The analysis of association between genotypic markers and phenotypic traits allows identification of quantitative trait loci (QTLs), which can be applied through marker-assisted selection in breeding programs to improve the quality of crops. However, success in these applications depends primarily on the stability and dominance of the QTL. We previously identified a significant fiber length (FL) QTL on chromosome (Chr.) D11 based on the genome-wide association study (GWAS) of a multi-parent advanced generation inter-cross (MAGIC) population in upland cotton. In this report, we conducted mapping studies with two bi-parental populations to confirm the stability of the FL QTL on Chr. D11 and determine the magnitude of its effect on the fiber length phenotype. One of the F₂ populations was developed from a cross between the longest fiber and the shortest fiber recombinant inbred lines (RILs) of the MAGIC population originally used for GWAS, whereas the second F₂ population was created from a cross between two cotton lines Acala 1517–80 and JJ1145ne, which were not among the eleven MAGIC parental lines. The populations were grown in different environmental conditions. Genetic mapping of these populations confirmed the stability of the FL QTL on Chr. D11. The highest LOD scores of association with fiber length in both populations showed three SNP markers that resided within 360 kb of the QTL region on Chr. D11. Ten genes possessing non synonymous SNPs (nsSNPs) in their protein coding regions were identified in this region. RNAseq analysis detected activity in developing fiber tissue for seven of these candidate genes.

通过对基因型标记和表型性状之间的关联进行分析，可以鉴定出数量性状基因座（QTL），可以通过在育种程序中通过标记辅助选择来提高作物的品质。但是，这些应用程序的成功主要取决于QTL的稳定性和优势。我们先前基于陆地棉的多亲代高级杂交（MAGIC）群体的全基因组关联研究（GWAS），在染色体（Chr。）D11上确定了重要的纤维长度（FL）QTL。在本报告中，我们对两个双亲种群进行了作图研究，以确认FL QTL对Chr的稳定性。并确定其对纤维长度表型的影响大小。F _2之一种群由最初用于GWAS的MAGIC种群的最长纤维和最短纤维重组近交系（RIL）之间的杂交产生，而第二个F ₂种群是由两个棉线Acala 1517-80和JJ1145ne之间的杂交产生的，这两个棉线不在MAGIC的11个亲本线中。种群在不同的环境条件下生长。这些人群的遗传图谱证实了FL QTL在Chr上的稳定性。D11。在这两个种群中，与纤维长度相关的最高LOD得分显示了三个SNP标记，它们位于Chr上QTL区的360 kb之内。D11。在该区域中鉴定了十个在其蛋白质编码区域中具有非同义SNP（nsSNPs）的基因。RNAseq分析检测了其中七个候选基因在纤维组织发育中的活性。