遮光处理对草珊瑚光合特性及叶片解剖结构的影响  

Effects of Shading Treatment on Photosynthetic Characteristics and Leaf Anatomical Structure of Sarcandra glabra

作　　者：聂小英 朱春晓 郑东升 陈阳峰[1] 李自强[1] 肖深根[1] NIE Xiaoying;ZHU Chunxiao;ZHENG Dongsheng;CHEN Yangfeng;LI Ziqiang;XIAO Shen'gen(College of Horticulture, Hunan Agricultural University, Changsha 410128, China;2Hunan Hinye Modern Chinese Medicine Industry Co.Ltd, Hengyang, Hunan 421256, China)

机构地区：[1]湖南农业大学园艺学院,长沙410128 [2]湖南天地恒一现代中药产业有限公司,湖南衡阳421256

出　　处：《西北植物学报》2021年第6期995-1002,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：中央引导地方科技发展专项资金科技创新项目(第二批)(2019FX5066);湖南省中药材产业技术体系项目(湘财农指[2020]64号,湘财农指[2020]112号)。

摘　　要：为探索遮光处理对草珊瑚光合特性及叶片解剖结构的影响,为草珊瑚的科学栽培提供理论依据。该研究以2年生草珊瑚为材料,设置全光照(L_(0))及50%(L_(50))、70%(L_(70))和90%(L90)遮光处理,测定分析其光合特性和叶片解剖结构以及植株生长的变化。结果表明:(1)随着遮光率的增加,草珊瑚叶面光合有效辐射(PAR)、气孔导度(Gs)和蒸腾速率(Tr)逐渐减小,胞间二氧化碳浓度(Ci)先减少后增加,净光合速率(Pn)先增加后减少,并在L_(50)和L_(70)处理下具有较低的PAR、Gs、Tr和Ci,光合‘午休’现象得到有效缓解,表现出更高的Pn。(2)随着遮光率的增加,草珊瑚光补偿点(LCP)逐渐下降,光饱和点(LSP)、暗呼吸速率(Rd)先升高后下降,表观量子效率(AQE)逐渐上升,叶片最大净光合速率(Pnmax)先升高后下降,并在L_(50)和L_(70)处理下具有较低的LCP,较高的LSP和AQE,以及更高的最大净光合速率。(3)随着遮光率的增加,草珊瑚叶片、表皮细胞、栅栏组织和海绵组织的厚度明显增加,角质层厚度逐渐变薄;在L_(50)和L_(70)处理下,草珊瑚叶片栅栏组织和海绵组织发达,栅栏组织细胞长度变短,海绵组织厚度显著增加,细胞排列疏松,叶绿体数量显著增加;叶肉细胞和叶绿体结构完整,基粒类囊体和基质类囊体片层结构发达,叶片捕获光能力增强。(4)随着遮光率的增加,草珊瑚株高、地径、总叶面积数及单株生物量先增加后减少,并在L_(70)处理下均达到峰值,分别为58.58 cm、5.09 mm、1038.53 cm^(2)和15.50 g。研究认为,草珊瑚具有一定的弱光耐受力和光可塑性,50%~70%遮光处理有利于草珊瑚生长,在实际生产中可根据该光照范围选择合适的间套作林分或进行适当的遮光处理。In order to explore the effects of shading treatment on photosynthetic characteristics and leaf anatomical structure of Sarcandra glabra,and provide theoretical basis for scientific cultivation of S.glabra,we treated 2-year-old S.glabra with four different shading treatments[L_(0)(0%),L_(50)(50%),L_(70)(70%),L90(90%)]to observe its photosynthesis,leaf anatomical structure and plant growth.The results showed that:(1)with the increase of shading rate,photosynthetic effective radiation(PAR),stomatal conductance(Gs)and transpiration rate(Tr)decreased gradually,intercellular carbon dioxide concentration(Ci)decreased first and then increased,and net photosynthetic rate(Pn)increased first and then decreased;Under L_(50) and L_(70) treatments,PAR,Gs,Tr and Ci were lower,photosynthetic‘midday depression’was effectively alleviated,and Pn was higher.(2)With the increase of shading rate,the light compensation point(LCP)decreased gradually,the light saturation point(LSP)and dark respiration(Rd)increased first and then decreased,the apparent quantum efficiency(AQE)increased gradually,and the maximum net photosynthetic rate(Pnmax)of leaves increased first and then decreased;Under L_(50) and L_(70) treatments,LCP was lower,LSP and AQE were higher,and Pnmax was higher.(3)With the increase of shading rate,the thickness of leaves,epidermal cells,palisade tissue and spongy tissue increased significantly,while the thickness of cuticle became thinner;Under L_(50) and L_(70) treatments,palisade tissue and spongy tissue were developed,palisade tissue cell length became shorter,spongy tissue thickness increased significantly,cell arrangement was loose,and chloroplast number increased significantly;Mesophyll cell and chloroplast structure were complete,granal thylakoid and stromal thylakoid lamellar structure were developed,and the ability of leaf to capture light was enhanced.(4)With the increase of shading rate,the plant height,ground diameter,total leaf area and biomass of S.glabra increased first and then decreased.Under L_(70) tr

关 键 词：草珊瑚 遮光处理 光合特性 叶片解剖结构 生长 

分 类 号：Q945.79[生物学—植物学] Q944.56