Publications by authors named "Petr Zakravsky"
We reconstructed the historical pattern of postglacial biogeographic range expansion of the boreal tree species Alnus incana in Europe. To assess population genetic structure and diversity, we performed a combined analysis of nuclear microsatellite loci and chloroplast DNA sequences (65 populations, 1004 individuals). Analysis of haplotype and microsatellite diversity revealed that southeastern refugial populations situated in the Carpathians and the Balkan Peninsula did not spread north and cannot be considered as important source populations for postglacial recolonization of Europe; populations in Eastern Europe did not establish Fennoscandian populations; populations in Fennoscandia and Eastern Europe have no unique genetic cluster, but represent a mix with a predominant cluster typical for Central Europe; and that colonization of Fennoscandia and Eastern Europe took place from Central Europe.
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- This study investigates the distribution and origins of different cytotypes of the plant Alnus glutinosa across Europe, North Africa, and western Asia, highlighting the significance of polyploidy in plant biology.
- Using flow cytometry, microsatellite analysis, and species distribution modeling, the research identifies distinct clusters of tetraploid populations in the Iberian Peninsula and Dinaric Alps, both likely derived from autopolyploid processes rather than hybridization with A. incana.
- The findings suggest that the newly identified tetraploid populations have remained separate from those in central and northern Europe post-glacial retreat, indicating that these regions may not have acted as effective refugia for the
Article Synopsis
- Genetic admixture plays a key role in species expansion by allowing for the selection of beneficial genotypes suited for changing climates, yet comprehensive studies on this phenomenon have been lacking.
- A study on Alnus glutinosa's postglacial history identified multiple southern refuges and three main directions of expansion: north from Iberia, from the Apennines to the Alps, and from the Balkans to Northern Europe.
- The findings suggest that rather than solely originating from the Carpathians, European populations show significant genetic diversity from multiple contact zones, while Mediterranean populations face higher extinction risks due to limited genetic mixing in the face of climate change.
Background/aims: Recently, new palaeoecological records supported by molecular analyses and palaeodistributional modelling have provided more comprehensive insights into plant behaviour during the last Quaternary cycle. We reviewed the migration history of species of subgenus Alnus during the last 50,000 years in Europe with a focus on (1) a general revision of Alnus history since the Last Glacial Maximum (LGM), (2) evidence of northern refugia of Alnus populations during the LGM and (3) the specific history of Alnus in particular European regions.
Methodology: We determined changes in Alnus distribution on the basis of 811 and 68 radiocarbon-dated pollen and macrofossil sites, respectively.
We attempted to confirm that seed banks can be viewed as an important genetic reservoir by testing the hypothesis that standing (aboveground) plants represent a nonrandom sample of the seed bank. We sampled multilocus allozyme genotypes from three species with different life history strategies: Amaranthus retroflexus, Carduus acanthoides, Pastinaca sativa. In four populations of each species we analysed the extent to which allele and genotype frequencies vary in consecutive life history stages including the summer seed bank, which has been overlooked up to now.
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