植物叶片机械强度与抗旱性耦合机制研究进展  

Research progress in the coordination between leaf mechanical structure and drought tolerance

作　　者：谢路路 张秀龙 于大炮[1,2] 王庆伟 XIE Lulu;ZHANG Xiulong;YU Dapao;WANG Qingwei(Key Laboratory of Forest Ecology and Silviculture,Institute of Applied Ecology,Chinese Academy of Sciences,Shenyang 110044,China;Changbaishan Xipo National Field Observation and Research Station for Forest Ecosystem,Baishan 134506,China;Chengdu Institute of Biology,Chinese Academy of Sciences,Chengdu 610213,China)

机构地区：[1]中国科学院沈阳应用生态研究所中国科学院森林生态与保育重点实验室,沈阳110044 [2]长白山西坡森林生态系统国家定位观测站,白山134506 [3]中国科学院成都生物研究所,成都610213

出　　处：《生态学报》2025年第4期1539-1548,共10页Acta Ecologica Sinica

基　　金：国家自然科学基金“优青”项目(32122059);中国科学院率先行动“百人计划”;国家资助博士后研究人员计划(GZC20232881);博士后面上基金(2024M753411)。

摘　　要：植物叶片机械强度(刚度和韧性)与其抗旱性之间存在一定的协同关系,是植物适应环境的重要策略。开展植物叶片机械强度与抗旱性耦合机制研究有助于理解和预测陆地植被对气候变化的响应和适应策略。由于缺少针对该协同关系驱动因素的系统性研究,当前对植物适应干旱的生理生态机制缺乏深入理解。从叶片机械结构、抗旱性状及驱动二者变化的相关解剖学/生理性状进行分析,在综述叶片机械结构与抗旱性状的基础上,阐明抗旱性与机械性状协同关系的解剖学和生理基础,以期为今后研究植物机械性状和抗旱协同适应策略提供参考。细胞壁厚度、膨压损失点(Ψ_(tlp))和主脉长度(VLA_(maj))在调节叶片机械强度和抗旱性的权衡关系中发挥重要作用:①较厚的细胞壁不仅能够降低细胞膨压损失后的皱缩和塌陷风险,也会保护叶片免受由细胞收缩引起的导管外水分运输能力下降,从而使得植物叶片有较强的耐旱能力;②叶脉维管束水分的运输在干旱下存在着由栓塞引发的被破坏风险,而单位面积较大的主脉长度(VLA_(maj))可以提供额外的水分替代途径向叶肉供应水分;③较厚的细胞壁厚度和较高的VLA_(maj)有助于增加叶片的机械强度。综上所述,在干旱生境中,尽管水分亏缺会降低叶片光合速率,但具有高机械强度和抗旱性的叶片却能延长其寿命,以保证叶片在恶劣生境中维持基本的气体交换和正碳收益。揭示了高机械性和抗旱性的耦合是植物适应干旱的内在机制,并对植物抗旱性的研究进行展望,强调未来研究在考虑植物机械性状的基础上,需要结合植物功能性状和生理因素如渗透调节能力、水分缓冲能力等协同探究植物的抗旱性,以期为未来植物抗旱协同策略提供指导。There is a synergistic relationship between the mechanical strength(stiffness and toughness)of plant leaves and their drought resistance,which is an important strategy for plants to adapt to environment.Research on the interplay between the mechanical strength and drought resistance of plant leaves aids in understanding and predicting the responses and adaptive strategies of terrestrial plants to climate change.However,due to the lack of systematic research on the driving factors of this synergistic relationship,there is a lack of in-depth understanding of the physiological and ecological mechanisms of plant adaptation to drought.In this paper,leaf mechanical structure,drought resistance and related anatomical or physiological traits driving the relationship were analyzed,leaf mechanical structure and drought resistance were summarized,to clarify the anatomical basis of the synergistic relationship between drought resistance and anatomical or physiological traits,so as to provide reference for the future study of plant mechanical traits and drought resistance strategies.Among them,cell wall thickness,expansion pressure loss point(Ψ_(tlp))and main vein length(VLA_(maj))play important roles in regulating the balance between leaf mechanical strength and drought tolerance,1)a thicker cell wall not only reduces the risk of shrinkage and collapse after loss of cell bulging,but also protects the leaf from the reduction of extraductal water transport capacity caused by cell shrinkage,therefore,the plant leaves have strong drought resistance;2)the transport of water in vascular bundle of leaf vein has the risk of being destroyed by embolism under drought,and the larger length of main vein per unit area(VLA_(maj))can provide an additional way to supply water to mesophyll;3)thicker cell wall and higher VLA_(maj)help to increase the mechanical strength of leaves.In summary,although water deficit in arid habitats reduce the leaf photosynthetic rate,leaves with high mechanical strength and drought tolerance extend their lifes

关 键 词：比叶重 叶密度 细胞壁 粗脉密度 失膨点 叶水力导度 

分 类 号：Q948[生物学—植物学]