Article (magazine) published 2008.

he authors have determined in an extensive study that R. mairei is an distinct species, while R. omeiensis is a variety of R. sericea.

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Article (magazine) published 1 Jun 2015.

Background and Aims: The genus Rosa (150–200 species) is widely distributed throughout temperate and sub-tropical habitats from the northern hemisphere to tropical Asia, with only one tropical African species. In order to better understand the evolution of roses, this study examines infrageneric relationships with respect to conventional taxonomy, considers the extent of allopolyploidization and infers macroevolutionary processes that have led to the current distribution of the genus.
Methods: Phylogenetic relationships among 101 species of the genus Rosa were reconstructed using sequences from the plastid psbA-trnH spacer, trnL intron, trnL-F spacer, trnS-G spacer and trnG intron, as well as from nuclear glyceraldehyde 3-phosphate dehydrogenase (GAPDH), which was used to identify putative allopolyploids and infer their possible origins. Chloroplast phylogeny was used to estimate divergence times and reconstruct ancestral areas.
Key Results: Most subgenera and sections defined by traditional taxonomy are not monophyletic. However, several clades are partly consistent with currently recognized sections. Allopolyploidy seems to have played an important role in stabilizing intersectional hybrids. Biogeographic analyses suggest that Asia played a central role as a genetic reservoir in the evolution of the genus Rosa.
Conclusions: The ancestral area reconstruction suggests that despite an early presence on the American continent, most extant American species are the results of a later re-colonization from Asia, probably through the Bering Land Bridge. The results suggest more recent exchanges between Asia and western North America than with eastern North America. The current distribution of roses from the Synstylae lineage in Europe is probably the result of a migration from Asia approx. 30 million years ago, after the closure of the Turgai strait. Directions for a new sectional classification of the genus Rosa are proposed, and the analyses provide an evolutionary framework for future studies on this notoriously difficult genus.

Article (magazine) published 1 Jun 2015.

Rosa sections Chinenses and Synstylae contain approximately 39 wild species mainly distributed in East Asia and are closely related according to previous studies. But the specific relationships within these two sections were still obscure due to limited sampling, low genetic variation of molecular markers, and complex evolutionary histories. In this study, we used four chloroplast (ndhC-trnV, ndhF-rp132, ndhf-trnF and psbJ-petA) and two nuclear (ribosomal ITS and GAPDH) markers with an extensive geographic and taxonomic sampling to explore their evolutionary history. Our phylogenetic analyses suggested that Rosa sections Chinenses and Synstylae defined in traditional taxonomic system are not monophyletic and close to sections Caninae and Gallicanae. Additionally, our results showed incongruence between chloroplast and nuclear markers, and the patterns of incongruence might be due to ancient hybridization (genetic introgression). One putative hybrid species and three samples identified as interspecific hybrids are further discussed in terms of topological incongruence, biological characters and distribution patterns.