| 摘要: |
| [目的]测试多枝柽柳花粉活力和柱头可授性在开花散粉后的动态变化规律,为进一步研究其有性繁殖提供基础资料.[方法]分别在新疆吐鲁番和阜康选取10株健康多枝柽柳植株,定株观察其的开花动态和花后柱头的形态变化,并用MTT法检测其花粉活力(每次用3朵花)和柱头可授性(每次用20朵花的柱头).[结果]多枝柽柳在06:30～08:00开花,单花花期只有1 d;花粉活力随生境不同而有所差异,多枝柽柳花药刚散粉时花粉活力最高,达84%以上,24 h后活力迅速下降;不同花期、不同生境条件下植株的花粉活力下降速度一致,其活力可持续48 h;柱头可授性的持续时间在吐鲁番春花期和阜康春花期、夏花期之间不存在差异(34 h),而吐鲁番夏花期的柱头可授性仅持续24 h;柱头呈现白色时具有可授性.[结论]多枝柽柳花粉具有高活力的时间与柱头具有强可授性的时间正好吻合,说明其适应自花传粉的机制,柱头在花朵开放前已具有可授性,有支持异交而降低自交的倾向. |
| 关键词: 多枝柽柳 开花动态 花粉活力 柱头可授性 |
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| 基金项目:国家自然科学基金，国家科技支撑计划 |
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| Study on floral dynamics,pollen viability and stigma receptivity of Tamarix ramosissima |
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| Abstract: |
| 【Objective】 The study was to provide a basis for the research on sexual reproduction of Tamarix ramosissima.【Method】 Ten healthy plants were selected at Turpan and Fukang respectively,Pollen viability(Three flowers were used each time) and stigma receptivity(Stigmas of twenty flowers were used each time) of T.ramosissim a were estimated by MTT and the flowering dynamics and morphology of stigma were investigated based on the methods of labeled individuals.【Result】 T.ramosissima blossomed at 06:30-08:00 in daytime,the life span of one flower being only 1 day.The pollen viability of T.ramosissim was different according to different habitats,and was the highest at the beginning,and its viability declined sharply after 24 h.The decline rate of pollen viability was not different according to different flowering periods and different habitats and the 1ife span of all of them were about 48 h.The stigma receptivity was not different among the spring flowering periods of Turpan and Fukang and the summer flowering period of Fukang（34 h）.The stigma receptivity of summer flowering period of Turpan lasted only 24 h.Stigmas had receptivity when they were white.【Conclusion】 Pollen viability was higher when stigma had receptivity,indicating T.ramosissima had adapted to the mechanism of self pollination. Stigmas had higher receptivity before blooming which showed a tendency to promote xenogamy and minimize geitonogamy. |
| Key words: Tamarix ramosissima floral dynamics pollen viability stigma receptivity |
