Evolution of Veronica (Plantaginaceae) on the Balkan Peninsula

PHYTOLOGIA BALCANICA 01/2006; 12:231-244.


With more than 6500 species of native seed plants on the Balkans and almost a third of them endemic, the Balkan Peninsula is known to be a place for diversification and formation of new species and an important refugium during the Ice Ages. One plant group, which exemplifies this well, is the genus Veronica (Plantaginaceae, formerly Scrophulariaceae). Four groups from this genus (V. subg. Stenocarpon; V. subg. Chamaedrys; V. subg. Pseudolysimachium, V. alpina-complex) display putative tertiary relict species, speciation within Pleistocene refugia and Pleistocene or Holocene speciation by hybridization and polyploidization on the Balkan Peninsula. I here review earlier published results for these groups and present new data. DNA sequence analyses from the nuclear ribosomal DNA (ITS) and plastid genome (trnLF region) were examined so as to shed more light on the relationship of the species from the Balkans. In addition, AFLP fingerprints were used to study V. subg. Pseudolysimachium, which exhibits limited DNA sequence divergence. Results support the distinctiveness of taxa from the Balkans as a divergent group of plants on the intra-and interspecific level. Limited resolution and support of the results further demonstrate the need for another marker system to continue the study of evolution of these plants of the Balkan Peninsula.

Download full-text


Available from: Dirk Albach
  • Source
    • "Reconstructing the phylogeny of V. subgenus Stenocarpon has been problematic because of the short internal branches relative to the terminal branches (Albach et al., 2005; Albach, 2006). This has prevented delimitation of clades within the subgenus and detection of the correct root using nuclear ribosomal DNA and the plastid trnL-trnL-trnF region (Albach, 2006). The use of other markers both from the nuclear and plastid genome helped detect incongruences between the markers but did not provide a reliable phylogenetic hypothesis for the subgenus or a solution to the rooting problem. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The Balkan Peninsula is considered the most important refugium for species during the Pleistocene glaciations and today harbours c. 2000 endemic species, but we know surprisingly little about the evolution of taxa in this region. Veronica saturejoides, V. thessalica and V. erinoides are a group of closely related alpine taxa endemic to the Balkan Peninsula. Here, we analyse four DNA regions [the nuclear chalcone synthase intron (CHSi) and ribosomal internal transcribed spacer (ITS) region and the plastid rpoB-trnC spacer and trnL-trnL-trnF region] and amplified fragment length polymorphism (AFLP) fingerprints to provide a phylogenetic hypothesis for the relationships among these taxa. Additionally, we analyse leaf morphological characters used to distinguish the three subspecies of V. saturejoides. The analyses support the distinction of the three subspecies based on previously intuitively suggested characters. Nuclear chalcone synthase intron data indicate that the southern taxa are genetically much more diverse than the more northern V. saturejoides subsp. saturejoides. Phylogenetic relationships inferred from this region and AFLP fingerprints support the monophyly of V. saturejoides. In contrast, plastid DNA regions suggest a closer relationship of V. saturejoides subsp. saturejoides to V. thessalica. The most likely scenario involves introgression into V. saturejoides subsp. saturejoides from V. thessalica. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159, 616–636.
    Full-text · Article · Apr 2009 · Botanical Journal of the Linnean Society
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The evolutionary rate at which DNA sequences evolve is known to differ between different groups of organisms. However, the reasons for these different rates are seldom known. Among plants, the generation-time hypothesis, which states that organisms that reproduce faster also have more DNA substitutions per time, has gained most popularity. We evaluate the generation-time hypothesis using 131 DNA sequences from the plastid trnLF region and the nuclear ribosomal ITS region of the genus Veronica (Plantaginaceae). We also examine the alternative hypothesis that a higher substitution rate is correlated with selfing breeding system. Selfing is associated with annual life history in many organisms and may thus often be the underlying reason for observed correlations of annual life history with other characters. We provide evidence that annual life history is more likely to be the responsible factor for higher substitution rates in Veronica than a selfing breeding system. Nevertheless, the way in which annual life history may influence substitution rate in detail remains unknown, and some possibilities are discussed.
    Full-text · Article · Dec 2009 · Journal of Molecular Evolution
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Southeastern Europe is a centre of European biodiversity, but very little is known about factors causing the observed richness. Here, we contribute to fill this gap by reconstructing the spatio-temporal diversification of the cytologically variable and taxonomically intricate complex of Veronica chamaedrys (Plantaginaceae s.l.), growing in open forests, forest edges and grasslands, with flow cytometry, molecular markers (AFLPs, plastid DNA sequences) and morphometry. Our results show that both diploid and tetraploid cytotypes are widespread, but diploids predominate on the southern Balkan Peninsula. Plastid sequences suggest a first split into three main lineages in the mid-Pleistocene and a continuous diversification during the last 0.4 my. Two of the identified plastid lineages coincide with geographically distinct AFLP clusters. Altogether, the genetic data suggest forest refugia on the southern-most Balkan Peninsula (Greece), in Bulgaria, Istria (Croatia and Slovenia) and maybe the southeastern Carpathians (Romania). Morphometric and genetic data show little congruence with current taxonomy.
    Full-text · Article · Nov 2010 · Molecular Phylogenetics and Evolution
Show more