Abstract: Microtubule patterns during the megasporogenesis of polyembryonic rice strain APⅣ and normal monoembryonic rice variety IR36 were studied by using PEG preparation, immunofluorescence and confocal laser scanning microscopy. No difference in changes of microtubule patterns during megasporogenesis between APⅣ and normal variety IR36 was observed. Microtubules exhibited random array in archesporial cell, and became asymmetric distribution along micropyle chalazal end. A new microtubule array of "rotary sharpness" was found in the megasporocyte at leptotene. There were dramatic changes of microtubule distribution in the megasporocyte at diakinesis, which appeared a nuclear envelope associated MTOC (microtubule organizing center). Radical microtubules displayed around nuclear envelope of dyad and tetrad. Only a few random microtubules were observed in the megaspore.

Key words: rice, polyembryony, megasporogenesis, microtubule

摘要： 运用PEG包埋制片、间接免疫荧光和共聚焦激光扫描显微术，对多胚水稻品系APⅣ和正常单胚水稻品种IR36大孢子发生期间微管骨架组织变化进行观察，发现两份材料大孢子发生所经历的阶段一致，每个阶段微管骨架均具特点：孢原细胞微管为随机状排列，大孢子母细胞在进入减数分裂前微管呈现极性分布，细线期微管呈独特的“旋状”排列，终变期出现明显的微管组织中心，二分体和四分体核周围主要为辐射状微管，功能大孢子内存在少量随机状微管。

关键词: 水稻, 多胚现象, 大孢子发生, 微管