Fig. 4. Exposing plants twice to MeSA emission induces systemic resistance against a necrotrophic pathogen.

Representative photographs of plants taken at 24 h after challenge with 10⁸ cfu/ml Pectobacterium carotovorum subsp. carotovorum (Pcc) (A). Number of symptomatic leaves per plant measured at 24 h (B). Bars represent the mean ± SE (sample size, n = 16 replications per treatment). Different letters indicate significant differences between treatments (P = 0.05 according to least significant difference). The experiment was repeated three times with similar results.