构树叶片叶绿素荧光诱导动力学特征的季节变化 生物学专业VIP免费

摘要为了探明季节变化对构树生长发育的影响，本实验利用Junior-PAM（Walz,Germany）测量并比较了野生构树在春夏秋3季的叶绿素荧光参数的差异。研究结果表明：1)在190μmol(photons)m-2s-1下最大量子产量Fv/Fm在春季（0.82）与夏季（0.78）间差异不显著，秋季（0.55）时显著降低，这与625μmol(photons)m-2s-1以及1,500μmol(photons)m-2s-1下的显著性差异情况相同；2）190μmol(photons)m-2s-1下，光化学猝灭系数qP在春（0.60）夏（0.70）秋（0.78）均存在显著差异且不断升高，非光化学猝灭系数NPQ在春（0.82）夏（0.52）秋（0.46）均存在显著差异且不断降低，625μmol(photons)m-2s-1以及1,500μmol(photons)m-2s-1下的显著性差异情况与前者相同，表明植物积累光损伤后耗散过剩光能为热能的能力不断下降；3）在625μmol(photons)m-2s-1下调节性能量耗散的量子产量ΦNPQ在春（0.47）夏（0.39）秋（0.36）不断下降，表明光保护能力不断下降，非调节性能量耗散的量子产量ΦNO在秋季（0.44）显著升高，表明光损伤不断升高，其他两个光化光强度下显著性结果相似；4）最小饱和光强Ek在三个季节间均存在显著差异，其中夏季（694.86）最低，春季（898.45）大于秋季（1047.11）；5）光响应曲线的初始斜率α在三个季节间均存在显著差异，其中夏季（0.14）最高，春季（0.11）大于秋季（0.82）。本研究为华中、华东地区的构树种植提供了理论依据。关键词：叶绿素荧光参数；构树；季节变化；生态适应AbstractInordertoascertaintheinfluenceofseasonalchangesonthegrowthanddevelopmentofBroussonetiapapyrifera,thedifferencesinthechlorophyllfluorescenceparametersofthewildBroussonetiapapyriferaduringthespring,summer,andautumnseasonsweremeasuredandcomparedusingJunior-PAM(Walz,Germany).Theresultsshowthat:1)ThemaximumquantumyieldFv/Fmat190μmol(photons)m-2s-1isnotsignificantlydifferentbetweenspring(0.82)andsummer(0.78),butissignificantlyloweratautumn(0.55).Significantdifferencewasfoundbetweenμmol(photons)m-2s-1and1,500μmol(photons)m-2s-1;2)PhotochemicalquenchingcoefficientqPat190μmol(photons)m-2s-1inspring(0.60),autumn(0.70)andautumn(0.78)allshowedsignificantdifferencesandincreasedcontinuously.Thenon-photochemicalquenchingcoefficientNPQhadasignificantdifferenceinthespring(0.82),summer(0.52),autumn(0.46)anddecreasedcontinuously,625μmol(photons)m-2s-1and1,500μmol(photons)m-2s-1issignificantdifferenceinthesameasformer,indicatingthattheabilityofplantstodissipateexcesslightenergyaslightenergyafterphotodamagedecreasescontinuously;3)At625μmol(photons)m-2s-1,thequantumyieldofΦNPQdissipatedbydecreasescontinuouslyduringthespring(0.47),summer(0.39)andautumn(0.36),indicatingthatthephotoprotectioncapabilityiscontinuouslydegradedandthequantumyieldofnon-adjustedenergydissipationisdecreased.ΦNOincreasedsignificantlyinautumn(0.44),indicatingthatlightdamageiscontinuouslyrising,theothertwosignificantresultsundertheactiniclightintensityweresimilar;4)TheminimumsaturatedlightintensityEkwassignificantlydifferentamongthethreeseasons,withthelowestinsummer(694.86),andgreaterinautumn(1047.11);5)Theinitialslopeαinthelightresponsecurvehadasignificantdifferenceamongthethreeseasons,withsummer(0.14)beingthehighestandautumn(0.82)beingthelowest.ThisstudyprovidesatheoreticalbasisforthetreeplantingincentralandeasternChina.Keywords：Chlorophyllfluorescenceparameters;Broussonetiapapyrifera;Seasonalchanges;Ecologicaladaptation1.引言构树（Broussonetiapapyrifera）为桑科（Moraceae）构属（Broussonetia）木本植物，是一种生态型经济树种，在我国除东北及西北北部寒冷区域外，其他地区均有分布，在我国黄河流域以南，特别是贵州、广西、云南等地分布较为...