The foliar photosynthetic acclimation to prolonged elevated CO₂ has been studied in many ways, but the quantification of photosynthetic acclimation through the limitation of stomatal conductance (g_s), mesophyll conductance (g_m) and biochemical capacity (V_camx) is scarce. To quantify photosynthetic acclimation under elevated CO₂, a japonica rice cultivar ‘Nanjing 9108’ was grown at two CO₂ levels—ambient CO₂ (a[CO₂]) and a[CO₂] +200 μmol mol⁻¹ (e[CO₂]) using open top chamber facility. We measured the response of net photosynthetic rate (A_n) to CO₂ at Rubisco (C_c) at jointing, flowering and filling stages based a biochemical C3‐photosynthesis model. Measurements at the same CO₂ concentration showed that the A_n under e[CO₂] was significantly lower than that under a[CO₂] at three developmental stages, suggesting the occurrence of acclimation of photosynthesis. The photosynthetic acclimation is associated with the decrease in g_m, g_s and V_cmax, and g_m mainly limits photosynthesis. The contribution of g_m, g_s and V_camx limitation to photosynthetic acclimation averaged 65 %, 25 % and 10 % of the total reduction in A_n. Our findings demonstrate g_m is the major driver of photosynthetic acclimation and highlight the role of g_m under e[CO₂] in rice.

已经通过多种方式研究了叶面光合适应长期升高的 CO ₂，但通过限制气孔导度 ( g _s )、叶肉导度 ( g _m ) 和生化能力 ( V _camx ) 来量化光合驯化的情况很少。为了量化 CO ₂升高下的光合驯化，粳稻品种“南京 9108”在两种 CO ₂水平下生长- 环境 CO ₂ (a[CO ₂ ]) 和 a[CO ₂ ] +200 μmol mol ^-1 (e[ CO ₂]) 使用开顶室设施。我们基于生化 C3 光合作用模型，在拔节、开花和灌浆阶段测量了Rubisco ( C _c )的净光合速率 ( A _n ) 对 CO ₂的响应。在相同CO ₂浓度下的测量表明，在三个发育阶段，e[CO ₂ ]下的A _n显着低于a[CO ₂ ]下的A _n，表明发生了光合作用的驯化。光合驯化与g _m、g _s和V _cmax的降低_有关，并且g _m主要限制光合作用。的贡献克_米，克_小号和V _CAMX限制光合适应平均65％，25％和总压下的10％甲_Ñ。我们的研究结果表明g _m是光合驯化的主要驱动力，并突出了g _m在 e[CO ₂ ] 下在水稻中的作用。