Figure 2.

Association between chromosomal inversion and flat fruit shape in peach. a, a 1.7‐Mb inversion (grey colour) is located downstream of two SSRs, UDP98‐412 and MA040a, in the S locus co‐segregating with the fruit shape trait (left). Genes surrounding breakpoints are highlighted in different colours (right). H1 and H2 represent wild haplotype without inversion and a mutant haplotype with inversion, respectively. The H2 haplotype contained an ACA deletion and a GA insertion in the proximal and distal breakpoints, respectively. PB and DB represent proximal and distal breakpoints, respectively, and they are highlighted in a square box. P1, P2, and P3 represent PCR fragments amplified with primer pairs of P1F/P1R, P2F/P2R, and P3F/P3R, respectively, with P1 corresponding to the H1 haplotype, while P2 and P3 corresponding to the H2 haplotype. b, Genotyping of chromosomal inversions of progenies derived from ‘Shahong’ (round) × ‘Yanpan’ (flat) (top) and ‘Shennongpan’ (flat) × ‘Yanpan’ (flat) (bottom), respectively. Progenies with round‐ or flat‐shaped fruits harbour homozygous H1H1 and heterozygous H1H2 haplotypes, respectively, while progenies harbouring homozygous H2H2 haplotype bear no fruits due to incidence of abortion during early stages of fruit development.