30 research outputs found
Morphological differentiation supports the genetic pattern of the geographic structure of Juniperus thurifera (Cupressaceae)
12 p., mapas, tablas, gráf.Juniperus thurifera is an important component of woodland communities of dry sites within the West Mediterranean region and is characterised by a strongly disjunctive geographic range. Two subspecies were recognised, subsp. thurifera in Europe and subsp. africana in Africa. The aim of the study was the comparison of phenetic diversity to the pattern of AFLP geographic differentiation of the species described in the literature. The examination of phenetic diversity was based on the biometrical analysis of 17 populations using 12 morphological characters of cone and seed. The differences among populations were analysed using Student’s t test, analysis of discrimination, UPGMA agglomeration and hierarchical analysis of variance. The majority of morphological characters differentiated at a statistically significant level between populations and between J. thurifera subsp. thurifera and subsp. africana. Three groups of populations were detected using multivariate statistical analyses. The first, well separated, is subsp. africana, while the following two concern subsp. thurifera. The morphological differentiation of populations appeared similar to that described on the AFLP. The Gibraltar Straight appeared to be the most important barrier.Funding the work was partly sponsored by the Institute of Dendrology of the Polish Academy of Sciences. The collection of material was made possible due to the bilateral cooperation of the Polish Academy of Sciences with the Spanish National Research Council "Consejo Superior de Investigaciones Científicas".Peer reviewe
Discovery of Juniperus sabina var. balkanensis R. P. Adams and A. N. Tashev in Macedonia, Bosnia-Herzegovina, Croatia and Central and Southern Italy and relictual polymorphisms found in nrDNA
Additional analyses of trnS-trnG and nrDNA from specimens from Bosnia-Herzegovina, southern and central, Italy, Croatia and Macedonia revealed the presence of J. sabina var. balkanensis in these areas west of the previously known populations in Greece, Bulgaria and western Turkey. Careful chromatogram analysis of eight (8) polymorphic sites in nrDNA revealed that nearly all of the populations of both var. balkanensis and var. sabina contained from 2 to 8 polymorphic sites. For these 8 heterozygous sites, two exclusive patterns were found in J. sabina. One type (GGACCCAG) was found in 16/62 plants and type 2 (ACGACAGT) was found in 4/62 plants. The majority of the plants examined (42/62) were heterozygous for 1 to 8 sites. These two nrDNA types appear to have arisen via hybridization with a J. thurifera ancestor. The two types appear in both v. sabina and v. balkanensis populations. Extant putative hybrids appear to have formed by crosses between present day type 1 and type 2 nrDNA. Publishe
Geographical differentiation of Dryas octopetala in Europe based on morphological features
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
Calculated characters of leaves are independent on environmental conditions in Salix herbacea (Salicaceae) and Betula nana (Betulaceae)
The goal of the study was to check if the shape-describing characters, calculated as ratios of the morphological measured traits are more stable, compared to the latter, and can be treated as independent on environmental conditions. The test was based on the example of leaves of Salix herbacea and Betula nana. The individuals of the two populations of S. herbacea from Tatra Mts. were divided into two groups: with bigger and smaller leaves. The two populations of B. nana came from different substrata: the first one, collected from the mire on the lower altitude, had bigger leaves, and the second, collected from the granite plateau and higher altitude, had smaller leaves.
For both species, the measured traits were generally more variable than the ratios calculated on their basis, as expressed by the variation coefficients. The results of Students' t-test analyses showed statistically significant differences between the two groups of S. herbacea and the two populations of B. nana with respect to almost all the measured characters, and no such differences for the calculated traits, reflecting the leaf shape.
As the differentiation of the leaf size was probably bound to the environmental factors, the lack of the dependence of the leaf shape on the leaf size could lead to a conclusion of independence of the leaf shape on the environment conditions
Interpopulational variability of Pinus uncinata Ramond ex DC. in Lam. & DC. (Pinaceae) cone characters
The characteristic of Pinus uncinata on the basis of biometrical analyses of 16 cone features was done. The research was based on 8 samples representing 6 populations, consisting of 50 cones each, collected in the Pyrenees, within the natural range of the species. All the investigated cone features were moderately differentiated, with the variation coefficient ranging from 8 to 30%. The particular populations differ significantly from each other statistically according to several features examined. The samples collected in the same population also vary significantly. The differences between populations, however, do not enable their division into groups, which supports their origination from the same Pleistocene refugia
Variation of cone characters in Pinus mugo (Pinaceae) populations in the Giant Mountains (Karkonosze, Sudetes)
The subalpine communities of Pinus mugo were destructed and replaced by pasture lands on plateau
parts and moderately inclined slopes of the mountains during between the 15th andthe 18th centuries. The
species were able to survive that pressure probably on the abrupt slopes of the glacial cirques. The pasturing
stoppedin the 19th century, andthe mountain pine startedto reforest its previous habitats since that time. It
was also plantedin several places andsome of contemporary populations can origin from the seeds of the
Giant Mountains. In the latter case the populations on the plateau shall reveal differences in the cone characters
from autochtonous ones from the glacial cirques. This study was structured on this hypothesis. The characteristics
of seven Pinus mugo populations in the Giant Mts. were comparedon the basis of 15 morphological
characters of cones. Each population was represented by at least 30 individuals, and for every individual 10
cones were examined. Four of the sampled populations, treated as local, occurred on the steep slopes of the
glacial cirques andthe other three on the mountain plateaus, usedas pastures in the 17th to 18th centuries, potentially
originatedfrom another region. Results show rather small differences among the comparedpopula -
tions, independently of origin. The separation of the plateau from the steep slope ones is rather inconspicuous,
if any. This suggests the local origin of plateau populations, even when planted
Variability of Pinus uliginosa cones from the peat-bog in Węgliniec
Cones of Pinus uliginosa from the "Torfowisko pod Węglińcem" reserve were tested biometrically, on the basis of 16 characters.The obtained data were statistically analysed.The cone scale width, the ratio of cone length/width and the maximal diameter of cone were the most stable, while the cone scale thickness and the ratio of cone scale length/thickness were the most variable of the cone characters.The intrapopulational differentiation was not big.The examined pine species has cones with characters which are intermediate between Pinus sylvestris, P. mugo and P. uncinata