Molecular Evidence for Hybrid Origin and Phenotypic Variation ofRosaSectionChinenses

Rosasect.Chinenses(Rosaceae) is an important parent of modern rose that is widely distributed throughout China and plays an important role in breeding and molecular biological research.R.sect.Chinenseshas variable morphological traits and mixed germplasm. However, the taxonomic status and genetic background of sect.Chinensesvarieties remain unclear. In this study, we collected germplasm resources from sect.Chinensesvarieties with different morphological traits. Simple sequence repeat (SSR) markers, chloroplast markers, and single copy nuclear markers were used to explore the genetic background of these germplasm resources. We described the origin of hybridization of rose germplasm resources by combining different molecular markers. The results showed that the flower and hip traits of different species inR.sect.Chinenseswere significantly different. The SSR analysis showed that the two wild type varieties have different genetic backgrounds. The double petal varieties ofR.sect.Chinensescould be hybrids of two wild type varieties. A phylogenetic analysis showed that the maternal inheritance of sect.Chinensesvarieties had two different origins. To some extent, variation in the morphological traits of double petal species ofR.sect.Chinensesreflects the influence of cultivation process. This study emphasizes that different genetic markers vary in their characteristics. Therefore, analyzing different genetic markers in could provide an insight into highly heterozygous species.