茄子光系统Ⅱ的热胁迫特性  

Heat stress characteristics of photosystem Ⅱ in eggplant

作　　者：王梅[1] 高志奎[1] 黄瑞虹[1] 王惠英[1] 张文丽[1] 高荣孚[2] 

机构地区：[1]河北农业大学园艺学院,河北保定071001 [2]北京林业大学生物科学与技术学院,北京100083

出　　处：《应用生态学报》2007年第1期63-68,共6页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金项目(30571267);国家科技攻关计划资助项目(2004BA525B14).

摘　　要：以耐热性较弱的黑贝一号圆茄和耐热性较强的黑贝二号圆茄为试材,热胁迫处理后采用植物效率仪PEA进行快速叶绿素荧光诱导曲线及其参数测定.结果表明:当温度高于40℃,PSⅡ结构受热胁迫影响较为敏感,表现为初始荧光Fo缓慢上升;PSⅡ原初光化学效率Fv/Fm和ΔF/Fm′大幅度下降,且黑贝二号Fv/Fm的半衰时间T50和ΔF/Fm′的半衰温度t50分别大于黑贝一号.较高的热胁迫剂量(48℃处理5min或44℃处理20～30min)下,快速荧光诱导动力学曲线呈现OKJIP型,在700μs处出现与放氧复合体失活有关的K相.黑贝一号在44℃下处理20min才有K相出现,黑贝二号则晚10min出现.与35℃相比,在48℃,特别是在52℃的较高剂量热胁迫下,Strasser能量流动模型参数中的DIo/RC有大幅度地增加,体现了热耗散对PSⅡ的较强保护能力.随着热胁迫温度的升高和热胁迫时间的延长,两品种的无活性中心Fvi/Fv显著增加.With lower-and higher heat-resistant varieties of eggplant （ Solanum melongena L. ） Heibei Ⅰand Heibei Ⅱ as test materials, and by using Plant Efficiency Analyzer （PEA） from Hansatech, this paper measured the fast chlorophyll a fluorescence transient and its parameters. The results showed that PS Ⅱ construction became more sensitive to heat stress when ambient temperature was higher than 40 ℃. The Fo went up slowly, and Fv/Fm and △F/Fm′ came down dramatically. Heibei Ⅱ had a longer semi-attenuation temperature of Fv/Fm （T50） and △F/Fm′ （ t50 ） than Heibei Ⅰ. Under strong heat stress （5 min at 48 ℃ or 20 - 30 min at 44 ℃ ） , the K-step in relation to the inactivation of oxygen-evolving complex appeared in fluorescence rise at about 700 μs, and the regular O-J-I-P transient was transformed to O-K-J-I-P one. The K-phase of Heibei Ⅰ and Heibei Ⅱ appeared when the treatment time was up to 20 and 30 minutes at 44 ℃, respectively. In comparing with 35 ℃ heat treatment, the DIo/RC in the parameters of Strasser＇s specific energy fluxes model was increased by a great extent under 48 ℃ or more heat stress, reflecting a strong safeguard of energy dissipation to PS Ⅱ. When the temperature of heat stress increased from 35 ℃ to 52 ℃, the Fvi/Fv, of PS Ⅱ silent reaction centers of Heibei Ⅰ and Heibei Ⅱ increased remarkably.

关 键 词：热胁迫 叶绿素荧光参数 光系统Ⅱ 茄子 

分 类 号：S641.1[农业科学—蔬菜学]