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In forestry management, artificially produced planting material is mainly used for renewal the tree population. Seedlings are cultivated in two systems: in the ground (the bare−root seedlings) and in controlled conditions (container seedlings). The aim of the study was to analyse the microsatellite markers of nuclear and chloroplast DNA, in terms of the number and frequency of rare, private, low frequency and common alleles in the planting material of Scots pine. The rare alleles included alleles occurring with less than 1% in analyzed group of seedlings and low frequency alleles occurred with a frequency of less than 25%. The private alleles were detected only in one group of seedlings. Genetic pools of seedlings from traditional (soil) and container production were compared. Planting material came from nurseries in the Olsztynek (N Poland) and the Oleszyce (S Poland) forest district. With the similar number of observed nDNA and cpDNA alleles in both analyzed locations, a higher number of rare, low frequency and private alleles was found within container seedlings. Most private alleles were a rare allele. Rare and private alleles are supposed to be responsible for adaptation to changing climatic conditions and a stressful environment. It seems reasonable to continue research on the meaning of rare and private alleles under conditions of strong selective pressure.
The production of forest tree species in forest nurseries is performed via two main breeding systems: i) the traditional (conventional) way with the seedlings grown in soil, and ii) plants cultivated in the containers. The aim of the study was to assess the level of genetic variability in the populations of the mother stands and the progeny populations of Scots pine cultured with traditional way (in soil) and in containers in two nurseries in Olsztynek (N Poland) and Oleszyce (S Poland) forest districts. Four polymorphic microsatellite markers (SPAG 7.14, SPAC 11.6, SPAC 12.5 and SsrPt_ctg4363) were used to evaluate the genetic variability of the studied populations. The basic hypothesis assumed that higher gene pool characterizes the seedlings grown in the containers comparing to the seedlings grown in the ground. The results confirmed that. Seedlings from containerized breeding had larger gene pool and were more diverse than plants with conventional breeding, both in Olsztynek and Oleszyce. Our study revealed a significant human impact on shaping the pool of forest genetic resources of Polish forests at the early stage of nursery production and showed the need for a broader study on further stages of cultivation of forests.
The programme of testing the progeny of permanent seed stands, parent trees, seed orchards and seedling seed orchards that has been run in Poland enables to determine the genetic value and silvicultural quality of the progeny of components of primary forest material. A better knowledge of population variability and adaptability to particular environmental conditions also allows for the updating and verification of principles regarding the use of the seed base in testing regions, as well as the determination of possibility for forest reproductive material to be transferred. The article presents the research on assessment of survival and growth among progeny from 26 permanent seed stands of silver fir that originates from Lublin, Radom and Łódź Regional Directorates of the State Forests, at four testing grounds located in the Kielce, Suchedniów, Tomaszów and Zwierzyniec forest districts. Each research plot was founded with 4 replicates, each with 3−year−old saplings. After 5 years of growth, mean rates of survival ranged from 70.4% at the Kielce site to 92.7% in Tomaszów. The lowest survival rate (30.5%) was noted for local origin (Starachowice), while the highest (93.8%) characterised the local standard from Zwierzyniec. Mean height varied from 54.1 cm in the case of the Suchedniów to 80.0 cm in the case of Tomaszów, albeit with the shortest firs originating from the Starachowice local standard and the tallest from the Tomaszów local standard. Analysis of variance components revealed that the environmental conditions (described by study area) played major role in shaping the variability. This effect was responsible for around 75% of the variance in height and 60% of that relating to survival. In contrast, origin (genetic factor) was most likely responsible for 7% of the noted variance in height or 4% of that relating to survival.
Considered to be the most natural of all other Polish stands Picea abies in Białowieża Forest has suffered severely of bark beetle damages for decades. In order to find out some historical events in native Norway spruce stands diversity at regional level, we carried out the study on polymorphism with DNA markers and performed Principal Coordinate Analysis (PCoA) on the basis of genetic distance matrix. Two ranges (i.e. Baltico−Nordic and Hercyno−Carpathian) of Norway spruce cover north−eastern and southern Poland, respectively. The spruceless zone separates the these two ranges in lowland Poland. From genetic point of view, the Baltico−Nordic P. abies populations mainly harbor mitochondrial haplotype ‘c', whereas the spruces from the Hercyno−Carpathian range – haplotype ‘a'. Until recently, the Białowieża Forest has been considered to belong to the northern range of spruce occurrence in Europe. Seven populations from Białowieża Forest were studied (two of them from the Strict Reserve in Białowieski National Park) according to mitochondrial DNA diversity, and compared with genetic diversity found in 24 other populations located in Białystok Regional Directorate of the State Forests (north−eastern Poland). All studied spruce populations were more than 100 years old and were of natural origin. As result, the spruces from the Białowieża Forest harbored three mitochondrial haplotypes of the nad1 gene (‘c', ‘a' and ‘a1'), with the haplotype ‘a' being more frequently present (>51%) than the haplotype ‘c'. The spruce stands from Białowieża Forest have the highest gene diversity (h Nei=0.527) comparing to the other stands from the Białystok RDSF. The PCoA proved the particularity of the spruces from Białowieża Forest grouping them into one cluster of genetic similarity. Our data demonstrated that most of Norway spruces populations from Białystok RDSF harbor haplotype ‘c', which confirms their historical relationship with the Baltico−Nordic range of P. abies in Europe, while most spruces from Białowieża Forest have different historic origin, because they share high frequency of the southern haplotype ‘a'. It also turned out that Norway spruce populations from two different European ranges met in lowland Poland after the last glacial period, as proved by the presence of two mitochondrial haplotypes ‘a' and ‘c'. It can be assumed, that the spruceless zone was created by human activity in the past millennia. The results of all molecular analyses confirmed the unique character of spruces of Białowieża Forest, which is distinguished by the greater richness of the gene pool in comparison to the region of Białystok RDSF as well as good adaptation to local environmental conditions.
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