Fig. 6

The old12 auto-immunity phenotype relies on SA. A Callose depositions as visualized by aniline blue staining (light blue fluorescence) of 3rd and 4th leaves of 24 DAS (long-day) plants. Scale bar = 200 µm. B PR gene expression in 27 DAS plants grown on soil under long-day condition. Expression data represents means ± SD from three biological replicates. Expression level for each gene was normalized against ACT2. Asterisks indicate significant difference from WT (Student’s t-test; p ≤ 0.05). C Expression of SA biosynthesis genes in Ler-0 and old12 mutants. Bars represent mean ± SD from three biological replicates. Asterisks indicate significant difference from WT (Student’s t-test; p ≤ 0.05). D Crossing nahG into the old12 mutant background reverts the early-senescence phenotype. An F2 population of nahG x old12 was phenotyped and genotyped to determine the presence of old12 SNPs, and the presence of the nahG gene. In the table, a ´ + ´ indicates the presence of either the wild-type and/or old12 allele, and/or the nahG gene. Early senescence is indicated by a yellow score in the table, a green score indicates no early senescence, whereby a dark green color highlights plants that are homozygous for the old12 mutation and at the same time contain the nahG transgene. Shown are plants grown under long-day conditions at 28 DAS