渗透胁迫及信号处理对海南粗榧叶绿素荧光特性的影响

Effects of Osmotic Stress and Signal Substance Treatment on Chlorophyll Fluorescence Characteristics of Cephalotaxus hainanensis

为了探究甘露醇、氯化钠的渗透胁迫和脱落酸、茉莉酸甲酯、乙烯利、水杨酸等信号物质对海南粗榧(Cephalotaxus hainanensis)叶片叶绿素荧光特性的影响,本研究以海南粗榧新鲜叶片为试材,分别选用甘露醇、氯化钠、脱落酸、茉莉酸甲酯、乙烯利、水杨酸处理海南粗榧叶片,测定PSⅡ实际量子产量Y(Ⅱ)、非光化学淬灭系数(NPQ)、光化学淬灭系数(qP)等叶绿素荧光参数。结果表明:甘露醇处理和氯化钠处理在短时间内可以造成这些参数的波动,然而在24 h后,这些参数趋于平稳,大多数可以恢复到对照水平,但渗透胁迫处理后的Y(Ⅱ)值显著降低,NPQ值却显著升高。在脱落酸、茉莉酸甲酯、乙烯利、水杨酸等信号物质处理后,叶绿素荧光参数多呈现出和甘露醇处理或氯化钠处理相似的趋势,表明了渗透胁迫可能通过不同的信号转导通路影响叶绿素荧光特性,其中水杨酸信号通路可能参与了叶片实际光能转换效率适应调节。

In order to investigate the effect of osmotic stress of mannitol and NaCl and signal substances of abscisic acid,methyl jasmonate,ethephon and salicylic acid on chlorophyll fluorescence characteristics of leaves of Cephalotaxus hainanensis,fresh leaves of Cephalotaxus hainanensis were treated with mannitol,NaCl,abscisic acid,methyl jasmonate,ethephon and salicylic acid,respectively,and determine the actual quantum yield Y(Ⅱ)and non-light of PSⅡ.Chlorophyll fluorescence parameters such as chemical quenching coefficient(NPQ),photochemical quenching coefficient(qP)and so on.The results showed that mannitol and NaCl treatment could cause the fluctuation of these parameters in a short period of time,but after 24 hours,these parameters tended to be stable,most of them could restore to the control level.However,the Y(Ⅱ)value decreased significantly after osmotic stress treatment,while the NPQ value increased significantly.After treatment with signal substances of abscisic acid,methyl jasmonate,ethephon and salicylic acid,chlorophyll fluorescence parameters showed the similar tend as mannitol treatment or NaCl treatment did,suggesting that osmotic stress might affect chlorophyll fluorescence characteristics through different signal transduction pathways.And salicylic acid signaling pathway may be involved in the adaptation regulation of the actual light energy conversion efficiency of leaves.