S05 - Session P5 - Identification and QTL analysis of flavonoids and carotenoids in tetraploid roses based on an ultra-high-density genetic map

Authors: Bixuan Cheng *, Qixiang Zhang, Chao Yu

Roses are highly valuable within the flower industry. With the continuous exploration of roses, their values appear not only in decorations, but also in the food, medicine and cosmetic markets. The metabolites of anthocyanins, flavonols and carotenoids in rose petals are responsible for the various visible petal colors. Apart from that, they are also essential bioactive compounds that are important for human health. In this study, we performed a QTL analysis on pigment contents to locate major loci that determine the flower color traits. An F 1 population of tetraploid roses segregating for flower color was used to construct an ultra-high-density genetic linkage map using whole-genome resequencing technology to detect genome-wide SNPs. Previously developed SSR and SNP markers were also utilized to increase the marker density. As a result, a total of 9,259 markers were mapped onto seven linkage groups (LGs). The final length of the integrated map was 1285.11cM, with an average distance of 0.14 cM between adjacent markers. The contents of anthocyanins, flavonols and carotenoids of the population were assayed to enable QTL analysis. Across the 33 components, 46 QTLs were detected, explaining 11.85n47.72% of the phenotypic variation. The mapped QTLs were physically clustered and primarily distributed on four linkage groups, namely LG2, LG4, LG6 and LG7. These results improve the basis for flower color marker-assisted breeding of tetraploid roses and guide the development of rose products.