小果野蕉（Musa acuminate Colla）花粉母细胞减数分裂过程 异常的细胞学观察

香蕉是重要的热带水果，由于雄性不育、单性结实等原因导致其杂交育种困难。小果野蕉（Musa acuminate Colla）是现代香蕉栽培种的祖先之一，在理论研究和应用中有非常重要的地位。前期研究发现小果野蕉存在部分可育 花粉，但导致花粉活力下降的原因未知。为了探求导致小果野蕉花粉活力降低的细胞学原因，本研究通过亚历山大红 染色法对小果野蕉花粉活力进行检测，通过卡宝品红染色对小果野蕉花粉母细胞减数分裂阶段和小孢子发育阶段进行 观察。结果表明：小果野蕉花粉活力为 84.33%；小孢子发育阶段未见明显异常；正常四分体比例为 81.3%；花粉母细 胞减数分裂过程终变期、中期Ⅰ、后期Ⅰ、中期Ⅱ、后期Ⅱ均存在异常，比例分别为 8.8%、8.5%、7.6%、10.6%、12.1%。 因此，可能是部分花粉母细胞减数分裂异常导致小果野蕉花粉活力的降低。

Cytogenetic Analysis of Male Meiosis Defect in Xiaoguo Wild Banana (Musa acuminate Colla)

Banana is an important tropical fruit. But cross breeding of it is difficult due to male sterility and parthenocarpy. Xiaoguo wild banana (Musa acuminate Colla) is one of the ancestors of cultivated modern banana species, which plays an important role in theoretical research and application. Some vital pollens were found in Xiaoguo wild banana, but the reasons for the decrease of pollen vigor were unknown. In order to find out the cytological reasons, the pollen vitality was detected by Alexander red staining, the pollen mother cell and microspore were analyzed by fuchsin staining. The results showed that the pollen vitality was 84.33%, the microspore development stage did not shown obvious abnormity, the proportion of normal tetrad was 81.3%, and the ration of abnormal pollen mother cells in diakinesis, metaphase , anaphase , metaphase Ⅰ Ⅰ , anaphase Ⅱ Ⅱ was 8.8% and 8.5%, 7.6%, 10.6 % and 12.1% separately. Therefore, it is possible that the abnormal meiosis of some pollen mother cell leads to the decrease of pollen vitality in Xiaoguo wild banana.