生物多样性 ›› 2021, Vol. 29 ›› Issue (7): 887-896.DOI: 10.17520/biods.2020444

• 研究报告:植物多样性 • 上一篇    下一篇

青篱柴通过促进亲和花粉生长而提高传粉精确性

胡德美1,2,3, 姚仁秀1,2,3, 陈燕1,2,3, 游贤松3, 王顺雨3, 汤晓辛1,3, 王晓月1,3,*()   

  1. 1.贵州师范大学西南喀斯特山地生物多样性保护国家林业和草原局重点实验室, 贵阳 550025
    2.贵州师范大学贵州省植物生理与发育调控重点实验室, 贵阳 550025
    3.贵州师范大学生命科学学院, 贵阳 550025
  • 收稿日期:2020-11-29 接受日期:2021-02-04 出版日期:2021-07-20 发布日期:2021-03-23
  • 通讯作者: *王晓月 E-mail: wang.xiaoyue1989@163.com
  • 基金资助:
    国家自然科学基金(31901208);国家自然科学基金委员会贵州省人民政府喀斯特科学研究中心项目(U1812401);贵州省科学技术基金(2019/1237);贵州师范大学博士科研启动项目(2017/22)

Tirpitzia sinensis improves pollination accuracy by promoting the compatible pollen growth

Demei Hu1,2,3, Renxiu Yao1,2,3, Yan Chen1,2,3, Xiansong You3, Shunyu Wang3, Xiaoxin Tang1,3, Xiaoyue Wang1,3,*()   

  1. 1 Key Laboratory of Southwest Karst Mountain Biodiversity Conservation of National Forestry and Grassland Administration, Guizhou Normal University, Guiyang 550025
    2 Key Laboratory of Plant Physiology and Development of Guizhou Province, Guizhou Normal University, Guiyang 550025
    3 College of Life Sciences, Guizhou Normal University, Guiyang 550025
  • Received:2020-11-29 Accepted:2021-02-04 Online:2021-07-20 Published:2021-03-23
  • Contact: *Xiaoyue Wang E-mail: wang.xiaoyue1989@163.com

摘要:

异型花柱植物的适应意义在于提高亲和花粉的传递, 从而促进异交, 但是有不少研究发现柱头上落置了大量不亲和花粉。目前, 很少有人研究柱头是否有利于亲和花粉的萌发和花粉管伸长, 以及通过去雄处理排除花内和植株内不亲和花粉干扰从而验证二型花柱植物是否可以促进异交。本研究以亚麻科青篱柴属(Tirpitzia)的二型花柱植物青篱柴(T. sinensis)为研究对象, 分居群调查了青篱柴长、短柱型的植株数量, 测量不同柱型的花粉与柱头大小以及观察其表面纹饰, 测定不同开花时间长、短柱型的柱头活性与花粉活力, 统计自然状态下柱头上落置的不同表型花粉比例, 进一步统计花内、株内去雄和自然对照下柱头上落置的不同表型花粉比例, 计算型间、型内和混合授粉花粉管长度和花粉萌发率, 人工授粉检测其是否型内异交不亲和与自交不亲和。结果表明, 自然居群中长、短柱型青篱柴植株数量没有显著性差异; 短柱型青篱柴花粉体积显著大于长柱型, 且二者花粉表面纹饰不同, 但不同柱型的柱头表面积与表面纹饰无差异; 青篱柴开花第一天的花粉活力显著高于开花第二天, 而柱头活性在开花前两天无显著性差异; 自然状态下柱头上落置的不亲和花粉比例显著高于亲和花粉; 在长柱型青篱柴中, 花内和株内去雄显著提高了柱头上亲和花粉的落置比例; 柱头上授型内花粉, 其花粉萌发率和花粉管的长度都显著低于授型间花粉; 授粉结果表明青篱柴为型内异交不亲和与自交不亲和。二型花柱植物通过促进亲和花粉的萌发和花粉管的伸长而有利于型间授粉, 从而显著提高其传粉精确性。

关键词: 异型花柱植物, 青篱柴, 传粉精确性, 萌发率, 花粉管长度

Abstract

Aims: The adaptive significance of heterostyly is to improve the transfer of compatible pollen, so as to promote outcrossing. Nevertheless, many studies have found that a large number of incompatible pollens are deposited on the stigmas. At present, few studies have focused on whether the stigmas promote the compatible pollen germination and pollen tube elongation and provide evidences for the pollination accuracy hypothesis by emasculating intraflower and intraplant pollen.
Methods: Tirpitzia sinensis (Linaceae) was taken as materials, and the number of long-styled morph (L-morph) and short-styled morph (S-morph) of T. sinensis were investigated in the separate populations. The pollens and stigmas size of different morphs were measured and their surface ornamentations were observed. The viability of stigma and pollen of different flowering phases were measured. The percentage of different phenotypic pollens on the stigma were calculated. The percentage of compatible and incompatible pollens on the stigma were further calculated under intraflower, intraplant emasculation and natural control treatments. The pollen tube length and pollen germination rate of inter-morph, intra-morph and mixture pollination were measured. The heteromorphic self-incompatibility system was detected by artificial pollination treatments.
Results: There was no significant difference in the number of L-morph and S-morph of T. sinensis in the natural populations. The pollen volume of S-morph was significantly larger than that of L-morph, and the pollen surface ornamentations of the two morphs were different, but there were no significant different in the stigma surface areas and surface ornamentations of the two morphs. The pollen viability of the first flowering day was significantly higher than that of the second day, while the stigma viability had no significant difference in the first and second day of flowering. The percentage of incompatible pollen on stigma was significantly higher than that of compatible pollen in natural state. The intraflower and intraplant emasculation treatments significantly increased the percentage of compatible pollen deposition compared with the natural control in the L-morph of T. sinensis. Compared with inter-morph pollination treatment, the intra-morph pollination treatment could significantly reduce pollen germination rate and pollen tube length. Pollination treatments showed that T. sinensis was self- and intramorphic pollination incompatible.
Conclusions: These results indicate that the distyly improves pollination accuracy by promoting the compatible pollen germination and pollen tube elongation.

Key words: heterostylous plants, Tirpitzia sinensis, pollination accuracy, germination rate, pollen tube length