遮光对糠椴幼苗光合特性的研究  

Effects of shading on photosynthetic physiology of Tilia mandshurica Seedlings

作　　者：刘兴 赵丹[1] 杨晓 金梦然 刘煜光[1] 史宝胜[1] LIU Xing;ZHAO Dan;YANG Xiao;JIN Mengran;LIU Yuguang;SHI Baosheng(College of Landscape and Tourism, Hebei Agricultural University,Baoding 071000,China)

机构地区：[1]河北农业大学园林与旅游学院,河北保定071000

出　　处：《林业与生态科学》2020年第1期86-92,共7页Forestry and Ecological Sciences

基　　金：河北省科技厅项目(17226320D-5)。

摘　　要：为阐明糠椴(Tilia mandshurica Rup et Maxim.)对不同光环境的光合特性,以2 a生糠椴实生苗为试验材料,设定4个遮光度,分别为透光率100%(CK)、透光率70%(轻度遮光,LS)、透光率40%(中度遮光,MS)、透光率10%(重度遮光,SS)。研究处理后叶片净光合速率日变化、光响应参数、叶绿素含量等的变化。结果表明:(1)随着遮光度的增加,幼苗净光合速率、气孔导度、蒸腾速率和水分利用率先升高后降低,胞间CO2浓度先降低后升高;(2)轻度遮光处理下,幼苗光响应参数表观量子效率(AQY)、光补偿点(LCP)、最大净光合速率(Pmax)显著提升,光饱和点(LSP)和暗呼吸速率(Rd)降低;(3)轻度遮光处理下的最大光化学效率(Fv/Fm)、能量分配比例参数中吸收的光能被反应中心捕获的量子产量(φPo)、激子被反应中心捕获后促进电子传递到电子传递链中超过QA的电子受体的激子与促进QA还原激子的比值(Ψo)、单位反应中心所捕获的应用到电子传递的能量(ETo/RC)的值显著增加。(4)糠椴叶绿素b和叶绿素总量随遮光度的升高而增加。叶绿素a/b随遮光度的增加而降低。综合各指标分析认为:轻度遮光环境有利于提升糠椴幼苗的光合特性,促进幼苗生长。In order to clarify the photosynthesis characteristics of Tilia mandshurica Rup et Maxim.in different light environments,the two-year-old Tilia mandshurica seedlings were used as test materials,and four shading degrees were set,which were 100%transmittance(CK),70%transmittance(light shading),40%transmittance(moderate shading),and 10%transmittance(severe shading).The changes of daily net photosynthetic rate,light response parameters and chlorophyll content of the leaves were studied.The results showed that:(1)With the increase of opacity,Pn,Gs,Tr and WUE of seedlings increased first and then decreased,Ci decreased first and then increased.(2)Under light shading,the light response parameters of seedlings AQY,LCP,and Pmax were significantly improved,while LSP and Rd were decreased.(3)The values of Fv/Fm,φPo,Ψo,and ETo/RC under light shading condition increased significantly.(4)The total amount of chlorophyll b and chlorophyll increased with the increase of opacity.Chlorophyll a/b decreased with increasing opacity.According to the analysis of various indicators,the light shading environment is conducive to improving the photosynthetic characteristics of Tilia mandshurica seedlings and promoting seedling growth.

关 键 词：糠椴 遮光环境 光合特征 叶绿素含量 

分 类 号：S792.36[农业科学—林木遗传育种]