Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2026
Authors
Tor MykingAbstract
No abstract has been registered
Authors
Jan-Peter George Colin Kelleher Aurore Desgroux Eléonore Scholzen Luis Muheim Irena Fundova Gregor Božič Michele Bozzano Anna-Maria FarsakoglouAbstract
This report on dynamic and static ex situ conservation of forest genetic resources is a product of the EUFORGEN Programme. The report serves as a reference document that provides the framework for implementing and monitoring ex situ conservation approaches across Europe, complementing existing in situ conservation efforts. It has been developed through the collective expertise of the EUFORGEN network, establishing minimum requirements and data standards for ex situ conservation, proposing indicators for monitoring, and introducing terminology for genetic conservation units at risk. The actions and strategies addressed in this report are dependent on the commitment of all involved actors, including policymakers, forest managers, researchers, and technical staff responsible for gene banks and genetic conservation units, who will guide the application of dynamic and static ex situ conservation, whenever needed, and provide the financial, human and institutional resources required to effectively conserve forest genetic resources across Europe.
Authors
Katrin Zimmer Ulf Lemke Irena Fundova Henrik Heräjärvi Mateusz Liziniewicz Marlene Cramer Stefanie Wieland Lukas Emmerich Thomas Uibel Anti Rohumaa Heikki Korpunen Grace Jones Ekaterina Nikolskaya Tom Jansen Anneli Adler Tom Mortelmans Ian Short Vincent Defays Karol TomczakAbstract
Birch is the third most abundant tree species in northern Europe and the Baltic region, but remains underutilized in several countries despite wood properties that support a broad range of applications, including pulp, veneer, plywood, furniture, flooring, joinery, and potentially structural products. Constraints on higher-value utilization include insufficient logistics for sorting and transport, the lack of standardized grading methods, and limited data infrastructure for systematic quality assessment across supply chains. The Nordic Forest Research (SNS) network VALUE:BIRCH was established to examine these constraints through transnational collaboration among researchers, industry actors, and students across northern Europe. In 2025 and 2026, the network held workshops in Borås, Sweden, and North Rhine-Westphalia, Germany, with emphasis on strength properties, grading, and quality assessment of birch wood. The activities integrated technical presentations, laboratory and field visits, and student contributions, enabling comparison of birch value chains across countries with differing levels of industrial development. The network identified shared technical and organizational bottlenecks related to birch silviculture and management, grading, mobilization, and market formation, while also strengthening inter-institutional co-creation and collaboration. The results indicate that coordinated work on grading systems, quality data, logistics, and market development is essential to support more efficient and value-adapted utilization of birch.
Abstract
Birch has regained interest in Norwegian forestry within the last few years, partly to increase the share of broadleaves and tree-species diversity under climate change. However, timber yield and quality assortments from Norwegian birch stands remain largely unknown. We established temporary sample plots in planted and naturally regenerated birch stands on high-quality sites in Eastern Norway and carried out tree measurements to quantify stand-level production. In addition, the first 6 m of each standing tree were subjected to a detailed timber‑quality assessment and subsequently graded accordingly. Volume production in the investigated stands was frequently higher than values reported in birch yield tables from the 1970s and did not differ between planted and naturally regenerated stands. Volume production in the studied birch stands was similar to or higher than for Norway spruce on comparable high-quality sites up to a stand age of about 40 years. Despite the lack of quality-oriented management in most stands, nearly all produced sawlogs and many contained higher-quality assortments. Stand-level sawlog proportion increased with mean tree diameter. While planting and thinning showed no clear relationship with stand-level sawlog proportion, artificial pruning increased the share of higher-quality sawlogs. Overall, productive birch stands in Norway can deliver high yields and meaningful volumes of quality sawlogs.
Authors
Dalphy Ondine Camira Harteveld Abdelhameed Elameen Simo Maduna Adam Vivian-Smith Andrea Podavkova Sabine Oettl Stefanie Maria Primisser Jorunn BørveAbstract
Small, superficial rot spots occurring around lenticels postharvest on apple in Norway have not been identified but were assumed to be underdeveloped Neofabraea lesions. Fungal isolation from such spots on fruit from the 2022 season revealed both Neofabraea perennans and Ramularia spp., identified by B-tubulin and ITS sequencing, respectively. In the 2023 season, isolations were made from fruit with spots resembling dry lenticel spot caused by Ramularia mali. The aim of this study was to identify the Ramularia species associated with the postharvest fruit spots in Norway. Multiple gene regions of five Norwegian isolates (E20, E21 from 2022; 13,15 and 18 from 2023) and three reference isolates, R. mali, R. eucalypti, and R. collo-cygni, were sequenced and used for phylogenetic analysis. The Norwegian isolates were distinct from the included reference isolates, but clustered with other Ramularia species. Isolates 13, 18 and E21 clustered with Ramularia vizellae, while isolates 15 and E20 were most closely related to Ramularia phacae-frigidae. Isolate E20 was sequenced using the Oxford Nanopore Technologies MinION platform. Pathogenicity was assessed in a field inoculation study using isolate E21, resulting in typical spot development on inoculated fruit. Ramularia vizellae has previously been reported from dead apple leaf litter and other woody hosts in the Netherlands and Iran, while R. phacae-frigidae was originally described from Phaca frigida in Switzerland. Neither species has previously been reported in association with apple fruit spotting. While Ramularia mali has caused outbreaks on apple in several European countries, recent studies hypothesize that the symptoms may be caused by a species complex with regional variation. The present results identify candidate species contributing to this complex in Norway and highlight the need for further studies to improve species delimitation and pathogenicity.
Abstract
Maximizing genetic response to selection while constraining inbreeding is a central challenge in breeding and conservation. Classic optimal contribution selection methods address this by managing average population coancestry. However, this often results in complex, nonlinear optimization problems that cannot be guaranteed to reach a global optimum. Furthermore, many applications require a stricter pairwise constraint to avoid immediate inbreeding in offspring. Here, we present a binary integer linear programming formulation to select an optimal subset of individuals under a strict maximum tolerable pairwise genomic relationship threshold. We construct a binary matrix indicating whether each pair exceeds this threshold. This reformulation transforms the problem from a complex nonlinear program into a binary integer linear program. While this formulation remains NP-hard, the linearity allows modern solvers to efficiently navigate the solution space and, when convergence is achieved within the imposed runtime and tolerance settings, certify global optimality, a key advantage over heuristic approaches. We demonstrate the method using two distinct datasets: a large Norway spruce breeding population and a conservation population of German Black Pied cattle. We explore the trade-offs between the selection response, the relationship threshold, and the maximum number of individuals that can be selected under the threshold. Although large, dense problem instances remain computationally demanding, our results show that typical applications can often be solved to proven global optimality in seconds, whereas denser instances may terminate with a remaining optimality gap. This method is a practical solution for breeders and conservation geneticists to select optimal subsets under a strict relationship threshold, enabling applications from maximizing gain in breeding populations to establishing genetic reserves for endangered species.
Authors
Rajiv Chaudhary Maximiliano Estravis Barcala Irena Fundova Tomáš Funda Zhi-qiang Chen Harry X. WuAbstract
Background Drought intensity and frequency are increasing under global warming in the boreal forests, and breeding for drought resistance will facilitate adaptation of new planting material to changing climate conditions. We used a tree-ring dataset of 559 individuals to study Scots pine genetic variation and the efficiency of genomic selection of drought-response traits (drought resistance, recovery and resilience), for the first time. From genotyping-by-sequencing (GBS), 31,101 SNPs were generated and used for the study. Results Significant genetic variation was detected for drought-response and other growth, wood-anatomy and wood density traits. Heritability estimates for wood-anatomical traits were higher than those for drought-response and growth traits. Genetic correlations between drought-response and wood-anatomical traits were generally high but mostly nonsignificant. In contrast, drought resistance and recovery showed positive and significant correlations with basal area increment and height. We found that the predictive ability and accuracy for drought-response traits were lower than those for wood-anatomical traits, and were comparable between GBLUP and ABLUP. Greater genetic gain per year can be achieved through genomic selection relative to pedigree-based selection if the generation interval is reduced. Conclusions The positive genetic correlation between drought-response and growth traits will enable simultaneous selection for improved growth and increased drought resistant trees in Scots pine breeding through either pedigreed-based and genomic selection.
Abstract
No abstract has been registered
Abstract
Incidence of the spruce gall adelgid ( Adelges abietis ; “spruce gall aphid” sensu common usage) was assessed as presence/absence in Norway spruce trials in Norway. The trial series comprised a long-term provenance test, a short-term provenance test (36 provenances), three diallel populations (10×10, 10×10, 9×9), a 10×10 factorial cross (100 families), and a clonal test (40 clones). Substantial genetic variation in gall incidence was observed among provenances, among families, and among clones within families. Provenances transferred from low- to mid-elevation Central Europe exhibited higher gall incidence than Nordic and Baltic origins, whereas high-elevation Central European material showed lower incidence. Family-level variation was detected in both natural-population diallels and breeding-population factorial material; a strong agreement was observed between family and derived clone performance (family–clone r ≈ 0.91). Variance-component analyses indicated predominantly additive genetic control, with additional non-additive effects in some crosses. Corresponding narrow-sense heritability estimates were low to moderate (≈ 0.06–0.22). Site effects were evident, with higher expression associated with greater vigor on fertile soils in some trials. Overall, the results indicate that selection for reduced galling is feasible and that provenance choice and site fertility should be considered in deployment and climate-adaptation strategies.
2025
Authors
Alexandro B. Leverkus María Medina Alba Lazaro-Gonzalez Laura Levy Olivia Lorente-Casalini Marino P. Reyes Martín Enrique Andivia Alessandro Bizzarri Henrik Böhlenius Vito E. Cambria Claudia Cocozza Branislav Cvjetkovic Giovanbattista de Dato Lenka Ehrenbergerova Peter Ferus Lorena Gomez-Aparicio Arndt Hampe Kjersti Holt Hanssen Marcin Jakubowski Ivona Kerkez Jankovic Marcin Klisz Wojciech Kowalkowski Klaus Kremer Jelena Lazarevic Dagnija Lazdina Emanuele Lingua Magnus Löf Manuel E. Lucas-Borja Adrian Łukowski Paula Maia Paola Mairota Alberto Maltoni Barbara Mariotti Raffaella Marzano Lucia Mondanelli Antonio Montagnoli Maria Cristina Monteverdi Francisco B. Navarro Reyes Juan A. Oliet Maria S. Patrício Zoran Poduska Vladan Popovic Radosław Puchałka Piotr Robakowski Piotr Sewerniak Carmen Urena-Lara Pedro Villar-Salvador Johanna Witzell Nicolo Anselmetto Inger Sundheim FløistadAbstract
Seedling emergence constitutes a critical recruitment step, and early growth relates to plant competitive ability. Understanding their drivers has implications for forestry and forest ecosystem conservation, restoration, and adaptation to climate change. We seeded 6984 acorns in an experiment with 97 cases at 45 sites in 15 European countries, encompassing 12 oak species. We tested whether the quality of the acorn batch, site-level weather and soil characteristics, year of seeding, and species’ mean specific leaf area (SLA) affected the emergence and early growth of seedlings after the first summer. Germination potential and acorn dry weight, measured under controlled conditions, were positively associated with emergence and early growth. Seedling emergence was negatively associated with the mean monthly temperature and cumulative winter precipitation, and it was higher in the seedling cohort that was spared from the 2021 drought. Additionally, seedling emergence was positively related to soil nutrient concentration and negatively to increasing soil pH, but not to water-holding capacity, and growth was unrelated to soils. Species-level SLA was not related to either response. The four main study species –Quercus cerris, Q. ilex, Q. petraea, and Q. robur– responded similarly to weather but not to soil conditions. We conclude that, at a continental scale, and assuming that species establish within their current distributions, (a) oak seedling emergence and early growth are associated with acorn quality rather than species identity or SLA, (b) they are highest at sites with low winter precipitation and temperature, (c) emergence is reduced in dry years, and d) soil properties play a secondary role at this early recruitment stage.