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[目的]为了明确温敏雄性不育系小麦BNS雄性败育的细胞学机制。[方法]采用醋酸洋红染色对温敏雄性不育系小麦BNS花粉母细胞减数分裂和小孢子发育过程进行细胞学观察,采用浓度1%I2-KI溶液染色法进行花粉育性统计。[结果]BNS不育系在减数分裂过程中异常,中期Ⅰ出现染色体滞后现象;二分体时期细胞质分配不均匀,染色体靠边,没有在细胞中央;四分体时期子细胞大小不一,其子细胞存在落后染色体,有的二分体经过第2次分裂没有形成4个子细胞,而是分成3个子细胞;小孢子发育过程中观察到单核靠边期,未能发育到双核期和三核期,还出现空孢现象;开花期的花粉彻底败育。而扬麦13能形成正常的二核期和三核期,花粉可育。[结论]减数分裂过程中出现的异常行为是导致BNS花粉败育的原因之一。单核期是其败育的关键时期。
[Objective] The purpose of this study was to determine the cytological mechanism of male sterile BNS in wheat cultivars with thermo-sensitive male-sterile lines. [Method] Cytological observation of meiosis and microspore development of BNS pollen mother cells in thermo-sensitive genic male sterile wheat was carried out by magenta staining, and the pollen fertility was calculated by 1% I2-KI staining. [Result] The chromosome aberration in BMS was abnormal during metaphase Ⅰ, chromosomal lagging occurred in metaphase Ⅰ. The cytoplasm was unevenly distributed during chromosome dying, and the chromosomes were not in the center of the cell. The size of the daughter cells in the tetrad stage was different There are sub-chromosomes behind the daughter cells, and some bisexual second division did not form four daughter cells, but divided into three daughter cells; microspore development observed during the single-core margin, failed to develop to the dual-core and the trinuclear Stage, also appeared Holosporium phenomenon; flowering of pollen completely abortion. While Yangmai 13 can form normal two-nuclear and three-nuclear, pollen fertile. [Conclusion] Abnormal behavior during meiosis was one of the reasons leading to pollen abortion in BNS. The mononuclear phase is the critical period of abortion.