近地层臭氧(O3)污染不仅危害人类健康，而且威胁世界环境和粮食安全。作为我国重要商品粮基地的东北地区，近年来日益升高的O3浓度也将对该区粮食安全，尤其是对O3极为敏感的大豆产量和品质产生不良影响。但目前有关O3浓度升高对东北地区大豆生长发育的危害及作用机理的研究很少。本研究拟以我国东北黑土区主栽大豆品种为研究对象，采取模拟实验与定点监测相结合的方法，研究东北大豆对O3浓度升高的响应机制，从叶片形态、产量损失与营养品质三个方面明确品种间的O3敏感性差异，将气孔吸收、光合生理与抗氧化系统结合起来，研究不同O3敏感型品种气孔导度、关键光合酶活性与质外体主要抗氧化剂在不同O3浓度梯度下的变化特征，揭示导致品种间O3敏感性差异的生理生化机制，分析气孔生育期变化规律并参考气孔通量模型，建立东北地区大豆品种气孔O3吸收通量与产量的响应关系，为筛选与培育耐O3大豆品种和评估区域大豆生产O3危害提供科学依据

Tropospheric ozone (O3) is a widespread air pollutant that causes risks for the agricultural production, with soybean (Glycine max L. Mer.) being highly sensitive to this oxidant. In Northeast China, the rapidly increasing trends of O3 precursors suggest that the impacts of current and future O3 on native soybean cultivars may be very signi?cant. To assess O3 sensitivity of local soybean cultivars and explore possible underlying mechanisms, 10-12 native soybean cultivars will be exposed to charcoal-filtered air or elevated O3 in National Field Research Station of Agro-ecosystem in Hailun. This research focuses on (1) identifying the O3 sensitivity among the tested local soybean cultivars based on visible injury, yield loss and nutrient quality of grain; (2) clarifying the possible mechanisms on differential response to O3 between sensitive and tolerant cultivars in terms of stomatal uptake, carbon metabolism process, antioxidant capacity and the combination of these parameters; (3) deriving the relationship between stomatal O3 ?ux and yield loss with the stomatal conductance model.The objectives of the research are to provide (1) materials and theoretical basis for screening and breeding ozone tolerant cultivars; (2) data supporting and theoretical basis for the ozone risk assessment of soybean production in the research region.