. 2006 Feb;140(2):779–790. doi: 10.1104/pp.105.073957

Table II.

A (μmol m⁻² s⁻¹), PEPc activity (μmol m⁻² s⁻¹), PPDK activity (μmol m⁻² s⁻¹), Rubisco activity (μmol m⁻² s⁻¹), g_s (mol m⁻² s⁻¹), transpiration (T; mmol m⁻² s⁻¹), c_i (μmol mol⁻¹), ratio of intercellular to atmospheric CO₂ (c_i/c_a), TNC (mmol m⁻²), total protein content (g m⁻²), RWC (%), total water potential (ψ; MPa), N (%) content, and SLA (mm² mg⁻¹) of the youngest fully expanded leaf of maize grown under ambient (370 μmol mol⁻¹) and elevated [CO₂] (550 μmol mol⁻¹) at noon on five dates in 2004 at SoyFACE, Urbana, IL

There was no effect of CO₂ on A (P = 0.81), PEPc activity (P = 0.26), PPDK activity (P = 0.76), Rubisco activity (P = 0.59), c_i/c_a (P = 0.52), TNC (P = 0.25), protein (P = 0.80), RWC (P = 0.60), total ψ (P = 0.86), N (P = 0.21), and SLA (P = 0.48). Asterisk (*), There was a significant CO₂ effect on g_s (P = 0.037), T (P = 0.049), and c_i (P = 0.05).

Parameter	DOY 173		DOY 190		DOY 201		DOY 215		DOY 229
Parameter	[CO₂] 370	[CO₂] 550	[CO₂] 370	[CO₂] 550	[CO₂] 370	[CO₂] 550	[CO₂] 370	[CO₂] 550	[CO₂] 370	[CO₂] 550
A	14.3 ± 2.8	15.0 ± 2.8	29.4 ± 2.8	30.6 ± 2.8	42.4 ± 2.8	42.9 ± 2.8	38.4 ± 2.8	38.8 ± 2.8	26.4 ± 2.8	25.1 ± 2.8
PEPc	222 ± 39	213 ± 18	259 ± 32	248 ± 13	283 ± 19	243 ± 27	230 ± 12	222 ± 18	152 ± 19	174 ± 19
PPDK	32.5 ± 1.7	32.4 ± 5.0	33.0 ± 2.0	34.5 ± 3.3	39.1 ± 2.7	37.9 ± 1.1	25.0 ± 3.0	27.6 ± 2.2	37.6 ± 1.9	32.8 ± 2.6
Rubisco	21.1 ± 3.1	17.9 ± 1.8	17.7 ± 3.1	19.2 ± 2.9	22.4 ± 2.3	18.9 ± 1.2	18.0 ± 2.2	19.6 ± 1.8	13.2 ± 1.0	12.9 ± 1.0
g_s*	0.15 ± 0.04	0.08 ± 0.04	0.27 ± 0.04	0.18 ± 0.04	0.29 ± 0.04	0.18 ± 0.04	0.36 ± 0.04	0.31 ± 0.04	0.17 ± 0.04	0.07 ± 0.04
T*	1.6 ± 0.6	0.9 ± 0.6	2.9 ± 0.6	2.2 ± 0.6	5.7 ± 0.6	3.9 ± 0.6	4.8 ± 0.6	3.6 ± 0.6	4.7 ± 0.6	1.9 ± 0.6
c_i*	167 ± 31	226 ± 31	187 ± 31	241 ± 31	118 ± 31	141 ± 31	187 ± 31	292 ± 31	126 ± 31	154 ± 31
c_i/c_a	0.45 ± 0.13	0.41 ± 0.13	0.49 ± 0.13	0.43 ± 0.13	0.31 ± 0.13	0.25 ± 0.13	0.50 ± 0.13	0.52 ± 0.13	0.33 ± 0.13	0.19 ± 0.13
TNC	14.2 ± 1.1	13.0 ± 0.9	11.4 ± 1.1	11.9 ± 0.9	18.3 ± 0.9	18.1 ± 0.9	20.1 ± 0.9	17.7 ± 0.9	20.4 ± 0.9	18.4 ± 1.1
Protein	10 ± 1	10 ± 1	11 ± 1	12 ± 2	12 ± 1	12 ± 1	13 ± 1	12 ± 1	11 ± 1	11 ± 1
RWC	93.5 ± 0.7	90.8 ± 2.0	93.7 ± 0.5	92.6 ± 1.4	94.1 ± 0.8	94.6 ± 1.0	90.2 ± 2.4	91.2 ± 0.9	94.0 ± 1.5	96.4 ± 1.2
Total ψ	−1.0 ± 0.1	−1.0 ± 0.1	−1.5 ± 0.1	−1.4 ± 0.1	−1.5 ± 0.1	−1.7 ± 0.1	−2.1 ± 0.1	−1.9 ± 0.1	−2.1 ± 0.1	−2.1 ± 0.2
N	4.0 ± 0.1	4.0 ± 0.1	3.2 ± 0.2	3.2 ± 0.1	3.5 ± 0.1	3.7 ± 0.1	3.0 ± 0.1	3.0 ± 0.1	2.6 ± 0.1	2.8 ± 0.1
SLA	27 ± 2	30 ± 2	23 ± 1	23 ± 1	18 ± 1	21 ± 1	17 ± 1	19 ± 2	17 ± 1	18 ± 1