Inoculation experiment and qPCR

We detected powdery mildew spores growing on the inoculated, susceptible plant clone leaves on day 14 post inoculation. None of the mock-inoculated or inoculated resistant plant clones showed visible disease symptoms at that time. Gene expression of the marker genes varied considerably in the susceptible inoculated plants and showed elevated levels only at time point 72 h post inoculation (Supplementary Figure 1). This time point was chosen for further analysis.