Abstract:Fiber quality and lint percentage are the main target trait of cotton breeding improvement. In order to explore the elite genetic resources of fiber quality, a genetic map is constructed and QTLs are detected based on an F2 population of 372 individuals derived from a cross between upland cotton Sealand (Se) (a superior fibre-quality germplasm of Gossypium hirsutum L. with G. barbadense L. introgressions) and upland cotton Lumianyan 37 Hao (L37) (a high-yield G. hirsutum L. cultivar). A total of 9628 primer pairs were used to screen polymorphism between the two parents, and 320 pairs of polymorphic primers were identified. The polymorphic primers accounted for 3.32%. Linkage test (LOD=6.5) indicated that 248 polymorphic loci could be mapped into 26 chromosomes and covered a total genetic distance of 2347.63 cM, which was approximately 52.76% of the cotton genome. The average number of marker loci per chromosome was 9.54, with a mean spanning distance of 9.50 cM. Twenty QTLs for fiber quality traits and lint percentage were identified, including two for fiber upper half length (FL), two for uniformity (FU), five for fiber strength (FS), four for micronaire (FM), four for elongation (FE) and three for lint percentage (LP). These QTLs could explain 3.50%-16.82% of the phenotypic variation. The favorable alleles of 11 QTLs for fiber upper half length, strength and fiber elongation were derived from Se, while the favorable alleles of nine QTLs for micronaire, fiber upper half length, uniformity and lint percentage were derived from L37. A QTL cluster including QTLs for fiber upper half length, strength and micronaire and containing 148 genes was identified on D6 chromosome. Three genes related to fiber development, Gh_D06G0039, Gh_D06G0142 and Gh_D06G0145, were identified by GO enrichment analysis and KEGG enrichment analysis combined with TM-1 transcriptome data. This study laid a foundation for fine mapping QTL of fiber quality and lint percentage of cotton and for identifying related candidate genes.