Linkage map showing the location of HWA1 and HWA2 on rice chromosome 11. a RFLP framework map of chromosome 11 quoted from Harushima et al. (1998). b Linkage map of HWA1 constructed from the three-way cross population [P.T.B.7 × (T65 × P.T.B.10)] (n = 176). c Linkage map of HWA2 constructed from the three-way cross population [A.D.T.14 × (T65 × P.T.B.7)] (n = 175). Genotypes of RM5349 and RM224 were analyzed for 94 plants in HWA1 mapping and for 96 plants in HWA2 mapping to know if these genes are located between the two markers. *, **, ***, and **** mean that the gene segregation was significantly deviated from the expected ratio (1: 1) at 0.05, 0.01, 0.001, and 0.0001 levels, respectively.