Figure 6.

The effect of inhibition of ethylene biosynthesis or perception on lesion development and H₂O₂ accumulation. Plants were treated before ozone exposure with the ACC synthase inhibitor AVG, ACC oxidase inhibitor CoCl₂, or the ethylene antagonist NBD. Inhibitor-treated plants or untreated controls were then exposed to 250 nL L⁻¹ ozone for 5 h. A, One-half of the leaves were harvested 7 h after the beginning of the exposure and were stained for H₂O₂ production with DAB. B, Cell death (indicated as the percentage lesion of the leaf area) measured after 24 h. Means ± se (n = 3). Columns with the same letter are not significantly (P < 0.05) different according to Tukey's multiple range test.