Figure 5.

Transcript abundance of RbohD, PRX33 and PRX34 genes at three leaf levels. Gene expression was analysed in leaves representing three consecutive physiological states (upper, middle and lower). Five‐ to six‐week‐old wild‐type Arabidopsis plants (whole rosettes) were spray inoculated with Alternaria brassicicola conidial suspension at a concentration of 5 × 10⁵ conidia/mL distilled water. Mock‐inoculated and A. brassicicola‐infected [24 h after inoculation (hai)] plants were assayed. Relative gene expression was calculated using the comparative 2^–ΔΔCT method and At4g26410 as a reference gene. The results show the average of two experiments, each comprising three biological samples (each sample composed of a pool of the corresponding leaves of three Arabidopsis rosettes), analysed in three technical replicates. True leaves growing on one plant were divided evenly into three age groups: lower leaves (typically in positions 1–4), middle leaves (in positions 5–8) and upper leaves (in positions 9–12). Different letters represent relative transcript values significantly different at P < 0.05. Statistical analysis was performed using one‐way analysis of variance (ANOVA) and Tukey’s post hoc test.