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Povzetek: Genetic markers can assist in the identification of the stock origin in different organisms. Comparative studies of forest tree provenances have demonstrated that forest tree populations differ in performance across environments and at multiple geographic levels: populations nested within regions nested within gene pools. These levels are critical for conservation and sustainable use of genetic resources: regions of provenance are key units for seed marketing, while populations guide reproductive material collection under most seed regulations. Despite their potential, genetic methods have rarely been applied to identify forest tree origins due to methodological (sufficient number of highly discriminatory markers) and practical (construction of a baseline composed of a representative selection of samples) challenges. In our study, we analyzed a genomic dataset comprising 10,185 SNPs from 1579 samples of Pinus pinaster, a species with strong population structure, across 86 populations, 45 regions of provenance, and 10 gene pools, to discriminate among these hierarchical levels and assign individuals to them. We used two software packages to evaluate the reliability of our baseline dataset (i.e., reference data) for genetic discrimination and assignment: RUBIAS, which performs genetic stock identification and associated tasks, and assignPOP, implementing a supervised machine-learning genetic-assignment framework. Using numerical validation analyses, we assessed their suitability and limitations for origin inference at each geographical level. Our results indicate that origin assignment is reliable in P. pinaster at the gene pool and region of provenance levels, but less so at the population level, provided that the 10 K SNP markers and a comprehensive genetic baseline are used. Incomplete baselines may result in wrong assignments at any hierarchical level, irrespective of sampling intensity for sampled candidate origins. We provide an extensive and publicly available baseline for P. pinaster, offering a useful tool for the management of forest genetic resources of this economically and ecologically important tree species.
Ključne besede: gene pool, genetic assignment, maritime pine, origin identification, region of provenance, SNP marker
Objavljeno v DiRROS: 03.12.2025; Ogledov: 346; Prenosov: 154
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Povzetek: Local survival of forest tree populations under climate change depends on existing genetic variation and their adaptability to changing environments. Responses to selection were studied in European beech (Fagus sylvatica) under field conditions. A total of 1,087 adult trees, seeds, one-year-old seedlings, and established multiyear saplings were genotyped with 16 nuSSRs. Adult trees were assessed for phenotypic traits related to growth, phenology and reproduction. Parentage and paternity analyses were used to estimate effective female and male fecundity as a proxy of fitness and showed that few parents contributed to successful regeneration. Selection gradients were estimated from the relationship between traits and fecundity, while heritability and evolvability were estimated using mixed models and the breeder’s equation. Larger trees bearing more fruit and early male flowering had higher total fecundity, while trees with longer growth season had lower total fecundity (directional selection). Stabilising selection on spring phenology was found for female fecundity, highlighting the role of late frosts as a selection driver. Selection gradients for other traits varied between measurement years and the offspring cohort used to estimate parental fecundity. Compared to other studies in natural populations, we found low to moderate heritability and evolvability for most traits. Response to selection was higher for growth than for budburst, leaf senescence or reproduction traits, reflecting more consistent selection gradients across years and sex functions, and higher phenotypic variability in the population. Our study provides empirical evidence suggesting that populations of long-lived organisms such as forest trees can adapt locally, even at short-time scales.
Ključne besede: climate change, Fagus sylvatica, heritability, in situ adaptation, response to selection, selection gradients
Objavljeno v DiRROS: 10.09.2025; Ogledov: 408; Prenosov: 235
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Povzetek: The genetic diversity of forest trees, as provided by Forest Genetic Resources (FGR) and being the basis for the production of Forest Reproductive Material (FRM), is fundamental for maintaining forest resilience, adaptability, health, productivity, and biological diversity. Despite their importance, stakeholder governance of genetic diversity remains under-studied. This study aims to address this gap by mapping the forest stakeholder landscape FGR governance. Using the Quadruple Helix Approach, we categorised stakeholders into academia, industry, government, and civil society identifying relevant sub-communities. The mapping process involved iterative revisions through expert consultations, workshops, and literature scoping. Results show that the FGR sub-community is situated between strict conservation efforts and applied forestry, supporting both genetic conservation and productive forest management. The FRM sub-community, dealing specifically with the production and deployment of FRM, prioritises tree breeding, seed production, and afforestation/reforestation programmes. Meanwhile, the Protected Forests (PF) sub-community focuses on strict nature conservation, advocating minimal human intervention while facing pressures from resource extraction, tourism, and land-use conflicts. The diverging attitudes and values of close-to-nature forest management, intensive forestry, and strict protections, respectively, exist within same stakeholder groups, as well as among different ones, and are spanning all sub-communities. The study uncovers key tensions such as competing land-use priorities between forestry, agriculture, infrastructure and energy sectors, limited flow of knowledge between stakeholder categories and governance misalignments between local, national, and international regulations. The findings are particularly relevant for policymakers, forest managers, forest nurseries, conservation organisations, and industry stakeholders to balance conservation with sustainable forest utilisation. By integrating stakeholder perspectives and highlighting key governance challenges, this study shows where a common ground can be found and where divergent opinions are strong, opening the way for more integrated strategies and policies
Ključne besede: natural resource governance, actors' identification, social-ecological systems, quadruple helix approach, forestry, forest management, biodiversity conservation
Objavljeno v DiRROS: 24.06.2025; Ogledov: 615; Prenosov: 510
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Povzetek: The effect of past environmental changes on the demography and genetic diversity of natural populations remains a contentious issue and has rarely been investigated across multiple, phylogenetically distant species. Here, we perform comparative population genomic analyses and demographic inferences for seven widely distributed and ecologically contrasting European forest tree species based on concerted sampling of 164 populations across their natural ranges. For all seven species, the effective population size, Ne, increased or remained stable over many glacial cycles and up to 15 million years in the most extreme cases. Surprisingly, the drastic environmental changes associated with the Pleistocene glacial cycles have had little impact on the level of genetic diversity of dominant forest tree species, despite major shifts in their geographic ranges. Based on their trajectories of Ne over time, the seven tree species can be divided into three major groups, highlighting the importance of life history and range size in determining synchronous variation in genetic diversity over time. Altogether, our results indicate that forest trees have been able to retain their evolutionary potential over very long periods of time despite strong environmental changes.
Ključne besede: genetic diversity, forest trees, environmental changes
Objavljeno v DiRROS: 29.10.2024; Ogledov: 887; Prenosov: 867
Celotno besedilo (2,69 MB)
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Povzetek: Local survival of forest tree populations under climate change depends on existing genetic variation and their adaptability to changing environments. Responses to selection were studied in European beech (Fagus sylvatica) under field conditions. A total of 1087 adult trees, seeds, 1-year-old seedlings and established multiyear saplings were genotyped with 16 nuSSRs. Adult trees were assessed for phenotypic traits related to growth, phenology and reproduction. Parentage and paternity analyses were used to estimate effective female and male fecundity as a proxy of fitness and showed that few parents contributed to successful regeneration. Selection gradients were estimated from the relationship between traits and fecundity, while heritability and evolvability were estimated using mixed models and the breeder's equation. Larger trees bearing more fruit and early male flowering had higher total fecundity, while trees with longer growth season had lower total fecundity (directional selection). Stabilizing selection on spring phenology was found for female fecundity, highlighting the role of late frosts as a selection driver. Selection gradients for other traits varied between measurement years and the offspring cohort used to estimate parental fecundity. Compared to other studies in natural populations, we found low to moderate heritability and evolvability for most traits. Response to selection was higher for growth than for budburst, leaf senescence or reproduction traits, reflecting more consistent selection gradients across years and sex functions, and higher phenotypic variability in the population. Our study provides empirical evidence suggesting that populations of long-lived organisms such as forest trees can adapt locally, even at short-time scales.
Ključne besede: climate change, Fagus sylvatica, heritability, in situ adaptation, response to selection, selection gradients
Objavljeno v DiRROS: 12.12.2023; Ogledov: 1441; Prenosov: 832
Celotno besedilo (3,53 MB)
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