茄子离体叶片光系统Ⅱ的冷激胁迫效应及热力学分析  

Studies on Cold Shock Stress Effect of Photosystem Ⅱ and Its Thermodynamics Analyse in Eggplant

作　　者：王梅[1] 高志奎[1] 黄瑞虹[1] 吕桂云[1] 张文丽[1] 杜爽[1] 

机构地区：[1]河北农业大学园艺学院,河北保定071001

出　　处：《园艺学报》2009年第2期261-266,共6页Acta Horticulturae Sinica

基　　金：国家自然科学基金项目(30571267);国家科技攻关计划项目(2004BA525B14);河北省农业综合开发科技推广项目(2007)

摘　　要：以耐冷性较强的‘短把黑’圆茄和耐热性较强的‘黑帅’圆茄为试材,经冷激胁迫后采用植物效率仪,进行快速叶绿素荧光参数测定,并利用最大光化学效率Fv/Fm和活性中心RC/CSo的标准状态变性自由能变△GD进行PSⅡ冷稳定性的热力学分析。随着冷激胁迫温度的降低和时间的延长,PSⅡ的Fv/Fm、实际光化学效率ΔF/Fm′、RC/CSo呈下降趋势;单位反应中心DIo/RC和非光化学猝灭qN呈上升趋势;反映出冷激胁迫下PSⅡ反应中心的可逆失活和依赖于叶黄素循环的热耗散的双重机制在保护PSⅡ防止光抑制中起到重要作用。通过两品种间PSⅡ行为差异,本研究引入了两组新的参数作为便于直观比较冷胁迫的评价指标。黑帅圆茄Fv/Fm、ΔF/Fm′的半衰温度T1/2和t1/2值分别高于短把黑圆茄1.4℃和0.8℃。茄子叶片Fv/Fm和RC/CSo的△GD随着冷激胁迫温度的降低而减少呈瀑布型的下降趋势。黑帅圆茄的△GD值和变性中点温度Tm都低于短把黑圆茄。它们均反映出黑帅圆茄的耐冷性低于短把黑圆茄。Fast chlorophyll fluorescence parameters were measured in two varieties of eggplants, ＇Duanbahei＇ with cold resistance and ＇ Heishuai＇ with heat resistance by plant efficiency analyzer （PEA）. Also the thermodynamics analyse of PS Ⅱ cold shock stability were studied by using the standard stade denaturalization Gibbs free energy variation △GD of the maximal photochemical efficiency of photosystem Ⅱ （Fv/Fm） and reaction centers RC/CSo. With the temperature decreasedand time extended, the Fv/Fm, factual photochemistry efficiency ΔF/Fm′and RC/CSo of PSⅡ downtrend. The exhibition of the energy dissipation DIo/RC and the nonphotoehemieal quenching coefficient qN ascends. The generalized analysis reflected the dual mechanism under the cold shock, the reversible deactivation of PS Ⅱ reaction centers and the energy dissipation which depended on lutein circulation were important in protecting PS Ⅱ for preventing photoprohibition. Moreover, two groups of new parameters were introduced as index for comparing cold shock easily through the different PS Ⅱ action of two varieties. Semi-attenuation temperature T1/2 and t1/2 of Heishuai were 1.4℃ and 0. 8 ℃higher than that of Duanbahei. The △GD of the Fv/Fm and RC/CSo in the leaves of eggplant downtrend as waterfall with the cold shock temperature decreased. The △GD and the denaturalization midpoint temperature Tm of Heibei were lower than Duanbahei. The result showed the cold resistance of Heishuai is lower than Duanbahei.

关 键 词：茄子 冷激胁迫 叶绿素荧光参数 光系统Ⅱ 吉布斯自由能 

分 类 号：S641.1[农业科学—蔬菜学]