遮阴对南京椴容器苗叶片性状和光合生理的影响  

Effect of shading on leaf traits and photosynthetic characteristics of Tilia miqueliana container seedlings

作　　者：张禹琪 沈永宝[1] ZHANG Yuqi;SHEN Yongbao(College of Forestry and Grassland,College of Soil and Water Conservation,Nanjing Forestry University,Nanjing 210037,Jiangsu,China)

机构地区：[1]南京林业大学林草学院、水土保持学院,江苏南京210037

出　　处：《中南林业科技大学学报》2025年第1期58-69,共12页Journal of Central South University of Forestry & Technology

基　　金：江苏省农业科技自主创新资金项目(CX(23)3142);江苏高校优势学科建设工程资助项目(PAPD)。

摘　　要：【目的】探究不同光照环境对南京椴容器苗叶片性状和光合生理的影响。【方法】以1年生南京椴容器苗为试验材料,研究全光照(CK)、遮阴30%(T1)和遮阴50%(T2)对南京椴容器苗叶片性状、叶解剖结构、气体交换参数、光响应曲线、叶绿素荧光指标和光合色素的影响。【结果】随着遮阴强度的增大,南京椴容器苗的叶长、叶宽、单叶面积、叶含水率和叶鲜质量均显著增加,且在T2处理下达到最大值,而比叶质量则随着遮阴强度的增加而显著降低,在T2处理达到最小值。随着遮阴强度的增大,南京椴幼苗的叶解剖结构也发生了变化,上下表皮厚度、叶片厚度、表皮毛密度、栅栏组织厚度、海绵组织厚度、气孔密度、气孔指数以及栅海比均呈显著降低趋势,叶片疏松度则呈上升趋势。在光合作用方面,随着遮阴强度的增加,气孔导度、蒸腾速率和水分利用效率逐渐上升,净光合速率先升后降,胞间二氧化碳浓度则先降后升。同时,暗呼吸速率和光补偿点逐渐降低,而最大净光合速率显著增加。在叶绿素荧光参数方面,最大荧光、可变荧光、PSⅡ最大光化学效率、PSⅡ潜在光化学效率和PSⅡ有效光化学量子效率均随遮阴强度的增加而升高,初始荧光在CK处理下为最大值,呈现先下降后上升的趋势,光化学淬灭系数、非光化学淬灭系数和表观光合量子传递效率呈现先升高后下降的趋势,在遮阴30%时达到最大值。随着遮阴强度的增大,光合色素含量均呈显著上升趋势,但叶绿素a/b、类胡萝卜素/叶绿素的比值却显著下降。【结论】南京椴容器苗对弱光环境适应能力较强。在8月中旬,遮阴50%对1年生南京椴容器苗生长较为有利。【Objective】This article aims to investigate the effects of different light conditions on leaf traits and photosynthetic physiology of Tilia miqueliana container seedlings.【Method】Taking 1-year-old Tilia miqueliana container seedlings as test materials,this study focuses on the leaf traits,leaf anatomical structure,gas exchange parameters,light response curves,chlorophyll fluorescence indices and photosynthetic pigments of Tilia miqueliana container seedlings under three light conditions,which are full sunlight(CK),30%shading(T1),and 50%shading(T2).【Result】With the increase of shading intensity,Tilia miqueliana container seedlings showed significant changes in a number of indicators.Leaf length,leaf width,leaf area,leaf water content and leaf fresh weight increased significantly,and reached the maximum under T2 treatment.On the contrary,specific leaf mass decreased significantly with the increase of shading degree,minimum at T2 treatment.In addition,the leaf anatomical structure of Tilia miqueliana seedlings changed with the increase of shading intensity,the thickness of upper and lower epidermis,leaf thickness,epidermal hair density,palisade tissue thickness,spongy tissue thickness,stomatal density,stomatal index and barrier-to-sea ratio all showed a significant decreasing trend,the porosity of the leaves showed an upward trend.In photosynthesis,stomatal conductance,transpiration rate and water use efficiency increased,net photosynthetic rate increased first and then decreased,and intercellular carbon dioxide concentration decreased first and then increased with the increase of shading degree.At the same time,the dark respiration rate and light compensation point decreased gradually,while the maximum net photosynthetic rate increased significantly.The maximum fluorescence,variable fluorescence,maximum photochemical efficiency of PSII,potential photochemical efficiency of PSII and effective photochemical quantum efficiency of PSII all increased with the increase of shading degree,the initial fluorescen

关 键 词：南京椴 遮阴 叶解剖结构 光合特性 叶绿素荧光 

分 类 号：S718.43[农业科学—林学] S723.133