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1.
Sci Rep ; 13(1): 3736, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36878947

RESUMO

The perennial western ragweed (Ambrosia psilostachya DC.) arrived from North America to Europe in the late nineteenth century and behaves invasive in its non-native range. Due to its efficient vegetative propagation via root suckers, A. psilostachya got naturalized in major parts of Europe forming extensive populations in Mediterranean coastal areas. The invasion history, the spreading process, the relationships among the populations as well as population structuring is not yet explored. This paper aims to give first insights into the population genetics of A. psilostachya in its non-native European range based on 60 sampled populations and 15 Simple Sequence Repeats (SSR). By AMOVA analysis we detected 10.4% of genetic variation occurring among (pre-defined) regions. These regions represent important harbors for trading goods from America to Europe that might have served as source for founder populations. Bayesian Clustering revealed that spatial distribution of genetic variation of populations is best explained by six groups, mainly corresponding to regions around important harbors. As northern populations show high degrees of clonality and lowest levels of within-population genetic diversity (mean Ho = 0.40 ± 0.09), they could preserve the initial genetic variation levels by long-lived clonal genets. In Mediterranean populations A. psilostachya expanded to millions of shoots. Some of those were obviously spread by sea current along the coast to new sites, where they initiated populations characterized by a lower genetic diversity. For the future, the invasion history in Europe might get clearer after consideration of North American source populations of western ragweed.


Assuntos
Ambrosia , Asteraceae , Ambrosia/genética , Teorema de Bayes , Europa (Continente) , Análise por Conglomerados
2.
Sci Rep ; 12(1): 19074, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36352030

RESUMO

The Euro-Siberian steppe flora consists of warm- and cold-adapted species, which may have responded differently to Pleistocene glacials and interglacials. Genotyping-by-sequencing individuals from across the distribution range of the pheasant's eye (Adonis vernalis), we aimed to gain insight into steppe florogenesis based on the species' evolutionary history. Although the primary area of origin of the species group comprising A. vernalis, A. villosa and A. volgensis is in Asia, our results indicate that recent populations of A. vernalis are not of Asian origin but evolved in the southern part of Europe during the Pleistocene, with Spanish populations clearly genetically distinct from the Southeastern European populations. We inferred that A. vernalis migrated eastwards from the sub-Mediterranean forest-steppes of Southeastern Europe into the continental forest-steppe zone. Eastern European populations had the highest private allelic richness, indicating long-term large population sizes in this region. As a thermophilic species, A. vernalis seems unlikely to have survived in the cold deserts of the Last Glacial Maximum in Western Siberia, so this region was likely (re)colonized postglacially. Overall, our results reinforce the importance of identifying the area of origin and the corresponding ecological requirements of steppe plants in order to understand the composition of today's steppe flora.


Assuntos
Adonis , Ranunculaceae , Humanos , Genótipo , Evolução Biológica , Europa (Continente) , Filogenia
3.
J Agric Food Chem ; 69(17): 5252-5266, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33877831

RESUMO

Seeds of domesticated Vicia (vetch) species (family Fabaceae-Faboideae) are produced and consumed worldwide for their nutritional value. Seed accessions belonging to 16 different species of Vicia-both domesticated and wild taxa-were subjected to a chemotaxonomic study using ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) analyzed by chemometrics. A total of 89 metabolites were observed in the examined Vicia accessions. Seventy-eight out of the 89 detected metabolites were annotated. Metabolites quantified belonged to several classes, viz., flavonoids, procyanidins, prodelphinidins, anthocyanins, stilbenes, dihydrochalcones, phenolic acids, coumarins, alkaloids, jasmonates, fatty acids, terpenoids, and cyanogenics, with flavonoids and fatty acids amounting to the major classes. Flavonoids, fatty acids, and anthocyanins showed up as potential chemotaxonomic markers in Vicia species discrimination. Fatty acids were more enriched in Vicia faba specimens, while the abundance of flavonoids was the highest in Vicia parviflora. Anthocyanins allowed for discrimination between Vicia hirsuta and Vicia sepium. To the best of our knowledge, this is the first report on employing UPLC-MS metabolomics to discern the diversity of metabolites at the intrageneric level among Vicia species.


Assuntos
Metaboloma , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Flavonoides/análise , Metabolômica , Sementes/química
4.
Insects ; 12(3)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806420

RESUMO

Habitat simplification and intensive use of pesticides are main drivers of global arthropod declines and are, thus, decreasing natural pest control. Organic farming, complex landscapes, and local vineyard management practices such as implementation of flower-rich cover-crop mixtures may be a promising approach to enhance predator abundance and, therefore, natural pest control. We examined the effect of organic versus integrated management, cover-crop diversity in the vineyard inter-rows, and landscape composition on the natural pest control of Lobesia botrana eggs and pupae. Predation of L. botrana pupae was reduced by organic farming and species-poor cover-crops by about 10%. Predation rates of L. botrana eggs did not differ significantly in any of the studied management options. Dominant predators were earwigs (Forficulidae), bush crickets (Tettigoniidae), and ants (Formicidae). Negative effects of organic viticulture are most likely related to the negative nontarget effects on arthropods related to the frequent sulfur and copper applications in combination with the avoidance of strongly damaging insecticides by integrated winegrowers. While a 10% difference in predation rates on a single pest stage is unlikely to have strong practical implications, our results show that the assumed effectiveness of environmentally friendly agriculture needs to be evaluated for specific crops and regions.

5.
Biodivers Conserv ; 28(5): 1245-1265, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30906115

RESUMO

Many steppe species reach their (north)westernmost distribution limit in western Central Europe. This also applies to Poa badensis, a rare steppe plant of calcareous rock/sand vegetation. To explore potential differences in reproductive success and genetic composition of peripheral populations, we analysed the absolute (north)westernmost occurrences in Western Germany and populations at the western margin (Eastern Austria) and the centre (Central Hungary) of the Pannonicum, representing a part of the continuous range. Specifically, we discuss the genetic and reproductive constitution of the (north)westernmost exclave and draw conclusions on the species' biogeographical and conservation history in this region. Therefore, we used two independent molecular marker systems (AFLPs, cpDNA sequences) and a set of performance parameters. Overall, lowest regional genetic diversity was found in Western Germany, which is mainly a result of the specific history of two populations. However, this low genetic diversity was not accompanied by reduced reproductive success. The Eastern Austrian populations showed reduced genetic diversity and predominantly reduced performance, interpreted as a consequence of small population sizes. Central Hungarian populations showed the overall highest genetic diversity and comparatively high performance values. We observed high admixture and haplotype sharing between Austrian and Hungarian populations, indicating gene flow among these regions. In contrast, we interpreted the increased population differentiation within, and the clear distinctiveness of the German exclave as a long-term isolation of these (north)westernmost occurrences. Our results, overall, prove the good constitution of these populations and, together with their particular biogeographical history, highlight their conservation value.

6.
Food Res Int ; 115: 379-392, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599956

RESUMO

Fabaceae is well-known for its seed nutritious and bioactive composition as exemplified by Lupinus and Lens. Developing efficient analytical approaches for profiling their bioactive matrix is a prerequisite to provide proof for their health benefits or nutritive traits. Eight Lupinus and Lens seed accessions were subjected to liquid chromatography-mass spectrometry (UPLC-MS)-based metabolomic study, which identified 66 metabolites, viz. flavonoids, alkaloids, saponins, phenolics, fatty acids and sphingolipids. Chemometric tools were explored to assess heterogeneity across the two genera leading to elucidation of the species-most enriched and differential metabolites. The two dark-colored lentil cultivars are identified as the richest source of functional foods with presumed therapeutic benefits; however, Lupinus hispanicus was proved to be the most nutritive accession. To our knowledge, this study provides the first UPLC-MS-based comparative metabolite profiling of Lupinus and Lens seeds. This platform was also able to discern metabolites diversity at the intraspecific level among Lupinus species and Lens cultivars.


Assuntos
Cromatografia Líquida/métodos , Lens (Planta)/química , Lupinus/anatomia & histologia , Metaboloma , Sementes/química , Espectrometria de Massas em Tandem/métodos , Alcaloides/análise , Áustria , Ácidos Graxos/análise , Flavonoides/análise , Alimento Funcional/análise , Análise Multivariada , Fenóis/análise , Extratos Vegetais/análise , Saponinas/análise , Esfingolipídeos/análise
7.
BMC Ecol ; 18(1): 23, 2018 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-30068321

RESUMO

BACKGROUND: The Spanish slug (Arion vulgaris, also known as A. lusitanicus) is considered one of the most invasive species in agriculture, horticulture and private gardens all over Europe. Although this slug has been problematic for decades, there is still not much known about its occurrence across private gardens and the underlying meteorological and ecological factors. One reason for this knowledge gap is the limited access of researchers to private gardens. Here we used a citizen science approach to overcome this obstacle and examined whether the occurrence of Arionidae in Austrian gardens was associated with meteorological (air temperature, precipitation, global solar radiation, relative humidity) or ecological factors (plant diversity, earthworm activity). Occurrence of the invasive A. vulgaris versus the similar-looking native A. rufus was compared using a DNA-barcoding approach. RESULTS: Slugs were collected from 1061 gardens from the dry Pannonian lowland to the wet alpine climate (altitudinal range 742 m). Slug abundance in gardens was best explained and negatively associated with the parameters "sum of the mean air temperature in spring", "number of frost days in the previous winter" and "mean daily global solar radiation on the day of data collection". Precipitation, plant diversity and earthworm activity were also related to slug abundance, but positively. Out of our genetic sampling of collected slugs, 92% belonged to A. vulgaris. CONCLUSIONS: Our study showed that citizen science (i) is a feasible approach to record species occurrence in restricted areas across a wide geographical range and (ii) could be more widely employed in order to identify underlying environmental factors of species occurrence.


Assuntos
Distribuição Animal , Meio Ambiente , Gastrópodes/fisiologia , Espécies Introduzidas , Tempo (Meteorologia) , Animais , Áustria , Código de Barras de DNA Taxonômico , Jardins , Gastrópodes/genética , Filogenia , Análise de Sequência de DNA
8.
J Agric Food Chem ; 66(16): 4267-4280, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29561614

RESUMO

Lens culinaris and several Lupinus species are two legumes regarded as potential protein resources aside from their richness in phytochemicals. Consequently, characterization of their metabolite composition seems warranted to be considered as a sustainable commercial functional food. This study presents a discriminatory holistic approach for metabolite profiling in accessions of four lentil cultivars and four Lupinus species via gas chromatography/mass spectrometry. A total of 107 metabolites were identified, encompassing organic and amino acids, sugars, and sterols, along with antinutrients, viz., alkaloids and sugar phosphates. Among the examined specimens, four nutritionally valuable accessions ought to be prioritized for future breeding to include Lupinus hispanicus, enriched in organic ( ca. 11.7%) and amino acids ( ca. 5%), and Lupinus angustifolius, rich in sucrose ( ca. 40%), along with two dark-colored lentil cultivars 'verte du Puy' and 'Black Beluga' enriched in peptides. Antinutrient chemicals were observed in Lupinus polyphyllus, owing to its high alkaloid content. Several species-specific markers were also revealed using multivariate data analyses.


Assuntos
Lens (Planta)/química , Lupinus/química , Extratos Vegetais/química , Alcaloides/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lupinus/metabolismo , Valor Nutritivo , Sementes/química , Sementes/metabolismo
9.
Ecol Evol ; 7(16): 6527-6539, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28861254

RESUMO

We investigate patterns of genetic variation along an east-west transect of Central European populations of Linum flavum and interpret the Quaternary history of its peripheral populations, especially those at the westernmost isolated range edge, discussing their migrations and possible relict status. We defined our peripheral transect across three study regions from Central Hungary, eastern Austria to southwestern Germany. Using AFLP fingerprinting and cpDNA sequence variation (rpL16 intron, atpI-H), we analyzed 267 and 95 individuals, respectively, representing each study region by four populations. Hierarchical AMOVA (AFLPs) indicated significant variation among study regions (12% of total variance) and moderate differentiation between populations (10%). Population differentiation was high at the westernmost range edge (11.5%, Germany), but also in the east (13.4%, Hungary), compared to the Austrian study region (8.6%). Correspondingly, AFLP diversity was highest in the center of the study transect in eastern Austria. CpDNA haplotypes support a pattern of regional structuring with the strongest separation of the westernmost range edge, and some haplotype sharing among Austrian and Hungarian individuals. Equilibrating nucleotide versus haplotype diversity patterns, the highly diverse populations at the Pannonian range edge (Austria) indicate long-term persistence, while Central Pannonian populations are obviously effected by recent bottlenecks. Intermediate nucleotide, but high haplotype diversity within the westernmost exclave (Swabian Alb), is indicative of a founder bottleneck during its pre-LGM or early postglacial migration history, followed by sufficient time to accumulate cpDNA variation. The not obviously reduced genetic diversity and distinctiveness of L. flavum at the westernmost range edge suggest a long-term persistence (relict status) of populations in this region, where the species has survived probably even the Würm glaciation in extra-Mediterranean refugia. This genetic relict variation represents an important part of the overall genetic diversity found in the western periphery of this steppe plant and highlights the high conservation priority of respective gene pools.

10.
Appl Veg Sci ; 20(1): 143-158, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28356815

RESUMO

QUESTIONS: What are the main floristic patterns in the Pannonian and western Pontic steppe grasslands? What are the diagnostic species of the major subdivisions of the class Festuco-Brometea (temperate Euro-Siberian dry and semi-dry grasslands)? LOCATION: Carpathian Basin (E Austria, SE Czech Republic, Slovakia, Hungary, Romania, Slovenia, N Croatia and N Serbia), Ukraine, S Poland and the Bryansk region of W Russia. METHODS: We applied a geographically stratified resampling to a large set of relevés containing at least one indicator species of steppe grasslands. The resulting data set of 17 993 relevés was classified using the TWINSPAN algorithm. We identified groups of clusters that corresponded to the class Festuco-Brometea. After excluding relevés not belonging to our target class, we applied a consensus of three fidelity measures, also taking into account external knowledge, to establish the diagnostic species of the orders of the class. The original TWINSPAN divisions were revised on the basis of these diagnostic species. RESULTS: The TWINSPAN classification revealed soil moisture as the most important environmental factor. Eight out of 16 TWINSPAN groups corresponded to Festuco-Brometea. A total of 80, 32 and 58 species were accepted as diagnostic for the orders Brometalia erecti, Festucetalia valesiacae and Stipo-Festucetalia pallentis, respectively. In the further subdivision of the orders, soil conditions, geographic distribution and altitude could be identified as factors driving the major floristic patterns. CONCLUSIONS: We propose the following classification of the Festuco-Brometea in our study area: (1) Brometalia erecti (semi-dry grasslands) with Scabioso ochroleucae-Poion angustifoliae (steppe meadows of the forest zone of E Europe) and Cirsio-Brachypodion pinnati (meadow steppes on deep soils in the forest-steppe zone of E Central and E Europe); (2) Festucetalia valesiacae (grass steppes) with Festucion valesiacae (grass steppes on less developed soils in the forest-steppe zone of E Central and E Europe) and Stipion lessingianae (grass steppes in the steppe zone); (3) Stipo-Festucetalia pallentis (rocky steppes) with Asplenio septentrionalis-Festucion pallentis (rocky steppes on siliceous and intermediate soils), Bromo-Festucion pallentis (thermophilous rocky steppes on calcareous soils), Diantho-Seslerion (dealpine Sesleria caerulea grasslands of the Western Carpathians) and Seslerion rigidae (dealpine Sesleria rigida grasslands of the Romanian Carpathians).

11.
Anal Bioanal Chem ; 408(28): 8065-8078, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27614978

RESUMO

Trigonella foenum-graecum is a plant of considerable value for its nutritive composition as well as medicinal effects. This study aims to examine Trigonella seeds using a metabolome-based ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) in parallel to gas chromatography-mass spectrometry (GC-MS) coupled with multivariate data analyses. The metabolomic differences of seeds derived from three Trigonella species, i.e., T. caerulea, T. corniculata, and T. foenum-graecum, were assessed. Under specified conditions, we were able to identify 93 metabolites including 5 peptides, 2 phenolic acids, 22 C/O-flavonoid conjugates, 26 saponins, and 9 fatty acids using UPLC-MS. Several novel dipeptides, saponins, and flavonoids were found in Trigonella herein for the first time. Samples were classified via unsupervised principal component analysis (PCA) followed by supervised orthogonal projection to latent structures-discriminant analysis (OPLS-DA). A distinct separation among the investigated Trigonella species was revealed, with T. foenum-graecum samples found most enriched in apigenin-C-glycosides, viz. vicenins 1/3 and 2, compared to the other two species. In contrast to UPLC-MS, GC-MS was less efficient to classify specimens, with differences among specimens mostly attributed to fatty acyl esters. GC-MS analysis of Trigonella seed extracts led to the identification of 91 metabolites belonging mostly to fatty acyl esters, free fatty acids followed by organic acids, sugars, and amino acids. This study presents the first report on primary and secondary metabolite compositional differences among Trigonella seeds via a metabolomics approach and reveals that, among the species examined, the official T. foenum-graecum presents a better source of Trigonella secondary bioactive metabolites.


Assuntos
Metaboloma , Metabolômica/métodos , Extratos Vegetais/metabolismo , Sementes/metabolismo , Trigonella/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Análise Multivariada , Análise de Componente Principal
12.
Mol Phylogenet Evol ; 54(2): 607-16, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19825422

RESUMO

The numerous disjunct plant distributions between Macaronesia and eastern Africa-Arabia suggest that these could be the relicts of a once continuous vegetation belt along the southern Tethys, which has been fragmented by Upper Miocene-Pliocene aridification. We tested this vicariance hypothesis with a phylogenetic analysis of Campylanthus (Plantaginaceae), based on nuclear and plastid DNA sequence data. Our results indicate a basal split within Campylanthus giving rise to Macaronesian and Eritreo-Arabian lineages in the Pliocene/Upper Miocene. This is consistent with the vicariance hypothesis, thus obviating the need to postulate trans-Saharan long-distance dispersal. The biogeography of Campylanthus may parallel patterns in other plant groups and the implications for our understanding of the biogeography of northern and eastern Africa, and Arabia are discussed.


Assuntos
Evolução Molecular , Filogenia , Plantago/genética , África Oriental , Teorema de Bayes , Núcleo Celular/genética , DNA de Plantas/genética , Geografia , Funções Verossimilhança , Oriente Médio , Plantago/classificação , Plastídeos/genética , Alinhamento de Sequência , Análise de Sequência de DNA
13.
Mol Ecol ; 18(4): 697-708, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19175503

RESUMO

The dating of recent events in the history of organisms needs divergence rates based on molecular fingerprint markers. Here, we used amplified fragment length polymorphisms (AFLPs) of three distantly related alpine plant species co-occurring in the Spanish Sierra Nevada, the Pyrenees and the southwestern Alps/Massif Central to establish divergence rates. Within each of these species (Gentiana alpina, Kernera saxatilis and Silene rupestris), we found that the degree of AFLP divergence (D(N72)) between mountain phylogroups was significantly correlated with their time of divergence (as inferred from palaeoclimatic/palynological data), indicating constant AFLP divergence rates. As these rates did not differ significantly among species, a regression analysis based on the pooled data was utilized to generate a general AFLP rate. The application of this latter rate to AFLP data from other herbaceous plant species (Minuartia biflora: Schönswetter et al. 2006; Nigella degenii: Comes et al. 2008) resulted in a plausible timing of the recolonization of the Svalbard Islands and the separation of populations from the Alps and Scandinavia (Minuartia), and of island population separation in the Aegean Archipelago (Nigella). Furthermore, the AFLP mutation rate obtained in our study is of the same magnitude as AFLP mutation rates published previously. The temporal limits of our AFLP rate, which is based on intraspecific vicariance events at shallow (i.e. late glacial/Early Holocene) time scales, remains to be tested.


Assuntos
Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Evolução Molecular , Genética Populacional , Plantas/genética , Brassicaceae/genética , Caryophyllaceae/genética , DNA de Plantas/genética , Ecossistema , Europa (Continente) , Gentiana/genética , Modelos Genéticos , Mutação , Filogenia , Análise de Regressão , Análise de Sequência de DNA , Especificidade da Espécie
14.
Oecologia ; 155(3): 497-508, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18060434

RESUMO

Among the factors thought to have favoured the evolution of deception (rewardlessness) in orchids is the reduction of pollinator-mediated selfing when unrewarded pollinators visit fewer flowers per inflorescence. We obtained data on natural levels of geitonogamy in the deceptive orchids Dactylorhiza sambucina and Himantoglossum hircinum by monitoring the dispersal and receipt of colour-coded pollinia. As donors, we marked 185 flowers of D. sambucina and 956 flowers of H. hircinum. In D. sambucina, 30% of the pollinator-visited flowers and 62% of the marked inflorescences experienced geitonogamous pollination events. In H. hircinum, the respective percentages were 36 and 71%. The furthest pollen transport distance in the Andrena-pollinated H. hircinum was 6.9 m (median 1.27 m), while the furthest transport in the bumblebee-pollinated D. sambucina was 176 m (median 1.23 m), a record in Orchidaceae. An analysis of pollen-tracking studies in orchids revealed geitonogamy levels of around 40% (based on individuals; 19-37% based on flowers) in both rewardless species and rewarding ones. This is similar to geitonogamy levels in other animal-pollinated angiosperms, although the data basis for comparison may still be too small. So far, however, it is not evident that rewardless orchids experience particularly low levels of geitonogamy.


Assuntos
Abelhas/fisiologia , Flores/fisiologia , Endogamia , Orchidaceae/fisiologia , Polinização/fisiologia , Animais
15.
New Phytol ; 172(1): 169-84, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16945099

RESUMO

Here, we investigated the origin and genetic diversity of four alpine plant species co-occurring in the Spanish Sierra Nevada and other high mountains in south-western Europe by analysis of amplified fragment length polymorphisms (AFLPs). In Kernera saxatilis, Silene rupestris and Gentiana alpina we found intraspecific phylogroups corresponding to mountain regions as predicted by the vicariance hypothesis. Moreover, genetic distances between Sierra Nevada and Pyrenees populations were always higher than those between populations from the Pyrenees and the south-western Alps/Massif Central. This suggests successive disruption of gene exchange between mountain ranges as postglacial climatic warming proceeded from south to north. In Papaver alpinum, our data indicate that a central Pyrenean population arose via long-distance dispersal from the Sierra Nevada, and that vicariant separation events between the Sierra Nevada and the Pyrenees and between the Pyrenees and the south-western Alps occurred simultaneously. Overall, Sierra Nevada populations of all species investigated here preserve unexpectedly high (or not exceptionally reduced) genetic diversity. This testifies to the important influence of long-term isolation, i.e. vicariance, on genetic diversity through fostering the accumulation of new mutations and/or the fixation of ancestral ones.


Assuntos
Brassicaceae/fisiologia , Gentiana/fisiologia , Geografia , Papaver/fisiologia , Polimorfismo Genético , Silene/fisiologia , Brassicaceae/genética , Ecossistema , Gentiana/genética , Papaver/genética , Filogenia , Silene/genética , Espanha
16.
Mol Ecol ; 12(4): 931-49, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12753213

RESUMO

Nuclear DNA sequence variation of the internal transcribed spacer (ITS) and amplified fragment length polymorphisms (AFLPs) were used to illuminate the evolutionary history of Pritzelago alpina, a herbaceous perennial of (sub)alpine to nival habitats of the European high mountains. Maximum likelihood analysis of ITS sequences of P. alpina, Hornungia petraea and Hymenolobus procumbens (the 'Pritzelago alliance') resolved P. alpina and H. petraea as sister taxa. ITS divergence estimates support an origin for P. alpina in the Late Tertiary, while intraspecific diversification started in the Late Quaternary (0.4-0.9 million years ago). AFLP analysis of 76 individuals of P. alpina, representing 24 localities across its entire west-east distribution, identified four mountain lineages in Cantabria, the Pyrenees, (south-) western Alps, and northeastern Alps/Tatras/Carpathians. In an analysis of molecular variance (amova), 14.3% of the total variation derived from this separation. However, relationships among these lineages remained unresolved in neighbour-joining and principal co-ordinates analyses, suggesting a population history of near simultaneous vicariance. Comparison with our previous ITS/AFLP study of Anthyllis montana (Fabaceae) indicates that the two co-distributed but altitudinally differentiated plant species exhibit temporally concordant but spatially discordant patterns of genetic variation. Moreover, levels of AFLP divergence were significantly lower in P. alpina than in the submediterranean, lower-elevation A. montana. Together, these data are consistent with a 'displacement refugia model', which predicts that European mountain plant species associated with lower- and upper-elevation habitats had a different cycle of range contraction into (long-term) glacial and (short-term) interglacial refugia, respectively.


Assuntos
Brassicaceae/genética , Brassicaceae/fisiologia , DNA de Plantas/genética , Filogenia , Sequência de Bases , Análise por Conglomerados , Impressões Digitais de DNA , Primers do DNA , Europa (Continente) , Variação Genética , Geografia , Funções Verossimilhança , Dados de Sequência Molecular
17.
Mol Ecol ; 11(3): 447-63, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11918780

RESUMO

Anthyllis montana is a submediterranean, herbaceous plant of the southern and central European mountains. The internal transcribed spacer (ITS) regions of nuclear ribosomal DNA were sequenced from multiple accessions of the species and several closely related taxa. In addition, amplified fragment length polymorphism (AFLP) was analysed from 71 individuals of A. montana collected in 20 localities, mainly in the Pyrenees, Alps, Italian Peninsula and Balkans. Our ITS phylogeny showed a sequential branching pattern in A. montana, implying a western Mediterranean origin followed by an eastward migration. ITS clock calibrations suggest that speciation of A. montana took place at the Pliocene-Pleistocene boundary, while intraspecific divergence dates to Late Quaternary times (i.e. 0.7 million years ago). The AFLP analyses revealed a major genetic (west/east) subdivision within A. montana, probably caused by the massive glaciation of the Alps during this latter time period. The present-day absence of A. montana from vast parts of the Alps, which appear ecologically suitable for the species, together with the finding of evenly distributed AFLP variability within each of the two western and eastern lineages identified, is taken as evidence for a largely static Late Quaternary history without large-scale migration. High levels of AFLP variation observed among populations, together with weak or absent patterns of isolation by distance, seem to be in accord with long-term population insularization and distributional stasis. However, recent small-scale migration and a narrow hybrid zone between western and eastern lineages need to be postulated to explain the intermediate genetic composition of individuals from the Maritime Alps, a well-known suture-zone for other plant and animal species.


Assuntos
DNA Espaçador Ribossômico/genética , Fabaceae/genética , Marcadores Genéticos , Fabaceae/classificação , Genes de Plantas , Geografia , Biologia Molecular , Técnicas de Amplificação de Ácido Nucleico , Filogenia , Análise de Sequência de DNA
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