Molecular phylogenetic evidence for a wide circumscription of a characteristic Irano-Turanian element: Acantholimon (Plumbaginaceae: Limonioideae)

Acantholimon is an important component of the subalpine steppe flora in the Irano-Turanian region and the second largest genus of Plumbaginaceae with c. 200 cushion-forming subshrubby species. Because the genus has been poorly represented in previous phylogenetic studies, questions regarding its monophyly, phylogenetic relationships and infrageneric classification have not been addressed in a solid evolutionary framework. We used sequences from the nuclear ribosomal internal transcribed spacers and the plastid trnY(GUA)–trnT(GGU) intergenic spacer for 197 accessions of Acantholimon and nine putatively closely related Asian genera in Limonioideae. Contrary to previous results, Bayesian, maximum likelihood and maximum parsimony analyses show that Acantholimon is not monophyletic unless its limits are extended to include species currently placed in eight of these Asian genera. As circumscribed, the new Acantholimon s.l. is sister to Goniolimon and includes the following genera: Bamiania, Bukiniczia, Chaetolimon, Cephalorhizum, Dictyolimon, Gladiolimon, Popoviolimon and Vassilczenkoa. Our phylogenetic analyses also challenge the existing classification at the generic and infrageneric levels. A maximum likelihood reconstruction of ancestral states for morphological characters illustrates the possible scenarios by which the cushion architecture combined with linear acuminate leaves, also present in other steppic Irano-Turanian elements, were acquired in this group of Plumbaginaceae. Our study shows the importance of extensive taxon sampling for phylogenetic reconstruction of species-rich lineages. APeer reviewe

Genetic diversity and genetic similarities between Iranian rose species

Wild rose species were collected from different regions of Iran for a rose breeding programme. They included accessions from Rosa persica, R. foetida, R. pimpinellifolia, R. hemisphaerica, R. canina, R. iberica, R. damascena, R. beggeriana, and R. orientalis. Ten microsatellite (simple sequence repeat; SSR) markers were used to analyse the genetic variation among these rose species. The SSR markers amplified alleles in all species, even if they were from different sections within the genus. An unweighted pair group method cluster analysis (UPGMA) based on similarity values revealed five main Groups. The data showed no support for any distinction between R. canina and R. iberica, as all the accessions were placed in one Group, and accessions of these two species were more closely-related to each other within a Province than to accessions of the same species in other Provinces. Accessions of sect. Pimpinellifoliae were combined with plants from sect. Rosa and Cinnamomeae in two different Groups. Genetically, R. persica clustered distinctly from all others, with few alleles shared with the other taxa. We discuss the use of SSR markers for phylogenetic analysis when these markers are amplified in all species of a genu