Liu Xiaofang, Hou Fen, Li Guangke, Sang Nan
College of Environment and Resource, Research Center of Environment and Health, Shanxi University, Taiyuan 030006, China.
College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
J Environ Sci (China). 2015 Aug 1;34:93-9. doi: 10.1016/j.jes.2015.03.011. Epub 2015 Jun 3.
Nitrogen dioxide (NO2) is one of the most common and harmful air pollutants. To analyze the response of plants to NO2 stress, we investigated the morphological change, reactive oxygen species (ROS) production and antioxidant enzyme activity in Arabidopsis thaliana (Col-0) exposed to 1.7, 4, 8.5, and 18.8 mg/m(3) NO2. The results indicate that NO2 exposure affected plant growth and chlorophyll (Chl) content, and increased oxygen free radical (O2(-)) production rate in Arabidopsis shoots. Furthermore, NO2 elevated the levels of lipid peroxidation and protein oxidation, accompanied by the induction of antioxidant enzyme activities and change of ascorbate (AsA) and glutathione (GSH) contents. Following this, we mimicked nitric acid mist under experimental conditions, and confirmed the antioxidant mechanism of the plant to the stress. Our results imply that NO2 and its acid mist caused pollution risk to plant systems. During the process, increased ROS acted as a signal to induce a defense response, and antioxidant status played an important role in plant protection against NO2/nitric acid mist-caused oxidative damage.
二氧化氮（NO₂）是最常见且有害的空气污染物之一。为分析植物对NO₂胁迫的响应，我们研究了暴露于1.7、4、8.5和18.8 mg/m³ NO₂环境下的拟南芥（Col-0）的形态变化、活性氧（ROS）产生及抗氧化酶活性。结果表明，暴露于NO₂会影响植物生长和叶绿素（Chl）含量，并提高拟南芥地上部的氧自由基（O₂⁻）产生速率。此外，NO₂会提高脂质过氧化和蛋白质氧化水平，同时诱导抗氧化酶活性，并改变抗坏血酸（AsA）和谷胱甘肽（GSH）含量。在此之后，我们在实验条件下模拟硝酸雾，并证实了植物对该胁迫的抗氧化机制。我们的结果表明，NO₂及其酸雾对植物系统造成了污染风险。在此过程中，增加的ROS作为信号诱导防御反应，而抗氧化状态在植物抵御NO₂/硝酸雾引起的氧化损伤中发挥了重要作用。
