利用向日葵重组自交系构建遗传图谱

以向日葵自选系K55为母本、K58为父本杂交组合,通过单粒传得到的187个F_5：6代重组自交系群体为作图材料,联合应用SSR和AFLP标记构建遗传连锁图谱。经过78对SSR引物和48对AFLP引物组合选择性扩增,分别得到341和1119条带,共1460条,分别获得多态性条带184条和393条,共577条多态性条带,占所有条带的39.52%。SSR和AFLP标记各有84个和108个多态性标记偏离孟德尔分离比例(P=0.05),共192个偏分离标记。采用JoinMap4.0软件进行连锁分析,构建了1张总长度为2759.4 cM、包含17个连锁群、连锁495个多态性标记的遗传图谱,其中偏分离标记170个,标记间的平均图距为5.57 cM。每个连锁群上分布有5~72个标记,长68.88~250.17 cM。本图谱为向日葵永久性图谱,为向日葵重要性状QTL定位和基因克隆奠定基础。

Construction of a genetic map of sunflower using a population of re-combinant inbred lines (RILs)

A genetic linkage map of sunflower was constructed by combined applying the SSR and AFLP markers using 187 F_5:6 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.