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Scots pine is a crucial component of ecosystems in Europe and Asia and a major utility species that comprises more than 60% of total forest production in Poland. Despite its importance, the genetic relationships between key conservation and the commercial value of Scots pine ecotypes in Poland remain unclear. To address this problem, we analyzed 27 populations (841 trees) of the most valuable Polish Scots pine ecotypes, including the oldest natural stands in all 24 regions of provenance established for the species in the country. By examining maternally inherited mitochondrial markers, nuclear microsatellite loci, and thousands of SNP markers from a genotyping array, we evaluated the genetic structure between and within them. These multilevel genomic data revealed high genetic similarity and a homogeneous structure in most populations, suggesting a common historical origin and admixture of populations after the postglacial recolonization of Central Europe. This research presents novel data on existing genomic resources among local ecotypes defined within strictly managed Polish regions of provenance, challenging their validity. Formal tests of the progeny of seed stands are needed to check whether the diversity in adaptation and quantitative traits still supports the delineation of provenance regions. In parallel, the health status of selected populations and the viability of seeds from these regions should be monitored to detect early‐stage symptoms of their environmental stress. It seems reasonable that periodic shortages of forest reproductive material (FRM) in a given region of provenance could be supplemented with the one from other regions that match their climatic envelope. Together, our results have important implications for the management of native Scots pine stands, particularly elite breeding populations, as they contribute to the discussion of the boundaries of provenance regions and the transfers of FRM that face increasing climate change. [ABSTRACT FROM AUTHOR]

The environment is a powerful selective pressure for sessile organisms, such as plants, and adaptation to the environment is particularly important for long‐lived species, like trees. Despite the importance of adaptive trait variation to the survival and success of trees, the molecular basis of adaptation is still poorly understood. Gene expression patterns in three closely related, but phenotypically and ecologically divergent, pine species were analyzed to detect differentiation that may be associated with their adaptation to distinct environments. Total RNA of Pinus mugo, Pinus uncinata, and Pinus sylvestris samples grown under common garden conditions was used for de novo transcriptome assembly, providing a new reference dataset that includes species from the taxonomically challenging P. mugo complex. Gene expression profiles were found to be very similar with only 121 genes significantly diverged in any of the pairwise species comparisons. Functional annotation of these genes revealed major categories of distinctly expressed transcripts, including wood trait properties, oxidative stress response, and response to abiotic factors such as salinity, drought, and temperature. We discuss putative associations between gene expression profiles and adaptation to different environments, for example, the upregulation of genes involved in lignin biosynthesis in the species, which have adapted to mountainous regions characterized by strong winds and thick snow cover. Our study provides valid candidates for verification of the importance of the gene expression role, in addition to evidence for selection within genomic regions, in the process of ecological divergence and adaptation to higher altitudes in pine taxa. [ABSTRACT FROM AUTHOR]

With the current rate of biodiversity loss, conservation management practices require a comprehensive understanding of eco‐evolutionary relationships, history, and genetic structure of species. Assessments of genetic diversity are crucial, especially in rare, endemic, or threatened forest tree species with small and isolated populations, such as peat bog pine (Pinus uliginosa N.). Here, we used a novel approach, combining genetic diversity assessment, ecological niche modeling, and population demography inference to explore the complex history of a few remnant populations of this endangered pine. To asses the relative influence of isolation and fragmentation on genetic diversity in the taxonomic context, the patterns of genetic variation found in P. uliginosa were contrasted with those observed in its close relatives with much bigger distribution ranges and larger populations (Pinus sylvestris, Pinus mugo, and Pinus uncinata). We found a similar level of genetic diversity across the species at nuclear loci but contrasting patterns of variability distribution at chloroplast markers. We detected the signatures of an ancient genetic bottleneck dated at around 26 400 years ago, indicating a drastic reduction in the population size of P. uligionosa during the Last Glacial Maximum. In addition, we found substantial differentiation between current populations as a result of enhanced genetic drift during long‐lasting isolation. The research suggests potential conservation management strategies for peat bog pine and emphasizes the importance of using complementary approaches for their successful development. [ABSTRACT FROM AUTHOR]

The dwarf mountain pine (Pinus mugo) and the Pyrenean pine (P. uncinata) constitute a pair of closely related coniferous taxa of poorly resolved evolutionary history and affinity, which inhabit numerous stands scattered over subalpine environments of European mountain ranges. The aim of the study was to investigate their phylogeography and mutual relationships, shedding new light on their taxonomy and the past of the alpine flora. Previous evolutionary reconstructions of the mountain pines relied mainly on bi‐parentally or paternally inherited markers that quickly homogenize between populations, showing rather shallow and recent differentiation of gene pools. Therefore, to contrast these pictures, we analyzed diversity and differentiation within a large set of new mitochondrial loci, inherited in maternal line and distributed by seeds at short geographical distances. Samples of the taxa were taken from 27 natural populations representing their range‐wide distributions—17 populations of P. mugo and 10 of P. uncinata. All markers appeared polymorphic, providing a total of 31 multilocus haplotypes. Two of the loci proved to be species‐diagnostic and nearly fixed between analyzed samples. Distribution of mitotypes indicate that allopatric populations of the taxa constitute separate mitochondrial haplogroups, and the two mountain pines have independent evolutionary history. However, introgression of P. mugo mitotypes by P. uncinata specimens revealed in the species contact zone in Western Alps shows that their speciation is not fully completed. [ABSTRACT FROM AUTHOR]

In species where females store sperm, males may try to influence paternity by the strategic placement of sperm within the female's sperm storage organ. Sperm may be mixed or layered in storage organs, and this can influence sperm use beyond a 'fair raffle'. In some insects, sperm from different matings is packaged into discrete packets (spermatodoses), which retain their integrity in the female's sperm storage organ (spermatheca), but little is known about how these may influence patterns of sperm use under natural mating conditions in wild populations. We examined the effect of the size and position of spermatodoses within the spermatheca and number of competing ejaculates on sperm use in female dark bushcrickets ( Pholidoptera griseoaptera) that had mated under unmanipulated field conditions. Females were collected near the end of the mating season, and seven hypervariable microsatellite loci were used to assign paternity of eggs laid in the laboratory. Females contained a median of three spermatodoses (range 1-6), and only six of the 36 females contained more than one spermatodose of the same genotype. Both the size and relative placement of the spermatodoses within the spermatheca had a significant effect on paternity, with a bias against smaller spermatodoses and those further from the single entrance/exit of the spermatheca. A higher number of competing males reduced the chances of siring offspring for each male. Hence, both spermatodose size and relative placement in the spermatheca influence paternity success. [ABSTRACT FROM AUTHOR]