Phylogenetic relationships between

The article examines the genetic diversity in 54 populations of 9 Chondrilla species (C. acantholepis, C. ambigua, C. brevirostris, C. canescens, C. graminea, C. juncea, C. laticoronata, C. latifolia, and C. pauciflora) in European Russia. Plastid DNA segments trnT–trnF are selected as markers. Reconstruction of evolutionary networks based on the principle of maximum parsimony reveals that the sample is divided into four groups, where group 1 is C. ambigua, 2 – C. brevirostris, 3 – C. laticoronata, 4 – C. acantholepis, C. canescens, C. graminea, C. juncea, and C. latifolia. The findings show that C. acantholepis, C. canescens, C. graminea, C. juncea and C. latifolia are to be treated as synonyms under the name of C. juncea

Phylogenetic relationships between Chondrilla L. species in European Russia based on plastid DNA sequencing

The article examines the genetic diversity in 54 populations of 9 Chondrilla species (C. acantholepis, C. ambigua, C. brevirostris, C. canescens, C. graminea, C. juncea, C. laticoronata, C. latifolia, and C. pauciflora) in European Russia. Plastid DNA segments trnT–trnF are selected as markers. Reconstruction of evolutionary networks based on the principle of maximum parsimony reveals that the sample is divided into four groups, where group 1 is C. ambigua, 2 – C. brevirostris, 3 – C. laticoronata, 4 – C. acantholepis, C. canescens, C. graminea, C. juncea, and C. latifolia. The findings show that C. acantholepis, C. canescens, C. graminea, C. juncea and C. latifolia are to be treated as synonyms under the name of C. juncea

Molecular Phylogeny and Phylogeography of Potentilla multifida L. agg. (Rosaceae) in Northern Eurasia with Special Focus on Two Rare and Critically Endangered Endemic Species, P. volgarica and P. eversmanniana

The results of a molecular genetic study of Potentilla multifida agg. using two plastid markers (ndhC-trnV and psbA-trnH) and a nuclear ITS marker suggested that this group comprises a number of relatively young and incompletely differentiated species widely distributed in Northern Eurasia. The sequences were analyzed using tree-based (maximum likelihood) and network-based (statistical parsimony network) approaches. The plastid data suggested incomplete lineage sorting, characteristic of the group as a whole. The nuclear ITS results demonstrated quite a different pattern, with mostly conspecific accessions shaping monophyletic clades. The majority of the Potentilla sect. Multifidae species studied possess few, usually closely related plastid haplotypes, or are even monomorphic. In contrast, P. volgarica, a narrow endemic from the Volga River valley, presents plastid haplotypes belonging to two distantly related groups. Such a pattern of genetic diversity in P. volgarica may be explained by a long persistence of the species within an extremely small distribution range, on the right bank of the Volga River, most likely representing a contemporary refugium. The genealogy of plastid markers in P. volgarica suggests that this species is ancestral to P.eversmanniana, another narrow endemic from the S Urals

Admixture facilitates adaptation from standing variation in the European aspen (Populus tremula L.), a widespread forest tree

Adaptation to new environments can start from new mutations or from standing variation already present in natural populations. Whether admixture constrains or facilitates adaptation from standing variation is largely unknown, especially in ecological keystone or foundation species. We examined patterns of neutral and adaptive population divergence in Populus tremula L.;a widespread forest tree, using mapped molecular genetic markers. We detected the genetic signature of postglacial admixture between a Western and an Eastern lineage of P. tremula in Scandinavia, an area suspected to represent a zone of postglacial contact for many species of animals and plants. Stringent divergence-based neutrality tests provided clear indications for locally varying selection at the European scale. Six of 12 polymorphisms under selection were located less than 1 kb away from the nearest gene predicted by the Populus trichocarpa genome sequence. Few of these loci exhibited a signature of 'selective sweeps' in diversity-based tests, which is to be expected if adaptation occurs primarily from standing variation. In Scandinavia, admixture explained genomic patterns of ancestry and the nature of clinal variation and strength of selection for bud set, a phenological trait of great adaptive significance in temperate trees, measured in a common garden trial. Our data provide a hitherto missing direct link between past range shifts because of climatic oscillations, and levels of standing variation currently available for selection and adaptation in a terrestrial foundation species. © 2010 Blackwell Publishing Ltd

Phylogeography of the European rock rose Helianthemum nummularium s.l. (Cistaceae) : western richness and eastern poverty

Helianthemum nummularium s.l. is a young, morphologically diverse species distributed from western Europe to the Caucasus and the Southern Urals in the east. We analysed the rps16-trnK plastid intergenic spacer sequences from 85 localities covering most of the range of H. nummularium. Thirteen haplotypes were very unevenly distributed throughout the range of the species, and exhibited a strong phylogeographic signal. The results confirm range expansions of H. nummularium from Mediterranean refugia northwards, but also show the major role of eastern European (the Caucasus and the Southern Urals) refugia in rapid postglacial colonization of east, north and central Europe. The plastid haplotypes form distinct clades, one representing an eastern European lineage with few haplotypes and the other representing a western European lineage with many haplotypes. Parallel to this split in haplotype diversity is the pronounced differentiation in morphological variation displayed by the taxa found in west and east Europe. We discuss the role of topography in generating differences in morphological and genetic diversity between these two groups. We also discuss the taxonomical status of Helianthemum arcticum, which is regarded as an endangered local endemic of the Kola Peninsula. Helianthemum arcticum appears to represent an outlying peripheral population of H. nummularium preserved since the last postglacial major range expansion of this species, and bears the same plastid haplotype as the bulk of east and north European populations

Is Salix fursaevii Mavrodiev (Salicaceae) a palaeoendemic of the Volga River valley or an ecotype of S. triandra L.?

Salix fursaevii, a species endemic to the Volga River flood plain, was described by E. Mavrodiev and co-authors in Byull. Moskovsk. Obshch. Isp. Prir. in 2012. It differs from the closely related and widespread S. triandra by a few quantitative morphological characters and, most of all by its much later flowering time. This late-flowering willow was known and studied before as an ecotype of S. triandra. Our study of a large sample of S. triandra s. l. revealed that 1) S. triandra s. str. and S. fursaevii could not be clearly distinguished using several morphological characters and the time of flowering; 2) specimens morphologically corresponding to S. fursaevii are with a single exception strictly confined to the Volga River flood plain; 3) the populations of S. triandra and S. fursaevii do not differ by nrITS sequences; 4) the populations of S. triandra and S. fursaevii are poorly differentiated by chloroplast atpB-rbcL sequences; 5) representatives of both taxa are tetraploids 2n = 4x = 76. Poor differentiation of populations by chloroplast sequences is indicative of the intraspecific variability, the geographic pattern of which suggests that the Volga River valley was a probable glacial refugium and a source of post glacial spread of S. triandra

Genome size variation in Deschampsia cespitosa sensu lato (Poaceae) in Eurasia

The grass Deschampsia cespitosa is a variable taxon out of which many varieties, subspecies and endemic species have been separated. In this paper, the variation in genome size (GS) and ploidy of this grass including several of its subspecies and two related species in Eurasia was investigated by flow cytometric (FCM) measurements. GS and ploidy data were also related to specific environments and reproduction mode. Ploidy levels found by FCM were confirmed by chromosome counts of diploid (2n = 28) and tetraploid (2n = 52) samples. Seminiferous (seed bearing) D. cespitosa was mainly diploid (GS between 3.754 and 5.438 pg/1C). GS variation in diploids showed a geographic pattern with a significant difference (H = 41,441, P < 0.001) between European (median = 4.377 pg) and Asian (median = 4.881 pg) accessions. Genome size (1C) in tetraploids ranged from 7.9426 to 9.0399 pg. Tetraploid seminiferous D. cespitosa was found mostly in disturbed habitats in western and southern Europe, while tetraploids in Asia were registered in wet Arctic habitats. Genome size (1C between 8.3278 and 8.8603 pg) of the pseudoviviparous plants (spikelets produce plantlets asexually) of wet habitats in central and northern Europe indicated tetraploidy. A putative triploid (GS 6.6817 pg) was detected in Iceland. Summing up, we found a high variation in GS on the geographic scale with significant regional differences in diploid D. cespitosa. Among the tetraploids, the asexually reproducing plants were bound to specific habitats, while the seminiferous plants showed a habitat preference similar to the diploids.Fil: Greimler, Josef. Universidad de Viena. Instituto de Botanica; AustriaFil: Temsch, Eva M.. Universidad de Viena. Instituto de Botanica; AustriaFil: Xue, Zhiqing. Universidad de Viena. Instituto de Botanica; AustriaFil: Weiss Schneeweiss, Hanna. Universidad de Viena. Instituto de Botanica; AustriaFil: Volkova, Polina. Papanin Institute For Biology Of Inland Waters Ras; RusiaFil: Peintinger, Markus. Swiss Federal Research Institute; SuizaFil: Wasowicz, Pawel. Icelandic Institute Of Natural History; IslandiaFil: Shang, Hui. Shanghai Chenshan Plant Science Research Center; ChinaFil: Schanzer, Ivan. Tsitsin Main Botanical Garden Ras; RusiaFil: Chiapella, Jorge Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin