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tom 73
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nr 3
EN
The paper presents results of biosystematic analysis of the critical group of Caltha palustris L. based on 71 populations from Poland. After a preliminary statistical analysis, fourteen morphological characters (nine quantitative and five qualitative), describing size and shape of basal leaves and mature follicles as well as stem morphology, were selected for the clearest differentiation of the complex. Several groups of morphotypes were distinguished within the complex, based on the statistical analysis of this group of characters. Against this background the taxonomy of the complex is proposed. Two species - Caltha laeta Schott, Nyman and Kotschy and Caltha palustris L. - and three subspecies within C. palustris (C. p. subsp. palustris, C. p. subsp. cornuta (Schott, Nyman and Kotschy) Hegi and C. p. subsp. radicans (T.F. Forst.) Syme, were distinguished in Poland. The status of the taxa within the Polish flora is defined. The paper includes also a key for determination of the complex taxa, as well as their detailed descriptions.
EN
Galium sect. Leptogalium Lange in NE Europe is represented by few, local endemic species which occur in the area covered by the continental ice sheet in the Pleistocene period. They are: G. cracoviense Ehrend. in S Poland, G. oelandicum (Sterner & Hyl.) Ehrend. in SE Sweden and G. sudeticum Tausch in SW Poland and N Czech Republic. 55 individuals from five populations of these species were analysed using AFLP markers. A total of 193 AFLP bands were detected using three combinations of primers; out of them 159 proved polymorphic (82.4%). The lowest values of Shannon's index and Nei's gene diversity were noted for G. oelandicum and the highest ones for G. sudeticum. The results indicate a relatively high level of genetic variability in each of endemic species in spite of that the studied species occupy very small areas and are represented by a low number of populations. We conclude that additional, demographic and genetic studies are necessary to monitor potential decrease of populations' size resulting mainly from the mechanical destruction of plants and their habitats caused by intense tourism or other human activities (as agriculture, e.g. grazing).
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nr 4
321-331
EN
Fragmented distribution, the breeding system and effects of genetic drift in small-size populations occurring at edge of the species range play an important role in shaping genetic diversity of such a species. Melica transsilvanica is a plant rare in the flora of Poland, where it reaches the northern limit of its continuous range. Amplified Fragment Length Polymorphism (AFLP) DNA profiling method was applied to measure genetic diversity among and within populations of M. transsilvanica. Additionally, genetic relationships between M. transsilvanica and Melica ciliata, two closely related species, were explored. A total of 68 plants from 7 populations of M. transsilvanica and 24 plants from 2 populations of M. ciliata, collected in Poland and outside it, were analyzed. Using 294 AFLP fragments from 3 primer combinations, accessions were grouped into two major clusters associating with M. ciliata and M. transsilvanica, respectively. Further, two subclusters, corresponding to the samples collected from the Pieniny Mts and from the Kraków - Częstochowa Upland were clearly distinguished within the M. transsilvanica group. The hierarchical AMOVA exhibited significant genetic distinction between these geographic regions (60.89%, p < 0.001). The obtained results showed that the most genetic diversity resided between the populations of M. transsilvanica (86.03%) while considerably lower genetic variation was found within the populations (13.97%), which is consistent with the results reported for self-plants. The low level of AFLP genetic variation of M. transsilvanica can be caused by the geographic isolation of populations, which preserves the dominant self-mating breeding system of the species. Individual populations of M. transsilvanica are characterized by isolated gene pools differing by a small number of loci.
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2011
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tom 80
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nr 4
EN
A good knowledge of species delimitation is crucial for the biodiversity protection and the conservation of wild species. We studied the efficiency of AFLP markers and morphological characters to assist species determination for Melica ciliata L. and M. transsilvanica Schur within European range of distribution, including isolated and range-limit populations of "M. ciliata" (i.e. M. cf. ciliata) from the Polish Sudetes, where it is regarded as critically endangered. AFLP markers were found to be more effective then morphological characters (more or less continuous) in distinguishing the both studied species. AMOVA revealed very low genetic diversity within populations and high differentiation among populations of M. ciliata and M. transsilvanica (FST = 0.89 and 0.95, respectively). The species-diagnostic AFLP markers of M. transsilvanica shared with "M. ciliata" from the Sudetes were detected. On the other hand, no species-diagnostic genetic markers of M. ciliata or hybrid-diagnostic markers of M. × thuringiaca were found within "M. ciliata". PCoA and NJ showed an overlapping genetic diversity of "M. ciliata" and M. transsilvanica. Hierar­chical AMOVA supported the absence of a significant genotypic distinction between "M. ciliata" and M. transsilvanica. ANOVA showed that the length ratio of lower to upper glumes was the best morphological character to discriminate between M. ciliata and M. transsilvanica. Combined morphological and genetic data show that M. ciliata is not currently present in Poland as its putative Polish populations represent M. transsilvanica. A significant decrease in genetic varia­bility that could influence viability was not observed the in Sudetian populations of M. transsilvanica. However, the population size changes significantly as a result of plant succession. Correction of the northern limit of the continuous distribution of M. ciliata L. in Central Europe is presented.
EN
Cochlearia polonica Fröhl. (Brassicaceae) is one of the rarest species in the Polish and European flora and a taxon endemic to a very small area in southern Poland. Due to industrial activities and subsequent transformation of habitats it was extinct in all natural localities around 1994. The persistence of the species was ensured thanks to the active protection efforts including a series of transplantations based on the material from the last and decreasing natural population. The history of conservation efforts of C. polonica provides a model example of successful active protection in the European flora. Here, we provide a complete review comprising the following aims: (i) outline of the discovery and taxonomic conceptions on C. polonica, (ii) review of conservation efforts aimed at preserving its populations, (iii) description of the existing population resources, and (iv) analysis of the genetic structure of all existing populations based on previously published data and new, supplementary results.
EN
Combined morphological and molecular techniques were used to characterize variation in Elymus repens. We studied the morphological variability of E. repens in relation to the degree of its genetic differentiation, in order to unravel the causes of conspicuous intraspecific morphological variation. Four populations of E. repens from different habitats were analyzed for 35 morphological characters, and their genetic differentiation was assessed by Amplified Fragment Length Polymorphism (AFLP). Four pairs of selective primers were used to detect a total of 279 AFLP bands, of which 104 (37.28%) were polymorphic between populations. Cluster analysis based on AFLP fingerprint data showed that individuals were arranged in population-specific groups. The analyses of variance (ANOVA and AMOVA) indicated significant morphological and genetic differentiation among populations (P<0.01). This study revealed low levels of AFLP variation, which suggests that conspicuous morphological variation of E. repens is caused by plasticity. E. repens is an evolutionarily young species, of hybrid origin, in which microevolutionary processes continue. This study showed that common analysis of genetic diversity and morphology is a powerful tool in low-level taxonomy.
EN
Hybrid speciation within the genus Elymus is analyzed and discussed. The supposed hybrid origin of Elymus x mucronatus between Elymus repens and Elymus hispidus was tested. In this aim, pollen viability and AFLP variation of putative progenitors and progenies from two natural populations were studied. Pollen fertility of hybrids ranging from 0 to 91.95% (average 59.50%) indicates the occurrence of F1 hybrids and backcross hybrids. Seven EcoRI/MseI AFLP primer combinations generated a total of 477 AFLP fragments (300 polymorphic) for 48 parental and hybrid individuals. UPGMA and principal coordinates analysis of the AFLP data set show that hybrids are closer to E. hispidus than to E. repens and suggest unidirectional introgression towards E. hispidus. AFLP fragments of the hybrid taxon were additively inherited from the parental species and no hybrid-specific bands were identified. AFLP analysis validates the hybrid status of E. ×mucronatus. Populations in which E. repens, E. hispidus and their hybrids co-occur still progress from early hybridization stages of F1 hybrids to an advanced hybridization stage of a well-established hybrid swarm. E. ×mucronatus is potentially self-sustaining by predominant vegetative reproduction by rhizomes and partial fertility leading to the development of mature seeds. We propose to consider Elymus ×mucronatus as a new species of hybrid origin in the Polish flora.
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