Supression of disease symptoms and pathogen population by VOC isolated from <i>Ampelomyces</i> sp.

<p>A. VOC-induced reduction of disease severity caused by <i>Pst</i> DC3000 in Arabidopsis. Severity was scored for each plant as the percentage of total leaf surface with symptoms, from 0 = no symptoms to 100 = most severe with necrotic symptoms. B. Growth of <i>Pst</i> DC3000 (cfu g⁻¹ fresh mass) in leaves. Plants were pretreated with 50 µL of one of the volatile components (0.1 M) for 24 h before inoculation. Methacrylic acid and isobutyl acetate were also tested as volatiles. Controls received only CH₂Cl₂; MeSA and MeJA were used as positive control treatments. Different letters indicate significant differences between treatments according to Bonferroni multiple comparison test (P = 0.05). Data are from representative experiments that were repeated at least 3 times with similar results.