Abstract:

In order to establish theoretical basis on the molecular marker assisted selection for upland cotton, two F2 populations and their corresponding F2:3 family lines were constructed, which included common male parent with high fiber quality, ‘Xinluzao24’, one of female parent with commercial transgenic variety, ‘Lumian28’, and the other with high-yield traits, ‘Jimian516’. 7638 pairs of SSR primer were used to screen the polymorphism between ‘Lumianyan28’ and ‘Xinluzao24’, finally 225 pairs of polymorphic primer were obtained for genotyping its F2 population, which produced 238 polymorphic loci. A genetic linkage map with 185 loci was constructed, which comprised of 44 linkage groups covering 1509.38 cM with an average distance of 8.16 cM between the two neighbor markers, and approximately 33.91% of the cotton genome. 40 linkage groups were assigned to the corresponding chromosome. Three QTLs for lint percentage and five for seed index were identified with Composite Interval Mapping (CIM) method in the population related to ‘Lumianyan28’ and ‘Xinluzao24’. According to the QTL mapping results, 14 pairs of SSR primer were selected to screen the polymorphism between ‘Jimian516’ and ‘Xinluzao24’ and its F2 population, so two linkage groups with six loci were constructed. One QTL for lint percentage and one for seed index were detected in the two genetic populations. These stable QTLs might be useful in the molecular marker assisted selection (MAS) breeding programs.