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以耐光氧化品种粳稻02428和对光氧化敏感品种籼稻3037为材料，在不同的光子通量密度（PFD）、O2浓度和CO2浓度的条件下，测定碳酸酐酶（CarbonicAnhydrase，CA）活性、光合系统（Photosvs－temⅡ，PSⅡ）活性和光合速率。结果表明，粳稻02428和籼稻3037叶片在光抑制条件下，CA活性都有明显增加；光合CO_2固定的动力学分析显示Km值随着PFD的增加及CO_2和O_2浓度的减少而减小，说明CA活性的增加减小了Km值，增加了对CO_2的亲和力和光合CO_2固定能力。进一步用CA专一性抑制剂处理证明，CA活性的增加有减轻PSⅡ和光合光抑制的作用。
The photosynthetic system (Carbonic Anhydrase, CA) activity and photosynthetic rate were measured under different photon flux density (PFD), O2 concentration and CO2 concentration with the photosynthetic antioxidant rice variety 02428 and the photooxidation sensitive variety indica rice 3037 as materials. (Photosvs-tem Ⅱ, PS Ⅱ) activity and photosynthetic rate. The results showed that the activities of CA in rice 02428 and indica rice 3037 were significantly increased under photoinhibition conditions. The kinetic analysis of photosynthetic CO_2 fixation showed that the Km value decreased with the increase of PFD and the decrease of CO_2 and O_2, indicating that CA Increased activity reduced Km, increased affinity for CO 2 and photosynthetic CO 2 fixation. The further treatment with CA-specific inhibitors proved that the increase of CA activity could alleviate the inhibition of PSⅡ and photosynthesis.