Exploration of Candidate Genes for Fiber Length in Gossypium mustelinum Based on BSA-seq

Abstract

Fiber length is one of the important characteristics of cotton fiber quality. It is of great significance to explore fiber length genes for breeding of cotton varieties with elite fiber quality. In the first phase of the study, 15 quantitative trait loci(QTLs) of fiber length were mapped based on a set of Gossypium mustelinum introgression lines,and an introgression line IL9 with elite fiber quality was selected by molecular marker-assisted breeding. A large F2 population was constructed by crossing of IL9 with the recurrent Upland cotton parent PD94042. Four DNA pools,namely DNA pools with the longest fiber length, the shortest fiber length, and the two parents, were subjected to nextgeneration sequencing-based bulked-segregant analysis(BSA-seq). Totally 34 potential candidate genes controlling fiber length were located in three regions on Chr.7, Chr.10, and Chr.18. By comparing the results of QTL mapping and BSA-seq, three candidate genes, namely Gh＿D13 G1294, Gh＿D13 G1295, and Gh＿D13 G1296 were obtained by functional annotation. These genes may play important roles in the improvement of fiber length in Upland cotton.

Keywords

• cotton
• fiber length
• molecular breeding
• bsa-seq
• candidate genes