Figure 5.

Photosynthetic parameters of two leaf cohorts grown in current (62 nL L⁻¹ 8-h daily average; white symbol) or elevated (approximately 1.2×; gray symbol) [O₃] over the growing season. The first cohort was initiated in the vegetative phase of growth (V5), the second during flowering (R4) and persisted to late pod filling (R7). Parameters are A_sat (A), V_c,max (B), J_max (C), V_c,max/J_max (D), and l (E). Each point is the mean (n = 4), and the error bars are ± the se of the difference in least square means. Significant linear contrasts over the last 3 or 4 d are noted with a starred bracket. Values of 0 indicate the absence of leaves at that time point. Vegetative (black), flowering (white), and pod-filling (cross-hatched) developmental stages are represented by the horizontal bar.