More than two-thirds of the species in exhibit remarkable reproductive phenology, characterized by prolonged fruit ripening and the occurrence of overlapping fruit ripening and flowering. However, the underlying reasons for these phenomena remain unknown. Therefore, this study employed routine paraffin section technology, histochemical technique and scanning electron microscopy to investigate embryo sac development, differences between male and hermaphroditic flowers, as well as the overwintering strategy in . The findings of this study revealed a significant reduction in pollen viability and the number of pollen grains per flower in hermaphroditic compared to male flowers. Following fertilization, the ovary of hermaphroditic flowers does not undergo significant enlargement but gradually enters the state of zygotic quiescence. Zygotic quiescence prolongation is the main reason for the long reproductive cycle of , and it takes approximately 14 months for the entire cycle from flower bud differentiation to fruit ripening to complete. Long reproductive cycle and complex overwintering mechanism exhibited by resemble those seen in species belonging to Betulaceae, Fagaceae, Tapisciaceae, and Theaceae, suggesting convergent evolution during Earth's glacial period resulted in similar adaptive structures among these groups delayed fruit ripening leads to overlap between current year's flowers with previous year's fruits. The trade-off between flower and fruit for reproductive resources may have driven evolutionary transition from ancestral hermaphroditism towards androdioecy in .

中文翻译：

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合子静止延长了 Berchemia sinica（鼠李科）的繁殖周期

超过三分之二的物种表现出显着的繁殖物候，其特点是果实成熟时间延长以及果实成熟和开花重叠。然而，这些现象的根本原因仍然未知。因此，本研究采用常规石蜡切片技术、组织化学技术和扫描电镜技术来研究花的胚囊发育、雄花和雌雄花的差异以及越冬策略。这项研究的结果表明，与雄花相比，雌雄同体的花粉活力和每朵花的花粉粒数量显着降低。受精后，两性花的子房并不明显增大，而是逐渐进入合子静止状态。合子静止期延长是其繁殖周期长的主要原因，从花芽分化到果实成熟完成整个周期大约需要14个月。长繁殖周期和复杂的越冬机制与桦木科、壳斗科、瘿花科和山茶科的物种相似，表明地球冰期期间的趋同进化导致这些群体之间具有相似的适应性结构，延迟果实成熟导致当年花朵之间的重叠加上去年的水果。花和果实之间对生殖资源的权衡可能推动了从祖先的雌雄同体向雌雄同体的进化转变。