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Pollen grains of Pinus uliginosa and P. uncinata were examined by light and scanning electron microscopy. The pollen grains were bisaccate and monosulcate. The corpus-saccus attachment was distinct. The pollen corpus exine sculpture was verrucate-rugulate and deeply sculptured. The surface of the tectum was with or without small grana and it was perforate. The saccus sexine ornamentation was reticulate and irregularly perforate. The tectum surface characters in the proximal and distal view of the corpus and saccus were less variable and they did not provide good criteria to identify the species under study. Among the P. uncinata from the Forest Arboretum there were differences observed in the size, shape and height of elevation and sculpture on the corpus between pollen grains of the same specimen. This study of the pollen grain morphology of the corpus and saccus provided some important new data.
Recent changes in environmental conditions in populations of peat-bog pine (Pinus uliginosa Neumann) caused rapid decline or even extinction of the species in several stands in Central Europe. Conservation strategies for P. uliginosa require information about the evolutionary history and genetic structure of its populations. Using isozymes we assessed the genetic structure of P. uliginosa from four isolated stands in Poland and compared the results to genetic structures of other closely related pine species including eight populations of Pinus mugo, ten of Pinus sylvestris and one of Pinus uncinata. The level of genetic variability of P. uliginosa measured by the mean number of alleles per locus and average heterozygosity was similar to others related to P. uliginosa taxa from the reference group but it differs among populations. High genetic similarity was found between two populations of P. uliginosa from Low Silesian Pinewood. The populations were genetically distinct as compared to other populations including locus classicus of the species from the peat bog at Batorów Reserve. Very low genetic distance (DN = 0.002) and small genetic differentiation (GST = 0.003) were found between P. uliginosa and P. mugo in the sympatrie populations of the species from Zieleniec peat bog suggesting the ongoing natural hybridisation and genetic contamination of peat-bog pine from this area. Some evidence for skew in allele frequency distribution potentially due to recent bottleneck was found in population from Low Silesian Pinewood. The analysed open pollinated progeny derived from two P. uliginosa stands from Low Silesian Pine- wood showed the excess of homozygotes as compared to the maternal trees indicating high level of inbreeding (F =0.105,F = 0.081). The results are discussed in the context of evolution of P. uliginosa populations, taxonomie relationships between the analysed species and conservation strategies for active protection of peat-bog pine.
Genetic differences between two populations of P. uliginosa from Batorów and Węgliniec were assessed on the basis of 15 allozyme loci. The level of genetic differentiation between them was also compared with genetic differences among the three closely related pine taxa: P. uliginosa, P. sylvestris and P. mugo. A high level of genetic variation was found in both populations of P. uliginosa. The average (Na) and effective (Ne) numbers of alleles per locus amounted respectively to 2.47 and 1.50 in Węgliniec and to 2.67 and 1.52 in Batorów and the percentage of polymorphic loci was 80% and 87%, respectively. Close relationship between the three studied species were confirmed. The genetic differences between the two populations of P. uliginosa were substantial, as the Nei's genetic distance between the two populations (D = 0.040) was larger than between populations of P. sylvestris and between populations of P. mugo. The relatively high level of genetic differentiation between P. uliginosa populations may result from their isolation, small size and possibly different origin of these populations.
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.
Peat-bog pine Pinus uliginosa Neumann has become extinct or rare in many parts of Europe. We have investigated the levels of genetic variation and inbreeding in seeds collected from a highly endangered reserve of this species in Poland, using allozymes as genetic markers. Generally, a high level of genetic variation was observed. The mean expected heterozygosity was 0.376, while average (Na) and effective (Ne) numbers of alleles per locus were 2.45 and 1.67, respectively. Nevertheless, we have detected relatively low levels of outcrossing, and potential biparental inbreeding. The population-wide multilocus outcrossing rate was estimated to be 0.706 (±0.091), while the minimum variance mean of single-locus estimates was distinctly lower (ts=0.611). The estimates of outcrossing calculated for individual trees ranged widely from 0.051 to 1.017, indicating the complexity of outcrossing patterns. The investigated population of P. uliginasa from Węgliniec is small and surrounded by extensive forest stands of P. sylvestris. Our three-year records of phenological observations demonstrated that flowering periods for P. uliginosa and P. sylvestris overlap, allowing for cross-pollination. The possibility of P. uliginosa pollination by P. sylvestris creates a potential danger of genetic erosion of the P. uliginosa gene pool. Nonetheless, based on a species specific cpDNA marker we have found that among 533 seedlings of P. uliginosa there were only six seedlings carrying cpDNA marker specific for P. sylvestris, indicating that such hybridization seems to be rare.
The results of morphological and anatomical studies on Pinus uliginosa needles from newly-discovered localities of this species in Węglowiec (Bory Dolnośląskie) are presented. The data obtained were compared to similar published material on P. uliginosa needles from its loco classico in Batorow and from the lowland locality in Węgliniec Nature Reserve, and to P. sylvestris growing nearby. In terms of needle structure, all three P. uliginosa populations were slightly different. The samples analyzed differed markedly from the sample of P. sylvestris, which contradicts the hypothesis that Scots pine has had a significant influence on the gene pool of P. uliginosa.
Pinus uliginosa is an interesting taxon from the Pinus mugo complex with controversial systematic position andspecific characteristics, intermediate among P. mugo, P. uncinata and P. sylvestris. The peat-bog pine is rare andprotectedin Poland. All its’ known populations have a relict character andare slightly different from each other. The aim of the present study was comparison of the individuals from the Czarne Bagno of the “Torfowisko pod Zieleńcem” Nature Reserve (Sudetes), determined in the field on the basis of morphological characteristics as Pinus uliginosa, with four samples of this taxon from the northern limits of its range in PolandandGer - many andwith Pinus sylvestris, P. mugo and P. uncinata, to verify morphological andtaxonomic relations between them. The material collected from 30 individuals determined as P. uliginosa, was closest to populations of P. uliginosa from the Bory Dolnośląskie, andto P. mugo from the Tatra Mts., concerning the needle characters. The cone characteristics of P. uliginosa individuals from the Czarne Bagno appeared similar to all other of that taxon. In spite of that, the cone characters first of all differentiate P. uliginosa from P. sylvestris, P. mugo and P. uncinata. The combination of needle and cone morphological characters are a good tool to distinguish P. sylvestris, P. uncinata, P. mugo and P. uliginosa with a very high probability.
Pinus mugo complex (Pinaceae) – taxonomic relations based on needle characters. Fragmenta Floristica et Geobotanica Polonica 11(2): 235–255. Kraków. PL ISSN 1640-629X. ABSTRACT: The relations between Pinus mugo, P. uncinata and P. uliginosa [=P. ×rotundata], which form Pinus mugo complex, were examined biometrically on the basis of morphologic and anatomic characters of needles. All these taxa are statistically significantly different in respect of most of the 15 characters studied from compared P. sylvestris. In spite of close relations among P. mugo, P. uncinata and P. uliginosa, several morphologic and anatomic characters of needles discriminated them statistically significantly. The results suggest that P. mugo and P. uncinata should be treated as independent species, not as subspecies of P. mugo sensu lato. The intermediate position of P. uliginosa between two latter taxa suggests its hybrid origin.
The taxonomic position of the population of tree-like, mostly polycormic individuals of pines from the Mshana peat bog in the Gorgany Mountains (East Carpathians, Ukraine) has been studied on the basis of the morphological characteristics of cones and needles, and anatomical characteristics of the needles. These features have been compared with the surrounding Pinus mugo population as well as P. uliginosa, P. mugo, P. sylvestris and P. uncinata from natural populations of the taxa. Tree-like individuals were found to have the most similar needles to P. uliginosa, but most similar cone characteristics to P. mugo. It was concluded, that the tree-like population has a relic character and can present the trace of the early migration of P. uliginosa from the West and its hybridisation with P. mugo.
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