Fine-mapping and candidate gene analysis of qFS-Chr. D02, a QTL for fibre strength introgressed from a semi-wild cotton into Gossypium hirsutum. (August 2020)

• Record Type: Journal Article
• Authors: Feng, Liuchun; Zhou, Chenhui; Su, Qiao; Xu, Min; Yue, Haoran; Zhang, Shuwen; Zhou, Baoliang
• Is Part Of: Plant science. Volume 297(2020)
• Publication Date: 2020-08
• Subjects: Fine mapping -- Fibre strength (FS) -- Gossypium hirsutum -- Introgression line (IL) -- Quantitative trait loci (QTLs) -- qRT-PCR; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2020.110524
• Languages: English
• ISSNs: 0168-9452

Abstract

Highlights: A fibre strength QTL, qFS-Chr. D02, was fine-mapped to a 550.66 kb region between two markers, INTR1027 and JESPR-231. qRT-PCR and SNP analyses revealed GH_D02G2269 and GH_D02G2289 were the most likely candidates for qFS-Chr. D02. The results will provide new information for fibre quality improvement and for uncovering its genetic basis in cotton. Abstract: Fibre strength (FS) is an important quality attribute in the modern textile industry, which is genetically controlled by quantitative trait loci (QTLs). Fine-mapping stable QTLs for FS to identify candidate genes would be valuable for uncovering the genetic basis of fibre quality traits in cotton. Here, a single segment introgression line, IL-D2−2, from the cross of (TM-1×TX-1046) reported in our previous studies, was found to have significantly improved FS compared with the recurrent parent TM-1. To fine-map the QTLs of the FS, we further crossed IL-D2−2 with its recurrent parent TM-1 to produce F2 and F2:3 populations. QTL analysis and substitution mapping showed qFS-Chr. D02 was anchored into a 550.66 kb-interval between two markers, INTR1027 and JESPR-231. This interval contained 67 genes, among which 27 genes related to cell-wall synthesis were selected to conduct qRT-PCR. The results revealed seven genes were expressed significantly differently during the fibre secondary-wall-thickening stage (10–25 days post-anthesis), three being upregulated and four downregulated in IL-D2−2. Both GH_D02G2269 (UDP-glucosyl transferase 84B1) and GH_D02G2289 (unknown function (DUF869)) with nonsynonymous SNPs in IL-D2−2 had significantly downregulated expression, suggesting they were candidates for qFS-Chr. D02. This research provides information about marker-assisted selection for cotton fibre strength improvement.