一个自我不相容的系统解释了雄性植物中雄性高频率的原因
Pierre Saumitou-Laprade1, Philippe Vernet, Christine Vassiliadis
1Laboratoire de Génétique et Evolution des Populations Végétales, UMR CNRS 8016, Université des Sciences et Technologies de Lille-Lille 1, 59655 Villeneuve d'Ascq CEDEX, France. pierre.saumitou@univ-lille1.fr
Science (New York, N.Y.)
|March 27, 2010
概括
稳定的androdioecy,在自然界中很少见,是维护在Phillyrea angustifolia的自我不相容性组. 这种系统允许雄性对所有雌性动物进行授粉,抵消它们的生殖劣势.
科学领域:
- 进化生物学是进化生物学.
- 植物生殖策略 植物生殖策略
- 性系统 性系统
背景情况:
- 雄性和雌性体的性系统Androdioecy很少见,理论上要求雄性生育雌性体的两倍以上的后代.
- 橄家族 (Oleaceae) 呈现的androdioecy的频率高于理论预测.
- Phillyrea angustifolia是Oleaceae家族中的一种物种,在其中观察到androdioecy.
研究的目的:
- 研究维护Phillyrea angustifolia.androdioecious种群中高雄频率的机制.
- 测试假设,在雌雄性动物中自我不相容性群体有助于androdioecy的稳定性.
- 了解生殖优势如何抵消男性在这种性系统中面临的不利因素.
主要方法:
- 现场观测和人口调查的Phillyrea angustifolia.
- 对自然种群中的交配模式和花粉流的分析.
- 在雌雄性个体中对自我不相容性群体的评估.
主要成果:
- 在Phillyrea angustifolia中,雌雄性动物只属于两个不同的自我不相容性群体之一.
- 由于自我不相容性,每个雌雄性动物只能受精所有潜在花粉接受者的大约一半.
- 男性,缺乏自我不相容性,可以授粉所有的雌雄性动物,与雌雄性动物相比,他们的授粉成功率实际上翻了一番.
结论:
- 两性异性动物分为自我不相容的群体是维护Phillyrea angustifolia中高男性频率的关键因素.
- 这种生殖隔离机制抵消了男性失去女性功能的固有劣势.
- 这些发现为这种物种和可能是Oleaceae家族中的其他物种观察到的稳定androdioecy提供了新的解释.
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