A seedling flood-inoculation assay for the analysis of Pseudomonas syringae pv. tomato DC3000 ( Pst DC3000) interactions with Arabidopsis. A. Disease phenotype of Arabidopsis seedlings flood-inoculated with a bacterial suspension of Pst DC3000 containing 0.025% Silwet L-77 at a concentration of 5 × 106 CFU/ml. Photograph was taken 3 dpi. Mock-inoculated seedlings were flood-inoculated with sterile distilled H2O containing 0.025% Silwet L-77. B. Bacterial populations of Pst DC3000 in Arabidopsis. Bacterial populations were quantified at 0, 1, 2, 3 and 4 dpi. Vertical bars indicate the standard errors for three independent experiments.