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1

Genetic diversity of Melica transsilvanica Schur [Poaceae] at its northern range limit

100%
Szczepaniak M., Cieslak E.
Acta Biologica Cracoviensia. Series Botanica
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2009
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tom 51
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nr 1
71-82
Geographically marginal populations are expected to have low genetic variability, which potentially can affect their viability. In Poland Melica transsilvanica Schur reaches the northern limit of its continuous geographical range. Genetic diversity and population genetic structure were analyzed in 15 of its marginal and more central populations using AFLPs. Overall, genetic diversity parameters did not differ significantly, and comparable patterns of genetic variation were found in central and marginal populations. All AFLP phenotypes were unique to particular populations. Unique alleles were fixed in some central and some marginal populations. The percentage of polymorphic loci varied from 1.30 to 5.19 (3.24 average) in central populations and from 0.43 to 5.63 (2.36 average) in marginal ones. Hierarchical analyses of molecular variance (AMOVA) for each species/region combination revealed highly significant differentiation between populations and showed similar partitioning of molecular variance in marginal and central populations of M. transsilvanica (diversity between populations: 93.24% and 93.18%, p < 0.001, respectively). The scattered distribution of suitable species habitats and the predominant selfing breeding system of the species strengthen the effect of selection pressure on fixation of unique loci in individual populations. Marginal populations of M. transsilvanica with unique alleles considerably expand the genetic variation of the species and are therefore valuable for conservation of genetic diversity.
2

Dental anomalies in the Japanese mole Mogera wogura from northeast China and the Primorsky region of Russia

67%
Asahara M., Kryukov A., Motokawa M.
Acta Theriologica
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2012
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tom 57
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nr 1
Dental anomalies in the Japanese mole, Mogera wogura Temminck, 1842, from northeast China and the Primorsky region of Russia were examined based on 241 specimens. The most frequent dental anomaly was oligodonty, i.e., missing P2 (18 cases) or P3 (one case). Supernumerary teeth were observed in three cases, two of which were characterized by abnormal shapes. Morphological abnormalities in teeth (six cases) and an asymmetrically curved rostrum (one case) were also observed. Dental anomalies were found at higher frequencies in populations near the northern range limit of the species. This was not caused by size effects. We suggest that the high incidence of dental anomalies was the result of genetic drift, which increases in marginal populations. Considering the nature of subterranean mammals, our results suggest that the high frequency of dental anomalies in a marginal population could have initiated the evolution of dental formulae if parapatric or peripatric speciation occurs in such populations.
3
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ISSR analysis points to relict character of Aconitum bucovinense Zapal. (Ranunculaceae) at the range margin

67%
Boron P., Zalewska-Galosz J., Sutkowska A., Zemanek B., Mitka J.
Acta Societatis Botanicorum Poloniae
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2011
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tom 80
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nr 4
Aconitum bucovinense, a high-mountain species endemic to the Eastern and Southern Carpathians, including the Apuseni Mountains, is legally protected and classified in the Polish Red Data Book of Plants. It attains its NW geographical range in two peripheral populations in the Western Bieszczady Mountains (Polish Eastern Carpathians), isolated by a distance of 13.1 km. PCR-ISSR analysis has been used to elucidate the within- and among-populational levels of species genetic diversity. A UPGMA and block clustering showed discreteness of the populations and subpopulations based on ISSR banding pattern. Analysis of Molecular Variance (AMOVA) revealed significant divergence (P = 0.024) of the two marginal populations and highly significant (P < 0.001) differentiation of subpopulations within populations. The theta index calculated for the two marginal populations and the core population in the Carpathians was 0.131 ±0.030 S.D. Most of the population-genetic diversity indices of the mar­ginal populations were not different from those in the core area but the Shannon’s and rarity indices were lower in the marginal populations. It seems that founder effect and subsequent genetic bottleneck resulted in a fine-scale population genetic structure. The marginal populations under study need a relevant recovery program to maintain their genetic diversity.
4

Genetic variability of selected marginal populations of Stipa capillata L.

67%
Krzakowa M., Michalak M.
Biological Letters
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2007
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tom 44
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nr 2
127-135
5

Variability of downy oak [Quercus pubescens Willd.] marginal population in Bielinek [North-Western Poland] in morphological traits of leaves

67%
Danielewicz W., Bakowska K., Krzakowa M.
Rocznik Dendrologiczny
|
2002
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tom 50
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