. 2020 Oct 27;19(3):575–588. doi: 10.1111/pbi.13487

Table 2.

Gas‐exchange and fluorescence parameters of wild‐type (WT) O. sativa and three transgenic lines expressing enzymes of C₄ metabolic pathway

Parameter	WT	Line 1	Line B6	Line 29
R_d, µmol CO₂ m^‐2 s^‐1	1.05 ± 0.05^a	1.11 ± 0.22^a	1.12 ± 0.10^a	1.05 ± 0.04^a
F_V/F_M	0.79 ± 0.01^b	0.78 ± 0.01^b	0.75 ± 0.01^a	0.77 ± 0.01^ab
C_i/C_a	0.74 ± 0.01^a	0.75 ± 0.02^a	0.75 ± 0.02^a	0.76 ± 0.02^a
A, µmol CO₂ m^‐2 s^‐1	29.0 ± 1.2^a	26.5 ± 2.7^a	23.7 ± 2.3^a	22.2 ± 1.9^a
g_{s_H2O}, mol H₂O m^‐2 s^‐1	0.60 ± 0.05^a	0.55 ± 0.05^a	0.48 ± 0.05^a	0.45 ± 0.03^a
V _cmax, µmol CO₂ m^‐2 s^‐1	132 ± 12^a	111 ± 20^a	95 ± 18^a	88 ± 13^a
J, µmol e^‐ m^‐2 s^‐1	144 ± 8^a	140 ± 16^a	121 ± 17^a	119 ± 8^a
J/V _cmax	1.11 ± 0.06^a	1.32 ± 0.11^a	1.32 ± 0.12^a	1.39 ± 0.12^a
TPU, µmol CO₂ m^‐2 s^‐1	10.6 ± 0.4^a	11.0 ± 1.0^a	9.4 ± 1.1^a	9.5 ± 0.6^a

Leaf dark respiration rates (R_d) and the maximum quantum efficiency of Photosystem II (F_V/F_M) were determined after 40‐min dark adaptation. Ratio between intercellular and ambient pCO₂ (C_i/C_a), net CO₂ assimilation rates (A) and stomatal conductance to H₂O (g_{s_H2O}) were determined in steady‐state conditions at 1500 µmol m^‐2 s^‐1 PPFD and C_a = 37 Pa. Maximum carboxylation rate allowed by Rubisco (V _cmax ), rate of photosynthetic electron transport based on NADPH requirement (J), and triose phosphate use (TPU) were determined by fitting the A‐C_i response curves (Figure 4a). Mean ± SE, n = 5 biological replicates for WT, n = 4 otherwise. Statistical analysis was performed using one‐way ANOVA and Tukey’s post hoc test, letters indicate significant differences between the groups (α > 0.05).