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Six natural populations of sweet clover (Melilotus officinalis) were examined for allelic frequencies at 7 electrophoretically detected polymorphic loci in five enzyme systems: LAP, AP, ME, EST and PX. According to Nei’s statistics, the extent of genetic variability in all populations shows that intra-population genetic variability is expressed by higher values of GST coefficient (mean value for all loci 0.135) which exceeds values of inter-population differences expressed by DST=0.059 coefficient. Gene flow between populations is rather low (Nm=1.60). Hierarchical clustering (UPGMA) of Hedrick’s genetic distances (when examined simultaneously in all the allozymes), demonstrated three groups of populations suggesting certain tendency to geographic connections.
Provenance trials were designed to analyse the quantitative responses of tree species to environmental variables found in different experiment location. However, we have still limited knowledge how natural and artificial selection affects genetic variation of the species populations gather in such experimental sites. We have used bulked DNA-based RAPD and ISJ analysis to investigate genetic diversity and differentiation of Scots pine populations from two Polish locations of IUFRO 1982 provenance trial placed in Kórnik and in Supraśl. Applied categories of DNA markers differed in terms of revealing genetic diversity of the species. Ten RAPD primers applied in the study yielded a total of 75 bands, of which 21 (28%) and 15 (20%) were polymorphic in Kórnik and in Supraśl, respectively. Six ISJ primers revealed 42 bands of which 4 (9.52%) and 14 (33.3%) were polymorphic in Kórnik and in Supraśl, respectively. The genetic diversity and differentiation was low, as expressed by He=0.071 and He=0.085, and by genetic distance values which ranged from 0.0 to 0.240 (on average 0.081) and from 0.017 to 0.188 (on average 0.094) for Kórnik and Supraśl, respectively. Location of provenance trial appeared to have a significant influence on revealed level of genetic polymorphism and pattern of interpopulation differentiation. However, genetic structure found for analysed Scots pine provenances from IUFRO 1982 in Kórnik was also confirmed for Supraśl experimental site. In the light of available data we also discussed the influence of historical migration routes and gene flow on observed genetic variation of the species.
The reproduction ability of Primula veris L. plants was described on the basis of six-year observa­tions on permanent plots in populations from natural localities. Cowslip individuals in different life stages were mapped according to topographical distribution. The vegetative multiplication symptoms of the plants were also recorded. The mean survival rate of seedlings to the juvenile sta­ge was similar in both populations, amounting to about 16.5%. The highest survival rate was found for juveniles (44.3-57.6%) and immature (31.4-48.6%) individuals, while the lowest number of indi­viduals turned from the virginile into the generative stage (2.2-5.7%). The efficiency of the gene­rative reproduction measured by the ratio of the number of generatively recruited flowering plants to the observed number of seedlings was 0.22-0.42%, depending on the population.
Twelve morphometric variables of Cardaminopsis halleri individuals from four sites in upper silesia province were analyzed to establish the pattern of interpopulational relations. Two hundred plants were collected from two very polluted areas (near zinc-lead and zinc smelters) as well as from two other sites in unpolluted areas within the same bioclimatic region. stem size, dimensions of leaves and rosettes, as well as flower and seed numbers and in­dividual dry weights were studied using standard biometric methods. cluster analysis indicated overall differences among populations. Those four populations are different with respect to all variables. Discriminant function analysis confirmed seed number as the most important variable in the evaluation of interpopulational variability.
Small size of cabbage heads around 2.0 kg, preferred by the fresh market, may be attained by the choice of cultivar suitable for such purpose of production as well as culture practice, including reasonable rate of fertilization. The aim of the study was to evaluate the impact of increasing plant population combined with differentiated dose of nitrogen on yield of cabbage, its structure and plant composition. White head cabbage ‘Kalorama F1’ cv. was planted in rows 45 cm apart and 50, 40, 35 or 30 cm within rows, which assured 44 000, 55 000, 63 000 and 74 000 plants per 1 ha, respectively. Nitrogen at the rates of 150 or 300 kg ha-1 was used in 3 equal doses supplied as preplant and top dressing fertilization. Data obtained in the trial indicate that the dose of 150 kg N ha-1 was a limiting factor for the increment of crop yield in higher than 44 000 plant population per 1 ha. In the case of application the dose of 300 kg N ha-1 plants grown in population 63 000 and 74 000 per hectare produced significantly higher yield of heads if compared to the treatment with 44 000 plants. Taking into account the yield size and its structure it can be assumed that spacing 45 cm between plant rows and 40 cm distance in the row, which assure 55 000 plants per 1 ha is the optimum for production of cabbage heads weighted 1.0–2.0 kg, that meet the consumers expectation in the fresh market. Close plant spacing appeared to be beneficial for dry matter, vitamin C and total sugars contents and for decrease of nitrates accumulation. The enhancement of N dose to 300 kg N ha-1 was beneficial for total yield of heads as well those weighted > 1.0 kg. The only change in plant composition under influence of heavy N fertilization was the increment of nitrates accumulation and decrease of Ca content in cabbage heads.
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.
The research was conducted with a view to establishing physiological parameters of the silver fir (Abies alba Mill.) with regard to germination energy, absolute germination and genetic overload produced by silver fir populations. The intention was to identify significant variability within populations and subpopulations, or rather within the two combined, and to give recommendations on the usage and usability of seeds from specific populations. The results form a basis for establishing silver fir genetic overload within five fir populations of central Bosnia and Herzegovina. The results of research on the characteristics such as absolute seed weight, germination energy and absolute germination are within a scope of previous studies. The studied physiological characteristics of silver fir seeds in the central Bosnia area showed distinct individual and inter-population variability when compared to variability of the subpopulations analyzed. The inclusion of non-physiological data (height, DBH, age and the presence of mistletoe) concerning sampled trees proved to be effective new quality of research. No correlation was found between DBH and seed physiological characteristics but increased tree height had a positive effect on seed quality in terms of absolute germination and growth, proportional to tree height. This in turn shows that seeds should be collected only from trees of above average height, because they are less genetically overloaded. The characteristics of healthy but ungerminated seeds from less tall trees displayed lower parameter values, also indicating that seeds should be collected from taller than average trees only. The presence of mistletoe had a very interesting effect of increasing rotten seeds percentage, and therefore reducing seed quality. Accordingly, seed collection should be limited to trees not affected by mistletoe, however further research on this aspect is required.
Two localities for Huperzia selago subsp. arctica are recorded from Lithuania, to the south of its known distribution area. The habitats of this subspecies are cutover peatlands whose natural vegetation was disturbed 6-8 years ago during peat exploitation. One of the dominant species of latest vegetation cover is the invasive bryophyte Campylopus introflexus. Characteristics of the habitats of H. selago subsp. arctica and the frequency of this taxon in populations were analysed.
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.
Fraxinus angustifolia Vahl is a species native in the north-western Balkans, where it has a divided range. Most of its range is located in flood-prone riparian sites in the Pannonian plain but the species is also found on humid sites along some rivers in the Submediterranean region. We analysed morphologic variation within and between five populations (14 trees/population) located in the Subpannonian and Submediterranean region of Slovenia. Thirty two characters were assessed on ca. 80 leaves from each tree which were divided depending on exposure to sunlight (sun and shade leaves), and 8 traits on each fruit (ca. 50 fruits/tree). A hierarchically designed experiment using analysis of variance confirmed the significant contribution of all the analysed hierarchical levels of variation to the total variation. The results show that the differences between the trees in a single population are the greatest factor of variability of leaves, followed by differences between populations and differences which are the result of variation in exposure to sunlight. Leaves in shade positions are typically larger than those in sunny positions, and they have broader and shorter-pointed leaflets; in this feature they are very similar to the leaves of F. excelsior. Stepwise discriminant analysis showed that the traits which refer to the leaflet number and length are the best differentiating traits between individual populations. The Submediterranean population Dragonja stands out with the smallest leaves and the population Lijak from the same region is the most similar to Dragonja for most morphological traits. In general, phenotypic differences between the Subpannonian and the Submediterranean populations of F. angustifolia are minor and indistinct. Based on the differences ascertained by the study, we can only confirm the presence of F. angustifolia subsp. oxycarpa (Bieb. ex Willd.) Franco et Rocha Alfonso in this part of its natural range.
The genetic Variation of Reed Grass Calamagrostis arundinacea (L.) Roth was investigated in 25 populations in various geographic regions of Poland. A total of 907 individuals were sampled for electrophoretic analysis of peroxidase loci (11 allozymes). Populations were characterised by genetic parameters e.g. heterozygosity level, Wright's fixation index (F) and polymorphism coefficient (Pg). Mean values of interpopulation variability level (GST=0.0310), total genetic diversity (HT=0.4102) and gene flow between populations (Nm=7.805) were also examined. All the populations were polymorphic and they remain in Hardy Weinberg equilibrium.
Differences between 13 common reed (Phragmites australis) populations, growing in urban conditions within the town of Poznań (western Poland), are described by 8 morphological traits of panicles' variability and the frequency of peroxidase (dimeric and monomeric) allozymes. Values of morphological characters were processed statistically using agglomerative clustering by the closest neighbours (UPGMA) method based on Euclidean distances. Proteins were separated in the starch gel electrophoretic procedure, showing cathodic migration. Populations are polymorphic and have a certain level of heterozygosity. The level of populations' diversity (DST = 0.097) is lower than the intra-population variability (GST = 0.187). The gene flow between populations is rather low (Nm = 1.090).
The genus Eulophia embraces over 230 species distributed through the tropical and subtropical Africa, Asia, Australia and the Americas. In Neotropics it is represented by a sole species – E. alta. The aim of the presented study was to evaluate the difference between ecological niches occupied by American and African populations of this species based on the ecological niche modeling. The similarity between the glacial and present niches occupied by E. alta was calculated and the factors limiting the species occurrence were identified. Areas of seasonal tropical forest, tropical savanna and woodland served as refugia for the studied species during last glacial maximum and they were more widespread in Neotropics than in Africa. No significant niche shift after last glacial maximum was observed. The distribution of E. alta in its whole range is restricted mainly by temperature seasonality. The differences in the niches occupied by African and Neotropical populations of E. alta suggest preglacial disjunction of the species range and independent adaptation of both groups. Despite the significant range disjunction of E. alta the species is characterized by relatively high degree of niche conservatism.
In the area of the western Balkans, xerothermal broad-leaf forests hold a very special position, the main species being pubescent oak (Quercus pubescens Willd.). The study comprises 36 populations of pubescent oak from Croatia, Bosnia and Herzegovina, Montenegro, Kosovo, Albania and Macedonia. Genetic variability and population diversity was analysed on chloroplast DNA in order to determine to which haplotype an individual or studied population belongs, as well as how they are related. For the detection of one haplotype analysed four sequences (AS, TF, DT and CD) on the chloroplasts DNA. The results of the analysis suggest that there are six different haplotypes of pubescent oak (2, 4, 5, 17, 31, 33) in the studied populations. Two more sub-haplotypes were found in haplotype 5 (a and b), but only in populations occurring in Croatia and Bosnia and Herzegovina. The results suggest the great variability of pubescent oak in the researched area, which is generally characteristic of other species from the area of the Balkan Peninsula. The results obtained by means of cpDNA analysis can help in the formation of seed zones. However, due to the strong selection pressure of unplanned logging, and the possible introduction of herbal material of unknown origin, it is necessary to find a sufficient number of autochthonous entities (i.e., populations of the researched species) as well as new suitable markers for their characterization. The results of this paper constitute a scientifically recognised, partial examination of the origin of the starting forest reproductive material from the broader geographic area, thus serving future projects on its regeneration.
Three elm species are native to Poland: wych elm (Scots elm) (Ulmus glabra Huds.), field elm (U. minor Mill.), and European white elm (fluttering elm) (U. laevis Pall.). The epidemic of Dutch elm disease (DED) has led to a decrease in the popularity of elm cultivation. An analysis of forestry data was the first step in the assessment of elm resources. The area of forest stands where elms are dominant has more than doubled since 1978. Lowland alluvial forests rank first in regards to the number of elm localities per unit area of a given forest site type. While this site type is clearly preferred by elms, the majority of elm trees are actually scattered among sites of oak-hornbeam or closely related forests (of the alliance Carpinion betuli). Field research revealed a clear dominance of U. laevis, a species which in the past was predominantly located out of woodland and rarely cultivated. Data analysis indicated that all trees greater than 70 cm in diameter belonged to this species. Data from plots surveyed directly also suggest that the three elm species have slightly different habitat preferences. U. laevis prefers riparian habitats, although the major part of its resources is now on potential sites of oak-hornbeam or closely related forests. U. minor even more often than U. laevis occurs at less humid sites (mostly potential sites of oak-hornbeam or closely related forests), while U. glabra prefers moist slopes. In general, it appears that the impact of DED in the last 20–30 years has been smaller than in the preceding period, however, the disappearance of the disease has not been established. Undoubtedly, U. laevis is the elm species that is least impacted by DED
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