Humphreys Emily A, Skema Cynthia
Morris Arboretum & Gardens of the University of Pennsylvania Philadelphia Pennsylvania USA.
Ecol Evol. 2023 Jul 3;13(7):e10219. doi: 10.1002/ece3.10219. eCollection 2023 Jul.
Anther opening has commonly been thought of as unidirectional, but reports of anthers closing in response to rainfall show this is not the case. In some species, anther closure can protect pollen from degrading or washing away, thus possibly enhancing male fitness. Similarly, although floral color is often presumed to be static, numerous floral parts may change color during blooming. These color changes primarily occur in response to pollination or aging, thus potentially increasing pollination efficiency by directing floral visitors to recently opened, unpollinated flowers. Daily observations of 364 flowers from seven individuals showed that anthers that were purple, open, and shedding pollen became beige colored and tightly closed after rainfall. These findings were further supported by observations of plants exposed to simulated rainfall in a greenhouse and time-lapse photography of flowers misted with water. To our knowledge, our work represents the first report of anther closure in response to rain in Malvaceae and the first report of floral color change induced by rainfall.
花药开裂通常被认为是单向的，但有关花药因降雨而闭合的报道表明并非如此。在一些物种中，花药闭合可以保护花粉不被降解或冲走，从而可能提高雄性适合度。同样，尽管花的颜色通常被认为是固定不变的，但许多花部在开花过程中可能会变色。这些颜色变化主要是对授粉或衰老的反应，从而有可能通过引导访花者前往最近开放的、未授粉的花朵来提高授粉效率。对来自7个个体的364朵花的日常观察表明，紫色、开放且正在散粉的花药在降雨后变成米色并紧闭。在温室中对暴露于模拟降雨的植物进行的观察以及对喷水花朵的延时摄影进一步支持了这些发现。据我们所知，我们的研究首次报道了锦葵科植物花药因降雨而闭合，以及降雨引起花颜色变化的情况。
