摘要
以浮萍(Lemnaminor L.)为实验材料,使用水下调制荧光仪研究不同镉浓度(0、1、2、4、6、8和10mg·L-1)条件下浮萍叶绿素荧光的变化和叶绿素含量的变化,探讨了镉对浮萍生长和光合作用的影响.结果表明,镉胁迫导致浮萍最大光化学量子产量(Fv/Fm)、光系统Ⅱ(PSⅡ)有效量子产量(ФPSⅡ)、光化学淬灭(qP)、相对电子传递速率(rETR)、质体醌库(Fv/2)下降,非光化学淬灭(qN)和PSⅡ水裂解端失活程度(Fo/Fv)上升,说明浮萍的PSⅡ光合活性受到镉胁迫抑制.对浮萍叶绿素含量的测定结果表明,浮萍叶绿素含量明显下降,并且叶绿素a的下降幅度大于叶绿素b;同时,浮萍PSⅡ水裂解程度(Fo/Fv)对于镉胁迫反应极为灵敏,因而可以作为金属胁迫的重要指标.
The chlorophyll fluorescence parameters and chlorophyll content of Lemna minor L. were measured under different concentrations of cadmium (0、1、2、4、6、8 and 10 mg·L-1). The results showed that the maximum quantum yield (Fv/Fm) 、effective quantum yield (ФPSⅡ) 、photochemical quenching (qP) 、photosynthetic electron transport (rETR) and plastoquinone pool (Fv/2) decreased,while the non-photochemical quenching (qN) and water-splitting apparatus inactivation extent (Fo/Fv) increased under cadmium stress. Furthermore,the chlorophyll content decreased significantly and chlorophyll a decreased more than chlorophyll b. All these results suggested that the photosynthetic activities of PSⅡ system for Lemna minor were inhibited under cadmium stress. Fo/Fv,most sensitive to cadmium,could be a useful indicator of heavy metal-stress.
出处
《环境科学学报》
CAS
CSCD
北大核心
2010年第5期1062-1068,共7页
Acta Scientiae Circumstantiae
基金
上海市博士后科研资助计划(No.08R214120)~~
关键词
浮萍
镉胁迫
叶绿素荧光指标
叶绿素含量
Lemna minor L.
cadmium stress
chlorophyll fluorescence
chlorophyll content