致大液泡体积减小,然后通过增加液泡内含物,使大液泡转变为细胞质基质。伴随着营养细胞大液泡消失,细胞质中开始积累淀粉粒并逐渐增加。不育花粉在小孢子分裂之前发育正常,但在形成的二胞花粉中出现异常,营养细胞中有自体吞嗜泡形成并融入到大液泡中,结果大液泡不消失,细胞质基质不增加,营养细胞中没有积累淀粉粒,最终花粉败育。该种小麦雄性不育花粉败育时间和败育结构特征的确定为进一步深入研究其花粉败育机制打下基础。

The fertile and sterile pollen grains ofthermo-sensitive male sterile wheat （Triticum aestivum L.） were observed using electron microscope to find the structural feature of sterile pollen grains. Before microspore division, the structure of microspore of sterile line was normal. The earliest abnormal phenomenon in sterile pollen grains appeared in bicellular pollen grains： in fertile line, after microspore divided to form bicellular pollen grains, the big vacuole in the vegetative cell became small size by forming some small vacuoles with single member. Then the big vacuole filled some content and became cytoplasm matrix. Following the big vacuole decomposing in vegetative cell, some starches grains accumulated in the pollen. In sterile pollen grains, microspore could divide to form a bicellular pollen. The vegetative cell, however, formed some autophagosomes moving into big vacuole, which resulted in the big vacuole of vegetative cell not decomposing but enlarging. The bicellular pollen kept the big vacuole all the time. Then, the pollen cytoplasm decreased and pollen aborted. The determination of abortion time and abortion structure of this male sterile wheat makes a foundation for further more researching its abortion mechanism.