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Knowledge about the connectivity among natural populations is essential to identify management units for effective conservation actions. Conservation-minded management has led to the recovery of large carnivore populations in northern Europe, possibly restoring connectivity between the two separated, but expanding brown bear (Ursus arctos) populations on the Scandinavian peninsula to the west and Karelia, a part of the large Eurasian population, to the east. The degree of connectivity between these populations has been poorly understood, therefore we investigated the extent of connectivity between the two populations using autosomal microsatellites and Y chromosome haplotypes in 924 male bears (the dispersing sex), sampled during a period of 12 years (2005–2017) across the transborder area where these two populations meet. Our results showed that the two populations are not genetically isolated as reported in earlier studies. We detected recent asymmetrical gene flow at a rate (individuals per generation) of 4.6–5.5 (1%) from Karelia into Scandinavia, whereas the rate was approximately 27.1–34.5 (8%) in the opposite direction. We estimated historical gene flow of effective number of migrants to be between 1.7 and 2.5 between the populations. Analyses of Y chromosome markers supported these results. Successful recovery and expansion of both populations led to the restoration of connectivity, however, it is asymmetric, possibly due to different recovery histories and population densities. By aligning monitoring between neighboring countries, we were able to better understand the biological processes across the relevant spatial scale.

To investigate the potential of association genetics for willow breeding, Salix viminalis germplasm was assembled from UK and Swedish collections (comprising accessions from several European countries) and new samples collected from nature. A subset of the germplasm was planted at two sites (UK and Sweden), genotyped using 38 SSR markers and assessed for phenological and biomass traits. Population structure, genetic differentiation (F-ST) and quantitative trait differentiation (Q(ST)) were investigated. The extent and patterns of trait adaptation were assessed by comparing F-ST and Q(ST) parameters. Of the 505 genotyped diploid accessions, 27 % were not unique. Genetic diversity was high: 471 alleles was amplified; the mean number of alleles per locus was 13.46, mean observed heterozygosity was 0.55 and mean expected heterozygosity was 0.62. Bayesian clustering identified four subpopulations which generally corresponded to Western Russia, Western Europe, Eastern Europe and Sweden. All pairwise F-ST values were highly significant (p<0.001) with the greatest genetic differentiation detected between the Western Russian and the Western European subpopulations (F-ST = 0.12), and the smallest between the Swedish and Eastern European populations (F-ST = 0.04). The Swedish population also had the highest number of identical accessions, supporting the view that S. viminalis was introduced into this country and has been heavily influenced by humans. Q(ST) values were high for growth cessation and leaf senescence, and to some extent stem diameter, but low for bud burst time and shoot number. Overall negative clines between longitudinal coordinates and leaf senescence, bud burst and stem diameter were also found.

To investigate the potential of association genetics for willow breeding, Salix viminalis germplasm was assembled from UK and Swedish collections (comprising accessions from several European countries) and new samples collected from nature. A subset of the germplasm was planted at two sites (UK and Sweden), genotyped using 38 SSR markers and assessed for phenological and biomass traits. Population structure, genetic differentiation (F-ST) and quantitative trait differentiation (Q(ST)) were investigated. The extent and patterns of trait adaptation were assessed by comparing F-ST and Q(ST) parameters. Of the 505 genotyped diploid accessions, 27 % were not unique. Genetic diversity was high: 471 alleles was amplified; the mean number of alleles per locus was 13.46, mean observed heterozygosity was 0.55 and mean expected heterozygosity was 0.62. Bayesian clustering identified four subpopulations which generally corresponded to Western Russia, Western Europe, Eastern Europe and Sweden. All pairwise F-ST values were highly significant (p<0.001) with the greatest genetic differentiation detected between the Western Russian and the Western European subpopulations (F-ST = 0.12), and the smallest between the Swedish and Eastern European populations (F-ST = 0.04). The Swedish population also had the highest number of identical accessions, supporting the view that S. viminalis was introduced into this country and has been heavily influenced by humans. Q(ST) values were high for growth cessation and leaf senescence, and to some extent stem diameter, but low for bud burst time and shoot number. Overall negative clines between longitudinal coordinates and leaf senescence, bud burst and stem diameter were also found.

To investigate the potential of association genetics for willow breeding, Salix viminalis germplasm was assembled from UK and Swedish collections (comprising accessions from several European countries) and new samples collected from nature. A subset of the germplasm was planted at two sites (UK and Sweden), genotyped using 38 SSR markers and assessed for phenological and biomass traits. Population structure, genetic differentiation (F-ST) and quantitative trait differentiation (Q(ST)) were investigated. The extent and patterns of trait adaptation were assessed by comparing F-ST and Q(ST) parameters. Of the 505 genotyped diploid accessions, 27 % were not unique. Genetic diversity was high: 471 alleles was amplified; the mean number of alleles per locus was 13.46, mean observed heterozygosity was 0.55 and mean expected heterozygosity was 0.62. Bayesian clustering identified four subpopulations which generally corresponded to Western Russia, Western Europe, Eastern Europe and Sweden. All pairwise F-ST values were highly significant (p<0.001) with the greatest genetic differentiation detected between the Western Russian and the Western European subpopulations (F-ST = 0.12), and the smallest between the Swedish and Eastern European populations (F-ST = 0.04). The Swedish population also had the highest number of identical accessions, supporting the view that S. viminalis was introduced into this country and has been heavily influenced by humans. Q(ST) values were high for growth cessation and leaf senescence, and to some extent stem diameter, but low for bud burst time and shoot number. Overall negative clines between longitudinal coordinates and leaf senescence, bud burst and stem diameter were also found.

To investigate the potential of association genetics for willow breeding, Salix viminalis germplasm was assembled from UK and Swedish collections (comprising accessions from several European countries) and new samples collected from nature. A subset of the germplasm was planted at two sites (UK and Sweden), genotyped using 38 SSR markers and assessed for phenological and biomass traits. Population structure, genetic differentiation (F-ST) and quantitative trait differentiation (Q(ST)) were investigated. The extent and patterns of trait adaptation were assessed by comparing F-ST and Q(ST) parameters. Of the 505 genotyped diploid accessions, 27 % were not unique. Genetic diversity was high: 471 alleles was amplified; the mean number of alleles per locus was 13.46, mean observed heterozygosity was 0.55 and mean expected heterozygosity was 0.62. Bayesian clustering identified four subpopulations which generally corresponded to Western Russia, Western Europe, Eastern Europe and Sweden. All pairwise F-ST values were highly significant (p<0.001) with the greatest genetic differentiation detected between the Western Russian and the Western European subpopulations (F-ST = 0.12), and the smallest between the Swedish and Eastern European populations (F-ST = 0.04). The Swedish population also had the highest number of identical accessions, supporting the view that S. viminalis was introduced into this country and has been heavily influenced by humans. Q(ST) values were high for growth cessation and leaf senescence, and to some extent stem diameter, but low for bud burst time and shoot number. Overall negative clines between longitudinal coordinates and leaf senescence, bud burst and stem diameter were also found.

The ability of plants to track seasonal changes is largely dependent on genes assigned to the photoperiod pathway, and variation in those genes is thereby important for adaptation to local day length conditions. Extensive physiological data in several temperate conifer species suggest that populations are adapted to local light conditions, but data on the genes underlying this adaptation are more limited. Here we present nucleotide diversity data from 19 genes putatively involved in photoperiodic response in Norway spruce (Picea abies). Based on similarity to model plants the genes were grouped into three categories according to their presumed position in the photoperiod pathway photoreceptors, circadian clock genes, and downstream targets. An HKA (Hudson, Kreitman and Aquade) test showed a significant excess of diversity at photoreceptor genes, but no departure from neutrality at circadian genes and downstream targets. Departures from neutrality were also tested with Tajima's D and Fay and Wu's H statistics under three demographic scenarios the standard neutral model, a population expansion model, and a more complex population split model. Only one gene, the circadian clock gene PaPRR3 with a highly positive Tajima's D value, deviates significantly from all tested demographic scenarios. As the PaPRR3 gene harbours multiple non-synonymous variants it appears as an excellent candidate gene for control of photoperiod response in Norway spruce. © 2014 Källman et al.

To investigate the potential of association genetics for willow breeding, Salix viminalis germplasm was assembled from UK and Swedish collections (comprising accessions from several European countries) and new samples collected from nature. A subset of the germplasm was planted at two sites (UK and Sweden), genotyped using 38 SSR markers and assessed for phenological and biomass traits. Population structure, genetic differentiation (F-ST) and quantitative trait differentiation (Q(ST)) were investigated. The extent and patterns of trait adaptation were assessed by comparing F-ST and Q(ST) parameters. Of the 505 genotyped diploid accessions, 27 % were not unique. Genetic diversity was high: 471 alleles was amplified; the mean number of alleles per locus was 13.46, mean observed heterozygosity was 0.55 and mean expected heterozygosity was 0.62. Bayesian clustering identified four subpopulations which generally corresponded to Western Russia, Western Europe, Eastern Europe and Sweden. All pairwise F-ST values were highly significant (p<0.001) with the greatest genetic differentiation detected between the Western Russian and the Western European subpopulations (F-ST = 0.12), and the smallest between the Swedish and Eastern European populations (F-ST = 0.04). The Swedish population also had the highest number of identical accessions, supporting the view that S. viminalis was introduced into this country and has been heavily influenced by humans. Q(ST) values were high for growth cessation and leaf senescence, and to some extent stem diameter, but low for bud burst time and shoot number. Overall negative clines between longitudinal coordinates and leaf senescence, bud burst and stem diameter were also found.

According to the inclusive fitness theory, some degree of positive relatedness is required for the evolution and maintenance of altruism. However, ant colonies are sometimes large interconnected networks of nests, which are genetically homogenous entities, causing a putative problem for the theory. We studied spatial structure and genetic relatedness in two supercolonies of the ant Formica exsecta, using nuclear and mitochondrial markers. We show that there may be multiple pathways to supercolonial social organization leading to different spatial genetic structures. One supercolony formed a genetically homogenous population dominated by a single mtDNA haplotype, as expected if founded by a small number of colonizers, followed by nest propagation by budding and domination of the habitat patch. The other supercolony had several haplotypes, and the spatial genetic structure was a mosaic of nuclear and mitochondrial clusters. Genetic diversity probably originated from long-range dispersal, and the mosaic population structure is likely a result of stochastic short-range dispersal of individuals. Such a mosaic spatial structure is apparently discordant with the current knowledge about the integrity of ant colonies. Relatedness was low in both populations when estimated among nestmates, but increased significantly when estimated among individuals sharing the same genetic cluster or haplogroup. The latter association indicates the important historical role of queen dispersal in the determination of the spatial genetic structure.

Genomic resources have recently been developed for a number of species of Fagaceae, with the purpose of identifying the genetic factors underlying the adaptation of these long-lived, biologically predominant, commercially and ecologically important species to their environment. The sequencing of genomes of the size of the oak genome (740 Mb/C) is now becoming both possible and affordable due to breakthroughs in sequencing technology. However, an understanding of the composition and structure of the oak genome is required before launching a sequencing initiative. We constructed random (Rd) and hypomethylated (Hp) genomic libraries for pedunculate oak (Quercus robur) and carried out a sample sequencing of 2.33 and 2.36 Mb of shotgun DNA from the Rd and Hp libraries, respectively, to provide a first insight into the repetitive element and gene content of the oak genome. We found striking similarities between Rd sequences and previously analyzed BAC end sequences of pedunculate oak, with a similar percentage of known repeat elements (5.56%), an almost identical simple sequence repeat density (i.e., 29 SSRs per 100 kb), an identical profile of SSR motifs (in descending order of frequency—dinucleotide, pentanucleotide, trinucleotide, tetranucleotide, and hexanucleotide motifs). Conversely, the Hp fraction was, as expected, enriched in nuclear genes (2.44-fold enrichment). This enrichment was associated with a lower frequency of retrotransposons than for Rd sequences. We also identified twice as many SSR motifs in the Rd library as in the Hp library. This work provides useful information before opening a new chapter in oak genome sequencing.

In all, 10 nuclear loci were re-sequenced in four spruce species. Three of the species are boreal species with very large natural ranges: Picea mariana and P. glauca are North American, and P. abies, is Eurasian. The fourth species, P. breweriana, is a Tertiary relict from Northern California, with a very small natural range. Although the boreal species population sizes have fluctuated through the Ice Ages, P. breweriana is believed to have had a rather stable population size through the Quaternary. Indeed, the average Tajima’s D was close to zero in this species and negative in the three boreal ones. Reflecting differences in current population sizes, nucleotide diversity was an order of magnitude lower in P. breweriana than in the boreal species. This is in contrast to the similar and high levels of heterozygosity observed in previous studies at allozyme loci across species. As the species have very different histories and effective population sizes, selection at allozyme loci rather than demography appears to be a better explanation for this discrepancy. Parameters of Isolation-with-Migration (IM) models were also estimated for pairs of species. Shared polymorphisms were extensive and fixed polymorphisms few. Divergence times were much shorter than those previously reported. There was also evidence of historical gene flow between P. abies and P. glauca. The latter was more closely related to P. abies than to its sympatric relative P. mariana. This last result suggests that North American and Eurasian species might have been geographically much closer in the recent past than they are today.

In annual hymenopteran societies headed by a single outbred queen, paternity (determined by queen mating frequency and sperm use) is the sole variable affecting colony kin structure and is therefore a key predictor of colony reproductive characteristics., Addresses: Foster KR, Rice Univ, Anderson Biol Lab 135, MS 170, 6100 Main st, Houston, TX 77005 USA. Univ Sheffield, Dept Anim & Plant Sci, Sheffield S10 2TN, S Yorkshire, England. Uppsala Univ, Dept Conservat Biol & Genet, Evolutionary Biol Ctr, SE-75236