Figure 2.

Variation in (a) CO₂ assimilation rate (A), (b) stomatal conductance (g_s), (c) intercellular CO₂ concentration (C_i), and (d) maximum quantum efficiency of the photosystem II photochemistry (F_v/F_m) in leaves of sage exposed to charcoal-filtered air (open circle) or to 120 ppb of ozone (5 h day⁻¹) for 36 consecutive days (closed circle). Data are shown as mean ± standard deviation. For each parameter, p levels for the effects of ozone, time, and their interaction from a one-way repeated measures ANOVA are shown (***: p ≤ 0.001, **: p ≤ 0.01, *: p ≤ 0.05). According to Tukey’s HSD post hoc test, different letters indicate significant differences among means (p ≤ 0.05).