Figure 3.

NbADR1, NbPAD4, and NbEDS1 mediate flg22-induced stomatal immunity. A, B) Images of stomata A) and stomatal apertures B) in leaves of Nicotiana benthamiana TRV-GUS and TRV-NbFLS2/NbBAK1 after 1 h of flood treatment with mock (ddH₂O) or 100 nM flg22. Data are means ± Sd; n = 50 stomata. Letters indicate significant differences by 1-way ANOVA analysis (Tukey's post hoc test, P < 0.05). Scale bars represent 5 μm. The experiments were repeated 3 times with similar results. C, D) Disease symptoms C) and bacterial populations D) in leaves of N. benthamiana TRV-GUS and TRV-NbFLS2/NbBAK1 at 7 d C), or at 0 and 4 d D) postspray inoculation with Pseudomonas syringae pv. tomato (Pst) DC3000 ΔHopQ1 (OD₆₀₀ = 0.4). Data are means (±Sd) of 4 biological replicates from independent plants. Letters indicate significant differences by 1-way ANOVA analysis (Tukey's post hoc test, P < 0.05). The experiments were repeated 3 times with similar results. CFU stands for colony-forming unit. Scale bars represent 1 cm. E, F) Images of stomata E) and stomatal apertures F) in leaves of N. benthamiana wild-type (WT) and the indicated mutants after 1 h of flood treatment with mock (ddH₂O) or 100 nM flg22. Data are means ± Sd; n = 50 stomata. Letters indicate significant differences by 1-way ANOVA analysis (Tukey's post hoc test, P < 0.05). Scale bars represent 5 μm. The experiments were repeated 3 times with similar results. G, H) Bacterial pathogen entry assay in leaves of N. benthamiana WT and the indicated mutants. The leaves were pretreated with 100 nM flg22 for 1 h before bacteria treatment. The leaves were photographed and quantified by a CCD imaging system after 1 h of P. syringae pv. maculicola ES4326-lux flood treatment (OD₆₀₀ = 0.5). Data are means (±Sd) of 3 biological replicates from independent plants. Letters indicate significant differences by 1-way ANOVA analysis (Tukey's post hoc test, P < 0.05). Scale bars represent 1 cm. cps, counts per second.