不同光照强度对濒危植物丹霞梧桐的生长及光适应研究  

Effects of Different Light Intensities on the Growth and Light Adaptation of Endangered Species Firmiana danxiaensis

作　　者：陈灼康 莫罗坚 黄倩琳 陈葵仙 李炯祥 CHEN Zhuokang;MO Luojian;HUANG Qianlin;CHEN Kuixian;LI Jiongxiang(Dongguan Institute of Forestry Science/Forest Ecosystem Research Station in City Cluster of the Pearl River Estuary,Dongguan,Guangdong 523106,China;Dalingshan Forest Park Management Department,Dongguan,Guangdong 523959,China;Dongguan Forestry Affairs Center,Dongguan,Guangdong 523003,China)

机构地区：[1]东莞市林业科学研究所/广东珠江口城市群森林生态系统国家定位观测研究站,广东东莞523106 [2]东莞市大岭山森林公园,广东东莞523959 [3]东莞市林业事务中心,广东东莞523003

出　　处：《林业与环境科学》2023年第4期76-80,共5页Forestry and Environmental Science

基　　金：东莞市社会科技发展项目(2019507101550)。

摘　　要：为探讨濒危植物丹霞梧桐Firmiana danxiaensis对不同光照强度的适应机制,以半年生幼苗为对象,在不同光照强度(CK、L1、L2、L3,即遮荫度分别为0%、25%、50%和75%)下,比较其生长和光响应曲线。结果表明:随着遮荫强度的增大,丹霞梧桐苗高、地径的净生长量和总生物量呈先上升后下降趋势,比叶重呈下降趋势,但比叶面积呈上升趋。其生长量、生物量均以L1处理最高,苗高、地径净生长量和总生物量分别为28.94 cm、0.99 mm和25.16 g·株^(^(-1))。随着光合有效辐射的增大,其净光合速率增长幅度表现为CK>L1>L2>L3;在全光照条件下,丹霞梧桐具有较高的最大净光合速率(16.12 mmol·m^(^(-2))·s^(-1))、光饱和点(24.33μmol·m^(-2)·s^(-1))和暗呼吸速率(1.41μmol·m^(-2)·s^(-1))。PCA分析结果表明,不同光照强度对丹霞梧桐生长及光合参数呈显著相关性。在光照胁迫处理下,丹霞梧桐通过提高总生物量、增加比叶面积,降低根冠比和比叶重来提高其生长,以及适应特定的光环境,表明该物种的生长受光环境因子影响大。To explore the photosynthetic adaptation of the endangered species Firmiana danxiaensis to different light conditions,half-year-old seedlings were planted under different light environments(CK,L1,L2,L3,shade degrees were 0%,25%,50%and 75%,respectively),the growth and light response curves were compared.The results showed that with the increase of shading intensity,the net growth and total biomass of height and diameter increased first and then decreased,and the specific leaf weight decreased,but the specific leaf area increased.The height,diameter and total biomass were 28.94 cm,0.99 mm and 25.16 g per plant,respectively.With the increase of photosynthetic effective radiation,the growth range of net photosynthetic rate was arranged CK>L1>L2>L3.The higher maximum net photosynthetic rate(16.12 mmol·m^(-2)·s^(-1)),light saturation point(24.33μmol·m^(-2)·s^(-1))and dark respiration rate(1.41μmol·m^(-2)·s^(-1)).The results of PCA analysis showed that the growth and photosynthetic parameters were significantly correlated with different light intensities.Under light stress,it could adapt to the special light environment by increasing the total biomass,increasing the specific leaf area,decreasing the root-shoot ratio and the specific leaf weight.The results showed that the growth of this species was greatly influenced by light environment factors.

关 键 词：丹霞梧桐 光照强度 光适应 濒危植物 

分 类 号：S723.1[农业科学—林木遗传育种]