《植物生理学报》 2015, 51(6): 969-976

高温、强光下黄瓜叶片PSII供体侧和受体侧的伤害程度与快速荧光参数W_k变化的关系

金立桥, 车兴凯, 张子山, 高辉远*

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

通信作者：高辉远；E-mail: gaohy@sdau.edu.cn；Tel: 0538-8245985

摘　要：

快速荧光OJIP曲线中的W_k参数被广泛作为放氧复合体(OEC)即PSII供体侧伤害的重要指标。然而W_k这一参数的变化不仅受PSII供体侧伤害的影响, 而且还会受到PSII受体侧伤害的影响。很多研究者在使用W_k这个参数时忽略了这个问题。为了阐明PSII供体侧和受体侧伤害程度对Wk影响的规律, 我们通过不同温度和强光处理, 获得不同PSII供体侧和受体侧伤害的黄瓜叶片, 进而分析W_k变化与其供体侧和受体侧伤害程度之间的关系。研究结果表明: 用高温黑暗处理黄瓜叶片后, 其PSII供体侧受到严重的伤害, 此时, W_k随着供体侧伤害程度的增加而显著增加, 在这种情况下, W_k的增加直接反映了OEC的伤害程度; 但是当用强光和高温共同处理黄瓜叶片后, 造成PSII供体侧和受体侧同时伤害时, 如果供体侧的伤害程度大于受体侧的伤害程度时, W_k仍然升高, 然而, 当受体侧的伤害程度大于供体测定伤害程度时, W_k不再显著升高。因此在植物叶片的供体侧和受体共同受到伤害时, 要慎重使用W_k这一参数来判断OEC的伤害程度。本文对W_k在不同供体侧和受体侧伤害条件下的变化规律进行了详细的研究, 并对如何正确使用Wk来反映逆境对植物叶片OEC的伤害程度进行了探讨, 该研究结果可以对正确利用叶绿素快速荧光OJIP分析提供指导。

关键词：快速叶绿素荧光; PSII供体侧; PSII受体侧; 放氧复合体(OEC); W_k

收稿：2015-03-17   修定：2015-04-29

资助：高等学校博士学科点专项科研基金项目(20113702110008)和国家自然科学基金(31370276)。

The Relationship between the Changes in W_k and Different Damage Degree of PSII Donor Side and Acceptor Side under High Temperature with High Light in Cucumber

JIN Li-Qiao, CHE Xing-Kai, ZHANG Zi-Shan, GAO Hui-Yuan*

State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an, Shandong 271018, China

Corresponding author: GAO Hui-Yuan; E-mail: gaohy@sdau.edu.cn; Tel: 0538-8245985

Abstract:

W_k, a parameter of chlorophyll (Chl) a fluorescence OJIP curve, is an important indicator of OEC damages. However, W_k is not only effected by the damage of PSII donor side but also by the damage of PSII acceptor side. Many researchers ignored this fact. To explore the relationship between the changes in W_k and the damage of PSII donor side and acceptor side, we treated leaves of cucumber with different duration of high temperature with high light. We analyzed the relationship between W_k and the damage degree of PSII donor side and acceptor side in leaves of cucumber. Our results demonstrated that when the leaves of cucumber were treated with high temperature in the dark, severe damage of the donor side in leaves occurred. In this situation, W_k increased with the damage degree of the donor side, which directly reflected the damage degree of the OEC. However, when the leaves of cucumber were treated with high light with high temperature, the donor side and the acceptor side were both injured. In this situation, when the damage degree of the donor side was more sever than that of the acceptor side, W_k would still increase; but when the damage degree of the acceptor side was more sever than that of the donor side, W_k would not increase any more. So when the donor side and the acceptor side were both damaged, W_k should be used carefully to reflect the damage degree of OEC. The relationship between changes in W_k and the damage degree of donor side and acceptor side was studied in detail, the conclusion of the study may instruct users of OJIP to use W_k correctly to reflect the damage degree of OEC under stresses.

Key words: chlorophyll a fluorescence transient (O-J-I-P curve); PSII donor side; PSII acceptor side; oxygen-evolving complex (OEC); W_k