资源分配理论认为,生物体将有限的资源分配给各个功能,以最大程度地提高其整体适应性。在植物中,维护资源之间的分配,繁殖,增长影响短期经济和长期进化过程,尤其是在资源稀缺的时候。在繁殖和生长之间分配劳动的专门结构的进化可以创建一个反馈回路,在这个回路中,选择可以作用于单个器官,进一步增加专业化和资源分配。蕨类植物表现出不同的繁殖策略,包括二态,其中叶子可以是无菌的(仅用于光合作用)或可育的(用于孢子扩散)。这种二态现象类似于种子植物中的过程(例如,生产肥沃的花朵和无菌的叶子),并为研究特殊器官中生殖功能和营养功能之间的不同资源分配提供了机会。这里,我们对OnocleasensilisL.进行了解剖和水力分析,一种广泛分布的二态蕨类植物,揭示肥沃和不育叶片之间的显著结构和水力差异。肥沃的叶子在水力建筑上的投资较少,与无菌叶相比,导水细胞减少近1.5倍,抗旱木质部减少近0.5倍。这是因为结构性支持的相对投资增加了,这可能有助于促进孢子扩散。这些发现表明,蕨类植物的专业化-以生殖二态的形式-可以对每种叶片类型产生独立的选择压力,可能优化可育叶中的孢子扩散和不育叶中的光合效率。总的来说,我们的研究揭示了功能专业化的进化意义,并强调了生殖策略在塑造植物适应性和进化中的重要性。
Resource allocation theory posits that organisms distribute limited resources across functions to maximize their overall fitness. In plants, the allocation of resources among maintenance,
reproduction, and growth influences short-term economics and long-term evolutionary processes, especially during resource scarcity. The evolution of specialized structures to divide labor between
reproduction and growth can create a feedback loop where selection can act on individual organs, further increasing specializaton and resource allocation. Ferns exhibit diverse reproductive strategies, including dimorphism, where leaves can either be sterile (only for photosynthesis) or fertile (for spore dispersal). This dimorphism is similar to processes in seed plants (e.g., the production of fertile flowers and sterile leaves), and presents an opportunity to investigate divergent resource allocation between reproductive and vegetative functions in specialized organs. Here, we conducted anatomical and hydraulic analyses on Onoclea sensibilis L., a widespread dimorphic fern species, to reveal significant structural and hydraulic divergences between fertile and sterile leaves. Fertile fronds invest less in hydraulic architecture, with nearly 1.5 times fewer water-conducting cells and a nearly 0.5 times less drought-resistant xylem compared to sterile fronds. This comes at the increased relative investment in structural support, which may help facilitate spore dispersal. These findings suggest that specialization in ferns-in the form of reproductive dimorphism-can enable independent selection pressures on each leaf type, potentially optimizing spore dispersal in fertile fronds and photosynthetic efficiency in sterile fronds. Overall, our study sheds light on the evolutionary implications of functional specialization and highlights the importance of reproductive strategies in shaping plant fitness and evolution.