《植物生理学报》 2015, 51(2): 246-252

气体甲醛胁迫对蚕豆保卫细胞中过氧化氢的积累和气孔导度及开度的影响

孙慧群^1,2, 周升恩¹, 吴怀胜¹, 李昆志¹, 陈丽梅^1,*

¹昆明理工大学生命科学与技术学院, 昆明呈贡650500; ²安庆师范学院资源环境系, 安徽安庆246011

通信作者：陈丽梅；E-mail: chenlimeikm@126.com；Tel: 0871-65920213

摘　要：

以蚕豆为材料, 考察气体甲醛(HCHO)胁迫对保卫细胞H₂O₂积累和叶片气孔导度、开度的影响。结果表明: 气体HCHO胁迫增加了叶片中H₂O₂的积累, 荧光显微分析发现在较低浓度(0.2~0.4 μmol•L^-1)气体HCHO胁迫下, 保卫细胞中增加的H₂O₂主要分布在细胞质中, 高浓度(0.8~1.6 μmol•L^-1)气体HCHO胁迫不仅增加保卫细胞质中H₂O₂的积累, 而且显著增加叶绿体中H₂O₂的含量及积累H₂O₂的叶绿体数量, 这说明在高浓度气体HCHO胁迫下蚕豆保卫细胞中增加的H₂O₂主要来源于叶绿体和细胞质。保卫细胞中H₂O₂积累的增加显著降低蚕豆的气孔导度和开度, 从而导致蚕豆HCHO吸收效率下降。气体HCHO胁迫下叶片中抗氧化酶活性的变化可能是H₂O₂积累增加的主要原因, 气体HCHO胁迫显著增强叶片中CAT和SOD的活性, 但只有低浓度HCHO胁迫诱导叶片POD活性, 叶片APX对HCHO胁迫很敏感, 低浓度的气体HCHO对叶片APX活性都有显著的抑制作用。

关键词：气体甲醛胁迫; 蚕豆; 保卫细胞; 过氧化氢积累; 抗氧化酶

收稿：2014-12-15   修定：2015-01-26

资助：国家自然科学基金(30970263)。

Effects of Gaseous Formaldehyde Stress on the Accumulation of Hydrogen Peroxide in Guard Cells and the Stomata Conductance and Aperture of Vicia faba

SUN Hui-Qun^1,2, ZHOU Sheng-En¹, WU Huai-Sheng¹, LI Kun-Zhi¹, CHEN Li-Mei^1,*

¹Faculty of Life Science and Biotechnology, Kunming University of Science and Technology, Chenggong, Kunming 650500, China; ²Department of Resource and Environment, Anqing Normal College, Anqing, Anhui 246011, China

Corresponding author: CHEN Li-Mei; E-mail: chenlimeikm@126.com; Tel: 0871-65920213

Abstract:

Using Vicia faba as the material, effects of gaseous formaldehyde (HCHO) stress on the accumulation of H₂O₂ in guard cells, the stomata conductance and aperture were investigated. The results showed that the gaseous HCHO stress increased the accumulation of H₂O₂ in leaves. The fluorescence microscopic analysis indicated that the increased H₂O₂ in guard cells mainly distributed in the cytoplasm under low levels (0.2–0.4 μmol•L^-1) of gaseous HCHO stress. High levels (0.8–1.6 μmol•L^-1) of gaseous HCHO stress significantly increased not only the accumulation of H₂O₂ in the cytoplasm of guard cells but also the content of H₂O₂ in chloroplasts and the number of H₂O₂-accumulated chloroplasts. The data suggested that the accumulated H₂O₂ in guard cells mainly originated from chloroplasts and the cytoplasm under high levels of gaseous HCHO stress. The accumulation of H₂O₂ in guard cells significantly decreased the stomatal conductance and aperture, leading to a decline in the HCHO absorption efficiency of V. faba. The accumulation of H₂O₂ in leaves might originate from the changes of antioxidant enzyme activities in leaves under gaseous HCHO stress. The gaseous HCHO stress significantly enhanced the activitkies of CAT and SOD in leaves. However, only low levels of gaseous HCHO induced the activity of POD. APX was sensitive to HCHO stress and even a low level of HCHO stress could inhibit its activity remarkably.

Key words: gaseous formaldehyde stress; Vicia faba; guard cell; H₂O₂ accumulation; antioxidant enzyme