摘要
【目的】探究在干旱胁迫和复水过程中楸叶泡桐幼苗对光合和叶绿素荧光的生理响应。【方法】本研究以楸叶泡桐幼苗为材料进行盆栽控水试验,以田间持水量的85.00%为对照,测定分析幼苗叶片在干旱胁迫后不同时间和复水后的相对含水量、细胞膜相对透性、光合和叶绿素荧光等的动态变化。【结果】在干旱胁迫后的第4、8、12、16天时,土壤含水量从田间持水量(FC)的85%(对照)分别下降到60.37%、35.96%、23.78%和11.01%;随着干旱胁迫程度的不断增加,叶片的相对含水量(RWC)、蒸腾速率(Tr)、净光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)、最大光化学效率(Fv/Fm)、实际光化学量子效率(ΦPSⅡ)、电子传递速率(ETR)和光化学猝灭系数(qp)均逐渐降低,除干旱胁迫第4天的Tr、Pn、Ci、ΦPSⅡ和ETR外,其它胁迫时期的参数与对照相比均差异显著(P<0.05);随着干旱胁迫程度的不断增加,细胞膜相对透性(RMP)、水分利用效率(WUE)、气孔限制值(Ls)、最小初始荧光(F0)和非光化学猝灭系数(NPQ)均逐渐升高,除干旱胁迫第4天的WUE、Ls和NPQ外,其它胁迫时期的参数与对照相比均差异显著(P<0.05);复水4 d后各指标均得以恢复,且与胁迫第4天相比差异均不显著。【结论】研究表明当土壤含水量低于田间持水量的11.01%时,楸叶泡桐幼苗的叶片干枯脱落,严重影响其正常生长;短期干旱胁迫条件下Ci降低、Ls升高,说明Pn的降低主要是气孔因素导致的。
【Objective】To explore the physiological response of Paulownia catalpifolia to photosynthetic characteristics and chlorophyll fluorescence during the drought stress and rewatering.【Method】The P.catalpifolia seedlings were used as materials for pot experiments in this study,and the dynamic change of the leaf relative water content,relative membrane permeability,photosynthetic characteristics and chlorophyll fluorescence in different time periods after drought stress and rewatering were measured and analyzed with the 85.00%of field capacity(FC)as control.【Result】The research indicates that the soil water content on day 4,8,12 and 16 after drought stress decreased from 85%of field capacity to 60.37%,35.96%,23.78%and 11.01%,respectively;The re lative water content(RWC),transpiration rate(Tr),net photosynthetic rate(Pn),stomatal conductance(Gs),intercellular CO2 concentration(Ci),maximum photochemical efficiency(Fv/Fm),actual photochemical quantum efficiency(ΦPSⅡ),electron transport rate(ETR),photochemical quenching coefficient(qp)are gradually decreased with the increase of drought stress,the significantly differences are showed between the other stress periods and the control except Tr,Pn,Ci,ΦPSⅡand ETR on the fourth day after drought stress(P<0.05);The relative membrane permeability(RMP),water use efficiency(WUE),stomatal limitation value(Ls),initial fluorescence(F0)and non-photochemical quenching coefficient(NPQ)aregradually increased with the increase of drought stress,the significantly differences are showed between the other stress periods and the control except WUE、Ls and NPQ on the fourth day after drought stress(P<0.05);All indexes recover after rewatering,and there is no significantly difference between the fourth day after rewatering and the fourth day after drought stress.【Conclusion】The researches prove that the leaves of P.catalpifolia seedlings dry up and fell off,and their normal growthare seriously affected when the soil water content is below 11.01%FC;Under short-term drought stress,the Ci gradually decreases and Ls gradually increases,which indicate thatthe decrease of Pn is mainly caused by stomatal factor.
作者
冯延芝
赵阳
王保平
段伟
周海江
杨超伟
乔杰
FENG Yanzhi;ZHAO Yang;WANG Baoping;DUAN Wei;ZHOU Haijiang;YANG Chaowei;QIAO Jie(Paulownia R&D Center of State Administration of Forestry and Grassland,Zhengzhou 450003,Henan,China;Non-timber Forestry Research and Development Centre,Chinese Academy of Forestry,Zhengzhou 450003,Henan,China;Key Laboratory of Non-timber Forest Germplasm Enhancement&Utilization of State Forestry Administraion,Zhengzhou 450003,Henan,China)
出处
《中南林业科技大学学报》
CAS
CSCD
北大核心
2020年第4期1-8,共8页
Journal of Central South University of Forestry & Technology
基金
国家林业公益性行业科研专项(201404106)。
关键词
楸叶泡桐
干旱胁迫
复水
光和特性
叶绿素荧光
Paulownia catalpifolia
drought stress
rewatering
photosynthetic characteristics
chlorophyll fluorescence
