Zahirul Talukder, Li Gong, Brent Hulke, Venkatramana Pegadaraju, Qijian Song, Quentin Schultz, Lili Qi
Abstract: A high-resolution genetic map of sunflower was constructed by integrating SNP data from three F2 mapping populations (HA 89/ RHA 464, B-line/ RHA 464, and CR 29/ RHA 468). The consensus map spanned a total length of 1443.84 cM, and consisted of 5,019 SNP markers derived from RAD tag sequencing and 118 publicly available SSR markers distributed in 17 linkage groups, corresponding to the haploid chromosome number of sunflower. The maximum interval between markers in the consensus map is 12.37 cM and the average distance is 0.28 cM between adjacent markers. Despite a few short-distance inversions in marker order, the consensus map showed high levels of collinearity with individual maps with an average Spearman’s rank correlation coefficient value of 0.972 across the genome. The order of the SSR markers was also in agreement with the order of the individual maps and with previously published sunflower maps. Three individual and consensus maps revealed the uneven distribution of markers across the genome. Additionally, we performed fine mapping and marker validation of the rust resistance gene R12, providing closely linked SNP markers for marker-assisted selection of this gene in sunflower breeding programs. This high resolution consensus map will serve as a valuable tool to the sunflower community for studying marker-trait association of important agronomic traits, marker assisted breeding, map-based gene cloning, and comparative mapping.
Located in Sunflower and Plant Biology Research. To view article click here.