遮荫对香果树叶片生理特性及叶肉细胞超微结构的影响  

Effects of Shading on Physiological Characteristics and Ultrastructure of Mesophyll Cell of Emmenopterys henryi Leaves

作　　者：李冬林[1] 金雅琴[2] 崔梦凡 黄琳曦 裴文慧 LI Dong-Lin;JIN Ya-Qin;CUI Meng-Fan;HUANG Lin-Xi;PEI Wen-Hui(Forestry Academy of Jiangsu,Nanjing 211153;Department of Horticulture Jinling Institute of Technology,Nanjing 210038)

机构地区：[1]江苏省林业科学研究院,南京211153 [2]金陵科技学院园艺学院,南京210038

出　　处：《植物研究》2020年第1期29-40,共12页Bulletin of Botanical Research

基　　金：江苏省重点研发计划(现代农业)项目(BE2017387)~~

摘　　要：设置全光照(L0)、透光率60%(L1)、透光率25%(L2)、透光率10%(L3)4种光环境,通过遮荫试验研究不同光照条件对香果树幼苗生理特性及叶肉细胞超微结构的影响。结果表明:遮荫影响叶片含水量及叶片形态。随着遮荫强度的加大,叶片含水量(LWC)递增,单叶面积(SLA)增加,单叶干重(SLW d)和比叶重(LAM)减小,比叶面积(LAM)增大。遮荫条件下幼苗光合作用效率呈现显著变化。全光和L 1处理的P n和T r日变化呈明显的双峰曲线,出现了明显的“午休”,其余处理的变化相对缓和,双峰和“午休”现象不明显;G s的日变化与P n类似。P n和T r的日均大小排序为L1>L0>L2>L3。轻度遮光有利于香果树光合作用效率的提高。遮荫条件下叶片叶绿素和类胡萝卜素含量均有一定程度增加,且随着遮荫强度的加大其含量递增,提高了叶片的捕光能力。遮荫条件下MDA变化较为缓和,SOD、POD活性呈现先升后降的变化,但遮荫下的MDA含量始终小于全光照,可溶性糖也呈现类似的变化。全光下叶绿体与细胞壁平行分布,呈梭形,类囊体排列均匀,淀粉粒和嗜锇颗粒较少;遮荫条件下细胞内叶绿体数量有所增加,在整个细胞中占有比例显著增大,淀粉粒含量增多,类囊体排列紧密,堆叠程度增高,提高了弱光下的光合效率。适度遮荫香果树幼苗能维持正常的生理活动,但有效辐射光强须为自然光强的60%以上。We studied the effects of light on physiological characteristics and ultrastructure of mesophyll cells of Emmenopterys henryi leaves with four different light treatments:total light(L 0),transmittance 60%(L 1),transmittance 25%(L 2)and transmittance 10%(L 3).The results showed that:Shading affected the leaf water content(LWC)of and leaf morphology.With the increase of shading intensity,LWC increased,single leaf area(SLA)increased,single leaf dry weight(SLW d)and lamina mass per unit area(LMA)decreased,and lamina area per unit mass(LAM)increased.Shading had a significant effect on photosynthesis of seedlings.The diurnal changes of both P n and T r showed obvious bimodal curves for L 0 and L 1,and the“noon break”appeared at 12:00,and the change of both L 2 and L 3 was relatively mild,the phenomena werenot obvious.The variation of G s was basically consistent with that of P n.The order of daily average of both P n and T r was L 1>L 0>L 2>L 3.Therefore,the moderate shading is beneficial to the improvement of photosynthesis efficiency of E.henryi seedlings.Chlorophyll and carotenoid of leaves were increased under shading condition,and the contents of both chlorophyll and carotenoid were increased progressively with the increase of shading intensity.Long-term shading improved the light capture ability of leaves.Under shading condition,the change of MDA was more moderate,the activity of SOD and POD increased first and then decreased,but the MDA content under shading was always lower than that in full light.Soluble sugar showed a similar change.Under full light,the chloroplast and cell wall were distributed parallel to each other,and the thylakoid was evenly arranged,while under shading condition,the number of chloroplasts in cells increased obviously,the percentage of chloroplasts in the whole cell increased significantly,the starch granules increased,the arraying of thylakoids was close and the stacking degree increased,which improved the photosynthetic efficiency of the cells under low light.The seedlings can main

关 键 词：香果树 遮荫 生理特性 超微结构 

分 类 号：Q945.79[生物学—植物学]