Figure 1.

PMR4 overexpression confers complete powdery mildew resistance in Arabidopsis. Three-week-old 35S::PMR4-GFP, pmr4, and wild-type plants were inoculated with the virulent powdery mildew Gc. A, Infection phenotypes 7 dpi in comparison with uninfected control plants. B, Biomass determination (excluding roots) of control and infected Arabidopsis lines at 10 dpi. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001 by Tukey’s test. Error bars represent se, and n ≥ 25 independent plants. A repeat experiment gave similar results. C, Localization of callose deposition by aniline blue staining (blue fluorescence in top two rows) and visualization of fungal growth by trypan blue staining (bottom row) on the rosette leaf surface at 7 dpi. agt, Appressorial germ tube; c, conidium; cp, conidiophores; h, hyphae. Bars = 50 µm.