Phylogenetic studies in Gnaphalieae (Compositae): The genera Phagnalon Cass. and Aliella Qaiser & Lack

130 p., tablas, mapas, fot. -- Se corresponde con el capítulo 7 del libro Recent Advances in Pharmaceutical Sciences IIIThe precise generic delimitation of Aliella and Phagnalon, and their closest relatives within the Gnaphalieae are discussed in this review. Among the main results obtained, we have found that the genera Aliella and Phagnalon are nested within the “Relhania clade” and Anisothrix, Athrixia and Pentatrichia are their closest relatives. Macowania is also part of the “Relhania clade”, whereas the subtribal affinities of Philyrophyllum lie within the “crown radiation clade”. The monophyly of Aliella and Phagnalon is not supported statistically. In addition, Aliella appears to be paraphylethic in most of the analyses performed. The resulting phylogeny suggests an African origin for the ancestor of Aliella and Phagnalon and identifies three main clades within Phagnalon that constitute the following natural groups on a geographic basis: (1) the Irano-Turanian clade; (2) the Mediterranean-Macaronesian clade; and (3) the Yemen-Ethiopian clade. Some endemics to Yemen and Ethiopia appeared merged in the Mediterranean-Macaronesian clade, providing new evidence of the phytogeographical links between Macaronesia, Eastern Africa and Southern Arabia. Incongruities between the chloroplast and nuclear molecular data and the lack of resolution in some clades may indicate that hybridization could have played an important role in the evolution and diversification of both Phagnalon and Aliella.This work has been partly financed by the Spanish government (REN2002-04634-C05-01, CGL2004-04563-C02-01/BOS) and the Catalan government (“Ajuts a grups de recerca consolidats” 2009/SGR/00439).Peer reviewe

Phylogeography of western Mediterranean Cymbalaria (Plantaginaceae) reveals two independent long-distance dispersals and entails new taxonomic circumscriptions

The Balearic Islands, Corsica and Sardinia (BCS) constitute biodiversity hotspots in the western Mediterranean Basin. Oligocene connections and long distance dispersal events have been suggested to cause presence of BCS shared endemic species. One of them is Cymbalaria aequitriloba, which, together with three additional species, constitute a polyploid clade endemic to BCS. Combining amplified fragment length polymorphism (AFLP) fingerprinting, plastid DNA sequences and morphometrics, we inferred the phylogeography of the group and evaluated the species' current taxonomic circumscriptions. Based on morphometric and AFLP data we propose a new circumscription for C. fragilis to additionally comprise a group of populations with intermediate morphological characters previously included in C. aequitriloba. Consequently, we suggest to change the IUCN category of C. fragilis from critically endangered (CR) to near threatened (NT). Both morphology and AFLP data support the current taxonomy of the single island endemics C. hepaticifolia and C. muelleri. The four species had a common origin in Corsica-Sardinia, and two long-distance dispersal events to the Balearic Islands were inferred. Finally, plastid DNA data suggest that interspecific gene flow took place where two species co-occur

Amplificación cruzada de microsatélites en el género Centaurea (Compositae).

11p. Fotog. en color. Tablas.[EN] Microsatellites are widely used for population genetic studies although the development of these species-specific markers is costly and time-consuming. One strategy for saving time and money is the use of markers developed for one species (source species) in a different species (target species). This is known as cross-amplification. In the present work, two sets of microsatellites are used to test their transferability to six narrow endemic Centaurea species: i) 16 nuclear loci previously published for three congeneric species and ii) 10 universal chloroplast markers designed from Nicotiana tabacum sequences. Seventeen of the 26 markers tested were transferable and 14 of them were also polymorphic and therefore useful for future works. Nuclear markers were more variable and thus more informative than chloroplast markers. Interspecific amplification performed better for the nuclear loci developed for different Centaurea species than for the universal chloroplast markers developed for Nicotiana tabacum. Likewise, transferability was more successful for the species from sect. Phalolepis than for sect. Lepteranthus. Therefore, our results support the idea that the success of the cross-amplification is influenced by the evolutionary distance between the target and the source species.[ES] Los microsatélites se usan habitualmente en estudios de genética de poblaciones aunque su desarrollo es un proceso caro y largo dada su elevada especificidad. Una estrategia que permite ahorrar tiempo y dinero es la llamada amplificación cruzada que consiste en amplificar el DNA de una especie determinada (especie objetivo) usando marcadores que han sido diseñados para una especie diferente (especie fuente). En este trabajo se ha realizado un ensayo sobre amplificación cruzada usando seis endemismos del género Centaurea y dos conjuntos de microsatélites: i) 16 marcadores nucleares desarrollados para tres especies congenéricas y ii) 10 marcadores cloroplásticos universales diseñados para Nicotiana tabacum. Diecisiete de los 26 marcadores evaluados resultaron transferibles, de los cuales 14 fueron polimórficos siendo así útiles para futuros trabajos. Las regiones nucleares se mostraron más variables y por lo tanto más informativas que las cloroplásticas. La amplificación cruzada funcionó mejor para los marcadores nucleares específicos de Centaurea que para los cloroplásticos universales específicos de Nicotiana tabacum. A su vez, se obtuvo mejor resultado para las especies de la sección Phalolepis que para las de la sección Lepteranthus. En consecuencia, nuestros resultados apoyan la idea de que el éxito de la amplificación cruzada está estrechamente ligado a la distancia evolutiva entre especie fuente y especie objetivo.Financial support from the Spanish MICINN (Project CGL2007-60781 and CGL2010/18631) and the Generalitat de Catalunya (Ajuts a Grups de Recerca Consolidats 2009/ SGR/00439-GREB) is gratefully acknowledged.Peer reviewe

“Muntanyes i refugis”: investigadors de l’IBB publiquen un estudi genètic sobre endemismes de les muntanyes de Grècia

Noticia publicada en la web institucional del Instituto Botánico de Barcelona el 5 de noviembre de 2015 -- Disponibles PDFs en español y catalán y capturas de pantalla de la noticia en la web.Peer reviewe

Systematics and evolution of the needle grasses (Poaceae: Pooideae: Stipeae) based on analysis of multiple chloroplast loci, ITS, and lemma micromorphology

27 p.We conducted a molecular phylogenetic study of the tribe Stipeae using nine plastid DNA sequences (trnK-matK, matK, trnH-psbA, trnL-F, rps3, ndhF, rpl32-trnL, rps16-trnK, rps16 intron), the nuclear ITS DNA regions, and micromorphological characters from the lemma surface. Our large original dataset includes 156 accessions representing 139 species of Stipeae representing all genera currently placed in the tribe. The maximum likelihood and Bayesian analyses of DNA sequences provide strong support for the monophyly of Stipeae; including, in phylogenetic order, Macrochloa as remote sister lineage to all other Stipeae, then a primary stepwise divergence of three deep lineages with a saw-like (SL) lemma epidermal pattern (a plesiomorphic state). The next split is between a lineage (SL1) which bifurcates into separate Eurasian and American clades, and a lineage of three parts; a small Patis (SL2) clade, as sister to Piptatherum s.str. (SL3), and the achnatheroid clade (AC). The AC exhibits a maize-like lemma epidermal pattern throughout. AC consists of a core clade of Austral-Eurasian distribution and a “major American clade” of North and South American distribution. The base chromosome number for Stipeae is somewhat ambiguous but based on our survey it seems most likely to be x = 11 or 12. Our phylogenetic hypothesis supports the recognition of the following genera and groups (listed by region): Eurasia—Achnatherum, “Miliacea group”, “Neotrinia” (monotypic), Orthoraphium (monotypic), Patis (also 1 from North America), Piptatherum s.str., Psammochloa (monotypic), Ptilagrostis, Stipa, “Timouria group”, and Trikeraia; Mediterranean—Ampelodesmos (monotypic), Celtica (monotypic), Macrochloa (monotypic), and “Stipella-Inaequiglumes group”; Australasia —Anemanthele (monotypic), and Austrostipa; North America (NA)—“Eriocoma group”, Hesperostipa, Oryzopsis (monotypic), Piptatheropsis, “Pseudoeriocoma group”, and “Stillmania” (monotypic); South America—Aciachne, Amelichloa (also NA), Anatherostipa (s.str.), Jarava (polyphyletic), Lorenzochloa, Nassella (also NA), Ortachne, Pappostipa (also NA), and Piptochaetium (also NA). Monophyly of Phaenospermateae including Duthieinae is demonstrated, and its inclusion within or treatment as sister to Stipeae is rejected.Peer reviewe

ISOLATION AND CHARACTERIZATION OF NOVEL MICROSATELLITE MARKERS FOR ARCTIUM MINUS (COMPOSITAE)

[EN] Premise of the study: Microsatellite primers were developed for the invasive plant Arctium minus to investigate the effects of facultative self-pollination and the biannual habit on population genetic structure, as well as the colonization of the Americas by this Eurasian species. Methods and Results: Sixteen di- and trinucleotide microsatellite loci were identifi ed in six populations. The number of alleles per locus ranged from one to 10, observed heterozygosities ranged from 0.000 to 0.897, and the mean value of F IS was 0.316. Conclusions: These results indicate the utility of these loci in future studies of population genetics in A. minus .Peer reviewe

Speciation and genetic diversity in Centaurea subsect. Phalolepis in Anatolia

14 p., mapas, tablasMountains of Anatolia are one of the main Mediterranean biodiversity hotspots and their richness in endemic species amounts for 30% of the flora. Two main factors may account for this high diversity: the complex orography and its role as refugia during past glaciations. We have investigated seven narrow endemics of Centaurea subsection Phalolepis from Anatolia by means of microsatellites and ecological niche modelling (ENM), in order to analyse genetic polymorphisms and getting insights into their speciation. Despite being narrow endemics, all the studied species show moderate to high SSR genetic diversity. Populations are genetically isolated, but exchange of genes probably occurred at glacial maxima (likely through the Anatolian mountain arches as suggested by the ENM). The lack of correlation between genetic clusters and (morpho) species is interpreted as a result of allopatric diversification on the basis of a shared gene pool. As suggested in a former study in Greece, post-glacial isolation in mountains would be the main driver of diversification in these plants; mountains of Anatolia would have acted as plant refugia, allowing the maintenance of high genetic diversity. Ancient gene flow between taxa that became sympatric during glaciations may also have contributed to the high levels of genetic diversity.This work was supported by the Spanish Ministerio de Ciencia e Innovación [project CGL2010/18631] and Generalitat de Catalunya [Ajuts a Grups de Recerca Consolidats 2014-SGR514-GREB]Peer reviewe

Beyond the rand flora pattern : Phylogeny and biogeographical history of Volutaria (compositae)

The Rand Flora describes the disjunct phytogeographical pattern of a wide range of taxa distributed at the periphery of Africa and adjacent islands, as well as the Arabian Peninsula. We focused on Volutaria (Compositae: Cardueae: Centaurineae), a genus of ca. 18 species that conforms to the Rand Flora pattern; yet its phylogeny, interspecific relationships, and biogeographical history remain poorly known. We aim to construct a robust phylogeny that will allow us to interpret the biogeography and the diversification of this genus, together with its present distribution pattern, and to ascertain whether the latter arose by single or multiple gradual expansion processes, vicariance, or long-distance dispersal events. We sampled all extant Volutaria species, covering its entire geographical range, and generated sequences of nuclear-ribosomal DNA and three plastid regions, which were analyzed by Bayesian inference and maximum parsimony. Samples yielding more than one sequence in direct sequencing were cloned. Historical biogeographical analysis was performed using BioGeoBEARS based on a phylogeny dated using a relaxed molecular clock calibrated with a previous dating undertaken for the tribe Cardueae. Volutaria is a monophyletic taxon, having an Asian ancestor, and its present diversity is represented by four main clades that emerged in the Miocene. The earliest taxa of Volutaria to diverge are preserved in North Africa, whereas clades that diverged more recently have done so on both sides of the Sahara. This process involved both ancient and recent interspecific introgression and hybridization events, as indicated by incongruities between plastid and nuclear results, and by cloning of the ITS region. The distribution of Volutaria around two diversity poles conforms to the Rand Flora pattern, but this did not arise by a single event or process. Instead, the historical biogeography of Volutaria involves at least one migration wave from east to west, followed by the extinction of ancestral taxa and subsequent expansion and retraction events, together with speciation processes on both sides of the Sahara. The intense tectonic and climatic changes that occurred in North Africa and western Asia throughout the Neogene and Pleistocene periods might explain the present diversity and distribution pattern of the genus

Influence of the Quaternary Glacial Cycles and the Mountains on the Reticulations in the Subsection Willkommia of the Genus Centaurea

Late Neogene and Quaternary climatic oscillations have greatly shaped the genetic structure of the Mediterranean Basin flora, with mountain plant species tracking warm interglacials/cold glacials by means of altitudinal shifts instead of broad latitudinal ones. Such dynamics may have enhanced population divergence but also secondary contacts. In this paper, we use a case example of subsection Willkommia of Centaurea (comprising three narrowly distributed endemic species, Centaurea gadorensis, C. pulvinata, and C. sagredoi) to test for reticulate evolution and recurrent hybridizations between nearby populations. For this, we combine analyses of genetic diversity and structuring, gene flow and spatial correlation, and ecological niche modeling. Our results support the contention that the current genetic structure of the three species is the result of historical gene flow at sites of secondary contact during the glacial periods, followed by isolation after the retraction of populations to the middle-upper areas of the mountains during the interglacial periods. The extent and direction of the gene flow was determined largely by the location of the populations on mountainsides oriented toward the same valley or toward different valleys, suggesting the intermountain valleys as the areas where secondary contacts occurred

Micromorphology and fatty acid composition of the cypselae of Xeranthemum cylindraceum Sm. (Asteraceae, Cardueae)

The paper presents micromorphology of the cypselae of Xeranthemum cylindraceum as revealed by scanning electron microscopy (SEM) and their fatty acid composition as determined on a gas chromatograph coupled with a flame ionisation detector (GC-FID). The cypselae are densely hairy, straight, ribbed, narrowly obconical to obovoid. Micromorphological features are as follows: striate-rugose surface; adaxial detachment area; asymmetrical carpopodium; presence of biseriate, nonglandular, shortly forked twin hairs; and absence of a pericarp crown. The pappus is paleaceous, homomorphic, uniseriate, persistent, and with several wide, scarious, subulate, and apically pinnulate bristles of variable length. Out of 12 fatty acids detected, nine (88.57%) are identified, ranging from palmitoleic (C16:1) to behenic (C22:0) acids. Oleic acid is dominant (55.24%). Unsaturated fatty acids are predominant in the oil (75.02%). The composition of fatty acids in cypselae of the given species is here reported for the first time. The taxonomic value of the analysed characters is briefly discusse