Table 2 Effects of N regimes on leaf photosynthesis in Panax notoginseng

g_s (mol CO₂ m^− 2·s^− 1)

0.05 ± 0.02 a

0.03 ± 0.02 ab

0.03 ± 0.02 ab

g_m (mol CO₂ m^− 2·s^− 1)

0.09 ± 0.01 c

0.26 ± 0.04 b

0.36 ± 0.02 a

R_d (μmol CO₂ m^− 2·s^− 1)

1.0 ± 0.04 a

0.52 ± 0.02 b

0.57 ± 0.03 b

g_lip (mol CO₂ m^− 2·s^− 1)

2.61 ± 0.08 b

5.52 ± 0.03 a

0.183 ± 0.09 c

C_c (μmol CO₂ m^− 2·s^− 1)

199.53 ± 8.27 b

265.45 ± 7.31ab

291.58 ± 9.15 a

S (mol mol^− 1)

844.15 ± 7.56 b

1057.25 ± 5.41 a

860.16 ± 3.89 b

S*(mol mol^− 1)

739.39 ± 95.61b

983.75 ± 67.32 a

753.41 ± 90.34 b

Rubisco activity (nmol/min/g)

0.643 ± 0.24 c

40.51 ± 5.39 a

22.51 ± 4.89 b

Rubisco content (μg/g⁻¹)

6.931 ± 0.36 c

10.057 ± 0.67 b

70.494 ± 0.32 a

S_c(m² m^− 2)

8.42 ± 1.25 b

12.01 ± 1.65 a

13.15 ± 0.56 a

C_lip (mol CO₂ m^− 2·s^− 1)

0.31 ± 0.06 ab

0.46 ± 0.02 a

0.02 ± 0.01 b

g_i (mol CO₂ m^− 2·s^− 1)

0.13 ± 0.01 b

0.35 ± 0.04 a

0.12 ± 0.05 b

g_m/Rubisco content

12.99 ± 1.23 b

25.81 ± 1.90 a

5.12 ± 0.78 c