Fine mapping of FOC1 using the DH and F
populations. (a) The genetic map of 18 markers obtained from JoinMap 4.0. (b) Preliminary mapping of FOC1 using the DH population. The FOC1 gene was mapped to an interval of about 382 kb with S3 and A1 as the flanking markers according to the reference sequence of B. oleracea. (c) Fine mapping of FOC1 using the F2 population with 3976 plants. The FOC1 gene was delimited to an interval between V17 and S9, with an estimated length of 84 kb. (d) Ten genes were annotated between markers V17 and S9 based on the reference genome sequence. The genetic structure for each recombinant type is depicted as black rectangles for homozygous susceptible alleles, white for homozygous susceptible alleles and grey for heterozygous alleles, respectively. The relative positions of markers on C06 were determined according to the B. oleracea genome sequence.