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State Forests, sharing the responsibility for preservation of natural and cultural heritage, conduced to successive undertaking of coming into existence one of the most modern plant gene bank in Europe. It is located in the immediate vicinity of ecological disaster which occurred in the Western Sudeten and Karkonosze Mountains. The mission of protecting and preserving the gene resources of dying-out tree populations of Sudeten provenance of silver fir, common spruce or European larch, was charged to Forest Gene Bank (FGB) with the task by General Director of State Forests. Soon the mission was broaden to the whole country when the FGB was included into Programme of forest gene resources protection and selection breeding in years 1991-2010@. The aims of the Programme are collecting and preservation of forest gene resources of all woody plants species both in situ as progeny plantations and gene conservation plantations and ex situ as living gene banks called clone archives, seed orchards and half-sib seed orchards but also the aims concentrate on gathering the most valuable gene resources of both, single trees and shrubs and the populations of trees in gene banks. Long-term storage of seeds and other parts of plants is performed by traditional methods in low temperatures and liquid nitrogen. 5077 gene resources are stored in FGB including both, the populations and single trees. A great challenge for the FGB is also trying to preserve the other plants (including the ones from areas not administered by the State Forests) and especially seeds and other parts of plants of Recalcitrant type and other woody plants, shrubs and herbaceous plants shown in the Red Book and on the areas of NATURA 2000.
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Field elm (Ulmus minor Mill.) is distributed mainly across central and southern Europe. In Poland this species occurs in the lowlands and foothills, where it grows mainly in the floodplain forests along the rivers. U. minor exists in a variety of climatic and ecological conditions. It is capable to tolerate floods as well as drought. Currently, most populations of U. minor are small and fragmented resulting from human activity and Dutch elm disease. Moreover, in the natural field elm populations, vegetative propagation by root suckers or sprouting can be observed. All these factors may affect the level of genetic variation of U. minor populations in Poland. In the present study, we determined the level of genetic variation and the clonal diversity of twelve natural U. minor populations in Poland (407 individuals) using eight nuclear microsatellite loci. The obtained results indicate that the studied field elm populations are characterized by low level of genetic variation (He=0.382; Ho=0.555; A=7.0). Additionally, the high level of clonality in field elm populations was estimated. The clonality level of examined elm populations varied among them, and in some cases was very high. Out of the 407 individuals analysed for clonal structure only 61 multilocus genotypes were identified. Furthermore, only one genotype was identified in the three study populations of field elm, which means that in each of these populations all trees belong to one genet. The values of genotypic richness (R) were heterogeneous among populations, with mean 0.148. The knowledge on the genetic diversity and the clonal structure of U. minor populations is essential to make future decisions regarding conservation of genetic resources of this species in Poland.
Wych elm (Ulmus glabra Huds.) is a rare scattered forest tree species in Poland. First studies on genetic diversity of the species in its natural range in Poland give a good basis for the management and conservation of its genetic resources. In the present study, we determined the level of genetic variation and genetic differentiation of seventeen natural Wych elm populations in Poland using nine nuclear microsatellite loci. The number of analyzed individuals was 601. The level of genetic diversity of Polish populations of Wych elm corresponded with the results of the previous studies on this species in Europe. The populations show quite low level of genetic diversity of the species on the population level and quite high diversity on the interpopulation level. A total of 119 alleles was found, with average number per locus (A) equal 6.0 and allelic richness at medium high level (AR10=4.7). Observed (Ho) and expected (He) heterozygosity reached 0.583 and 0.602 respectively. The genetic differentiation between Polish populations of Wych elm occurred at a low level (Fst=0.089). Inbreeding depression may occur in the next generations (Fis=0.031). Genetic diversity between Wych elm populations in Poland may be the result of unfavorable random processes related to the reduction of population size resulting from elm disease. To better understand the processes related to the genetic diversity of Wych elm populations, research on field elm variation should be undertaken. Such studies may give an answer to the potential influence of introgression between these species on the genetic structure of the Wych elm. Both in situ as well as ex situ conservation measures are highly recommended to preserve genetic resources of this valuable noble hardwood species in Polish landscape.
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