Populations located at the periphery of the species’ distribution range may play an important role in the context of climate change. These peripheral populations may contain specific adaptations as a ...result of extreme environmental conditions. The aim of this paper was to assess within population genetic diversity and among population differentiation in one of the most important forest tree species in Europe, European beech (Fagus sylvatica), at the eastern margins of its natural range. We analysed four peripheral, isolated populations and five core populations from the continuous natural range along the Carpathian Mountains using a set of microsatellite markers. Higher levels of genetic diversity as measured by allelic richness (7.34 vs. 6.50) and observed heterozygosity (0.71 vs. 0.59) were detected in core populations than in peripheral ones. Population differentiation was slightly higher among peripheral populations than among core, Carpathian populations. There was strong evidence of bottleneck effects in two out of the four peripheral, isolated populations. Both core, Carpathian populations and peripheral, lowlands populations share the same chloroplast haplotype suggesting a common geographical origin from the putative Moravian refuge area. Past long distance founding events with material from the Carpathian mountain chain might explain the occurrence of small, isolated beech populations towards the steppe in the south-east of Romania. Our genetic data may contribute to a better understanding of the evolutionary history of the remnants of beech scattered occurrences at the eastern margins of species’ distribution range.
Patterns of fine-scale spatial distribution of multilocus genotypes can provide valuable insights into the biology of forest tree species. Here we tested for the existence of spatial genetic ...structure (SGS) in a four-oak-species forest with contrasting species abundances and hybridization rates. A total of 483 adult trees were mapped over 8.6 ha and genotyped using 10 highly polymorphic genomic regions. A weak but significant SGS was observed in each of the four oak species, with Quercus frainetto, the species with the lowest density in the sampling plot, exhibiting the strongest SGS. The values of the Sp statistic were 0.0033, 0.0035, 0.0042, and 0.0098 for Q. petraea, Q. robur, Q. pubescens, and Q. frainetto, respectively. The spatial correlogram of the total population was significantly different when hybrids were removed from the analysis, which suggests that hybridization influenced the SGS. Interspecific SGSs were significantly correlated with the rates of hybridization. Implications of the obtained results for the conservation and management of forest genetic resources are discussed.
The performance of 33 Norway spruce Picea abies (L.) Karst. seed sources from the Romanian Carpathians was evaluated with respect to growth and wood characteristics in comparative trials located at ...two different site conditions: Avrig- outside of the natural range of Norway spruce and Bret¸cu - within the natural range of this species. The radial increment (RI), latewood percentage (LWP) and conventional wood density (CWD) traits were evaluated at age 30 years after plantation. Phenotypic correlations between the evaluated traits, on the one hand, and between the same traits and the geographic gradients of the origin of seed sources, on the other hand, were calculated. Analysis of variance showed significant (p<0.01) differences between seed sources for RI, while for LWP and CWD, the differences were highly significant (p<0.001). These results suggest that selection at seed sources level could be possible. The test sites influence the LWP and CWD, while the RI is almost similar in both sites. For RI, the most valuable populations are situated in the Eastern and Western Romanian Carpathians. The highest LWP was registered for the Eastern Carpathian populations, while the lowest was recorded for the Western Carpathian populations. The Southern Carpathian populations, characterized by a lower growth rate, had higher values for wood density.
Genetic diversity is very important to species evolution in changing environments. The aim of this study is to review the work done on genetic diversity of Romanian populations of beech, estimated ...mainly with genetic markers. Only a few studies have been conducted so far on Romanian beech populations. A large scale cpDNA study revealed that the populations of beech from the Romanian Carpathians have their origin in Moravian population. Several isolated populations have not been analyzed so far and could bring new data about the evolutionary history of this species. Due to the increase of temperature in the south-eastern Romania marginal populations of beech are currently growing under extreme conditions. A comparative study between core and marginal populations could bring new insights into the adaptation of beech to dry conditions.
Growth traits and survival rate were evaluated in two field trialsconsisting of 33 provenances (seed stands) spread across the entire natural distribution range of Norway spruce in Romania. Total ...tree height, diameter at breast height (DBH) and survival rate were measured at 30 years after planting. Both growth and adaptation traits show substantial genetic variation among the tested seed stands. The amplitude of variation depends markedly on trait and testing site. This fact suggests that the best performing seed stands for growth and adaptation traits at each testing site can be selected. Two groups of valuable populations from Romanian Carpathians - the Northern and Western part (Apuseni Mountains) - were identified. Survival rate was negatively correlated with growth traits, the average values in the two field trials were 68% and 70%. By analyzing growth and adaptation traits together with stem and wood qualitative traits, the best performing populations will be considered as tested seed sourcesand the forest reproductive material they can provide will be recommended for use in the regions of provenance where the two field trials are located.
Growth traits and survival rate were evaluated in two field trials consisting of 33 provenances (seed stands) spread across the entire natural distribution range of Norway spruce in Romania. Total ...tree height, diameter at breast height (DBH) and survival rate were measured at 30 years after planting. Both growth and adaptation traits show substantial genetic variation among the tested seed stands. The amplitude of variation depends markedly on trait and testing site. This fact suggests that the best performing seed stands for growth and adaptation traits at each testing site can be selected. Two groups of valuable populations, located in the North and East of Eastern Carpathians (Apuseni Mountains), were identified. Survival rate was negatively correlated with growth traits, the average values in the two field trials were 68% and 70%. By analyzing growth and adaptation traits together with stem and wood qualitative traits, the best performing populations will be considered as tested seed sources and the forest reproductive material they can provide will be recommended for use in the regions of provenance where the two field trials are located.
Adult bear individuals live solitary and haveprolonged parent-offspring relationships, therefore the share of learned skills compared to the inherited ones is much larger than in other carnivores. ...This promotes acquisition of deviated behavior and simultaneously establishment of a kinship structure. However, deviated bear behavior and human food conditioning are the symptoms of habituation. The aim of this paper is to test the genetic structuring of habituated and non-habituated individuals located in the central region of Romania (Brasov and Prahova districts), a hotspot in terms of human-bear conflicts. Seven microsatellites were used to genotype 145 samples (ear clips and tissue), out of which 82 were classified as habituated and 63 as wild individuals, respectively. Our results suggest the presence of kinship structures in habituated bear group and a reduction of genetic diversity (He = 0.75), while the group located in the wild registered a higher genetic diversity (He = 0.78) and more private alleles. The genetic differentiation suggested by the Neighbor joining cluster analysis has been strengthened by the two percent (AMOVA) differences between the two groups and highlights the negative impact of brown bear kinship structure, caused by the human expansion on wilderness. The genetic analyses indicated that the two groups share genetic variants due to the dispersal and breeding patterns of male adult bears. The emergence of genetic differences between the two groups can be avoided by preventing bears to become human-food conditioned; over time, kinship structure can pose a threat to genetic diversity.
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