Supplemental Figure 1. S-haplotype determination of selfed progeny of Pma1. Genomic DNA from selfed progeny of Pma1 were hybridized by a Cyc probe. The hybridizing fragments representing S1- and S4-haplotypes are indicated on the left. I, self-incompatible progeny; C, self-compatible progeny C Supplemental Figure 2. Detection of a centric fragment in Pma1 by meiosis pachytene FISH. Three independent Pma1 lines (A, B and C) were subjected to FISH assay. Biotin-labeled S1SLF-TAC containing AhSLF-S1 (green signal) was used to hybridize the chromosomes of Pma1. A. The centric fragment dissociates completely from the other pachytene chromosomes. B. The centric fragment juxtaposes with the short of chromosome 8 in the same direction. C. The centric fragment dissociates from the other chromosomes. The arrow indicates the length of the centric fragment, and its direction shows the extending direction of the centric fragment from centromere to telomere Supplemental Figure 3. Phylogeny of SLFs from Antirrhinum and Petunia and SFBs from Prunus. The tree topology for Prunus SFBs was obtained from Ikeda et al (2004). The topology for the SLFs from Antirrhinum (AhSLF1, 2, 4 and 5) and Petunia (PiSLF1, 2, 3 and PaSLF17, 19) was obtained using the maximum likelihood analysis implemented in Phylip3.6. Since the tree lengths had no effect on the test result, they are not indicated in the tree.