光温交互作用对柑橘植株叶绿素荧光和D1蛋白的影响  

Interacting effects of radiation and temperature on chlorophyll fluorescence and D1 protein in Satsuma mandarin plants.

作　　者：郑洁[1] 郭延平[1] 胡美君[1] 

机构地区：[1]浙江大学农业与生物技术学院园艺系,浙江杭州310029

出　　处：《浙江大学学报（农业与生命科学版）》2008年第6期629-634,共6页Journal of Zhejiang University:Agriculture and Life Sciences

基　　金：国家自然科学基金资助项目(30771497)

摘　　要：利用叶绿素荧光分析、SDS-PAGE电泳和Western-blotting蛋白质印迹技术,研究高光高温交互作用(30℃和1300μmol?m-2?s-1)对3年生温州蜜柑叶片叶绿素荧光特性和D1蛋白水平的影响.试验结果表明,在高温高光条件下生长50 d后,温州蜜柑叶片的总叶绿素、叶绿素a含量及叶绿素a/b值均显著下降,而叶绿素b的含量变化不显著.叶片叶绿素荧光参数的初始荧光Fo升高,而反映光化学效率的Fv/Fm值、光化学猝灭系数qP及光系统Ⅱ(PSⅡ)电子传递能力ΦPSⅡ下降,同时反映热耗散的非光化学猝灭系数qN上升.表观电子传递(ETR)光响应的"光饱和点"和低于200μmol?m-2?s-1光强下的斜率降低.在荧光动力学快相中,反映QA还原活性的(Fi-Fo)/(Fp-Fo)值下降,反映失活的PSⅡ反应中心比例的Fi到Fp的斜率显著增加.此外,PSⅡ反应中心D1蛋白的合成速率小于降解速率,导致D1蛋白的净降解.这些结果说明,高温高光抑制了D1蛋白的修复,致使PSⅡ反应中心失活,电子传递和光化学效率下降.Abstract： Interacting effects of high temperature of 30℃ and high radiation of 1300 μmol·m^-2·s^-1on characteristic of the chlorophyll fluorescence and level of the D1 protein in three-year-old Satsuma mandarin （Citrus unshiu Marc. ） plants were investigated by the chlorophyll fluorescence, SDS-PAGE and Westerwblotting analysis. The results show that contents of total chlorophyll and chlorophyll a, and the chlorophyll a to chlorophyll b ratio in leaves declined markedly under conditions of interaction of high radiation and high temperature for 50 days, while change of the chlorophyll b is not prominent. The initial fluorescence （Fo） increased, photochemical efficiency of PSII （Fv/Fm）, photochemical quenching （qP） and electron transport capacity （φpsⅡ） declined significantly in high irradiation and high temperature treatment plants. Moreover, non-photochemical quenching （qN, reflecting heat dissipation） increased. In addition, light saturation point in response of apparent electron transport rate （ETR） to light intensity and slope of the ETR to photo flux density （PFD） in range of less than 200μmol·m^-2·s^-1 decreased. Fast phase of chlorophyll fluorescence kinetics showed that （Fi--Fo） to （Fp--Fo） ratio reflecting activation of Qa reduction declined, contrarily, slope of Fi to Fp reflecting proportion of inactive PS Ⅱ reaction centers increased. Otherwise, synthetic rate of the D1 protein was slower than its degradation rate resulting in a net reduced content of the D1 protein. These results suggested that under the interaction of high radiation and high temperature conditions, the D1 protein synthesis was inhibited which led to inactive PSⅡ reaction centers, decreased the electron transport and the photochemical efficiency of PS Ⅱ .

关 键 词：温州蜜柑 光系统Ⅱ 叶绿素荧光 D1蛋白 温度 光照 

分 类 号：S666.101[农业科学—果树学] Q945.11[农业科学—园艺学]