文献类型：期刊文献

中文题名：遮荫对濒危植物崖柏光合作用和叶绿素荧光参数的影响

英文题名：Effects of shading on photosynthetic characteristics and chlorophyll fluorescence parameters in leaves of the endangered plant Thuja sutchuenensis

作者：刘建锋[1,2] 杨文娟[1] 江泽平[1] 郭泉水[3] 金江群[3] 薛亮[1]

第一作者：刘建锋

机构：[1]中国林业科学研究院林业研究所;[2]国家林业局林木培育重点实验室;[3]中国林业科学研究院森林生态环境与保护研究所

年份：2011

卷号：31

期号：20

起止页码：5999-6004

中文期刊名：生态学报

外文期刊名：Acta Ecologica Sinica

收录：CSTPCD;;Scopus;北大核心:【北大核心2008】；CSCD:【CSCD2011_2012】；

基金：中央级公益性科研院所基本科研业务费专项资金(RIF2010-15);国家林业局野生植物保护管理项目(1691000401)

语种：中文

中文关键词：崖柏;遮荫;光合作用;叶绿素荧光;光适应

外文关键词：Thuja sutchuenensis; shade; photosynthetic; chlorophyll fluorescence; acclimation to light

分类号：Q945.11

摘要：崖柏(Thuja sutchuenensis)是我国特有的极度濒危植物。目前尚缺乏从光合生理角度对其濒危机制开展讨论与研究。光是影响植物生存和生长发育最重要的环境因子之一,且有可能成为植物种群自然更新的主要限制因子。因此,通过人工遮荫方式,探讨了3种光环境下(L0全光,L1-50%全光,L2-25%全光)崖柏幼苗的光合能力及叶绿素荧光参数的差异。结果表明,遮荫导致了叶片表观量子效率和最大净光合速率增加。随着生长光强的降低,崖柏幼苗的暗呼吸速率、光补偿点和光饱和点均有所下降。叶绿素荧光参数方面,遮荫导致了PSⅡ原初光能转换效率(Fv/Fm)、PSⅡ潜在活性(Fv/Fo)、PSⅡ有效光量子产量(Fv'/Fm')和非光化学猝灭系数(NPQ)增加;但随着生长光强减弱,崖柏幼苗叶片的光化学猝灭系数(PQ)和电子传递速率(ETR)逐渐降低。同时,遮荫也造成了叶片叶绿素含量(Chla+Chlb)的显著增加。结果表明,崖柏对光具有较强的耐受范围(尤其是低光)和内在调节机制,初步判定崖柏林下光照的不足不会成为崖柏自然更新的决定性限制因子。
Thuja sutchuenensis Franch.is a critically endangered plant that is endemic to China.Currently,no research has addressed its endangered status from the perspective of its photosynthetic mechanism.Light is one of the most important environmental factors that can affect plant survival and growth and could become a major limiting factor for natural regeneration.Therefore,we focused on the adaptive ability of T.sutchuenensis seedlings under three light levels（L0 = full light;L1 = 50% full light;L2 = 25% full light） by comparing their photosynthetic capacity,chlorophyll fluorescence parameters,and chlorophyll content.We found that shading resulted in increases in the apparent quantum efficiency（α） and maximum leaf net photosynthetic rate（Pmax）.At lower light levels,the dark respiration rate（Rd）,light compensation point（LCP）,and light saturation point（LSP） declined.For the chlorophyll fluorescence parameters,PS II primary energy conversion efficiency（Fv/Fm）,PS II potential activity（Fv/Fo）,and photochemical efficiency of PSⅡ in the light（Fv′/Fm′） were significantly higher at lower light levels than at L0,with parameters at L2 higher than at L1.Non-photochemical quenching（NPQ） also had a higher value under shade than under full light,and peaked at L1.With a decrease in light intensity,photochemical quenching（PQ） and the electron transport rate（ETR） decreased.Shading also caused a significant increase in leaf chlorophyll content（Chla ＋ Chlb） per cm2.These results indicate that T.sutchuenensis can tolerate a wide range light conditions,especially low light,and has internal regulatory mechanisms for responding to light level.Therefore,low light under canopy cannot be the decisive limiting factor for natural regeneration of T.sutchuenensis populations.