Zhao Xiang, Yang Guang, Hou Qinzheng, Min Wenrui, Wang Taihong, Bao Xiaoyan
College of Life Sciences Northwest Normal University Lanzhou China.
Ecol Evol. 2023 Feb 15;13(2):e9836. doi: 10.1002/ece3.9836. eCollection 2023 Feb.
Continuous variation in herkogamy has been well reported, however, less attention has been paid to the phenomena that the consecutive expression of two types of herkogamy in the same flower. which have both vertical and lateral herkogamy, show vertical herkogamy during the female phase However, their gynophores bend to one side with the male phase and show lateral herkogamy In this study, we observed the effect of successive sexual organs movement on variation in herkogamy traits. By artificially manipulating the flower to present gynophore straightened in the floral center or bend to one side, we attempted to investigate whether herkogamy movement affects pollinator access efficiency, pollen removal and deposition, and seed set ratio. Furthermore, we conducted artificial pollination in the female phase to evaluate the effect of changes in pollination environment on the variations in herkogamy traits. The results showed that gynophore straightened in female phase favors pollen deposition, whereas gynophore bending in male phase was conducive to the removal of pollen. Visitation frequency, pollen deposition and removal, and seed set ratio decreased significantly when the gynophore movement was manipulated. Finally, the bending of gynophore was obviously promoted by pollination. Therefore, the continuous variation of herkogamy in the same flower of caused by the bending of the gynophore could improve the accuracy of pollination and avoid the interference of the ovary with access efficiency. That may be an adaptive strategy when pollinators are scarce. Furthermore, our study also provides good support for the hypothesis that variations in herkogamy traits are strongly selected by differences in pollination environments.
尽管关于雌雄异位的连续变化已有充分报道，但同一朵花中两种类型的雌雄异位连续表达的现象却较少受到关注。具有垂直和侧向雌雄异位的花朵，在雌蕊期表现为垂直雌雄异位。然而，它们的雌蕊柄在雄蕊期向一侧弯曲，表现为侧向雌雄异位。在本研究中，我们观察了连续的性器官运动对雌雄异位特征变化的影响。通过人工操作花朵，使雌蕊柄在花中心伸直或向一侧弯曲，我们试图研究雌雄异位运动是否会影响传粉者的访问效率、花粉去除和沉积以及结实率。此外，我们在雌蕊期进行人工授粉，以评估授粉环境变化对雌雄异位特征变化的影响。结果表明，雌蕊柄在雌蕊期伸直有利于花粉沉积，而在雄蕊期弯曲则有利于花粉去除。当雌蕊柄运动受到控制时，访花频率、花粉沉积和去除以及结实率均显著降低。最后，授粉明显促进了雌蕊柄的弯曲。因此，雌蕊柄弯曲导致同一朵花中雌雄异位的连续变化可以提高授粉的准确性，避免子房对访问效率的干扰。这可能是传粉者稀缺时的一种适应性策略。此外，我们的研究也为雌雄异位特征的变化受到授粉环境差异强烈选择这一假设提供了有力支持。
