生物多样性 ›› 2012, Vol. 20 ›› Issue (3): 386-390.  DOI: 10.3724/SP.J.1003.2012.05041

所属专题: 传粉生物学:理论探讨与初步实践 传粉生物学

• 研究报告 • 上一篇    下一篇

雌全同株植物三脉紫菀花期偏雄的个体大小依赖的性别分配

戈星月, 朱璧如*(), 廖万金   

  1. 北京师范大学生物多样性与生态工程教育部重点实验室, 北京 100875
  • 收稿日期:2012-02-02 接受日期:2012-03-20 出版日期:2012-05-20 发布日期:2012-05-09
  • 通讯作者: 朱璧如
  • 作者简介:*E-mail: biruzhu@bnu.edu.cn
  • 基金资助:
    国家自然科学基金委创新研究团队项目(31121003)

Male biased sex allocation with plant size in gynomonoecious Aster ageratoides

Xingyue Ge, Biru Zhu*(), Wanjin Liao   

  1. Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Beijing Normal University, Beijing 100875
  • Received:2012-02-02 Accepted:2012-03-20 Online:2012-05-20 Published:2012-05-09
  • Contact: Biru Zhu

摘要:

经典的虫媒传粉植物个体大小依赖的性别分配模型通常预期: 分配给雌性功能的资源比例将随着个体大小的增大而增加; 但一些研究表明,花期个体大小依赖的性别分配模式表现出随个体大小增大而偏雄的趋势。我们以植株高度衡量个体大小, 从花和花序两个水平上研究了雌花、两性花同株植物三脉紫菀(Aster ageratoides)花期个体大小依赖的性别分配策略。随着植株高度的增大, 植株产生的头状花序数量增加, 表明三脉紫菀投入到繁殖的资源不是固定不变的, 而是随个体大小增大而增加的。在花和花序水平上, 繁殖资源在雌雄性别功能之间的分配均表现为随个体大小的增大而更偏雄的模式, 即花粉/胚珠比增加, 产生花粉的两性花占两性花和雌花总花数的比例升高。这些结果与花期个体越大、性别分配越偏雄的预期一致。花期更偏雄的性别分配可能有助于植物在花期通过输出花粉提高雄性适合度, 从而实现个体适合度的最大化。

关键词: Aster ageratoides, 雌全同株, 花粉/胚珠比, 单胚珠花, 大小依赖的性别分配

Abstract

Classic size-dependent sex allocation models for animal-pollinated plants predict that female allocation increases with plant size. However, some studies have shown a male biased size-dependent sex allocation at flowering stage. We investigated the size-dependent sex allocation strategies within flower and inflorescence in gynomonoecious Aster ageratoides within two naturally-occurring populations in which hermaphroditic and female flowers occur in the same individual. At the flowering stage, male biased size-dependent sex allocation has been observed at both flower and inflorescence level. The pollen/ovule ratio ranged from 750 to 5,250, with a mean of 2,757.14± 206.635, and increased significantly with plant height in one of the populations. At the inflorescence level, the male allocation, which was measured by the proportion of hermaphroditic flowers, increased with plant height in both populations. These results are consistent with the expectation of male biased size-dependent sex allocation at flowering stage, through which A. ageratoides may maximize fitness by enhancing pollen dispersal.

Key words: Aster ageratoides, gynomonoecy, pollen/ovule ratio, single-ovule flower, size-dependent sex allocation