• Flowers, the reproductive organs of angiosperms, show a high degree of diversity in morphological structure and flowering habit to ensure pollination and fertilization of the plants. Effect of flower movement on pollination and fertilization was investigated in Ipomoea purpurea (Convolvulaceae) in this study.
• Fluorescence microscopy was used to observe the germination of pollen grains at different temperatures.
• From 04:00 to 06:00 h, the stigma was taller than the filaments, so that self‐pollination could not occur, and cross‐pollination was carried out by insects. Pollen grains germinated rapidly after falling on the stigma; the pollen tube reached the ovule to complete fertilization after 2–3 h. From 07:00 to 09:00 h, filaments of two stamens grew rapidly and reached the same height as the stigma, thus allowing self‐crossing. But at this time, the ambient temperature was already high and was not conducive to the germination of pollen grains. The corolla closed, forming an inverted bell shape, where the inner microenvironment ensured completion of pollen germination and fertilization.
• Preferential cross‐pollination and delayed self‐crossing of I. purpurea provided a doubly guaranteed mechanism for pollination and fertilization, facilitating its adaptation to a high temperature climate.

中文翻译：

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紫菜的授粉和受精机制有双重保证。

• 花，被子植物的生殖器官，在形态结构和开花习性上表现出高度的多样性，以确保植物的授粉和受精。花运动对授粉受精的影响进行了研究牵牛花（旋在这项研究中）。
• 使用荧光显微镜观察在不同温度下花粉粒的萌发。
• 从04:00到06:00，柱头比花丝高，因此不会发生自花授粉，并且昆虫会进行异花授粉。花粉粒落在柱头上后迅速发芽。花粉管在2至3小时后到达胚珠以完成受精。从07:00到09:00 h，两个雄蕊的花丝迅速生长并达到与柱头相同的高度，从而实现自交。但是此时，环境温度已经很高，不利于花粉粒的萌发。花冠闭合，形成倒钟形，内部微环境确保花粉萌发和受精。
• 紫花苜蓿的优先异花授粉和迟交自交为授粉和施肥提供了双重保证的机制，有利于其适应高温气候。