FIGURE 4.

Intensity and transgenerational stability of Plectosphaerella cucumerina-mediated t-IR in matched environments. Parental plants had been exposed to different disease severities by necrotrophic Plectosphaerella cucumerina (Pc; Mock, Pc-I, Pc-II, and Pc-III). F1 and F2 plants were analyzed for resistance against the same pathogen. Lesion diameters were determined in four leaves/plant at 15 dpi and the average lesion diameter per plant was used as statistical unit of replication. Boxplots show the interquartile range (IQR; box) ± 1.5xIQR (whiskers), including median (horizontal line) and replication units (dots). (A) t-IR against Pc in F1 progeny. Data represent lesion diameters (mm) of plants within F1 populations from similarly treated parents (n = 40). Different letters indicate statistically significant differences (Welch ANOVA + Games-Howell test, α = 0.05). Data for individual F1 populations are shown in Supplementary Figure 3A. (B) t-IR against Pc in F2 progeny after a stress-free F1 generation. Data represent lesion diameters of plants within F2 populations that share a common parental ancestor (n = 20). Different letters indicate statistically significant differences (ANOVA + Tukey’s post hoc test; α = 0.05). Data for individual F2 populations are shown in Supplementary Figure 3B.