Fig. 4

Pathogen resistance of Arabidopsis plants pretreated with selected bacteria. RS1P-1–, RS1R-6–, RS2P-3–, RS2P-4–, RS3R-1–, or mock (only medium)–treated Arabidopsis seedlings were cultivated for 7 days, and the plants were then challenged with P. syringae pv. tomato DC3000 or P. carotovorum subsp. carotovorum NBRC 14082 and cultivated for an additional 4 days. (a), representative photographs. (b), proliferation of strain DC3000. After plating extracts of surface-sterilized aerial tissues of plants on medium, the number of colonies of strain DC3000 that formed on the plate was determined. (c), severity of disease caused by strain NBRC 14082. Disease severity is indicated as a percentage calculated by dividing the number of damaged leaves by the number of all leaves. Average values ± SE from three independent experiments are presented. Asterisks indicate a significant difference from the mock control based on Student’s t-test (*, P < 0.05)