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1
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Genetic diversity in Vernonia amygdalina Delile accessions revealed by random amplified polymorphic DNAs (RAPDs)

100%
Aikpokpodion P., Abebe J., Igwe D.
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
|
2018
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tom 99
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nr 2
2

Comparative chemical composition of the essential oil of Thymus vulgaris L. from different geographical sources

100%
Raal A., Arak E., Orav A.
Herba Polonica
|
2005
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tom 51
|
nr 1-2
Variations in the essential oil composition of Thymus vulgaris L. cultivated in Estonia and in other European countries were determined using capillary gas chromatographic analysis methods. Fifty-nine components were identified, representing over 95% of the total oil yield. The principal components in the oils of common thyme were thymol (0.9%-75.7%), carvacrol (1.5%-83.5%), p-cymene (4.3%-34.4%), y-terpinene (0.9%-19.7%), linalool (0.4V 4.8%), (E)-ß-caryophyllene (0.5%-9.3%) and terpinen-4-ol (tr.-3.8%). The sum of phenolic compounds (thymol and carvacrol) in the oils studied varied from 19.4% to 84.4%, and the sum of their precursors (p-cymene and y-terpinene) ranged from 5.7% to 38.5%. Thymol content was predominant in the oils of Holland (65.5%) and of Estonia (75.7%) but carvacrol content predominated in the Greek thyme oil (83.5%). Armenian thyme oil contained only 17.0% of thymol, but it was rich in neral and citronellol (32.5%), borneol (4.3%), citronellal (4.0%), 1,8-cineoI (4.0%) and methyl eugenol and thymol acetate (7.5%). In Estonia, the thymol, thymol-carvacrol and thymol-p-cymene-y-terpinene chemotypes of the common thyme are distinguishable.
3

Geographical differentiation of species within some genera of Isotomidae [Collembola]

100%
Potapov M. B.
Polskie Pismo Entomologiczne
|
1995
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tom 64
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nr 1-4
4
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
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Pinus mugo Turra geographic differentiation based on needle characters

84%
Boratynska K., Muchewicz E., Drojma M.
Dendrobiology
|
2004
|
tom 51
9-17
The needles of 17 samples representing 15 populations of Pinus mugo Turra from the Alps, Apennines, Sudethians, Carpathians and Rhodopes were analysed in respect to 15 morphological and anatomical characters. The results of measurements were analysed statistically. The variation of the samples was generally not to large. Populations from the East Carpathians appeared different from all other examined. Two formed groups of analysed populations are separated mainly by thickness of epidermal cells, width/thickness of epidermal cell ratio, needle width and needle thickness. The differences between two groups of populations suggest their longer separation during Pleistocene.
5
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Morphological variability of leaves of Sorbus domestica L. in Croatia

84%
Poljak I., Kajba D., Ljubic I., Idzojtic M.
Acta Societatis Botanicorum Poloniae
|
2015
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tom 84
|
nr 2
The paper studies the morphological variability of the service tree populations in the continental and Mediterranean regions of Croatia. The inter- and intra-population variability, as well as eco-geographic population differentiation, was established on the basis of eight measured morphological characteristics of two types of leaflets (lateral and terminal) and two derived ratios, using descriptive and multivariate statistical methods. The conducted research established a high variability of morphological characteristics. In comparison with lateral leaflets, terminal leaflets showed a higher degree of variability for the majority of the studied variables. The differences between the trees within populations, as well as the differences between populations, were confirmed for all studied characteristics. The study also confirmed a trend of population variations according to the eco-geographic principle. Populations from climatically different and geographically distant habitats, in other words from the Mediterranean and the continental region, differed in the majority of studied characteristics. In addition to the established pattern of ecotypical variability between the continental and the Mediterranean regions, the clinal variability with regard to altitude and mean annual temperature was also confirmed. Small, although statistically significant clinal variability with regard to the longitude was recorded for two measured characteristics. The conducted study provided insights into the variability of the service tree populations in Croatia, which is a basis for further research that should be implemented in order to produce guidelines for the breeding and conservation of genetic resources of this rare and endangered noble hardwood species.
6

Local variability of soil properties of forest stands along the North-South climatic transect in Europe

84%
Degorski M.
Polish Journal of Ecology
|
2003
|
tom 51
|
nr 4
The differentiation of the properties of soils at the level of pedons constitutes one of the most essential elements of the functional-structural analysis of the ecosystems. The purpose of the studies presented in this paper was to assess the spatial variability of the soil cover as conditioned by the micro-habitat differentiation and expressed through the variability of thickness of the genetic horizons for individual pedons, as well as spatial differences in acidity, moisture, conductivity, and organic carbon content. The studies were conducted on podzolic soils covered with forest vegetation. The results of studies carried out and described here indicate an influence of the local topo-habitat conditions on the spatial variability of soil properties. The following results can be drawn on the basis of the results obtained: 1) within the organic horizon the highest spatial differentiation of the properties considered was observed in the soils of Finland and Norway, while within the humus and enrichment horizons it was greater in the soils of the Polish part of the study area; 2) an exception to the above regularity is constituted by moisture; the highest spatial differentiation at this factor within all the genetic horizons was always observed in the soils characterised by its highest values; 3) spatial differentiation of the properties analysed is greater within the organic and humus horizons than in the enrichment horizon; 4) the biggest differences between the particular variants of the experiment, implemented during the four years of study, were displayed by: a) within the organic layer - the pedons of the northern and central parts of the study area, from Norway to Latvia, b) within the humus layer - the marginal pedons of FN1 and PL3, as well as the pedons of the central part of the study area - from Lithuania and Latvia, c) within the enrichment layer - the pedons of the Polish part of the study area; 5) interdependence was observed between the length of the micro-transects and the variability of the soil properties analysed; and 6) the strongest interrelation between the analysed properties were registered for the moisture - organic carbon content and moisture - conductivity.
7
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The morphological traits of needles as markers of geographical differentiation in European Pinus sylvestris populations

67%
Androsiuk P., Kaczmarek Z., Urbaniak L.
Dendrobiology
|
2011
|
tom 65
To evaluate the geographic variability of Pinus sylvestris populations seven morphological traits of needles of pines from IUFRO 1982 provenance trial have been analyzed. The studied populations originated from northern (>55°N in Russia, Sweden and Latvia), central (55-47°N in Poland, Germany, Belgium, France, Slovakia) andsouthern (<47°N in Hungary, Bosnia, Montenegro andTurkey) European ranges of Scots pine. The analyzedprovenance trial experimental areas were locatedin Kórnik (western Poland) andin Supraśl (north-eastern Poland). The greatest variation was found in needle length and number of stomata rows on the flat and convex side of a needle, whereas number of stomata per 2mmof needle length on flat and convex side of a needle was stable, with minor interpopulational variation. Biometrical analyses revealed a significant population × location interaction anda geographical pattern in interpopulational differentiation in both experimental sites, with the northern andsouthern European Scots pine groups of provenancesdiffering significantly from the group of central origin. The results obtainedare compatible with previous results of studies on provenance variability of the Scots pine from IUFRO 1982. In the light of available data, the influence of the Balkan glacial refugia of Pinus sylvestris on a present genetic diversity of this species in Europe and the reconstruction of Scots pine migration routes after the last glacial period are discussed.
8
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Zróżnicowanie geograficzne potrzeb deszczowania roślin w świetle symulacji bilansowej metody sterowania nawadnianiem w Polsce

67%
Manteuffel H.
Zeszyty Problemowe Postępów Nauk Rolniczych
|
1990
|
tom 387
Проведено сравнение средних оросительных норм, исчисленных путём компьютерного симулирования дождевания 17-ти культур и 2-х образцовых орошаемых севооборотов в течение 27 лет в условиях 11-ти географических пунктов в Польше. Выделены 3 зоны потребности ворошении.
9
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Temporal dynamics of the geographic differentiation of Late Devonian Palmatolepis assemblages in the Prototethys

67%
Girard C., Ta H. P., Savage N., Renaud S.
Acta Palaeontologica Polonica
|
2010
|
tom 55
|
nr 4
Throughout their history, species had to face environmental variations spatially and temporally. How both levels of variation interact will be of key importance in conditioning their response to major perturbations. We addressed this question by focusing on a period in Earth’s history marked by dramatic environmental and faunal changes, the Late Devonian Frasnian/Famennian boundary. From a paleogeographic point of view, this period is characterized by a cosmopolitanism of the faunas across a large ocean, the Prototethys. We considered the biotic reaction at a seldom considered scale, namely within a single subgenus of conodont, Palmatolepis (Manticolepis). Patterns of spatial and temporal differentiation were quantified using morphometrics of its platform element. The recognized cosmopolitanism of the faunas was confirmed at this scale of variation since temporal records gathered in distant areas around the Prototethys, including the seldom documented regions located nowadays in South−East Asia, displayed similar morphological trends in response to the major F/F crisis. Beyond this overall cosmopolitanism, subtle geographic structure was evidenced but was not stable through time. Geographic differentiation was maximal shortly before the F/F crisis, suggesting that despite high sea−level, tectonics leaded to complex submarine landscapes promoting differentiation. In contrast any geographic structure was swamped out after the crisis, possibly due to a global recolonization from few favorable patches.
10
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Content available

Geographical differentiation of Dryas octopetala in Europe based on morphological features

67%
Marcysiak K.
Dendrobiology
|
2014
|
tom 72
Dryas octopetala is an important arctic alpine species, but its morphological analyses are scarce. The study deals with present European biogeographical structure based on morphology and its relations to the phylogenetic structure and the climate. Characters of leaves from 23 isolated populations were measured, statistically characterized and analyzed with the use of ANOVA and the discriminant analysis. All the features differentiated the tested samples significantly. Differences between plants representing regions were greater than between the samples within regions with regard to the four characters. The most visible division ran between the samples coming from the southern and the northern parts of the range, with the sample from the Western Scandinavia occupying the central position. Correlations between characters and climactic factors were shown, and the size of the leaf was associated mainly with the minimum temperatures of spring months, while the leaf shape with the rainfall during the summer months. Characters differentiating the regions and discriminating populations strongly were mostly dependent on the influence of the climate. The results of the present study were not fully consistent with the outcomes of the biogeographic molecular analyses of the researched species. Some parallels can be drawn when comparing the present analyses with the geographic differentiation of two other arctic-alpine shrubs Salix herbacea and S. reticulata. Although morphological diversity of Dryas octopetala showed a geographic structure, it was most probably shaped mainly by the influence of the environmental and climatic factors.
11

Morpholithological genesis and soil properties of the pine forest ecosystems in relation to the North-South transect in Europe

67%
Degorski M.
Polish Journal of Ecology
|
2003
|
tom 51
|
nr 4
The influence of the geographically differentiated pedogenic factors on the properties of the podzolic soils of the pine forest ecosystems located along a meridional transect stretching between northern Finland (69°44′ N) to southern Poland (50°28′ N) was studied. The geographical trends in soil properties and the diagnostic soil features were determined. The results of many years of research on the spatial differentiation of the properties of podzolic soils confirmed the relations between the geographical differentiation of the pedogenic factors, the spatial variability of the structures of the soil cover, and the spatial variability of soil properties. In addition, an essential role of the soil in the functioning of boreal pine forest ecosystems was demonstrated. The following results can be drawn on the basis of the results obtained: 1) the spatial differentiation of the soil cover analysed is associated with the age of the original sedimentation, the texture properties of the substrate from which the pedons developed, the hygro-thermal properties of climate, and the structure of the vegetation cover; 2) along with the increase of the age of the soils towards south and the decrease of the humid character of climate the increase of the following parameters was noted: content of quartz and of the resistant minerals, the value of grain abrasion index (Wo), the value of the nonhomogenous index (Nm), the deficit of moisture, the thickness of the soil's solum, the ratio Ch:Cf, the degree of humification, the absolute content of the hydrogen ions, the contents of the bivalent cations in the sorption complex of the soils. The decrease was also noted of: the content of the non-resistant minerals, the value of the average grain diameter indicator (AGD), the thickness of the organic horizon (O), the storage of the organic carbon in the entire pedon, the content of the ammonia salts in the mineralised nitrogen, the saturation of the sorption complex of the soils with hydrogen cations, the total content of phosphorus and of the phosphorus accessible for plants, the value of the Schwertmann's indicator, and the value of the illuviation indicator after Mokma; 3) the highest ecological efficiency, as measured with the enzymatic activity, is displayed by the soils of the central part of the area considered.
12

Depauperated gene pools in Marmota m. marmota are caused by an ancient bottleneck: electrophoretic analysis of wild populations from Austria and Switzerland

67%
Preleuthner M., Pinsker W.
Acta Theriologica. Supplement
|
1993
|
tom 38
|
nr 2
Samples from 15 populations of the Alpine marmot Marmota m. marmota (Linnaeus, 1758) were surveyed electrophoretically for allozyme variation. Only 2 out of 50 enzyme loci showed polymorphism. Average heterozygosity was found to be low with 1.2%. No rare alleles were detected among the 8430 genes examined. The geographic variation at the two polymorphic loci (Pep-1 and Sod-1) was analysed in more detail. The distribution pattern of the allele frequencies indicates genetic differentiation between autochthonous and introduced populations. No striking deviations of the genotype distributions from Hardy-Weinberg equilibrium were observed. Thus the population structure is apparently not affected by inbreeding. The obviously diminished genetic variation and the geographic pattern of the allele frequencies at the two variable loci can be best explained by assuming a severe bottleneck in the recent past.
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