生物多样性 ›› 2018, Vol. 26 ›› Issue (5): 519-526.DOI: 10.17520/biods.2018038

• 研究报告 • 上一篇    下一篇

新疆郁金香一居群个体性别7年的动态变化

王娟, 翟雅芯, 张爱勤*()   

  1. 新疆大学生命科学与技术学院, 乌鲁木齐 830046
  • 收稿日期:2018-02-05 接受日期:2018-04-26 出版日期:2018-05-20 发布日期:2018-09-11
  • 通讯作者: 张爱勤
  • 作者简介:# 共同第一作者
  • 基金资助:
    国家自然科学基金(31560183)

Temporal variation of plant sexes in a wild population of Tulipa sinkiangensis over seven years

Juan Wang, Yaxin Zhai, Aiqin Zhang*()   

  1. College of Life Science and Technology, Xinjiang University, Urumqi 830046
  • Received:2018-02-05 Accepted:2018-04-26 Online:2018-05-20 Published:2018-09-11
  • Contact: Zhang Aiqin
  • About author:# Co-first authors

摘要:

在雌雄同株植物中, 花性别被认为是两性资源分配对环境条件的响应, 了解个体性别随时间的变化对探讨植物性系统的变异有重要意义。早春短命植物新疆郁金香(Tulipa sinkiangensis)多为两性花居群, 前期调查显示一些居群由雄花和两性花构成。为了探讨新疆郁金香雄花的发生与变化, 我们连续7年对一个居群的花性别及其变化动态进行了跟踪。结果显示: (1)该居群主要是由一朵花植株和两朵花植株构成, 分别占居群植株总数的74.5%和23.0%。两种性别的花随机分布在不同类型的单株上, 形成了以两性花植株为主, 含有雄株、雄花与两性花同株(andromonoecy)的居群结构。(2)雄花相对较小, 子房退化, 无胚珠发育, 在植株或居群中花期较晚出现。与相同大小的两性花相比, 雄花在单花花粉量、花粉败育率、花粉粒大小及形态、雄性功能等方面没有差异。(3) 7年间, 雄花在居群中的比例经历了2011-2014年间的显著下降(23.4-3.1%)和2015-2017年间相对稳定的零星分布(1.5-1.0%)两个阶段。居群中一朵花植株数量和两朵花植株数量在年份间呈波动性变化。(4)雄花的出现可能是植株受自身资源状况及环境条件等因素的影响在花性别选择上作出的可塑性反应。

关键词: 新疆郁金香, 性别分化, 雄花, 性别比例, 动态变化

Abstract:

Understanding the variation in plant sexual strategies provides insights into the evolution of plant sexual systems. In hermaphrodite plants, floral gender is thought to be a plastic response that allows individuals to vary resource allocation to both female and male function under variable environmental conditions. Tulipa sinkiangensis is known to be hermaphroditic, early spring ephemeral plant, but our preliminary investigation showed that some populations had perfect flowers whereas other populations had staminate flowers. To understand correlates of occurrence and temporal variation of staminate flowers in T. sinkiangensis, we examined flower sex and its variation among individuals in a population of nearly 1,000 plants in Xinjiang, northwestern China from 2011 to 2017. (1) In the study population one-flower and two-flower plants comprised 74.5% (4,373) and 23.0% (1,358) of all flowering individuals (5,863), respectively. Sex differentiation was seen primarily in drier areas with shallow soils. Perfect and staminate flowers randomly occurred on different plants, constituting a hermaphroditic based population with some male and andromonoecious individuals. (2) Compared to perfect flowers, staminate flowers appeared later within individual plants and in the whole population during flowering. Staminate flowers were smaller and had aborted ovaries without visible ovules. However, pollen number and size, pollen morphology and fertility were not significantly different from perfect flowers when the two floral morphs were the same size. (3) During 2011 to 2014 of the study period, percentage of staminate flowers in the population declined from 23.4% to 3.1% but remained at stable (1.5% to 1.0%) from 2015 to 2017. The number of one-flower plants and two-flower plants fluctuated with time. (4) Our observations suggest that the production of staminate flowers in this endemic tulip flower was likely a plastic response to plant resource status, environmental conditions and other ecological factors.

Key words: Tulipa sinkiangensis, gender differentiation, staminate flowers, sex ratio, temporal variation