脱水和复水过程中金发藓(Polytrichum commune)与湿地匐灯藓(Plagiomnium acutum)叶绿素荧光特性变化的比较研究  

Comparison on Alternation of Chlorophyll Fluoroscence Between Polytrichum commune and Plagiomnium acutum During Dehydration and Rehydration

作　　者：杜晓濛[1] 田向荣[1,2] 李菁[1,2] 石进校[1] 

机构地区：[1]吉首大学生物资源与环境科学学院,中国湖南吉首416000 [2]吉首大学植物资源保护与利用湖南省高校重点实验室,中国湖南吉首416000

出　　处：《生命科学研究》2012年第6期521-525,共5页Life Science Research

基　　金：国家自然科学基金面上项目(30470181);湖南省教育厅优秀青年项目(09B082);湖南省重点学科建设项目(JSU0713Z11);湖南省高校科技创新团队支撑计划项目(201208Z02)

摘　　要：以来自不同水分生境的金发藓(Polytrichum commune)和湿地匐灯藓(Plagiomnium acutum)为材料,利用叶绿素荧光成像技术比较了脱水和复水过程中两种藓类的荧光光响应曲线、光系统Ⅱ光能转化效率(ratio ofchlorophyll variation fluorescence,Fv/Fm)、光系统Ⅱ光量子产量(quantum yielding of PSⅡ,Y(Ⅱ))、光化学猝灭(photochemical quenching,qP)和非光化学猝灭(none-photochemical quenching,NPQ)的变化.结果显示,在脱水过程中,金发藓的抑制光强可维持在800μmol/(m2.s)以上,而湿地匐灯藓可低至400μmol/(m2.s)左右;金发藓ETR(electron transportation rate)值始终可维持在20附近,而湿地匐灯藓可降至0;两种藓类的Fv/Fm、Y(Ⅱ)、qP均下降,但金发藓较湿地匐灯藓高;NPQ先升后降,金发藓的峰值早于湿地匐灯藓,而幅度低于湿地匐灯藓.在复水过程中,两种藓类抑制光强和ETR均迅速恢复后略有下降,金发藓的恢复较湿地匐灯藓慢但波动小;两种藓类Fv/Fm和Y(Ⅱ)均能恢复到正常水平,金发藓均高于湿地匐灯藓;两种藓类qP略有上升,NPQ则略有下降.说明藓类植物对脱水伤害的耐受能力主要体现在复水的修复能力上,而脱水持续和程度会对不同生境的藓类产生不同的胁迫效应.从光保护能力的角度来看,生活于易产生水分亏缺条件下的金发藓比生活在水分充沛条件下的湿地匐灯藓具有更强的脱水耐受能力.Polytrichum commune from relative drought habitat and Plagiomnium acutum from wet habitat were used as materials,and their chlorophyll fluroscence characteristics,such as ETR-PAR（Photosyntheti-cally Active Radiation-electron transportation rate） light respond curves,Fv/Fm（ratio of chlorophyll variation fluorescence）,Y（Ⅱ）（quantum yielding of PSⅡ）,qP（photochemical quenching） and NPQ（none-photochemi-cal quenching） in diferent dehydration and rehydration treatments were detected by IMAGING-PAM analyzer（WALZ）.In the procedure of desiccation,P.commune could sustain a higher inhibit light intensity（over 800 μmol/（m2·s）） and a stable ETR value（about 20）,but inhibit light intensity of P.acutum menifested a dramatic decline and decreased to about 400 μmol/（m2·s）,and ETR value could be inhibited to null.Fv/Fm,Y（Ⅱ）,qP of both two bryophyta species displayed a drop trends,nevertheless,P.commune contain a higher value.NPQ of two bryophytes manifested an obvious peak,and the peak of P.commune occured early and possess a lower alternative range.In the process of rehydration,inhibit light intensity and ETR value of both species recover rapidly,and P.commnue menifested slowly and was provide with less alternation.Fv/Fm,Y（Ⅱ） of both species recover to normal state,and values of P.commune was higher.Results indicated that desiccation tolerance of bryophytes primarily rely on the repair ability in recovery process.But bryophytes from diferent habitat should reflect distinct response on desiccation,P.commune from relative drought habitat possess stronger desicccation tolerance than P.acutum from wet habitat.

关 键 词：脱水与复水 叶绿素荧光光响应曲线 光系统Ⅱ光能转化效率 光系统Ⅱ光化学量子效率 光化学猝灭系数 非光化学猝灭系数 

分 类 号：Q945.79[生物学—植物学]