GSE125891
Development of high-density genetic map by transcriptome sequencing
Ramie is an important industrial fiber crop, and the fiber yield and its related traits are the most valuable traits in ramie production. However, the genetic basis for these traits is still poorly understood. Herein, a high-density genetic map with 1085 markers spanning 2,118.8 cM was constructed using a population derived from two parents, cultivated ramie Zhongsizhu 1 (ZSZ1) and its wild progenitor B. nivea var. tenacissima (BNT). The fiber yield (FY) and its four related traits—stem diameter (SD) and length (SL), stem bark weight (BW) and thickness (BT)—were performed for quantitative trait locus (QTL) analysis, resulting in eight, six, six, three, and ten QTLs for SD, SL, BW, BD and FY traits, respectively. These 33 QTLs were mapped into 11 genomic regions, thus forming 11 QTL clusters; there were 11 QTLs identified their beneficial alleles from the wild species BNT. Interestingly, all QTLs in Cluster 8 and Cluster 10 displayed overdominance, indicating that these two regions were likely heterotic loci. In addition, there were five fiber yield-related genes identified to undergo positive selection in previous study, and they were found to locate into the genomic region near to the QTLs of this study. The genetic dissection for FY and its related traits improved our understanding to the genetic basis of these traits, as well to their domestication in ramie. The identification of many QTLs and the discovery of beneficial alleles from wild species provided a basis for the improvement of yield traits in ramie breeding. Overall design: The clean reads from the transcriptome of 111 F2 families and two parents were aligned to the ramie genome, then to identify SNPs and develop genetic map.