Allelic markers mys2 and mys7 inserted in segment N (A), and mys1 and mys8 inserted in segment S (B) were probed with specific green or red oligonucleotide probes. The sequence of each probe and its associated fluorochrome are provided in Supplementary file 1: Table S2. Red and green arrows point at cells where solely the red or the green fluorescence is detected. Yellow arrows point at cells where both fluorescences are detected. Horizontal bars = 10 microns. Nuclei are DAPI-stained in blue. Below images, the table indicates (from left to right): (i) the code number of the petioles analyzed, (ii) the relative frequency of the alleles estimated by qPCR within each petiole as described in the Materials and methods section, (iii) the number of cells where solely one of the alleles could be detected, (iv) the number of cells where solely the other allele could be detected, and (v) the number of cells where the two alleles were detected together. Petiole N°49, 50, 51 and 52 were analyzed independently. Cross sections from petioles 44, 45 and 46, and from petioles 47 and 48 were pooled before both FISH and qPCR analyses.