Mapping quantitative trait loci for days-to-heading, and culm, panicle and internode lengths in a BC₁F₃ population using an elite rice variety, Koshihikari, as the recurrent parent

An RFLP linkage map was constructed using a BC₁F₃ population, which was developed by backcrossing between an elite Japonica rice variety, Koshihikari, as the recurrent parent and an Indica rice variety, Kasalath, as a donor parent. The map was constructed using data from 187 plants and 116 RFLP markers. Quantitative trait loci (QTL) analyses were carried out for days-to-heading, and culm, panicle, and internode lengths. Four QTLs (p < 0.001) for days-to-heading, six for culm length, and four for panicle length were detected. Seventeen QTLs were detected for the internode length. Chromosomal locations of putative QTLs in this study were compared with those in other studies. Several QTLs for these traits, showing a correlation with phenotypic values, were mapped in the same chromosomal regions. However, the sets and relative effects of QTLs for internode length were different among the corresponding QTLs for culm length. The implications of QTL analysis in the BC₁F₃ generation for rice chromosome introgression breeding are discussed.