File:Ma206.jpg

Figure 6.—Genetic and physical maps of the gw-5 gene on rice chromosome 5. (A) QTL mapping of the qGW-5 locus. (B) Six BAC/PAC contigs around the gw-5 locus. (C) Fine mapping of gw-5 using newly developed SSR markers. The red superscript a indicates that there are 167 recombinants of the total 805 homozygous plants between the gw-5 gene and the marker RM5874. In fact, the 167 recombinants included 113 wide-grain plants with the heterozygous band patterns of wide- and narrow-grain parents and 27 wide-grain plants with the band pattern of the narrow-grain parent. The recombination frequency ¼ (N1 1 N2/2)/N, where N is the total number of wide-grain plants surveyed, N1 is the number of wide-grain plants with the band pattern of the narrow-grain parent, and N2 is the number of wide-grain plants with the heterozygous band patterns. We marked the number of recombinants between RM5874 and the gw-5 gene as 167 to directly calculate the recombination frequency, [(27 3 2 1 113 ¼ 167)/(805 3 2)] 3 100 (cM). The other numbers marked in the row (no. of recombinants) were also calculated on the basis of this approach.