Abstract Rice plants cultivated under 700 ppm atmospheric CO2 concentration presented a reduction in the progress and severity of the brown spot disease (Bipolaris oryzae), through the enhancement of biochemical defense mechanisms. Plants exposed to 700 ppm of CO2 had higher activity of the enzymes superoxide dismutase, catalase, ascorbate peroxidase, peroxidase, polyphenoloxidase and chitinase, and increased phenolic compounds and lignin concentration, independent of the rice cultivar. Therefore, the lower severity values of the disease were related to changes in the development of the lesions as a result of the defense responses, which were stimulated in the rice plants by the increase of CO2 concentration.

中文翻译：

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大气 CO2 浓度高时，水稻对稻瘟病的生化防御能力增强

摘要 在 700 ppm 大气 CO2 浓度下栽培的水稻植株通过增强生化防御机制，降低了褐斑病（Bipolaris oryzae）的进展和严重程度。暴露于 700 ppm CO2 的植物具有更高的酶超氧化物歧化酶、过氧化氢酶、抗坏血酸过氧化物酶、过氧化物酶、多酚氧化酶和几丁质酶的活性，并且酚类化合物和木质素浓度增加，与水稻品种无关。因此，疾病的较低严重度值与作为防御反应的结果的病变发展的变化有关，该反应在水稻植株中受到 CO2 浓度增加的刺激。