QTL Mapping for Fiber Quality Based on Introgression Lines Population from G. hirsutum × G. tomentosum

As one of the most widely cultivated cotton species in China, upland has moderate fiber quality and wide applicability, but its genetic basis is relatively narrow. To expand diversity improve quality, this study an introgression population (BC5S5) containing 107 lines was constructed by using G. hirsutum acc. 4105 as recurrent parent tomentosum donor parent. Using specific-locus amplified fragment sequencing (SLAF-seq) strategy, 3157 high-throughput single nucleotide polymorphism (SNP) markers were obtained. Linkage analysis showed that a total ninety-one QTLs related to traits detected three environments, phenotypic variance explained (PVE) rates 4.53–20.92%. Forty-six QTL (50.55%) synergistic genes derived from tomentosum. Among them, qFS-A02-1 qSCI-A02-1 stably with PVE 9.8–16.71% 14.78–20.92%, respectively. Within candidate interval, Ghir_A02G012730, Ghir_A02G012790 Ghir_A02G012830 found be possibly involved cellulose cell wall biosynthesis, high expression during development, 20 DPA 25 DPA, which suggested these may regulation strength traits, their functions need further validation determine regulatory mechanism. Our research lays foundation basic breeding cotton.