《植物生理学报》 2017, 53(10): 1901-1908

臭氧胁迫对葡萄叶片光系统活性的影响及D1蛋白周转的防御作用

邢浩, 郝桂梅, 陈钲文, 孙永江, 翟衡, 杜远鹏^∗

山东农业大学园艺科学与工程学院/作物生物学国家重点实验室, 山东泰安271018

通信作者：杜远鹏；E-mail: duyuanpeng001@163.com

摘　要：

为探究臭氧(O₃)胁迫对葡萄叶片光合电子传递的抑制, 以 ‘赤霞珠’ (Vitis vinifera L. cv. Cabernet Sauvigon)葡萄叶片为试材, 利用Dual-PAM100荧光仪测定O₃胁迫对叶片PSI及PSII光系统活性的影响, 同时配合Handy PEA测量葡萄叶片快速荧光, 结合抑制剂引入分析D1蛋白周转的防御作用。结果表明: O₃胁迫可以显著降低叶绿素最大荧光F_m和最大光化学效率F_v/F_m值, 但最大P₇₀₀信号P_m没有显著变化; 荧光光响应曲线分析表明O₃胁迫下叶片PSII实际光化学活性Y(II)显著降低, 但PSII激发压(1–qP)及非光化学淬灭(NPQ)显著升高, 同时O₃胁迫显著降低了葡萄PSII反应中心吸收的光能用于电子传递的量子产额φ_Eo和单位面积有活性的反应中心的数目RC/CS_o; O₃胁迫也造成了葡萄叶片PSI供体侧限制引起的非光化学能量耗散的量子产量Y(ND)显著升高, 从而导致了PSI实际光化学活性Y(I)的降低。林可霉素(Lin)处理导致O₃胁迫下葡萄叶片F_v/F_m及Y(II)进一步下降, 与对照相比分别降低了28.8%和63.1%, 但Y(I)没有显著变化。由此可知, 臭氧胁迫主要抑制了PSII活性, 并导致PSI电子供体侧受到抑制; 抑制D1蛋白周转可以使臭氧胁迫下葡萄叶片PSII发生严重的破坏, 但PSI活性未受到影响。

关键词：葡萄; 臭氧; D1蛋白; 电子传递; 光抑制; 光保护

收稿：2017-06-16   修定：2017-09-08

资助：国家自然科学基金(31572084)、国家葡萄产业技术体系建设专项(CARS-29-zp-02)、长江学者和创新团队发展计划(IRT15R42)和山东省“双一流”建设奖补资金(SYL2017-YSTD10)。

Effects of ozone stress on the activity of photosystems and on the D1 protein turnover in grape leaves

XING Hao, HAO Gui-Mei, CHEN Zheng-Wen, SUN Yong-Jiang, ZHAI Heng, DU Yuan-Peng^*

State Key Laboratory of Crop Biology, College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an, Shandong 271018, China

Corresponding author: DU Yuan-Peng; E-mail: duyuanpeng001@163.com

Abstract:

In order to investigate the effect of ozone (O₃) stress on the inhibition of photosynthetic electron transport in grape (Vitis vinifera L. cv. Cabernet Sauvigon) leaves, the photosystem I (PSI) and PSII activities in leaves treated with O₃ stress were measured with P₇₀₀ and chlorophyll fluorescence measuring system (Dual-PAM100). Furthermore, the role of D1 protein in protecting photosynthetic apparatus against photodamage was also studied by using the inhibitor and the chlorophyll fast fluorescence O-J-I-P transient. The results showed that the maximum fluorescence F_m and the maximum photochemical efficiency F_v/F_m were significantly decreased in leaves treated with O₃ stress, but the maximum P₇₀₀ signal P_m did not change significantly. Analysis of chlorophyll fluorescence light response curve showed that the actual photochemical activity of leaf PSII [Y(II)] was significantly decreased under O₃ stress, but PSII excitation pressure (1–qP) and non-photochemical quenching (NPQ) increased significantly. O₃ stress also resulted in a significant increase of the yield of the non-photochemical energy dissipation caused by the confinement of the PSI donor side [Y(ND)], resulting in a decrease in the actual photochemical activity of the PSI [Y(I)]. The O-J-I-P test showed that O₃ stress significantly reduced the amount of light energy absorbed by the PSII reaction center for electron transport (φ_Eo) and the number of reaction centers centered on and activity per unit area (RC/CS_o). Lincmycin treatment further decreased the F_v/F_m and Y(II) in grape leaves treated whith O₃ stress, which decreased by 28.8% and 63.1%, respectively, but there was no significant change in Y(I). These results suggested O₃ stress mainly inhibited the PSII activity and the inhibition of PSI electron donor side. The inhibition of D1 protein turnover caused serious damage to the PSII of the grape leaves under O₃ stress, but the PSI activity was not affected.

Key words: grape; ozone; D1 protein; electron transport; photoinhibition; photoprotection