Three chloroplast DNA (cpDNA) sequences [the rpl16 intron, the trnL-F, and atpB-rbcL intergenic spacer (IGS)] were employed to study phylogenetic relationships in the genus Rosa. Phylogenetic analyses using these three concatenated sequences were performed using maximum parsimony (MP) and Bayesian inference (BI) methods. Both analyses results suggest that the molecular phylogeny conforms closely to the conventional classification of botanical sections. Morphological similarities between R. sects. Synstylae and Chinenses, and R. sects. Rosa and Carolinae are corroborated on the molecular level in our analyses. Four taxa from R. sect. Pimpinellifoliae are further divided into two small clades, which reflect the morphological characters for these species on a molecular level. Whereas three accessions of R. foetida from R. sect. Pimpinellifoliae form a separate clade. R. ×fortuniana forms a clade with R. laevigata based on its maternal inheritance of cpDNA. R. ×cooperii is hypothesized to be a hybrid with seed parent from R. sects. Synstylae and Chinenses. And R. roxburghii should be classified as a section within the R. subgen. Rosa, rather than being treated as its own subgenus, based on molecular analyses.
Chengyuan Liu, Guoliang Wang, Hui Wang, Tao Xia, Shouzhou Zhang, Qigang Wang and Yanming Fang
Ninghang Wang, Chao Zhang, Sainan Bian, Pengjie Chang, Lingjuan Xuan, Lijie Fan, Qin Yu, Zhigao Liu, Cuihua Gu, Shouzhou Zhang, Yaling Wang and Yamei Shen
Magnolia (Magnoliaceae) is widely cultivated for its beauty; however, despite this, the components of the different flower colors in Magnolia have not been elucidated. In this study, the color parameters of 10 Magnolia petals with different colors were measured by the Royal Horticultural Society Color Chart (RHSCC) and a color reader CR-10. The composition and content of the flavonoids in the petals were analyzed by high-performance liquid chromatography coupled with diode array detection (HPLC-DAD) as well as HPLC with electrospray ionization and mass spectrometry (HPLC-ESI-MS2). All results showed that the 10 petals were divided into four color groups. Regarding the flavonoid composition, four types of anthocyanins, including Cyanidin-glucosyl-rhamnoside (Cy-GR), Cyanidin-glucosyl-rhamnosyl-glucoside (Cy-GRG), Peonidin-glucosyl-rhamnoside (Pn-GR), and Peonidin-glucosyl-rhamnosyl-glucoside (Pn-GRG), were identified, as well as 10 types of flavonols. The flavonols included isorhamnetin, quercetin, kaempferol, and their glycosides, which included rutinoside, rhamnose, and glucoside. Cyanidin and peonidin make Magnolia petals appear red-purple and purple, respectively, and the flavonols perform as evident auxiliary pigments, particularly quercetin. The Magnolia cultivar flower phenotypes sampled in this study differed by changes in their existing flavonoid content rather than by the appearance of new flavonoids. Consequently, this study provides a reference for further revealing the basis of Magnolia flower color and provides clues for color breeding.