Figure 7.

Knockdown of ATL1 Enhances Susceptibility to Powdery Mildew and Suppresses edr1-Associated Cell Death.

(A) Quantitative analysis of powdery mildew conidia (asexual spores) on ATL1 amiRNAi transgenic Arabidopsis lines. The indicated Arabidopsis lines were inoculated with powdery mildew and conidium production determined 8 d later. Bars indicate the mean of n ± sd (n = 3). Lowercase letters indicate values that are significantly different (P < 0.01; two-way ANOVA test followed by a Bonferroni post-hoc test).

(B) Trypan blue staining of powdery mildew-infected ATL1 amiRNA lines. The indicated lines were assessed for leaf mesophyll cell death and conidium production at 8 d after infection using trypan blue staining. Only the nontransformed edr1 mutant showed significant patches of cell death. Bars = 100 μm.

(C) Quantification of cell death in powdery mildew infected ATL1 amiRNA lines. The trypan blue-stained area in 30 leaves was measured for each genotype using ImageJ and divided by the total leaf area. Results are provided as means with 10th and 90th percentiles (box) and range (whiskers). Statistical outliers are shown as circles. Lowercase letters indicate values that are significantly different (P < 0.0001; two-way ANOVA followed by a Bonferroni post-hoc test).