资源描述：
《干旱胁迫对胡杨光合和叶绿素荧光参数的影响》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、西北林学院学报2009,24(4):5～9JournalofNorthwestForestryUniversity干旱胁迫对胡杨光合和叶绿素荧光参数的影响33周朝彬,宋于洋,王炳举,李荣,李明艳,李园园(石河子大学农学院,新疆,石河子,832000)摘要:以1a生胡杨实生苗为材料,采用盆栽实验研究了不同保水剂处理下幼苗的叶片水势、光合和叶绿素荧光参数的变化,并探讨了胡杨对干旱胁迫的适应机制。结果表明,随着保水剂用量的减少,土壤水分含量降低,水吸力上升,干旱胁迫加重,叶片水势,Pnmax,AQY,LSP,Pn,WUE,Gs,Tr随着干旱胁迫的加重而降低,Ci则呈上升趋势。表明胡杨Pn
2、的下降是由于非气孔限制因素。土壤水分的变化对Chl(a+b),LCP和Rd无影响。不同干旱胁迫条件下,Pn,WUE,Gs,Tr随光强的增加而上升趋势,Ci则呈下降趋势。Fv/Fm,Fv/Fo,ΦPSⅡ,ETR和qP随着干旱胁迫的降低而上升趋势,NPQ则呈下降趋势。说明增加保水剂用量可以降低干旱胁迫,从而提高光能捕获率、光合电子传递活性和光能转化成化学能的效率。随着保水剂用量的降低,干旱胁迫加重造成光抑制,增加的NPQ表明多余的光能以热的形式耗散掉,防止了光合器官的破坏。关键词:干旱胁迫;保水剂;胡杨;光合;叶绿素荧光中图分类号:S718.43文献标识码:A文章编号:10012746
3、1(2009)0420005205EffectsofDroughtStressonPhotosynthesisandChlorophyllFluorescenceParametersofPopuluseuphratica3ZHOUChao2bin,SONGYu2yang,WANGBing2ju,LIRong,LIMing2yan,LIYuan2yuan(CollegeofAgriculture,ShiheziUniversity,Shihezi,Xinjiang832000,China)Abstract:Populuseuphraticaisanimportanttreespeci
4、esofdesertriparianforest.Thispaperstudiedtheresponseofleafwaterpotential,soilwatersuction,photosynthesisandchlorophyllfluorescenceparametersofone2year2oldseedlingsofP.euphraticatreatedbydifferentwater2retainingagentcontents,aswellastheirphysiologicaladaptivemechanismstodroughtstress.Theresults
5、showedthatthesoilwatercontentdecreased,andsoilwatersuctionincreasedwiththedecreasedofwater2retainingagentcontent,thenthedroughtstressincreased.Withthewaterstressincreased,leafwaterpotential,Pnmax,AQY,LSP,Pn,WUE,GsandTrreducedandtheCiincreased,whichshowedthatthedeclinedPncausedbynonstomatallimi
6、tation.WaterstresswasnoneffectivetotheChl(a+b),LCPandRd.Withthephotonsfluxdensityenhanced,thePn,WUE,GsandTrincreased,buttheCireduced.Withthedroughtstressdecreased,Fv/Fm,Fv/Fo,ΦPSⅡ,ETRandqPincreased,buttheNPQreduced,whichindicatedthatwiththedroughtstressdecreased,theefficiencyoflightenergycaptu
7、re,activityofelectrontransportandphotochemicalquantumefficiencyincreased.Withthewaterstressincreased,thephoto2inhibitionappeared,theincreasedNPQilluminatedthecounteractedphoto2inhibitionandprotectedstructuresbyimprovingthermaldissipa2ti
