陆地棉高品质品系纤维品质性状QTL的分子标记及定位

为进一步挖掘利用高品质品系NM03102的优异纤维品质性状的基因,利用陆地棉鲁棉研21作为母本、NM03102为父本构建了F2和F2∶3分离群体。通过7892对SSR引物对亲本进行筛选,获得222对多态性引物,进一步对195个F2群体单株分析得到242个标记位点。其中,182个标记位点连锁构建37个连锁群,共覆盖1661.6 cM,每个连锁群平均包含4.9个标记位点,标记间平均相距9.1 cM,其中35个连锁群被定位到了20条染色体上。利用F2和F2∶3纤维品质数据,通过复合区间作图法,共检测到20个纤维品质性状QTL。其中,1个纤维强度的QTL和1个纤维整齐度的QTL与已有的报道一致,1个纤维强度的QTL和1个麦克隆值的QTL在两世代中稳定存在,这为标记辅助选择奠定了基础。

Molecular Marker of QTL for Fiber Quality Traits in Upland Cotton with Elite Fiber Quality

In order to detect and exploit the QTLs related to superior fiber qualities in upland cotton (Gossypium hirsutum) accession NM 03102，we constructed an F₂ and its corresponding F_2:3 populations by crossing Lumianyan 21 to NM 03102 and employed 7892 simple sequence repeats (SSR) primer pairs to screen the polymorphism between the two parents, 222 polymorphic primer pairs were obtained for genotyping the 195 individual plants of F2 population, and 242 loci were obtained. The linkage test indicated that 182 loci could be mapped to 37 linkage groups, 35 of them could be assigned to 20 chromosomes. The linkage map covered 1661.6 cM , about 37.34% of the whole genome, and the average distance between two loci was 9.1 cM.  20 QTLs were detected based on Composite Interval Mapping (CIM) method, 4 for fiber length, 4 for fiber strength, 5 for fiber micronaire value, 4 for fiber uniformity ration and 3 for fiber elongation, respectively. These QTLs could explain 5.10%~ 28.49% of the corresponding phenotypic variations. QTLs qFS-5-1 and qFU-24-1 were consistent with previous reports in different mapping populations. And 2 QTLs (qFS-5-1 and qFMIC-1-1) could be detected in both F₂ and F_2:3 generations. These stable QTL might be utilized to improve the fiber qualities in the molecular markers assisted selection(MAS) breeding programs.