TY - JOUR A1 - Schleuning, Matthias A1 - Templin, Mathias A1 - Huaman, Vicky A1 - Vadillo, Giovana P. A1 - Becker, Thomas A1 - Durka, Walter A1 - Fischer, Markus A1 - Matthies, Diethart T1 - Effects of inbreeding, outbreeding, and supplemental pollen on the reproduction of a hummingbird-pollinated clonal amazonian herb JF - Biotropica : a publication of the Association for Tropical Biology N2 - Understory herbs are an essential part of tropical rain forests, but little is known about factors limiting their reproduction. Many of these herbs are clonal, patchily distributed, and produce large floral displays of nectar-rich 1-d flowers to attract hummingbird pollinators that may transport pollen over long distances. The aim of this study was to investigate the effects of clonality, cross-proximity, and patchy distribution on the reproduction of the hummingbird-pollinated Amazonian herb Heliconia metallica. We experimentally pollinated flowers within populations with self-pollen and with pollen of different diversity, crossed flowers between populations, and added supplemental pollen to ramets growing solitarily or in conspecific patches. Only flowers pollinated early in the morning produced seeds. Selfed flowers produced seeds, but seed number and mass were strongly reduced, suggesting partial sterility and inbreeding depression after selfing. Because of pollen competition, flowers produced more seeds after crosses with several than with single donor plants. Crosses between populations mostly resulted in lower seed production than those within populations, suggesting outbreeding depression. Ramets in patches produced fewer seeds than solitary ramets and were more pollen-limited, possibly due to geitonogamy and biparental inbreeding in patches. We conclude that high rates of geitonogamy due to clonality and pollen limitation due to the short receptivity of flowers and patchy distribution constrain the reproduction of this clonal herb. Even in unfragmented rain forests with highly mobile pollinators, outbreeding depression may be a widespread phenomenon in plant reproduction. KW - clonality KW - geitonogamy KW - Heliconiaceae KW - hummingbird pollination KW - Peru KW - pollen limitation KW - pollination experiment KW - rain forest understory Y1 - 2011 U6 - https://doi.org/10.1111/j.1744-7429.2010.00663.x SN - 0006-3606 VL - 43 IS - 2 SP - 183 EP - 191 PB - Wiley-Blackwell CY - Malden ER - TY - JOUR A1 - Michalski, S A1 - Gautschi, B A1 - Burkart, Michael A1 - Durka, Walter T1 - Isolation and characterization of microsatellite loci in the rush Juncus atratus (Juncaceae) Y1 - 2006 ER - TY - JOUR A1 - Meyer, Jork A1 - Kohnen, Annette A1 - Durka, Walter A1 - Wöstemeyer, Johannes A1 - Blaum, Niels A1 - Rossmanith, Eva A1 - Brandl, Roland T1 - Genetic structure and dispersal in a small South African Rodent : is dispersal female-biased? N2 - Dispersal greatly determines genetic structure of populations, although it is influenced by landscape heterogeneity, quality of the matrix, resource distribution and local population densities and dynamics. To get insights into some of those processes we analysed the genetic structure of the hairy-footed gerbil Gerbillurus paeba (Rodentia, Murinae, Gerbillinae) in the southern Kalahari (South Africa). Samples were taken from 20 populations covering an area of about 2200 km2. Genetic data were related to landscape characters and population dynamics. We used newly developed microsatellites and found at all loci some indication for the presence of null alleles. However, null alleles seem to have little influence on the general results of our analyses. Altogether we found even nearby populations of G. paeba to be significantly differentiated, although assignment tests revealed 24% of individuals as immigrants. Genetic structure was independent of landscape heterogeneities at all spatial scales. Autocorrelation analyses (range 50-90 km) revealed significant genetic structure within populations on distances <3 km. We found some indication for female-biased dispersal. Our study suggests that dispersing individuals have little influence on the long-term genetic structure and that drift is the major cause of genetic diversity. The observed genetic pattern likely derives from strong population fluctuations of G. paeba. The landscape structure has little influence on the genetic differentiation between populations. Y1 - 2009 UR - http://www.sciencedirect.com/science/journal/16165047 U6 - https://doi.org/10.1016/j.mambio.2008.11.004 SN - 1616-5047 ER - TY - GEN A1 - Marcus, Tamar A1 - Boch, Steffen A1 - Durka, Walter A1 - Gossner, Martin M. A1 - Müller, Jörg A1 - Schöning, Ingo A1 - Weisser, Wolfgang W. A1 - Drees, Claudia A1 - Assmann, Thorsten T1 - Living in heterogeneous woodlands BT - are habitat continuity or quality drivers of genetic variability in a flightless ground beetle? T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Abstract Although genetic diversity is one of the key components of biodiversity, its drivers are still not fully understood. While it is known that genetic diversity is affected both by environmental parameters as well as habitat history, these factors are not often tested together. Therefore, we analyzed 14 microsatellite loci in Abax parallelepipedus, a flightless, forest dwelling ground beetle, from 88 plots in two study regions in Germany. We modeled the effects of historical and environmental variables on allelic richness, and found for one of the regions, the Schorfheide-Chorin, a significant effect of the depth of the litter layer, which is a main component of habitat quality, and of the sampling effort, which serves as an inverse proxy for local population size. For the other region, the Schwabische Alb, none of the potential drivers showed a significant effect on allelic richness. We conclude that the genetic diversity in our study species is being driven by current local population sizes via environmental variables and not by historical processes in the studied regions. This is also supported by lack of genetic differentiation between local populations sampled from ancient and from recent woodlands. We suggest that the potential effects of former fragmentation and recolonization processes have been mitigated by the large and stable local populations of Abax parallelepipedus in combination with the proximity of the ancient and recent woodlands in the studied landscapes. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 508 KW - forest management intensity KW - lichen Lobaria pulmonaria KW - past land-use KW - carabid beetles KW - distribution patterns KW - environmental-factors KW - conifer plantations KW - population-genetics KW - species composition KW - plant diversity Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-408451 SN - 1866-8372 IS - 508 ER - TY - JOUR A1 - Marcus, Tamar A1 - Boch, Steffen A1 - Durka, Walter A1 - Fischer, Markus A1 - Gossner, Martin M. A1 - Müller, Jörg A1 - Schöning, Ingo A1 - Weisser, Wolfgang W. A1 - Drees, Claudia A1 - Assmann, Thorsten T1 - Living in Heterogeneous Woodlands - Are Habitat Continuity or Quality Drivers of Genetic Variability in a Flightless Ground Beetle? JF - PLoS one N2 - Although genetic diversity is one of the key components of biodiversity, its drivers are still not fully understood. While it is known that genetic diversity is affected both by environmental parameters as well as habitat history, these factors are not often tested together. Therefore, we analyzed 14 microsatellite loci in Abax parallelepipedus, a flightless, forest dwelling ground beetle, from 88 plots in two study regions in Germany. We modeled the effects of historical and environmental variables on allelic richness, and found for one of the regions, the Schorfheide-Chorin, a significant effect of the depth of the litter layer, which is a main component of habitat quality, and of the sampling effort, which serves as an inverse proxy for local population size. For the other region, the Schwabische Alb, none of the potential drivers showed a significant effect on allelic richness. We conclude that the genetic diversity in our study species is being driven by current local population sizes via environmental variables and not by historical processes in the studied regions. This is also supported by lack of genetic differentiation between local populations sampled from ancient and from recent woodlands. We suggest that the potential effects of former fragmentation and recolonization processes have been mitigated by the large and stable local populations of Abax parallelepipedus in combination with the proximity of the ancient and recent woodlands in the studied landscapes. Y1 - 2015 U6 - https://doi.org/10.1371/journal.pone.0144217 SN - 1932-6203 VL - 10 IS - 12 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Lachmuth, Susanne A1 - Durka, Walter A1 - Schurr, Frank Martin T1 - Differentiation of reproductive and competitive ability in the invaded range of Senecio inaequidens the role of genetic Allee effects, adaptive and nonadaptive evolution JF - New phytologist : international journal of plant science N2 - Genetic differentiation in the competitive and reproductive ability of invading populations can result from genetic Allee effects or r/K selection at the local or range-wide scale. However, the neutral relatedness of populations may either mask or falsely suggest adaptation and genetic Allee effects. In a common-garden experiment, we investigated the competitive and reproductive ability of invasive Senecio inaequidens populations that vary in neutral genetic diversity, population age and field vegetation cover. To account for population relatedness, we analysed the experimental results with 'animal models' adopted from quantitative genetics. Consistent with adaptive r/K differentiation at local scales, we found that genotypes from low-competition environments invest more in reproduction and are more sensitive to competition. By contrast, apparent effects of large-scale r/K differentiation and apparent genetic Allee effects can largely be explained by neutral population relatedness. Invading populations should not be treated as homogeneous groups, as they may adapt quickly to small-scale environmental variation in the invaded range. Furthermore, neutral population differentiation may strongly influence invasion dynamics and should be accounted for in analyses of common-garden experiments. KW - animal models KW - biological invasions KW - genetic Allee effects KW - interspecific competition KW - life history evolution KW - nonadaptive evolution KW - r and K selection KW - reproduction Y1 - 2011 U6 - https://doi.org/10.1111/j.1469-8137.2011.03808.x SN - 0028-646X VL - 192 IS - 2 SP - 529 EP - 541 PB - Wiley-Blackwell CY - Malden ER - TY - JOUR A1 - Kloss, Lena A1 - Fischer, Markus A1 - Durka, Walter T1 - Land-use effects on genetic structure of a common grassland herb a matter of scale JF - Basic and applied ecology : Journal of the Gesellschaft für Ökologie N2 - The most common management practices in European grasslands are grazing by livestock and mowing for silage and hay. Grazing and mowing differ in their potential effects on plant gene flow and resulting population genetic structure. After assessing its breeding system, we investigated the effect of land use on the population genetic structure in the common grassland plant Veronica chamaedrys using 63 study populations on meadows, mown pastures and pastures in three regions in Germany, the so-called Biodiversity Exploratories. We determined plant density and analysed the genetic diversity, differentiation and small-scale genetic structure using amplified fragment length polymorphism (AFLP) markers. The breeding system of V chamaedrys turned out as self-incompatible and outcrossing. Its genetic diversity did not differ among land-use types. This may be attributed to large population sizes and the strong dispersal ability of the species, which maintains genetically diverse populations not prone to genetic drift. Genetic differentiation among populations was low (overall F(ST) = 0.075) but significant among the three regions. Land use had only weak effects on population differentiation in only one region. However, land use affected small-scale genetic structure suggesting that gene flow within plots was more restricted on meadows than on mown and unmown pastures. Our study shows that land use influences genetic structure mainly at the small scale within populations, despite high gene flow. KW - Biodiversity exploratories KW - Mowing KW - Grazing KW - AFLP KW - Veronica KW - Breeding system KW - Pollination experiment KW - Pollen-ovule ratio KW - Isolation by distance KW - Spatial autocorrelation Y1 - 2011 U6 - https://doi.org/10.1016/j.baae.2011.06.001 SN - 1439-1791 VL - 12 IS - 5 SP - 440 EP - 448 PB - Elsevier CY - Jena ER - TY - JOUR A1 - Eckert, Silvia A1 - Herden, Jasmin A1 - Stift, Marc A1 - Durka, Walter A1 - Kleunen, Mark Van A1 - Joshi, Jasmin Radha T1 - Traces of Genetic but Not Epigenetic Adaptation in the Invasive Goldenrod Solidago canadensis Despite the Absence of Population Structure JF - Frontiers in Ecology and Evolution N2 - Biological invasions may result from multiple introductions, which might compensate for reduced gene pools caused by bottleneck events, but could also dilute adaptive processes. A previous common-garden experiment showed heritable latitudinal clines in fitness-related traits in the invasive goldenrod Solidago canadensis in Central Europe. These latitudinal clines remained stable even in plants chemically treated with zebularine to reduce epigenetic variation. However, despite the heritability of traits investigated, genetic isolation-by-distance was non-significant. Utilizing the same specimens, we applied a molecular analysis of (epi)genetic differentiation with standard and methylation-sensitive (MSAP) AFLPs. We tested whether this variation was spatially structured among populations and whether zebularine had altered epigenetic variation. Additionally, we used genome scans to mine for putative outlier loci susceptible to selection processes in the invaded range. Despite the absence of isolation-by-distance, we found spatial genetic neighborhoods among populations and two AFLP clusters differentiating northern and southern Solidago populations. Genetic and epigenetic diversity were significantly correlated, but not linked to phenotypic variation. Hence, no spatial epigenetic patterns were detected along the latitudinal gradient sampled. Applying genome-scan approaches (BAYESCAN, BAYESCENV, RDA, and LFMM), we found 51 genetic and epigenetic loci putatively responding to selection. One of these genetic loci was significantly more frequent in populations at the northern range. Also, one epigenetic locus was more frequent in populations in the southern range, but this pattern was lost under zebularine treatment. Our results point to some genetic, but not epigenetic adaptation processes along a large-scale latitudinal gradient of S. canadensis in its invasive range. KW - AFLP KW - MSAP KW - cytosine methylation KW - spatial autocorrelation KW - genome scan Y1 - 2022 U6 - https://doi.org/10.3389/fevo.2022.856453 SN - 2296-701X VL - 10 SP - 1 EP - 17 PB - Frontiers CY - Lausanne, Schweiz ER - TY - JOUR A1 - Eckert, Silvia A1 - Herden, Jasmin A1 - Stift, Marc A1 - Durka, Walter A1 - Kleunen, Mark Van A1 - Joshi, Jasmin Radha T1 - Traces of Genetic but Not Epigenetic Adaptation in the Invasive Goldenrod Solidago canadensis Despite the Absence of Population Structure JF - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Biological invasions may result from multiple introductions, which might compensate for reduced gene pools caused by bottleneck events, but could also dilute adaptive processes. A previous common-garden experiment showed heritable latitudinal clines in fitness-related traits in the invasive goldenrod Solidago canadensis in Central Europe. These latitudinal clines remained stable even in plants chemically treated with zebularine to reduce epigenetic variation. However, despite the heritability of traits investigated, genetic isolation-by-distance was non-significant. Utilizing the same specimens, we applied a molecular analysis of (epi)genetic differentiation with standard and methylation-sensitive (MSAP) AFLPs. We tested whether this variation was spatially structured among populations and whether zebularine had altered epigenetic variation. Additionally, we used genome scans to mine for putative outlier loci susceptible to selection processes in the invaded range. Despite the absence of isolation-by-distance, we found spatial genetic neighborhoods among populations and two AFLP clusters differentiating northern and southern Solidago populations. Genetic and epigenetic diversity were significantly correlated, but not linked to phenotypic variation. Hence, no spatial epigenetic patterns were detected along the latitudinal gradient sampled. Applying genome-scan approaches (BAYESCAN, BAYESCENV, RDA, and LFMM), we found 51 genetic and epigenetic loci putatively responding to selection. One of these genetic loci was significantly more frequent in populations at the northern range. Also, one epigenetic locus was more frequent in populations in the southern range, but this pattern was lost under zebularine treatment. Our results point to some genetic, but not epigenetic adaptation processes along a large-scale latitudinal gradient of S. canadensis in its invasive range. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1271 KW - AFLP KW - MSAP KW - cytosine methylation KW - spatial autocorrelation KW - genome scan Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-566758 SN - 1866-8372 SP - 1 EP - 17 PB - Universitätsverlag Potsdam CY - Potsdam ER -