Figure 4.

Gas diffusional and biochemical limitations of CO₂ assimilation rate after changing from darkness to high light in Arabidopsis and tobacco. The limitations to CO₂ assimilation rate (A) imposed by stomatal conductance (L_gs; dark), mesophyll conductance (L_gm; pale) and biochemical processes were evaluated in (A) Arabidopsis (blue) and (B) tobacco (red), respectively, with the dataset shown in Figure 3. Biochemical limitations assumed either RuBP-carboxylation (upper panels, L_Vcmax) or RuBP-regeneration (bottom panels, L_J) limiting conditions. The vertical bars on each symbol indicate the standard error with 6–8 replicate leaves for Arabidopsis and 3–6 leaves for tobacco. Grey boxes in each figure represent the initial period of darkness. The numbers (0, 1,000, and 1,500) in the grey and white boxes at the top of (A) and (B) indicate the light intensity.