Fig. 3

Changes in cell wall appositions and biosynthetic gene expression in response to A. brassicicola infection. A Leaves from control, infected, MS-treated and MS-infected plants were stained with aniline blue (3-dpi). A higher intensity of callose deposition fluoresces bright blue (indicated by arrow). The mean callose fluorescence intensity quantitatively determined in inoculated leaves. The image is a representation of several leaves (n = 15). The relative gene expression of GSL6 was quantified 5 dpi. B-C The relative expression of PRX71 and PAD3 involved in the synthesis of lignin and the phytoalexin camalexin, respectively 5 dpi. D Leaves from control and MS -infected plants stained with 3,3′-Diaminobenzidine stain (36 hpi) that forms brown precipitation to indicate reactive oxygen species (ROS) accumulation. The relative expression of ROS marker genes (GST1 and RBOHD), was determined 5 dpi. The expression levels of all genes were normalized to the β-ACTIN housekeeping gene (n = 4 biological reps) and are representative of at least two independent experiments. Error bars show standard error. Letters are statistical differences using ANOVA with the Bonferroni test (p < 0.05). Scale bars = A, 50 μm; C, 1 cm