东北山樱桃叶绿素荧光对外源化感物质的响应

Response of Cerasus sachalinensis chlorophyll fluorescence to exogenous allelochemical

以东北山樱桃实生幼苗为试材,利用Hansatch PEA,采用叶绿素荧光诱导动力学理论和JIP-test数据分析方法,研究对羟基苯甲酸对叶片叶绿素荧光参数的影响。结果表明:幼苗在不同浓度对羟基苯甲酸(0.1、1、10 mmol·L-1)处理下的叶片光合性能指数、捕获的激子将电子传递到电子传递链中QA-下游的其他电子受体的概率、用于电子传递的量子产额和单位面积有活性的反应中心数目较对照均有所下降;PSⅡ最大量子效率、单位面积有活性的反应中心数目几乎没有变化;而PSⅡ受体侧的电子受体库容量则高于对照,且呈"上升—下降"趋势。天线色素吸收的能量在低浓度下有小幅升高,反应中心捕获的能量、用于电子传递的能量及用于热耗散的能量则无明显变化。可见,对羟基苯甲酸对东北山樱桃叶片光合结构的不同部位产生影响,进而降低光合性能,影响光合作用。

The effects of para-hydroxybenzoic on chlorophyll fluorescence parameters in seedlings of Cerasus sachalinensis were studied through Plant EfficiencyAnalyzer Hansatch PEA.The results showed that with different concentrations（0.1,1,10 mmol·L^-1）of para-hydroxybenzoic acid treatments,Photosynthetic characteristics in leaf,Probability of transferring electrons to other electron acceptors in downstream of QA through electron transport chain,quantum yield for electron transport and density of RC（RC/CSm）were all decreased in comparison to control.The maximum quantum efficiency of PSII（φpo）,density of RC（RC/CS0）hardly varied, whereas that normalised total complementary area above the O-J-I-P transie（Sm）increased.In addition,absorption flux per CS（ABS/ RC）increased,trapped energy flux per CS（TRo/RC）,election transport flux per RC（ETo/RC）and dissipated energy flux per RC （DIo/RC）hardly varied.These results demonstrate that para-hydroxybenzoic acid effect photosynthesis by affecting different positions in photosynthesis of Cerasus sachalinensis and decrease the performance of photosynthesis.