植物生态学报 ›› 2016, Vol. 40 ›› Issue (9): 942-951.doi: 10.17521/cjpe.2016.0001

• 方法与技术 • 上一篇    下一篇

调制式荧光影像新技术: 叶片内部最大光化学量子效率及其异质性的活体测定

樊大勇*(), 付增娟, 谢宗强, 李荣贵, 张淑敏   

  1. 中国科学院植物研究所植被与环境变化国家重点实验室, 北京 100093
  • 收稿日期:2015-01-03 接受日期:2016-07-19 出版日期:2016-09-10 发布日期:2016-09-29
  • 通讯作者: 樊大勇 E-mail:fandayong@ibcas.ac.cn
  • 基金资助:
    国家自然科学基金面上项目(31370424)和中国科学院知识创新工程项目(KZCX2-XB3-09)

A new technology of modulated Chl a fluorescence image: In vivo measurement of the PSII maximum photochemical efficiency and its heterogeneity within leaves

Da-Yong FAN*(), Zeng-Juan FU, Zong-Qiang XIE, Rong-Gui LI, Shu-Min ZHANG   

  1. State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
  • Received:2015-01-03 Accepted:2016-07-19 Online:2016-09-10 Published:2016-09-29
  • Contact: Da-Yong FAN E-mail:fandayong@ibcas.ac.cn

摘要:

研究叶片内部光合能力及其异质性, 是光合作用生化模型、光抑制机理、光保护机理等光合生理生态热点问题的重要前提, 但目前缺少可以进行活体测定的装置。该文作者对Vogelmann和Evans (2002)的装置进行了改进, 获得了叶片内部光系统II (PSII)最大光化学量子效率(Fv/Fm)及其异质性影像, 并采用基于Matlab软件自编的图像处理程序对其进行了分析, 研究了不同时间光抑制处理导致的叶内Fv/Fm及其异质性的变化。研究发现: 叶片内部不同层叶肉组织Fv/Fm存在异质性。强光照射导致叶片内部不同层叶肉组织Fv/Fm值下降, 但靠近上表皮的栅栏组织具有较强的抗光抑制能力。光抑制导致叶片内部Fv/Fm异质性的变化, 短期光抑制导致Fv/Fm异质性变大, 这可能与部分叶绿体避光运动相关, 长期光抑制导致Fv/Fm异质性变小, 说明叶绿体避光运动这种光保护机制已经失效。相比于其他类型叶绿素荧光仪, 此装置可以完整获得活体叶片内部Fv/Fm及其异质性影像数据, 这对于系统研究叶片内部光合能力及其异质性机制, 以及为进一步研究一些光合生理生态热点问题提供了有力工具, 具有进一步研发和应用的前景。

关键词: 菠菜, 叶绿素荧光影像, 光抑制

Abstract:
The spatial photosynthetic heterogeneity within leaves is an important prerequisite for the studies on the photosynthetic model, the mechanism(s) of photoinhibition and light protection, etc. However, currently the in vivo measurement of the spatial photosynthetic heterogeneity within leaves is difficult. The present study improved the device assembled by Vogelmann & Evans (2002), thereby acquired the photosystem II (PSII) maximum photochemical efficiency (Fv/Fm) images within leaves. Finally, these images were processed and data of Fv/Fm and its spatial variations could be obtained, with the aid of MATLAB software. Based on the innovative technique, an investigation of the effects of strong light on the Fv/Fm and its spatial heterogeneity within leaves has been carried out. It was found that Fv/Fm within leaves was not homogonous. Strong light led to a general decrease of Fv/Fm (PSII photoinhibition) across leaf section, and the palisade tissue close to the epidermis layer had high tolerance to photoinhibition. Compared with control, short-term photoinhibition caused a larger spatial variation of Fv/Fm within leaves, which may be related to the chloroplast-avoidance response induced by high-fluence. On the contrary, long-term light inhibition led to a smaller spatial variation of Fv/Fm within leaves, indicating such mechanism is no longer effective. Compared to other types of chlorophyll fluoremeter, the device in the present study can in vivo obtain the panoramic picture of Fv/Fm within leaves, providing a powerful tool for the studies on the mechanism(s) attributed to the spatial heterogeneity of photosynthetic capacity of leaf, which is critical for the understanding on several hot spots in the research field of photosynthesis.

Key words: Spinacia oleracea, chlorophyll fluorescence image, photoinhibition