铜胁迫对鸢尾叶片叶绿素荧光参数的影响

摘要

利用水培试验研究了重金属铜（Cu）胁迫下鸢尾叶片的叶绿素荧光特性，为利用鸢尾处理重金属废水提供理论依据。结果表明，在30 mg/L Cu胁迫下，随着胁迫处理时间延长，鸢尾叶片最大光化学量子产量（Fv/Fm）、相对光合电子传递速率（ETR）先下降后上升，光化学淬灭系数（qP）则先上升后下降，非光化学淬灭系数（qN）一直处于下降趋势；在120 mg/L Cu胁迫下，随着胁迫处理时间延长，鸢尾叶片Fv/Fm、qP持续降低，qN先上升后下降，而 ETR则先下降后上升。可见，30 mg/L Cu对鸢尾叶片光系统Ⅱ反应中心的光化学电子传递有促进作用，而高质量浓度（120 mg/L）Cu会导致PSⅡ反应中心部分关闭。%In order to provide theoretical basis for treating waste water contained heavy metal using Iris tectorum Maxim.,the chlorophyll fluorescence parameters of Iris tectorum Maxim. under Cu stress condition were studied by hydroponics experiment.The results showed that under 30 mg/L Cu stress condition,with the increase of stress time,the efficiency of primary light energy conversion (Fv/Fm)and relative photosynthetic electron transport rate (ETR)of Iris tectorum Maxim.first decreased and then increased,photochemical quenching coefficient(qP)first increased and then decreased,and non-photochemical quenching coefficient (qN ) continuously decreased.Under 120 mg/L Cu stress condition,with the increase of stress time,Fv/Fm and qP continuously decreased,qN first increased and then decreased,and ETR first decreased and then increased.In conclusion,30 mg/L Cu could promote the photochemical electron delivery of PSⅡreaction center,and high concentration(120 mg/L)Cu would cause part of PSⅡ reaction center closed.