《植物生理学报》 2015, 51(7): 1142-1150

高温胁迫下不同热敏感性小麦光化学活性和能量分配差异

张会玲¹, Marian Brestic², Katarina Olsovska², 李刚¹, 孟庆伟¹, 杨兴洪^1,*

¹山东农业大学生命科学学院/作物生物学国家重点实验室, 山东泰安271018; ²Department of Plant Physiology, Slovak Agricultural University, Nitra 94976, Slovak Repulic

通信作者：杨兴洪；E-mail: xhyang@sdau.edu.cn；Tel: 0538-8246167

摘　要：

利用叶绿素荧光技术, 研究高温胁迫下不同热敏感性小麦品种光化学活性和能量分配的差异。结果表明: 在37.5 ℃以上的高温胁迫下, 与热敏感的小麦品种‘Torysa’相比, 耐热品种‘Ilona’通过保持高的PSII最大光化学效率(φ_Po)、捕获的能量向电子传递链传递的效率(ψ_o)以及用于电子传递的量子产额(φ_Eo)使更多的能量被反应中心捕获并进入电子传递链, 而热敏感品种‘Torysa’中较高的用于热耗散的量子比率(φ_Do)表明其更多的能量用于热耗散, 从而使得‘Ilona’中光化学反应可以利用的能量多于‘Torysa’。与此同时, ‘Ilona’还有相对更多的PSI参与环式电子传递, 耗散多余的能量, 从而减少活性氧的产生。因而在高温胁迫下, ‘Ilona’能够维持较高的光化学效率, 降低光抑制, 具有更好的耐热性。

关键词：小麦; 耐热性; 光化学活性; 能量分配

收稿：2015-04-13   修定：2015-05-02

资助：国家自然科学基金(31271634)、国家“863”项目(2012-AA10A309)和山东省自主创新重大关键技术项目(2014-GJJS0201)。

Photochemical Activity and Energy Distribution on Wheat Varieties with Different Heat-Sensitivity under High Temperature Stress

ZHANG Hui-Ling¹, Marian Brestic², Katarina Olsovska², LI Gang¹, MENG Qing-Wei¹, YANG Xing-Hong^1,*

¹College of Life Science, Shandong Agricultural University/State Key Laboratory of Crop Biology, Tai’an, Shandong 271018, China; ²Department of Plant Physiology, Slovak Agricultural University, Nitra 94976, Slovak Repulic

Corresponding author: YANG Xing-Hong; E-mail: xhyang@sdau.edu.cn; Tel: 0538-8246167

Abstract:

The photochemical activity and energy distribution on wheat varieties with different heat-sensitivity were tested by chlorophyll a fluorescence measurement under high temperature stress. The results showed that under temperature higher than 37.5 ℃, ‘Ilona’ (thermo-tolerant variety) maintained higher level of maximum photochemical efficiency of PSII (φ_Po), efficiency with which a trapped exciton can move an electron into the electron transport chain (ψ_o) and the ratio of electron transport flux (φ_Eo) to distribute more energy trapped by reaction center into electron transport chain, while ‘Torysa’ (thermo-sensitive variety) distributed more energy to dissipation by a higher quantum yield of energy dissipation (φ_Do). Compared to ‘Torysa’, ‘Ilona’ had more energy available for photochemistry. Meanwhile, ‘Ilona’ had more PSI involved in the cyclic electron flow and dissipating excess excitation energy. Therefore, under high temperature stress, thermos-tolerant variety ‘Ilona’ maintain higher photochemical activity of PSII, and lower level of photoinhibition than thermos-sensitive variety ‘Torysa’, and thus showed higher thermotolerence.

Key words: wheat; thermotolerance; photochemical activity; energy distribution