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Pedunculate oak is an economically and ecologically very valuable species at the European level and for Bosnia and Hercegovina, and research into variation of this species is very important. In 2007, pedunculate oak leaf material was collected in 27 populations in Bosnia and Herzegovina along with seeds, which were used to establish a provenance trial. In the trial, leaves were collected in 2021, and 14 morphological traits were measured in both types of material. Analysis of variance showed generally non-significant differences between generations, but significant variation among populations and population-by-generation interactions. However, the correlations between generations were non-significant for most traits, and neither were the correlations with climatic parameters. The results indicate both genetic and environmental effects on leaf morphology. The utility of leaf morphology for gene conservation is shortly discussed.

Norway spruce is expected to suffer from drought stress and other manifestations of climate change. This study relies on a manipulative experiment with drought-stressed and well-watered (control) seedlings, comprising five provenances of Norway spruce distributed along a steep elevational transect from 550 to 1,280 m a.s.l. within the natural range. Seedlings were subjected to measurement of physiological traits (content of phytohormones and monoterpenes, slow and fast chlorophyll a fluorescence kinetics, gas exchange, hyperspectral indices), and genotyping at 8 nuclear microsatellite loci. Comparison of the coefficient of differentiation at neutral loci (FST) vs. differentiation at phenotypic traits (PST) was used to identify traits underlying divergent selection. In total, 18 traits exhibited a significant PST – FST difference. However, the consistency in differentiation patterns between drought-stressed and control plants was limited, only three traits exhibited signals of selection under both treatments. This outcome indicates that the identified differentiation patterns can only be interpreted in the context of environmental setup of the experiment, and highlights the importance of common gardens in adaptation research, as they allow both elimination of environment-induced phenotypic variation and studying genotype-by-environment interaction in physiological responses to environmental stresses.

Silver fir (Abies alba Mill.) is a keystone conifer of European montane forest ecosystems that has experienced large fluctuations in population size during during the Quaternary and, more recently, due to land-use change. To forecast the species' future distribution and survival, it is important to investigate the genetic basis of adaptation to environmental change, notably to extreme events. For this purpose, we here provide a first draft genome assembly and annotation of the silver fir genome, established through a community-based initiative. DNA obtained from haploid megagametophyte and diploid needle tissue was used to construct and sequence Illumina paired-end and mate-pair libraries, respectively, to high depth. The assembled A. alba genome sequence accounted for over 37 million scaffolds corresponding to 18.16 Gb, with a scaffold N50 of 14,051 bp. Despite the fragmented nature of the assembly, a total of 50,757 full-length genes were functionally annotated in the nuclear genome. The chloroplast genome was also assembled into a single scaffold (120,908 bp) that shows a high collinearity with both the A. koreana and A. sibirica complete chloroplast genomes. This first genome assembly of silver fir is an important genomic resource that is now publicly available in support of a new generation of research. By genome-enabling this important conifer, this resource will open the gate for new research and more precise genetic monitoring of European silver fir forests.

European beech is an ecologically and commercially important species, which is expected to decline in several regions because of heat and drought stress associated with climate change. Knowledge of the genetic basis of the adaptation to climate is needed to guide assisted migration. Genetic variation at 1704 single-nucleotide polymorphisms (SNPs) resulting from ddRAD sequencing, primarily located in gene exons, was studied in 181 specimens representing 123 populations distributed over most of the whole range. Bayesian analysis of population structure yielded two clusters exhibiting a clear longitudinal cline and correlated with indicators of low temperatures and temperature fluctuation. Five SNPs were significantly associated with climatic variables related primarily to heat and temperature ranges. Two alternative explanations are offered for the observed response patterns: (i) differential sensitivity to heat and (ii) response mediated by vegetative phenology. [ABSTRACT FROM AUTHOR]

European beech is one of the most common tree species in Europe and is generally suggested to play even more of a prominent role in forestry in the future. It seems to have the potential to partially replace Norway spruce, as it is less sensitive to expected warmer and drier conditions. It is, however, not well known in which regions these new plantings would be particularly favourable and if specific provenances may be better adapted to the new conditions than others. Therefore, we estimated the potential early height growth under climate conditions in 2040–2060 for 20 beech provenances across a region covering the Czech Republic and Slovakia. This Central European region is expected to experience considerably drier and warmer conditions in the future. For this exercise, we implemented a new neural network model developed from height growth information obtained from the open-access BeechCOSTe52 database. The simulations are driven by past and future climate data obtained from the WorldClim database of historical climate data and future climate projections. Simulations revealed that provenances originating from drier regions performed on average significantly better than those from regions with good water supply. Moreover, provenances originating from drier regions had a particularly large advantage in the relatively arid regions of Central Czechia and Southern Slovakia. We can also confirm that all provenances showed a high phenotypic plasticity of height growth across the whole investigated region. [ABSTRACT FROM AUTHOR]