Photosynthetic characterization of lines M82, 4‐1, 10‐2 and 11‐3 under well‐watered (WW) and water deficit (WD) conditions in the field. Net photosynthetic rate (A
N), daily carbon fixation rate (C
24h), stomatal conductance (g
s), mesophyll conductance (g
m), total leaf conductannce (g
tot), maximum velocity of Rubisco carboxylation (V
cmax) and intrinsic water use efficiency (WUEi) are shown. Values are means ± standard error of four replicates per line and treatment. Different letters denote statistically significant differences by Tukey analysis (P < 0.05) within each treatment between lines, and asteriks denote statistically significant differences (P < 0.05) between treatments for each line