Wuyun Tana, Zhang Lu, Tosens Tiina, Liu Bin, Mark Kristiina, Morales-Sánchez José Ángel, Rikisahedew Jesamine Jöneva, Kuusk Vivian, Niinemets Ülo
Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1, Tartu 51014, Estonia.
College of Landscape and Architecture, Zhejiang A&F University, 666 Wusu Street, Hangzhou 311300, China.
Plant Divers. 2024 Apr 26;46(5):621-629. doi: 10.1016/j.pld.2024.04.009. eCollection 2024 Sep.
Leaf economics spectrum (LES) describes the fundamental trade-offs between leaf structural, chemical, and physiological investments. Generally, structurally robust thick leaves with high leaf dry mass per unit area (LMA) exhibit lower photosynthetic capacity per dry mass ( ). Paradoxically, "soft and thin-leaved" mosses and spikemosses have very low , but due to minute-size foliage elements, their LMA and its components, leaf thickness (LT) and density (LD), have not been systematically estimated. Here, we characterized LES and associated traits in cryptogams in unprecedented details, covering five evolutionarily different lineages. We found that mosses and spikemosses had the lowest LMA and LT values ever measured for terrestrial plants. Across a broad range of species from different lineages, and LD were negatively correlated. In contrast, was only related to LMA when LMA was greater than 14 g cm . In fact, low reflected high LD and cell wall thickness in the studied cryptogams. We conclude that evolutionarily old plant lineages attained poorly differentiated, ultrathin mesophyll by increasing LD. Across plant lineages, LD, not LMA, is the trait that represents the trade-off between leaf robustness and physiology in the LES.
叶经济谱（LES）描述了叶片结构、化学和生理投资之间的基本权衡。一般来说，具有高单位面积叶干质量（LMA）的结构坚固的厚叶，其单位干质量的光合能力较低（ ）。矛盾的是，“柔软薄叶”的苔藓和卷柏的光合能力非常低，但由于其叶片元素尺寸微小，它们的LMA及其组成部分，叶厚度（LT）和密度（LD）尚未得到系统估计。在这里，我们以前所未有的细节描述了隐花植物中的LES和相关性状，涵盖了五个进化上不同的谱系。我们发现，苔藓和卷柏的LMA和LT值是陆地植物中测量到的最低值。在来自不同谱系的广泛物种中，光合能力（ ）和LD呈负相关。相比之下，只有当LMA大于14 g/cm 时，光合能力（ ）才与LMA相关。事实上，在所研究的隐花植物中，低光合能力（ ）反映了高LD和细胞壁厚度。我们得出结论，进化古老的植物谱系通过增加LD实现了分化程度低的超薄叶肉。在整个植物谱系中，代表LES中叶坚固性和生理之间权衡的性状是LD，而不是LMA。
