Figure 5. Structure activity analysis of PMP-related compounds.

(a) Chemical structures of compounds analyzed. (b) Relative susceptibility of Arabidopsis against HpaNoco2. Two-week-old seedlings were sprayed with 10 μM or 25 μM of the indicated compounds or their respective mock controls (1% DMSO or 2.5% DMSO respectively) 24 h prior to HpaNoco2 (3 × 10⁴ spores mL⁻¹) spray infection. Hpa spores were counted 7 days post infection. Shown are relative numbers of spores per seedling compared to values obtained with the respective mock-treated controls. Error bars represent the standard error of the mean based on at least 3 independent replicates. Spore numbers that are significantly reduced after synthetic elicitor treatments compared to mock-treatments based on Student’s t-tests (p < 0.05) are marked by asterisks.