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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.
This paper presents the genetic variability in the growth parameters and morphological traits, as well as the silvicultural quality of progeny of 23 European beech (Fagus sylvatica L.) provenances from south−eastern Poland. The research was conducted on the experimental plot established in the Łosie Forest District in spring 2006. After 10 years, during the spring and autumn, we determined and measured the spring phenology and survival rate, the diameter at breast height (dbh), the tree height, and the straightness of trunk. The results obtained point out the considerable variability of analysed features, both within and between different beech populations (tab.). Highest and lowest survival rates are noted for the beeches from Lutowiska and Leżajsk (populations 451 and 461), respectively (fig. 2). Lowest mean height and dbh were achieved by beeches from Bircza (453), while the tallest and broadest trees were from the Kielce population (390) (fig. 3−4). The overall silvicultural assessment based on survival, height, dbh, spring phenological phases and straightness of the trunk revealed that the most valuable populations of beech are those originating from Kielce (390), Bircza (454), Strzyżów (459), Lesko (452), Rymanów (457) and Lutowiska (451). In turn, the analysis resulted in least favourable assessments for beeches from Bircza (453) and Gromnik (362). Thus, we confirmed also that trees of local origin are not always best−adapted to (and do not always grow best in) the place they originate from. The obtained results are highly relevant from the principles of creating the seed source regions for beech in Poland, as the proper selection of a population for the given place of growth may yield benefits for forest ecology and management.
European beech is one of the most important broadleaved tree species in Poland and will play probably even more significant role in the future due to the predicted climate change. The main objectives of this study was to analyse and compare the growth parameters and morphological traits between 23 European beech provenances from south−eastern Poland (fig. 1). The research was conducted on the experimental plot established in Łosie Forest District in 2006. The experiment employed a randomized complete block design consisting of 92 plots (23 provenances×4 blocks). On each plot 100 trees representing given provenance were planted in 1.5×1.5 m spacing. In the spring and autumn 2015 we measured and determined the following parameters for the subsample of 36 trees on each plot: survival rate, tree height, diameter at breast height, diameter of the branch at the middle height of the crown length, stem straightness, crown shape, tendency to create forks, mean angle between stem and branches and spring phenology. We also included different eco−physiographical characteristics for each provenances (tab. 1). We performed basic statistics to describe mean values and standard errors (fig. 2, tab. 2) and finally we quantified the interaction between traits and eco−physiographical characteristics by Principal Component Analysis (PCA) (fig 3, tab. 3). The obtained results indicates that under growth conditions on experimental trial in Łosie Forest District, the provenances from lower elevated regions with lower precipitation and higher mean temperature (i.e. more arid conditions; Kielce and Narol provenances) were characterized by thicker dbh and branch dimeters in contrast to regions from southern Poland (Łosie, Bricza 1, Stary Sącz and Nawojowa). European beech provenances from regions with more humid conditions and lower mean annual temperature, as well as shorter vegetation season are characterized by higher survival rate. They are also higher than other provenances, but reveal the lower ratio dbh to branch diameter.
The genetic variability of sessile oak (Quercus petraea L.) mature stand and its natural progeny was investigated. Comparison between genetic structure of parental and progeny trees was based on frequencies of nuclear microsatellite (SSR) alleles occurring in three DNA loci. A slight (4%) increase of gene pool between oak mature and progeny trees was revealed by heterozygosity level estimation, maintaining 86.3% of genetic similarity between generations. Also allele richness, partition probability of basic clustering and inbreed coefficient proved the high genetic similarity between parental and progeny of investigated oak trees. The gene flow occurred within the stands as far as rare alleles were transmitted or new ones appeared in the progenies. The results highlight the necessity of such a study for silvicultural measures taken in order to proceed natural or artificial regeneration in forest tree stand.
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