中文摘要：

采用旋转布气法开顶式气室（Open top chambers,OTCs）装置,研究4种臭氧（O3）浓度水平（过滤大气,O3浓度20nl·L^–1;环境大气,O3浓度40nl·L^–1;中等O3浓度处理,O3浓度为75nl·L^–1;高浓度处理,O3浓度为150nl·L^–1）下水稻（Oryzasativa）根系中根系活力、可溶性蛋白含量、膜脂过氧化程度与抗氧化系统的变化差异。主要结果表明与过滤大气处理相比,O3浓度升高（75和150nl·L^–1）使植株根系活力显著降低,根系大幅度、过早地衰退;根系可溶性蛋白质含量显著下降;根系MDA含量显著升高,膜脂过氧化程度加剧;SOD活性呈先升高后下降的变化趋势根系中H2O2含量大幅度显著上升,并随着O3处理浓度升高和暴露时间延长变化幅度增大;CAT与POD活性则表现出升高趋势,但处理后期升高幅度略微降低;整个处理期间根系ASA含量无显著变化。环境大气处理与过滤大气处理植株各个指标变化趋势基本一致并略微下降,随着处理时间延长根系活力与蛋白质含量出现显著下降,其他指标无显著差异。试验结果表明O3浓度升高会对植物地下部分根系产生影响;随着O3胁迫时间的延长,植物将面临着缺乏强有力的根系生理代谢活力支持。

英文摘要：

Aims Our purpose was to investigate the response of soluble protein content, lipid peroxidation and antioxidant system in roots of Oryza sativa to different ozone concentrations. Methods Rice grown in open top chambers in the field were exposed to four ozone concentrations from June 29 to Sept 30, 2007： charcoal-filtered air （CF, 20 nl·L^–1）, non-filtered air （NF, 40 nl·L^–1） and elevated [O3] （75 and 150 nl·L^–1, MO and HO）. We determined root activity, contents of soluble protein, malonaldehyde （MDA）, hydrogen peroxide （H2O2） and ascorbate （ASA）,activities of superoxide dismutase （SOD）, catalase （CAT） and peroxidase （POD）. Important findings Relative to CF, elevated [O3] （MO and HO） significantly decreased root activity and soluble protein content and increased MDA and H2O2 contents and CAT and POD activities with elongated ozone exposure. However, SOD activity was increased in the early period and decreased in the late period with elevated [O3]. Furthermore, ASA content did not show significant difference between MO/HO and CF, except in the 9th week in MO treatment. With the exceptions of root activity and soluble protein content in late growing season, there were no significant differences in investigated variables between NF and CF during the growing season. All results indicated that elevated [O3] has significant effects on rice roots,including short supply of strong, active roots with prolonged ozone exposure.