[Construction of a genetic map of sunflower using a population of recombinant inbred lines (RILs)]

A genetic linkage map of sunflower was constructed by combined applying the SSR and AFLP markers using 187 F5:6 individuals of recombinant inbred lines (RILs) which derived from the cross between Helianthus annuus K55 and Helianthus annuus K58 through single-seed descent (SSD). Using 78 pairs of SSR primers and 48 pairs of AFLP primer, 341 and 1119 bands were amplified, respectively. Among these 1460 bands, 557 bands (39.52%) were polymorphic, including 184 bands by SSR markers and 393 bands by AFLP markers. In the group of these polymorphic bands, 84 bands from SSR markers and 108 bands from AFLP markers showed the genetic distortion (P = 0.05). A total of 192 segregation distortion markers were obtained in this study. By using the JoinMap 4.0 software to do the linkage analysis, a genetic linkage map was established with length of 2759.4 cM, consisted of 17 linkage groups, and comprised of 495 polymorphic molecular markers including 170 segregation distortion markers. The mean marker interval distance is 5.57 cM between markers. In addition, the number of markers in the linkage groups varied from 5 to 72, and the length of linkage groups were from 68.88 cM to 250.17 cM. The genetic map developed in the present study could be used for QTL mapping and gene cloning of sunflower important genes.