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  • 151.
    Favre, Adrien
    et al.
    Swiss Fed Inst Technol, Plant Ecol Genet, Inst Integrat Biol, Univ Str 16, CH-8092 Zurich, Switzerland.;Univ Leipzig, Inst Biol, Dept Mol Evolut & Plant Systemat & Herbarium LZ, Johannisallee 21-23, D-04103 Leipzig, Germany..
    Widmer, Alex
    Swiss Fed Inst Technol, Plant Ecol Genet, Inst Integrat Biol, Univ Str 16, CH-8092 Zurich, Switzerland..
    Karrenberg, Sophie
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Swiss Fed Inst Technol, Plant Ecol Genet, Inst Integrat Biol, Univ Str 16, CH-8092 Zurich, Switzerland..
    Differential adaptation drives ecological speciation in campions (Silene): evidence from a multi-site transplant experiment2017In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 213, no 3, p. 1487-1499Article in journal (Refereed)
    Abstract [en]

    In order to investigate the role of differential adaptation for the evolution of reproductive barriers, we conducted a multi-site transplant experiment with the dioecious sister species Silenedioica and S.latifolia and their hybrids. Crosses within species as well as reciprocal first-generation (F-1) and second-generation (F-2) interspecific hybrids were transplanted into six sites, three within each species' habitat. Survival and flowering were recorded over 4yr. At all transplant sites, the local species outperformed the foreign species, reciprocal F-1 hybrids performed intermediately and F-2 hybrids underperformed in comparison to F-1 hybrids (hybrid breakdown). Females generally had slightly higher cumulative fitness than males in both within- and between-species crosses and we thus found little evidence for Haldane's rule acting on field performance. The strength of selection against F-1 and F-2 hybrids as well as hybrid breakdown increased with increasing strength of habitat adaptation (i.e. the relative fitness difference between the local and the foreign species) across sites. Our results suggest that differential habitat adaptation led to ecologically dependent post-zygotic reproductive barriers and drives divergence and speciation in this Silene system.

  • 152.
    Feurtey, Alice
    et al.
    Univ Paris Saclay, AgroParisTech, CNRS, Ecol Systemat Evolut,Univ Paris Sud, Orsay, France..
    Cornille, Amandine
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Uppsala University, Science for Life Laboratory, SciLifeLab. Univ Paris Saclay, AgroParisTech, CNRS, Ecol Systemat Evolut,Univ Paris Sud, Orsay, France.;Swiss Fed Inst Technol, Adaptat Changing Environm, Zurich, Switzerland.;Swiss Fed Inst Technol, Inst Integrat Biol, Zurich, Switzerland..
    Shykoff, Jacqui A.
    Univ Paris Saclay, AgroParisTech, CNRS, Ecol Systemat Evolut,Univ Paris Sud, Orsay, France..
    Snirc, Alodie
    Univ Paris Saclay, AgroParisTech, CNRS, Ecol Systemat Evolut,Univ Paris Sud, Orsay, France..
    Giraud, Tatiana
    Univ Paris Saclay, AgroParisTech, CNRS, Ecol Systemat Evolut,Univ Paris Sud, Orsay, France..
    Crop-to-wild gene flow and its fitness consequences for a wild fruit tree: Towards a comprehensive conservation strategy of the wild apple in Europe2017In: Evolutionary Applications, ISSN 1752-4571, E-ISSN 1752-4571, Vol. 10, no 2, p. 180-188Article in journal (Refereed)
    Abstract [en]

    Crop-to-wild gene flow can reduce the fitness and genetic integrity of wild species. Malus sylvestris, the European crab-apple fruit tree in particular, is threatened by the disappearance of its habitat and by gene flow from its domesticated relative, Malus domestica. With the aims of evaluating threats for M.sylvestris and of formulating recommendations for its conservation, we studied here, using microsatellite markers and growth experiments: (i) hybridization rates in seeds and trees from a French forest and in seeds used for replanting crab apples in agrosystems and in forests, (ii) the impact of the level of M.domestica ancestry on individual tree fitness and (iii) pollen dispersal abilities in relation to crop-to-wild gene flow. We found substantial contemporary crop-to-wild gene flow in crab-apple tree populations and superior fitness of hybrids compared to wild seeds and seedlings. Using paternity analyses, we showed that pollen dispersal could occur up to 4km and decreased with tree density. The seed network furnishing the wild apple reintroduction agroforestry programmes was found to suffer from poor genetic diversity, introgressions and species misidentification. Overall, our findings indicate supported threats for the European wild apple steering us to provide precise recommendations for its conservation.

  • 153. Flores-Sandoval, Eduardo
    et al.
    Eklund, D. Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Bowman, John L.
    A simple auxin transcriptional response system regulates multiple morphogenetic processes in the liverwort Marchantia polymorpha2015In: PLOS Genetics, ISSN 1553-7390, E-ISSN 1553-7404, Vol. 11, no 5, article id e1005207Article in journal (Refereed)
    Abstract [en]

    In land plants comparative genomics has revealed that members of basal lineages share a common set of transcription factors with the derived flowering plants, despite sharing few homologous structures. The plant hormone auxin has been implicated in many facets of development in both basal and derived lineages of land plants. We functionally characterized the auxin transcriptional response machinery in the liverwort Marchantia polymorpha, a member of the basal lineage of extant land plants. All components known from flowering plant systems are present in Mpolymorpha, but they exist as single orthologs: a singleMpTOPLESS (TPL) corepressor, a single MpTRANSPORT INHIBITOR RESPONSE 1 auxin receptor, single orthologs of each class of AUXIN RESPONSE FACTOR (ARF; MpARF1,MpARF2MpARF3), and a single negative regulator AUXIN/INDOLE-3-ACETIC ACID (MpIAA). Phylogenetic analyses suggest this simple system is the ancestral condition for land plants. We experimentally demonstrate that these genes act in an auxin response pathway — chimeric fusions of the MpTPL corepressor with heterodimerization domains of MpARF1, MpARF2, or their negative regulator, MpIAA, generate auxin insensitive plants that lack the capacity to pattern and transition into mature stages of development. Our results indicate auxin mediated transcriptional regulation acts as a facilitator of branching, differentiation and growth, rather than acting to determine or specify tissues during the haploid stage of the M.polymorpha life cycle. We hypothesize that the ancestral role of auxin is to modulate a balance of differentiated and pluri- or totipotent cell states, whose fates are determined by interactions with combinations of unrelated transcription factors.

  • 154.
    Fogelqvist, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics.
    Niittyvuopio, Anne
    Ågren, Jon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Savolainen, Outi
    Lascoux, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics.
    Cryptic population genetic structure: the number of inferred clusters depends on sample size2010In: Molecular Ecology Resources, ISSN 1755-098X, Vol. 10, no 2, p. 314-323Article in journal (Refereed)
    Abstract [en]

    Clustering methods have been used extensively to unravel cryptic population genetic structure. We investigated the effect of the number of individuals sampled in each location on the resulting number of clusters. Our study was motivated by recent results in Arabidopsis thaliana: studies in which more than one individual was sampled per location apparently have led to a much higher number of clusters than studies where only one individual was sampled in each location, as is generally done in this species. We show, using computer simulations and microsatellite data in A. thaliana, that the number of sampled individuals indeed has a strong impact on the number of resulting clusters. This effect is smaller if the sampled populations have a hierarchical structure. In most cases, sampling 5-10 individuals per population should be enough. The results argue for abandoning the concept of 'accessions' in partially selfing organisms.

  • 155.
    Fogelqvist, Johan
    et al.
    Swedish Univ Agr Sci, Uppsala BioCtr, Linnean Ctr Plant Biol, Dept Plant Biol, SE-75007 Uppsala, Sweden..
    Verkhozina, Alla V.
    Siberian Inst Plant Physiol & Biochem, Irkutsk 664033, Russia..
    Katyshev, Alexander I.
    Siberian Inst Plant Physiol & Biochem, Irkutsk 664033, Russia..
    Pucholt, Pascal
    Swedish Univ Agr Sci, Uppsala BioCtr, Linnean Ctr Plant Biol, Dept Plant Biol, SE-75007 Uppsala, Sweden..
    Dixelius, Christina
    Swedish Univ Agr Sci, Uppsala BioCtr, Linnean Ctr Plant Biol, Dept Plant Biol, SE-75007 Uppsala, Sweden..
    Ronnberg-Wastljung, Ann Christin
    Swedish Univ Agr Sci, Uppsala BioCtr, Linnean Ctr Plant Biol, Dept Plant Biol, SE-75007 Uppsala, Sweden..
    Lascoux, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Berlin, Sofia
    Swedish Univ Agr Sci, Uppsala BioCtr, Linnean Ctr Plant Biol, Dept Plant Biol, SE-75007 Uppsala, Sweden..
    Genetic and morphological evidence for introgression between three species of willows2015In: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 15, article id 193Article in journal (Refereed)
    Abstract [en]

    Background: Hybridization and introgression are said to occur relatively frequently in plants, and in particular among different species of willows. However, data on the actual frequency of natural hybridization and introgression is rare. Here, we report the first fine-scale genetic analysis of a contact zone shared between the three basket willow species, Salix dasyclados, S. schwerinii and S. viminalis in the vicinity of the Lake Baikal in Southern Siberia. Individuals were sampled in fourteen populations and classified as pure species or hybrids based on a set of morphological characters. They were then genotyped at 384 nuclear SNP and four chloroplast SSR loci. The STRUCTURE and NewHybrids softwares were used to estimate the frequency and direction of hybridization using genotypic data at the nuclear SNP loci. Results: As many as 19 % of the genotyped individuals were classified as introgressed individuals and these were mainly encountered in the centre of the contact zone. All introgressed individuals were backcrosses to S. viminalis or S. schwerinii and no F1 or F2 hybrids were found. The rest of the genotyped individuals were classified as pure species and formed two clusters, one with S. schwerinii individuals and the other with S. viminalis and S. dasyclados individuals. The two clusters were significantly genetically differentiated, with F-ST = 0.333 (0.282-0.382, p < 0.001). In contrast, for the chloroplast haplotypes, no genetic differentiation was observed as they were completely shared between the species. Based on morphological classification only 5 % of the individuals were classified as introgressed individuals, which was much less than what was detected using genotypic data. Conclusions: We have discovered a new willow hybrid zone with relatively high frequency of introgressed individuals. The low frequency of F1 hybrids indicates that ongoing hybridization is limited, which could be because of the presence of reproductive barriers or simply because the conditions are not favorable for hybridization. We further conclude that in order to get a complete picture of the species composition of a hybrid zone it is necessary to use a combination of morphological characters and genetic data from both nuclear and chloroplast markers.

  • 156.
    Fredga, Karl
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Mäler, Karl-Göran
    Life Cycle Analyses and Resource Assessments2010In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 39, no Suppl. 1, p. 36-41Article in journal (Refereed)
    Abstract [en]

    Prof. Ulgiati stresses that we should always use an ecosystem view when transforming energy from one form to another. Sustainable growth and development of both environmental and human-dominated systems require optimum use of available resources for maximum power output. We have to adapt to the laws of nature because nature has to take care of all the waste products we produce. The presentation addresses a much needed shift away from linear production and consumption pattern, toward reorganization of economies and lifestyle that takes complexity—of resources, of the environment and of the economy—into proper account. The best way to reach maximum yield from the different kinds of biomass is to use biorefineries. Biorefinery is defined as the sustainable processing of biomass into a spectrum of marketable products like heat, power, fuels, chemicals, food, feed, and materials. However, biomass from agricultural land must be used for the production of food and not fuel. Prof. Voss focuses on the sustainability of energy supply chains and energy systems. Life cycle analyses (LCA) provides the conceptual framework for a comprehensive comparative evaluation of energy supply options with regard to their resource requirements as well as the health and environmental impact. Full scope LCA considers not only the emissions from plant operation, construction, and decommissioning but also the environmental burdens and resource requirements associated with the entire lifetime of all relevant upstream and downstream processes within the energy chain. This article describes the results of LCA analyses for state-of-the-art heating and electricity systems as well as of advanced future systems. Total costs are used as a measure for the overall resource consumption.

  • 157.
    Fredga, Karl
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Stjernberg, Torsten
    Svanberg, Ingvar
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Uppsala Centre for Russian and Eurasian Studies.
    An early (1834) illustration of the wood lemming, Myopus schisticolor (Lilljeborg, 1844), from Finland2011In: Archives of Natural History, ISSN 0260-9541, E-ISSN 1755-6260, Vol. 38, no 2, p. 214-219Article in journal (Refereed)
    Abstract [en]

    The wood lemming, Myopus schisticolor, was described as a new species by the Swedish zoologist Wilhelm Lilljeborg in 1844 from a specimen captured in Norway the year before. With the original description was a fine hand-coloured lithograph by the artist Magnus Korner. A Latin translation of the description published later that year also used an illustration by Korner, but it was of lesser quality. However, the species had been observed, described and depicted earlier, but these renderings never reached the scientific community. In 2008 and 2009 respectively, one illustration of the wood lemming made by the Finnish-born artist Wilhelm von Wright was sold twice at auctions in Stockholm. The illustration is dated 1834 and shows a specimen that was found dead at the artist's native home, Haminalaks, in Kuopio parish, Central Finland, that year. However, an accurate description of the species had already been made in 1765, by a group of young naturalists on a tour in the Swedish province Dalecarlia.

  • 158.
    Friberg, Magne
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Leimar, O.
    Wiklund, C.
    Heterospecific courtship, minority effects and niche separation between cryptic butterfly species2013In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 26, no 5, p. 971-979Article in journal (Refereed)
    Abstract [en]

    Species interacting in varied ecological conditions often evolve in different directions in different local populations. The butterflies of the cryptic Leptidea complex are sympatrically distributed in different combinations across their Eurasian range. Interestingly, the same species is a habitat generalist in some regions and a habitat specialist in others, where a sibling species has the habitat generalist role. Previous studies suggest that this geographically variable niche divergence is generated by local processes in different contact zones. By varying the absolute and relative densities of Leptidea sinapis and Leptidea juvernica in large outdoor cages, we show that female mating success is unaffected by conspecific density, but strongly negatively affected by the density of the other species. Whereas 80% of the females mated when a conspecific couple was alone in a cage, less than 10% mated when the single couple shared the cage with five pairs of the other species. The heterospecific courtships can thus affect the population fitness, and for the species in the local minority, the suitability of a habitat is likely to depend on the presence or absence of the locally interacting species. If the local relative abundance of the different species depends on the colonization order, priority effects might determine the ecological roles of interacting species in this system.

  • 159.
    Friberg, Magne
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Posledovich, D.
    Wiklund, C.
    Decoupling of female host plant preference and offspring performance in relative specialist and generalist butterflies2015In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 178, no 4, p. 1181-1192Article in journal (Refereed)
    Abstract [en]

    The preference-performance hypothesis posits that the host plant range of plant-feeding insects is ultimately limited by larval costs associated with feeding on multiple resources, and that female egg-laying preferences evolve in response to these costs. The trade-off of either using few host plant species and being a strong competitor on them due to effective utilization or using a wide host plant range but being a poor competitor is further predicted to result in host plant specialization. This follows under the hypothesis that both females and offspring are ultimately favoured by utilizing only the most suitable host(s). We develop an experimental approach to identify such trade-offs, i.e. larval costs associated with being a host generalist, and apply a suite of experiments to two sympatric and syntopic populations of the closely related butterflies Pieris napi and Pieris rapae. These butterflies show variation in their level of host specialization, which allowed comparisons between more and less specialized species and between families within species. Our results show that, first, the link between female host preference and offspring performance was not significantly stronger in the specialist compared to the generalist species. Second, the offspring of the host plant specialist did not outperform the offspring of the generalist on the former's most preferred host plant species. Finally, the more generalized species, or families within species, did not show higher survival or consistently higher growth rates than the specialists on the less preferred plants. Thus, the preference and performance traits appear to evolve as largely separated units.

  • 160.
    Friberg, Magne
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Schwind, Christopher
    Raguso, Robert A.
    Thompson, John N.
    Extreme divergence in floral scent among woodland star species (Lithophragma spp.) pollinated by floral parasites2013In: Annals of Botany, ISSN 0305-7364, E-ISSN 1095-8290, Vol. 111, no 4, p. 539-550Article in journal (Refereed)
    Abstract [en]

    A current challenge in coevolutionary biology is to understand how suites of traits vary as coevolving lineages diverge. Floral scent is often a complex, variable trait that attracts a suite of generalized pollinators, but may be highly specific in plants specialized on attracting coevolved pollinating floral parasites. In this study, floral scent variation was investigated in four species of woodland stars (Lithophragma spp.) that share the same major pollinator (the moth Greya politella, a floral parasite). Three specific hypotheses were tested: (1) sharing the same specific major pollinator favours conservation of floral scent among close relatives; (2) selection favours private channels of rare compounds particularly aimed at the specialist pollinator; or (3) selection from rare, less-specialized co-pollinators mitigates the conservation of floral scent and occurrence of private channels. Dynamic headspace sampling and solid-phase microextraction were applied to greenhouse-grown plants from a common garden as well as to field samples from natural populations in a series of experiments aiming to disentangle the genetic and environmental basis of floral scent variation. Striking floral scent divergence was discovered among species. Only one of 69 compounds was shared among all four species. Scent variation was largely genetically based, because it was consistent across field and greenhouse treatments, and was not affected by visits from the pollinating floral parasite. The strong divergence in floral scents among Lithophragma species contrasts with the pattern of conserved floral scent composition found in other plant genera involved in mutualisms with pollinating floral parasites. Unlike some of these other obligate pollination mutualisms, Lithophragma plants in some populations are occasionally visited by generalist pollinators from other insect taxa. This additional complexity may contribute to the diversification in floral scent found among the Lithophragma species pollinated by Greya moths.

  • 161.
    Friberg, Magne
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Schwind, Christopher
    Roark, Lindsey C.
    Raguso, Robert A.
    Thompson, John N.
    Floral Scent Contributes to Interaction Specificity in Coevolving Plants and Their Insect Pollinators2014In: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 40, no 9, p. 955-965Article in journal (Refereed)
    Abstract [en]

    Chemical defenses, repellents, and attractants are important shapers of species interactions. Chemical attractants could contribute to the divergence of coevolving plant-insect interactions, if pollinators are especially responsive to signals from the local plant species. We experimentally investigated patterns of daily floral scent production in three Lithophragma species (Saxifragaceae) that are geographically isolated and tested how scent divergence affects attraction of their major pollinator the floral parasitic moth Greya politella (Prodoxidae). These moths oviposit through the corolla while simultaneously pollinating the flower with pollen adhering to the abdomen. The complex and species-specific floral scent profiles were emitted in higher amounts during the day, when these day-flying moths are active. There was minimal divergence found in petal color, which is another potential floral attractant. Female moths responded most strongly to scent from their local host species in olfactometer bioassays, and were more likely to oviposit in, and thereby pollinate, their local host species in no-choice trials. The results suggest that floral scent is an important attractant in this interaction. Local specialization in the pollinator response to a highly specific plant chemistry, thus, has the potential to contribute importantly to patterns of interaction specificity among coevolving plants and highly specialized pollinators.

  • 162.
    Friberg, Magne
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Schwind, Christopher
    Univ Calif Santa Cruz, Dept Ecol & Evolutionary Biol, Santa Cruz, CA 95064 USA..
    Thompson, John N.
    Univ Calif Santa Cruz, Dept Ecol & Evolutionary Biol, Santa Cruz, CA 95064 USA..
    Divergence in selection of host species and plant parts among populations of a phytophagous insect2016In: Evolutionary Ecology, ISSN 0269-7653, E-ISSN 1573-8477, Vol. 30, no 4, p. 723-737Article in journal (Refereed)
    Abstract [en]

    The diversification of phytophagous insects is often attributed to diverging processes of host plant specialization onto different, often closely related, host plants. Some insect clades have diversified by specializing not only on different plant species but also on different plant parts of the same hosts. This is the case in Greya moths (Prodoxidae) where both Greya obscura and G. politella are tightly linked to host plants of the genus Lithophragma (Saxifragaceae). We assess how these species differ in their choice of plants and use of plant parts. Previous work showed that strong local host specialization in G. politella is mediated by floral scent variation among Lithophragma species. Here, we identify geographic variation in host plant use in the close relative G. obscura, relate the emerging patterns to previous studies of geographic variation in host use in G. politella and evaluate potential processes underlying the variation among and within species. First, we show that G. obscura also uses floral chemistry to locate hosts but that additional plant cues must be involved in deciding whether to oviposit on a plant, because females did not discriminate against chemically different host species in no-choice trials. We also found that, although all known populations of G. politella oviposit only in flowers, all G. obscura populations examined here distributed their eggs among both floral and scape tissues both in the field and in laboratory experiments. The distribution of eggs among plant parts, however, varied among moth populations, and also depended on the Lithophragma species they attacked. Together, these results show the potential for phytophagous insect species and populations to diverge in use of plant parts as part of the process of speciation and adaptation. These two layers of specialization enhance the potential for subsequent diversification in phytophagous insect lineages.

  • 163.
    Friberg, Magne
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Waters, Mia T.
    Univ Calif Santa Cruz, Dept Ecol & Evolutionary Biol, Santa Cruz, CA 95064 USA..
    Thompson, John N.
    Univ Calif Santa Cruz, Dept Ecol & Evolutionary Biol, Santa Cruz, CA 95064 USA..
    Nutrient availability affects floral scent much less than other floral and vegetative traits in Lithophragma bolanderi2017In: Annals of Botany, ISSN 0305-7364, E-ISSN 1095-8290, Vol. 120, no 3, p. 471-478Article in journal (Refereed)
    Abstract [en]

    Background and Aims: Many plant-pollinator interactions are mediated by floral scents that can vary among species, among populations within species and even among individuals within populations. This variation could be innate and unaffected by the environment, but, because many floral volatiles have amino-acid precursors, scent variation also could be affected by differences in nutrient availability among environments. In plants that have coevolved with specific pollinators, natural selection is likely to favour low phenotypic plasticity in floral scent even under different conditions of nutrient availability if particular scents or scent combinations are important for attracting local pollinators.

    Methods: Clonal pairs of multiple seed-families of two Lithophragma bolanderi (Saxifragaceae) populations were subjected to a high and a low nutrient treatment. These plants are pollinated primarily by host-specific Greya moths. It was evaluated how nutrient treatment affected variation in floral scent relative to other vegetative and reproductive traits.

    Key Results: Floral scent strength (the per-flower emission rate) and composition were unaffected by nutrient treatment, but low-nutrient plants produced fewer and lighter leaves, fewer scapes and fewer flowers than highnutrient plants. The results held in both populations, which differed greatly in the number and composition of floral scents produced.

    Conclusions: The results reveal a strong genetic component both to scent composition and emission level, and partly contrasts with the only previous study that has assessed the susceptibility of floral volatile signals to variation in the abundance of nutrients. These results, and the tight coevolutionary relationship between Lithophragma plants and their specialized Greya moth pollinators, indicate that reproductive traits important to coevolving interactions, such as the floral scent of L. bolanderi, may be locally specialized and more canalized than other traits important for plant fitness.

  • 164.
    Friberg, Magne
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Wiklund, Christer
    Stockholm Univ, Dept Zool, SE-10691 Stockholm, Sweden..
    Butterflies and plants: preference/performance studies in relation to plant size and the use of intact plants vs. cuttings2016In: Entomologia Experimentalis et Applicata, ISSN 0013-8703, E-ISSN 1570-7458, Vol. 160, no 3, p. 201-208Article in journal (Refereed)
    Abstract [en]

    Plants have evolved a number of defences to ameliorate herbivore attacks including chemicals induced by mechanical wounding. Such changes in plant chemical composition are potential confounding factors in experiments on plant-insect interactions, which often present cuttings of potential host plants to phytophagous insects. In particular, this could affect studies of female egg-laying preference and larval performance, because the same plant chemicals that deter certain generalist insects can elevate attacks from more specialized insects. Furthermore, plant cuttings are by definition smaller than intact plants, and any female host size preference could thus affect experiments using plant cuttings. We first assessed female preference and larval performance of a specialist herbivore, Pieris napi (L.) (Lepidoptera: Pieridae, Pierini), confronted with either intact plants or leaf-cuttings of four Brassicaceae host plants, Alliaria petiolata (Bieb.) Cavara & Grande, Barbarea vulgaris (L.) WT Aiton, Berteroa incana (L.) DC., and Brassica napus (L.). Egg and larval survival did not differ between intact plants and leaf-cuttings, whereas larval growth was slightly, but significantly, faster on leaf-cuttings. Females, however, significantly preferred to lay eggs on intact plants of all four hosts, although the preference hierarchy for the intact plants was largely mirrored by that for leaf-cuttings. We then tested the female preference for different size-classes of intact B. napus plants. Small individuals received more eggs than larger individuals, and follow-up experiments showed that this difference was largely generated by a strong female preference for cotyledon leaves; there was no significant difference in female preference for large and small individuals when both carried cotyledons, and females landing on cotyledons were more likely to oviposit compared to when landing on a true leaf. Our study concludes that plant cuttings can serve as adequate proxies for live plants for preference/performance studies, but that experimentalists should be aware of the variation imposed both by plant handling and plant phenology for female oviposition preference.

  • 165. Galeano, C.H.
    et al.
    Cortés, Andres J.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Fernandez, A.C.
    Soler, A.
    Franco-Herrera, N.
    Makunde, G.
    Vanderleyden, J.
    Blair, M.W.
    Gene-based single nucleotide polymorphism markers for genetic and association mapping in common bean2012In: BMC Genetics, ISSN 1471-2156, E-ISSN 1471-2156, Vol. 12, article id 48Article in journal (Refereed)
    Abstract [en]

    Background: In common bean, expressed sequence tags (ESTs) are an underestimated source of gene-based markers such as insertion-deletions (Indels) or single-nucleotide polymorphisms (SNPs). However, due to the nature of these conserved sequences, detection of markers is difficult and portrays low levels of polymorphism. Therefore, development of intron-spanning EST-SNP markers can be a valuable resource for genetic experiments such as genetic mapping and association studies. 

    Results: In this study, a total of 313 new gene-based markers were developed at target genes. Intronic variation was deeply explored in order to capture more polymorphism. Introns were putatively identified after comparing the common bean ESTs with the soybean genome, and the primers were designed over intron-flanking regions. The intronic regions were evaluated for parental polymorphisms using the single strand conformational polymorphism (SSCP) technique and Sequenom MassARRAY system. A total of 53 new marker loci were placed on an integrated molecular map in the DOR364 x G19833 recombinant inbred line (RIL) population. The new linkage map was used to build a consensus map, merging the linkage maps of the BAT93 x JALO EEP558 and DOR364 x BAT477 populations. A total of 1,060 markers were mapped, with a total map length of 2,041 cM across 11 linkage groups. As a second application of the generated resource, a diversity panel with 93 genotypes was evaluated with 173 SNP markers using the MassARRAY-platform and KASPar technology. These results were coupled with previous SSR evaluations and drought tolerance assays carried out on the same individuals. This agglomerative dataset was examined, in order to discover marker-trait associations, using general linear model (GLM) and mixed linear model (MLM). Some significant associations with yield components were identified, and were consistent with previous findings. 

    Conclusions: In short, this study illustrates the power of intron-based markers for linkage and association mapping in common bean. The utility of these markers is discussed in relation with the usefulness of microsatellites, the molecular markers by excellence in this crop.

  • 166.
    Galtier, Nicolas
    et al.
    Univ Montpellier, Inst Sci Evolut, EPHE, CNRS,UMR5554,IRD, Montpellier, France.
    Roux, Camille
    Univ Montpellier, Inst Sci Evolut, EPHE, CNRS,UMR5554,IRD, Montpellier, France; Univ Lausanne, Dept Ecol & Evolut, Lausanne, Switzerland; Univ Lille Sci & Technol, CNRS, UMR Evo Eco Paleo 8198, Villeneuve Dascq, France.
    Rousselle, Marjolaine
    Univ Montpellier, Inst Sci Evolut, EPHE, CNRS,UMR5554,IRD, Montpellier, France.
    Romiguier, Jonathan
    Univ Montpellier, Inst Sci Evolut, EPHE, CNRS,UMR5554,IRD, Montpellier, France; Univ Lausanne, Dept Ecol & Evolut, Lausanne, Switzerland.
    Figuet, Emeric
    Univ Montpellier, Inst Sci Evolut, EPHE, CNRS,UMR5554,IRD, Montpellier, France.
    Glémin, Sylvain
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Univ Montpellier, Inst Sci Evolut, EPHE, CNRS,UMR5554,IRD, Montpellier, France.
    Bierne, Nicolas
    Univ Montpellier, Inst Sci Evolut, EPHE, CNRS,UMR5554,IRD, Montpellier, France.
    Duret, Laurent
    Univ Lyon 1, Univ Lyon, CNRS, Lab Biometrie & Biol Evolut,UMR 5558, Villeurbanne, France.
    Codon Usage Bias in Animals: Disentangling the Effects of Natural Selection, Effective Population Size, and GC-Biased Gene Conversion2018In: Molecular biology and evolution, ISSN 0737-4038, E-ISSN 1537-1719, Vol. 35, no 5, p. 1092-1103Article in journal (Refereed)
    Abstract [en]

    Selection on codon usage bias is well documented in a number of microorganisms. Whether codon usage is also generally shaped by natural selection in large organisms, despite their relatively small effective population size (Ne), is unclear. In animals, the population genetics of codon usage bias has only been studied in a handful of model organisms so far, and can be affected by confounding, nonadaptive processes such as GC-biased gene conversion and experimental artefacts. Using population transcriptomics data, we analyzed the relationship between codon usage, gene expression, allele frequency distribution, and recombination rate in 30 nonmodel species of animals, each from a different family, covering a wide range of effective population sizes. We disentangled the effects of translational selection and GC-biased gene conversion on codon usage by separately analyzing GC-conservative and GC-changing mutations. We report evidence for effective translational selection on codon usage in large-Ne species of animals, but not in small-Ne ones, in agreement with the nearly neutral theory of molecular evolution. C- and T-ending codons tend to be preferred over synonymous G- and A-ending ones, for reasons that remain to be determined. In contrast, we uncovered a conspicuous effect of GC-biased gene conversion, which is widespread in animals and the main force determining the fate of AT↔GC mutations. Intriguingly, the strength of its effect was uncorrelated with Ne.

  • 167.
    Georgolopoulos, Grigorios
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Aristotle Univ Thessaloniki, Sch Biol, Lab Systemat Bot & Phytogeog, POB 104, GR-54124 Thessaloniki, Greece.;Univ Washington, Sch Med, Div Med Genet, 1795 NE Pacific St,Box 357720, Seattle, WA 98195 USA..
    Parducci, Laura
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Drouzas, Andreas D.
    Aristotle Univ Thessaloniki, Sch Biol, Lab Systemat Bot & Phytogeog, POB 104, GR-54124 Thessaloniki, Greece..
    A short phylogenetically informative cpDNA fragment for the identification of Pinus species2016In: Biochemical Systematics and Ecology, ISSN 0305-1978, E-ISSN 1873-2925, Vol. 66, p. 166-172Article in journal (Refereed)
    Abstract [en]

    The genus Pinus L. consists of ca. 110 ecologically and economically important species extending from the arctic zone to the tropics. Nevertheless, there is little information in the literature on DNA-based methods for the identification of pine species. Here, we identified a new cpDNA fragment (trnV-H/x-h) able to differentiate among pine species and correctly depict the phylogeny within the genus. The fragment was identified based on PCR-RFLP profiles and primers designed based on the sequences of six Pinus species naturally occurring in Greece (Pinus brutia Ten., Pinus halepensis Mill., Pinus leucodermis Antoine, Pinus nigra J.F. Arnold, Pinus pinea L, and Pinus sylvestris L). We analyzed 90 highly similar pine sequences retrieved from the GenBank to investigate specificity of our marker and the haplotypes found showed to be specific to Pinus and able to differentiate among 39 different species. The phylogenetic tree constructed using these species, correctly depicted the phylogeny of the genus up to the subsection level. These characteristics together with its relatively small size (376-418 bp) make the trnV-H/x-h marker useful for pine identification even in contexts where DNA is degraded, such as in timber tracing, forensic botany and palaeobotanical investigations.

  • 168. Gerber, Sophie
    et al.
    Chadoeuf, Joel
    Gugerli, Felix
    Lascoux, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Buiteveld, Joukje
    Cottrell, Joan
    Dounavi, Aikaterini
    Fineschi, Silvia
    Forrest, Laura L.
    Fogelqvist, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Goicoechea, Pablo G.
    Jensen, Jan Svejgaard
    Salvini, Daniela
    Vendramin, Giovanni G.
    Kremer, Antoine
    High Rates of Gene Flow by Pollen and Seed in Oak Populations across Europe2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 1, p. e85130-Article in journal (Refereed)
    Abstract [en]

    Gene flow is a key factor in the evolution of species, influencing effective population size, hybridisation and local adaptation. We analysed local gene flow in eight stands of white oak (mostly Quercus petraea and Q. robur, but also Q. pubescens and Q. faginea) distributed across Europe. Adult trees within a given area in each stand were exhaustively sampled (range [239, 754], mean 423), mapped, and acorns were collected ([17,147], 51) from several mother trees ([3,47], 23). Seedlings ([65,387], 178) were harvested and geo-referenced in six of the eight stands. Genetic information was obtained from screening distinct molecular markers spread across the genome, genotyping each tree, acorn or seedling. All samples were thus genotyped at 5-8 nuclear microsatellite loci. Fathers/parents were assigned to acorns and seedlings using likelihood methods. Mating success of male and female parents, pollen and seed dispersal curves, and also hybridisation rates were estimated in each stand and compared on a continental scale. On average, the percentage of the wind-borne pollen from outside the stand was 60%, with large variation among stands (21-88%). Mean seed immigration into the stand was 40%, a high value for oaks that are generally considered to have limited seed dispersal. However, this estimate varied greatly among stands (20-66%). Gene flow was mostly intraspecific, with large variation, as some trees and stands showed particularly high rates of hybridisation. Our results show that mating success was unevenly distributed among trees. The high levels of gene flow suggest that geographically remote oak stands are unlikely to be genetically isolated, questioning the static definition of gene reserves and seed stands.

  • 169. Ghelardini, Luisa
    et al.
    Berlin, Sofia
    Weih, Martin
    Lagercrantz, Ulf
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Gyllenstrand, Niclas
    Ronnberg-Wastljung, Ann Christin y
    Genetic architecture of spring and autumn phenology in Salix2014In: BMC Plant Biology, ISSN 1471-2229, E-ISSN 1471-2229, Vol. 14, p. 31-Article in journal (Refereed)
    Abstract [en]

    Background: In woody plants from temperate regions, adaptation to the local climate results in annual cycles of growth and dormancy, and optimal regulation of these cycles are critical for growth, long-term survival, and competitive success. In this study we have investigated the genetic background to growth phenology in a Salix pedigree by assessing genetic and phenotypic variation in growth cessation, leaf senescence and bud burst in different years and environments. A previously constructed linkage map using the same pedigree and anchored to the annotated genome of P. trichocarpa was improved in target regions and used for QTL analysis of the traits. The major aims in this study were to map QTLs for phenology traits in Salix, and to identify candidate genes in QTL hot spots through comparative mapping with the closely related Populus trichocarpa. Results: All traits varied significantly among genotypes and the broad-sense heritabilities ranged between 0.5 and 0.9, with the highest for leaf senescence. In total across experiment and years, 80 QTLs were detected. For individual traits, the QTLs explained together from 21.5 to 56.5% of the variation. Generally each individual QTL explained a low amount of the variation but three QTLs explained above 15% of the variation with one QTL for leaf senescence explaining 34% of the variation. The majority of the QTLs were recurrently identified across traits, years and environments. Two hotspots were identified on linkage group (LG) II and X where narrow QTLs for all traits co-localized. Conclusions: This study provides the most detailed analysis of QTL detection for phenology in Salix conducted so far. Several hotspot regions were found where QTLs for different traits and QTLs for the same trait but identified during different years co-localised. Many QTLs co-localised with QTLs found in poplar for similar traits that could indicate common pathways for these traits in Salicaceae. This study is an important first step in identifying QTLs and candidate genes for phenology traits in Salix.

  • 170.
    Glemin, Sylvain
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Arndt, Peter F.
    Messer, Philipp W.
    Petrov, Dmitri
    Galtier, Nicolas
    Duret, Laurent
    Quantification of GC-biased gene conversion in the human genome2015In: Genome Research, ISSN 1088-9051, E-ISSN 1549-5469, Vol. 25, no 8, p. 1215-1228Article in journal (Refereed)
    Abstract [en]

    Much evidence indicates that GC-biased gene conversion (gBGC) has a major impact on the evolution of mammalian genomes. However, a detailed quantification of the process is still lacking. The strength of gBGC can be measured from the analysis of derived allele frequency spectra (DAF), but this approach is sensitive to a number of confounding factors. In particular, we show by simulations that the inference is pervasively affected by polymorphism polarization errors and by spatial heterogeneity in gBGC strength. We propose a new general method to quantify gBGC from DAF spectra, incorporating polarization errors, taking spatial heterogeneity into account, and jointly estimating mutation bias. Applying it to human polymorphism data from the 1000 Genomes Project, we show that the strength of gBGC does not differ between hypermutable CpG sites and non-CpG sites, suggesting that in humans gBGC is not caused by the base-excision repair machinery. Genome-wide, the intensity of gBGC is in the nearly neutral area. However, given that recombination occurs primarily within recombination hotspots, 1%-2% of the human genome is subject to strong gBGC. On average, gBGC is stronger in African than in non-African populations, reflecting differences in effective population sizes. However, due to more heterogeneous recombination landscapes, the fraction of the genome affected by strong gBGC is larger in non-African than in African populations. Given that the location of recombination hotspots evolves very rapidly, our analysis predicts that, in the long term, a large fraction of the genome is affected by short episodes of strong gBGC.

  • 171.
    Glemin, Sylvain
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Univ Rennes, CNRS, UMR 6553, ECOBIO Ecosyst Biodiversite Evolut, F-35042 Rennes, France.
    Scornavacca, Celine
    Univ Montpellier, Inst Sci Evolut, CNRS, IRD,EPHE CC 064, Pl Eugene Bataillon, F-34095 Montpellier 05, France.
    Dainat, Jacques
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Burgarella, Concetta
    Univ Montpellier, AGAP, CIRAD, INRA,Montpellier SupAgro, Montpellier, France;CIRAD, UMR AGAP, F-34398 Montpellier, France.
    Viader, Veronique
    Univ Montpellier, AGAP, CIRAD, INRA,Montpellier SupAgro, Montpellier, France.
    Ardisson, Morgane
    Univ Montpellier, AGAP, CIRAD, INRA,Montpellier SupAgro, Montpellier, France.
    Sarah, Gautier
    Univ Montpellier, AGAP, CIRAD, INRA,Montpellier SupAgro, Montpellier, France;INRA, South Green Bioinformat Platform, BIOVERS, CIRAD,IRD,Montpellier SupAgro, Montpellier, France.
    Santoni, Sylvain
    Univ Montpellier, AGAP, CIRAD, INRA,Montpellier SupAgro, Montpellier, France.
    David, Jacques
    Univ Montpellier, AGAP, CIRAD, INRA,Montpellier SupAgro, Montpellier, France.
    Ranwez, Vincent
    Univ Montpellier, AGAP, CIRAD, INRA,Montpellier SupAgro, Montpellier, France.
    Pervasive hybridizations in the history of wheat relatives2019In: Science Advances, E-ISSN 2375-2548, Vol. 5, no 5, article id eaav9188Article in journal (Refereed)
    Abstract [en]

    Cultivated wheats are derived from an intricate history of three genomes, A, B, and D, present in both diploid and polyploid species. It was recently proposed that the D genome originated from an ancient hybridization between the A and B lineages. However, this result has been questioned, and a robust phylogeny of wheat relatives is still lacking. Using transcriptome data from all diploid species and a new methodological approach, our comprehensive phylogenomic analysis revealed that more than half of the species descend from an ancient hybridization event but with a more complex scenario involving a different parent than previously thought-Aegilops mutica, an overlooked wild species-instead of the B genome. We also detected other extensive gene flow events that could explain long-standing controversies in the classification of wheat relatives.

  • 172. Gonzalez-Rivas, B
    et al.
    Tigabu, M
    Gerhardt, Karin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Castro-Marin, G
    Odén, P C
    Species composition, diversity and local uses of tropical dry deciduous and gallery forests in Nicaragua2006In: Biodiversity and Conservation, ISSN 0960-3115, E-ISSN 1572-9710, Vol. 15, no 4, p. 1509-1527Article in journal (Refereed)
    Abstract [en]

    The floristic composition and diversity of tropical dry deciduous and gallery forests were studied in Chacocente Wildlife Refuge, located on the Pacific coast in Nicaragua during 1994 and 2000. Density, dominance and frequency as well as species and family important values were computed to characterize the floristic composition. A variety of diversity measures were also calculated to examine heterogeneity in each forest community. A total of 29 families, 49 genera and 59 species were represented in 2 ha dry deciduous forest. In the gallery forest, the number of families, genera and species recorded in 2000 inventory was 33, 48 and 58, respectively and slightly higher than the 1994 inventory. The number of stems >= 10 cm dbh varied from 451 to 489 per hectare in the deciduous forest, and from 283 to 298 per hectare in the gallery forest. The basal area was much larger for species in the gallery than dry deciduous forest. Fabaceae, sub family Papilionoideae, was the most specious family in the deciduous forest while Meliaceae was the dominant family in the gallery forest. Similarity in species composition and abundance between deciduous and gallery forests was low. In terms of species diversity, the gallery forest was found more diverse than the deciduous forest using Fisher's diversity index. Both forest communities were characterized by a typical inverse J shape. Therefore, emphasis should be given to the protection of rare species, i.e. as the forests are still under continued human pressure, an immediate action should be taken to conserve the remaining flora.

  • 173. González-Martínez, SC
    et al.
    Dillon, S
    Garnier-Géré, P
    Krutovsky, KV
    Alía, R
    Burgarella, C
    Eckert, A
    García-Gil, MR
    Grivet, D
    Heuetz, M
    Jaramillo-Correa, JP
    Lascoux, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Neale, DB
    Savolainen, O
    Tsumura, Y
    Vendramin, GG
    Patterns of Nucleotide Diversity and Association Mapping2011In: Genetics, Genomics and Breeding of Conifers / [ed] Christophe Plomion, Jersey: Science Publishers Inc., 2011, p. 239-275Chapter in book (Refereed)
  • 174.
    Granath, Gustaf
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Peatland Bryophytes in a Changing Environment: Ecophysiological Traits and Ecosystem Function2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Peatlands are peat forming ecosystems in which not fully decomposed plant material builds up the soil. The sequestration of carbon into peat is mainly associated with the bryophyte genus Sphagnum (peat mosses), which dominate and literally form most peatlands. The responses of Sphagnum to environmental change help us to understand peatland development and function and to predict future changes in a rapidly changing world. In this thesis, the overarching aim was to use ecophysiological traits to investigate mechanisms behind the response of Sphagnum to elevated N deposition, and, processes connected to ecosystem shift and ecosystem function of peatlands.

    Regarding elevated N deposition, three experiments were performed at different scales (country-wide to greenhouse). Independent of scale and species, apical tissue N concentration increased with increasing N input until N saturation was reached. Maximum photosynthetic rate, a trait evaluating photosynthetic capacity, increased with N input and could be well predicted by tissue N concentration. Thus, the physiological responses of Sphagnum to N deposition are often positive and I found no evidence of toxic effects. Production did, however, not increase with N input, and results of the N:P ratio suggested that P limitation, and possibly other elements, might hamper growth under high N input. The effect of P limitation was, in contrast to current view, most pronounced in fast growing species indicating species specific responses to nutrient imbalance.

    I explored the puzzling, but historically frequently occurring, rich fen to bog ecosystem shift; a shift from a species-rich ecosystem dominated by brown mosses, to a species-poor one with greater carbon storage that is Sphagnum-dominated. The bog-dwelling species of Sphagnum grew well, to our surprise, when in contact with rich fen water but was not a strong competitor compared to rich fen Sphagnum species. If submerged under rich fen water (high pH), the bog Sphagnum species died while rich fen species of Sphagnum were unaffected. These results show that differences in two physiological traits (growth rate and tolerance to flooding) among species, can explain when a peatland ecosystem shift might occur.

    In the last study, the function of peatlands was related to trade-offs between traits and allometric scaling in Sphagnum. Results suggested that growth strategies are determined by the distribution of Sphagnum relative to the water table in order to minimize periods with suboptimal hydration. Allometric analyses stressed the importance of resource allocation among and within shoots (apical part vs. stem), although the allocation patterns in Sphagnum were not always consistent with those of vascular plants. Interestingly, data indicated a trade-off between photosynthetic rate and decomposition rate among Sphagnum species.

    List of papers
    1. Photosynthetic performance in Sphagnum transplanted along a latitudinal nitrogen deposition gradient
    Open this publication in new window or tab >>Photosynthetic performance in Sphagnum transplanted along a latitudinal nitrogen deposition gradient
    Show others...
    2009 (English)In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 159, no 4, p. 705-715Article in journal (Refereed) Published
    Abstract [en]

    Increased N deposition in Europe has affected mire ecosystems. However, knowledge on the physiological responses is poor. We measured photosynthetic responses to increasing N deposition in two peatmoss species (Sphagnum balticum and Sphagnum fuscum) from a 3-year, north-south transplant experiment in northern Europe, covering a latitudinal N deposition gradient ranging from 0.28 g N m(-2) year(-1) in the north, to 1.49 g N m(-2) year(-1) in the south. The maximum photosynthetic rate (NPmax) increased southwards, and was mainly explained by tissue N concentration, secondly by allocation of N to the   photosynthesis, and to a lesser degree by modified photosystem II activity (variable fluorescence/maximum fluorescence yield). Although climatic factors may have contributed, these results were most likely attributable to an increase in N deposition southwards. For S. fuscum, photosynthetic rate continued to increase up to a deposition level of 1.49 g N m(-2) year(-1), but for S. balticum it seemed to level out at 1.14 g N m(-2) year(-1). The results for S. balticum suggested that transplants from different origin (with low or intermediate N   deposition) respond differently to high N deposition. This indicates that Sphagnum species may be able to adapt or physiologically adjust to high N deposition. Our results also suggest that S. balticum might be more sensitive to N deposition than S. fuscum. Surprisingly, NPmax was not (S. balticum), or only weakly (S. fuscum) correlated with biomass production, indicating that production is to a great extent is governed by factors other than the photosynthetic capacity.

    Keywords
    Chlorophyll fluorescence, Chlorophyll, Carbon dioxide exchange, Photosynthesis, Peatlands
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:uu:diva-120352 (URN)10.1007/s00442-008-1261-1 (DOI)000264103800003 ()
    Available from: 2010-03-11 Created: 2010-03-11 Last updated: 2019-02-01Bibliographically approved
    2. Physiological responses to nitrogen and sulphur addition and raised temperature in Sphagnum balticum
    Open this publication in new window or tab >>Physiological responses to nitrogen and sulphur addition and raised temperature in Sphagnum balticum
    2009 (English)In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 161, no 3, p. 481-490Article in journal (Refereed) Published
    Abstract [en]

    Sphagnum, the main genus which forms boreal peat, is strongly affected by N and S deposition and raised temperature, but the physiological mechanisms behind the responses are largely unknown. We measured maximum photosynthetic rate (NPmax), maximum efficiency of photosystem II [variable fluorescence (F v)/maximum fluorescence yield (F m)] and concentrations of N, C, chlorophyll and carotenoids as responses to N and S addition and increased temperature in Sphagnum balticum (a widespread species in the northern peatlands) in a 12-year factorial experiment. NPmax did not differ between control (0.2 g N m−2 year−1) and high N (3.0 g N m−2 year−1), but was higher in the mid N treatment (1.5 g N m−2 year−1). N, C, carotenoids and chlorophyll concentration increased in shoot apices after N addition. F v/F m did not differ between N treatments. Increased temperature (+3.6°C) had a small negative effect on N concentration, but had no significant effect on NPmax or F v/F m. Addition of 2 g S m−2 year−1 showed a weak negative effect on NPmax and F v/F m. Our results suggest a unimodal response of NPmax to N addition and tissue N concentration in S. balticum, with an optimum N concentration for photosynthetic rate of ~13 mg N g−1. In conclusion, high S deposition may reduce photosynthetic capacity in Sphagnum, but the negative effects may be relaxed under high N availability. We suggest that previously reported negative effects on Sphagnum productivity under high N deposition are not related to negative effects on the photosynthetic apparatus, but differences in optimum N concentration among Sphagnum species may affect their competitive ability under different N deposition regimes.

    Keywords
    Chlorophyll fluorescence, Nutrient deposition, Peatlands, Photosynthesis, Photosynthetic nitrogen use efficiency
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:uu:diva-120447 (URN)10.1007/s00442-009-1406-x (DOI)000269010300004 ()19593588 (PubMedID)
    Available from: 2010-03-12 Created: 2010-03-12 Last updated: 2017-12-12Bibliographically approved
    3. Direct physiological effects of nitrogen on Sphagnum: a greenhouse experiment
    Open this publication in new window or tab >>Direct physiological effects of nitrogen on Sphagnum: a greenhouse experiment
    2012 (English)In: Functional Ecology, ISSN 0269-8463, E-ISSN 1365-2435, Vol. 26, no 2, p. 353-364Article in journal (Refereed) Published
    Abstract [en]

    1. Bogs are nutrient-poor peatland ecosystems that are sensitive to nitrogen (N) deposition. Production of peat mosses (i.e. the peat-forming genus Sphagnum) is known to decrease under elevated N deposition, but the causal mechanisms are poorly understood. 2. It is predicted that increased N deposition will cause changes in Sphagnum species composition, with fast-growing species benefiting from increased N availability in contrast to slow-growing species. Knowledge of species-specific responses to N availability can help us to understand interspecific competitive relationships. 3. We investigated the direct effects of N application on plant physiology in three Sphagnum species by exposing shoots to a range of N doses (corresponding to depositions of 0-5 6 g m) 2 year) 1), over 5 months, in a greenhouse experiment. The species investigated included one that grows high above the water-table (Sphagnum fuscum) and two that grow lower down (Sphagnum balticum and Sphagnum fallax). S. fuscum and S. balticum originate from ombrotrophic and S. fallax from minerotrophic environments. To estimate N responses, we measured the performance and light-capture kinetics of the photosynthetic apparatus (maximum photosynthetic rate and Fv/Fm), biomass production, shoot formation, and N and phosphorus (P) concentrations in the tissue. 4. Tissue nitrogen concentration generally increased with N application rate, and photosynthetic rate increased with N concentration, although S. balticum exhibited a unimodal response. With respect to production, a negative response to N application rate was found in S. fallax and S. fuscum (weak), while production in S. balticum was unrelated to application rate. S. fallax was the fastest-growing species, producing two to three times more biomass per shoot compared with the other species. 5. The mismatch between photosynthetic capacity and production could partly be explained by an increased N : P ratio following N application. Phosphorus limitation may not negatively affect photosynthetic capacity, but may hamper production. 6. The fast-growing species S. fallax is considered to benefit from increased N deposition, but we found a negative physiological response, suggesting stoichiometric constraints. Thus, we conclude that responses to N deposition cannot be predicted in a simple way from physiological traits related to growth rate without considering local environmental factors. 

    National Category
    Ecology
    Research subject
    Ecological Botany
    Identifiers
    urn:nbn:se:uu:diva-165127 (URN)10.1111/j.1365-2435.2011.01948.x (DOI)000302011400007 ()
    Available from: 2012-01-03 Created: 2012-01-03 Last updated: 2019-02-01Bibliographically approved
    4. Rapid ecosystem shifts in peatlands: Linking plant physiology and succession
    Open this publication in new window or tab >>Rapid ecosystem shifts in peatlands: Linking plant physiology and succession
    2010 (English)In: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 91, no 10, p. 3047-3056Article in journal (Refereed) Published
    Abstract [en]

    Stratigraphic records from peatlands suggest that the shift from a rich fen (calcareous fen) to an ombrotrophic bog can occur rapidly. This shift constitutes a switch from a species-rich ecosystem to a species-poor one with greater carbon storage. In this process, the invasion and expansion of acidifying bog species of Sphagnum (peat mosses) play a key role. To test under what conditions an acidifying bog species could invade a rich fen, we conducted three experiments, contrasting the bog species S. fucsum with the rich-fen species S. warnstorfii and S. teres. We first tested the effect of calcareous water by growing the three species at different constant height above the water table (HWT; 2, 7, and 14 cm) in a rich-fen pool and measured maximum photosynthetic rate and production and difference in length growth as an indicator of competition. In none of the species was the photosynthetic capacity negatively affected when placed at low HWT, but S. fuscum was a weaker competitor at low HWT. In our second experiment we transplanted the three species into microhabitats with different and naturally varying HWT in a rich fen. Here, S. fuscum nearly ceased to photosynthesize when transplanted to low HWT (brown moss carpet), while it performed similarly to the two rich-fen species at the intermediate level (S. warnstorfii hummock level). In contrast to S. fuscum, the rich-fen sphagna performed equally well in both habitats. The brown moss carpet was seasonally flooded, and in our third experiment we found that S. fuscum, but not S. teres, was severely damaged when submerged in rich-fen water. Our results suggest two thresholds in HWT affecting the ecosystem switch: one level that reduces the risk of submergence and a higher one that makes bog sphagna competitive against the rich-fen species.

    Keywords
    Allogenic succession; Bog; Calcareous; Catastrophic shift; Competition; Drought, Flooding, Hällefjärd, Mire, Ombrotrophication, Photosynthesis, Sphagnum spp, Sweden
    National Category
    Biological Sciences
    Research subject
    Biology with specialization in Ecological Botany
    Identifiers
    urn:nbn:se:uu:diva-143269 (URN)10.1890/09-2267.1 (DOI)000282654700023 ()
    Available from: 2011-01-20 Created: 2011-01-20 Last updated: 2019-02-01Bibliographically approved
    5. Functional traits in Sphagnum, allometry, and their impacts on carbon cycling in peatlands
    Open this publication in new window or tab >>Functional traits in Sphagnum, allometry, and their impacts on carbon cycling in peatlands
    Show others...
    (English)Manuscript (preprint) (Other academic)
    National Category
    Ecology
    Research subject
    Ecological Botany
    Identifiers
    urn:nbn:se:uu:diva-165131 (URN)
    Available from: 2012-01-03 Created: 2012-01-03 Last updated: 2015-04-20
  • 175.
    Granath, Gustaf
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Rydin, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Baltzer, Jennifer L.
    Biology Department, Wilfrid Laurier University, Waterloo, Canada.
    Bengtsson, Fia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Boncek, Nicholas
    Department of Biological Sciences, Union College, Schenectady, NY, USA.
    Bragazza, Luca
    Department of Life Science and Biotechnologies, University of Ferrara, Ferrara, Italy; Swiss Federal Institute for Forest, Snow and Landscape Research, WSL Site Lausanne, Station 2, Lausanne, Switzerland; Ecole Polytechnique Fédérale de Lausanne EPFL, School of Architecture, Civil and Environmental Engineering ENAC, Laboratory of ecological systems ECOS, Station 2, Lausanne, Switzerland.
    Bu, Zhao-Jun
    Institute for Peat and Mire Research, Northeast Normal University, State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, Changchun, China; Jilin Provincial Key Laboratory for Wetland Ecological Processes and Environmental Change in the Changbai Mountains, Changchun, China.
    Caporn, Simon J. M.
    School of Science and the Environment, Division of Biology and Conservation Ecology, Manchester Metropolitan University, Manchester, UK.
    Dorrepaal, Ellen
    Climate Impacts Research Centre, Dept. of Ecology and Environmental Science, Umeå University, Abisko, Sweden.
    Galanina, Olga
    Institute of Earth Sciences, St. Petersburg State University, St. Petersburg, Russia; Komarov Botanical Institute Russian Academy of Sciences, St. Petersburg, Russia.
    Galka, Mariusz
    Laboratory of Wetland Ecology and Monitoring & Department of Biogeography and Paleoecology, Adam Mickiewicz University in Poznan, Poznan, Polen.
    Ganeva, Anna
    Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, Sofia, Bulgaria.
    Gillikin, David P.
    Department of Geology, Union College, Schenectady, NY, USA.
    Goia, Irina
    Babe ̧s-Bolyai University, Faculty of Biology and Geology, Department of Taxonomy and Ecology, Cluj Napoca, Romania.
    Goncharova, Nadezhda
    Institute of Biology of Komi Scientific Centre of the Ural Branch of the Russian Academy of Science, Syktyvkar, Russia.
    Hajek, Michal
    Masaryk Univ, Fac Sci, Dept Bot & Zool, Brno, Czech Republic.
    Haraguchi, Akira
    Univ Kitakyushu, Dept Biol, Kitakyushu, Fukuoka, Japan.
    Harris, Lorna I.
    McGill Univ, Dept Geog, Montreal, Canada.
    Humphreys, Elyn
    Carleton Univ, Dept Geog & Environm Studies, Ottawa, Canada.
    Jirousek, Martin
    Masaryk Univ, Fac Sci, Dept Bot & Zool, Brno, Czech Republic; Mendel Univ Brno, Fac AgriSci, Dept Plant Biol, Brno, Czech Republic.
    Kajukalo, Katarzyna
    Adam Mickiewicz Univ, Lab Wetland Ecol & Monitoring, Poznan, Poland; Adam Mickiewicz Univ, Dept Biogeog & Paleoecol, Poznan, Poland.
    Karofeld, Edgar
    Univ Tartu, Inst Ecol & Earth Sci, Tartu, Estonia.
    Koronatova, Natalia G.
    Russian Acad Sci, Siberian Branch, Inst Soil Sci & Agrochem, Lab Biogeocenol, Novosibirsk, Russia.
    Kosykh, Natalia P.
    Russian Acad Sci, Siberian Branch, Inst Soil Sci & Agrochem, Lab Biogeocenol, Novosibirsk, Russia.
    Lamentowicz, Mariusz
    Adam Mickiewicz Univ, Lab Wetland Ecol & Monitoring, Poznan, Poland; Adam Mickiewicz Univ, Dept Biogeog & Paleoecol, Poznan, Poland.
    Lapshina, Elena
    Yugra State Univ, Khanty Mansiysk, Russia.
    Limpens, Juul
    Wageningen Univ, Plant Ecol & Nat Conservat Grp, Wageningen, Netherlands.
    Linkosalmi, Maiju
    Finnish Meteorol Inst, Helsinki, Finland.
    Ma, Jin-Ze
    Northeast Normal Univ, State Environm Protect Key Lab Wetland Ecol & Veg, Inst Peat & Mire Res, Changchun, Jilin, Peoples R China; Jilin Prov Key Lab Wetland Ecol Proc & Environm C, Changchun, Jilin, Peoples R China.
    Mauritz, Marguerite
    No Arizona Univ, Dept Biol Sci, Ctr Ecosyst Sci & Soc Ecoss, Flagstaff, USA.
    Munir, Tariq M.
    Univ Calgary, Dept Geog, Calgary, Canada; St Marys Univ, Dept Geol, Calgary, Canada.
    Natali, Susan M.
    Woods Hole Res Ctr, Falmouth, USA.
    Natcheva, Rayna
    Bulgarian Acad Sci, Inst Biodivers & Ecosyst Res, Sofia, Bulgaria.
    Noskova, Maria
    Russian Acad Sci, Komarov Bot Inst, St Petersburg, Russia.
    Payne, Richard J.
    Univ York, Environm, York, N Yorkshire, England; Penza State Univ, Penza, Russia.
    Pilkington, Kyle
    Union Coll, Dept Biol Sci, Schenectady, NY USA.
    Robinson, Sean
    SUNY Coll Oneonta, Dept Biol, Oneonta, NY USA.
    Robroek, Bjorn J. M.
    Univ Southampton, Biol Sci, Southampton, Hants, England.
    Rochefort, Line
    Laval Univ, Dept Plant Sci, Quebec City, PQ, Canada; Laval Univ, Ctr Northern Studies, Quebec City, PQ, Canada.
    Singer, David
    Univ Neuchatel, Inst Biol, Lab Soil Biodivers, Neuchatel, Switzerland; Univ Sao Paulo, Inst Biosci, Dept Zool, Sao Paulo, Brazil.
    Stenoien, Hans K.
    Norwegian Univ Sci & Technol, NTNU Univ Museum, Trondheim, Norway.
    Tuittila, Eeva-Stiina
    Univ Eastern Finland, Sch Forest Sci, Peatland & Soil Ecol Grp, Joensuu, Finland.
    Vellak, Kai
    Univ Tartu, Inst Ecol & Earth Sci, Tartu, Estonia.
    Verheyden, Anouk
    Union Coll, Dept Geol, Schenectady, NY USA.
    Waddington, James Michael
    McMaster Univ, Sch Geog & Earth Sci, Hamilton, Canada.
    Rice, Steven K.
    Union Coll, Dept Biol Sci, Schenectady, NY USA.
    Environmental and taxonomic controls of carbon and oxygen stable isotope composition in Sphagnum across broad climatic and geographic ranges2018In: Biogeosciences, ISSN 1726-4170, E-ISSN 1726-4189, Vol. 15, no 16, p. 5189-5202Article in journal (Refereed)
    Abstract [en]

    Rain-fed peatlands are dominated by peat mosses (Sphagnum sp.), which for their growth depend on nutrients, water and CO2 uptake from the atmosphere. As the isotopic composition of carbon (C-12(,)13) and oxygen (O-16(,)18) of these Sphagnum mosses are affected by environmental conditions, Sphagnum tissue accumulated in peat constitutes a potential long-term archive that can be used for climate reconstruction. However, there is inadequate understanding of how isotope values are influenced by environmental conditions, which restricts their current use as environmental and palaeoenvironmental indicators. Here we tested (i) to what extent C and O isotopic variation in living tissue of Sphagnum is speciesspecific and associated with local hydrological gradients, climatic gradients (evapotranspiration, temperature, precipitation) and elevation; (ii) whether the C isotopic signature can be a proxy for net primary productivity (NPP) of Sphagnum; and (iii) to what extent Sphagnum tissue delta O-18 tracks the delta O-18 isotope signature of precipitation. In total, we analysed 337 samples from 93 sites across North America and Eurasia us ing two important peat-forming Sphagnum species (S. magellanicum, S. fuscum) common to the Holarctic realm. There were differences in delta C-13 values between species. For S. magellanicum delta C-13 decreased with increasing height above the water table (HWT, R-2 = 17 %) and was positively correlated to productivity (R-2 = 7 %). Together these two variables explained 46 % of the between-site variation in delta C-13 values. For S. fuscum, productivity was the only significant predictor of delta C-13 but had low explanatory power (total R-2 = 6 %). For delta O-18 values, approximately 90 % of the variation was found between sites. Globally modelled annual delta O-18 values in precipitation explained 69 % of the between-site variation in tissue delta O-18. S. magellanicum showed lower delta O-18 enrichment than S. fuscum (-0.83 %0 lower). Elevation and climatic variables were weak predictors of tissue delta O-18 values after controlling for delta O-18 values of the precipitation. To summarize, our study provides evidence for (a) good predictability of tissue delta O-18 values from modelled annual delta O-18 values in precipitation, and (b) the possibility of relating tissue delta C-13 values to HWT and NPP, but this appears to be species-dependent. These results suggest that isotope composition can be used on a large scale for climatic reconstructions but that such models should be species-specific.

  • 176.
    Granath, Gustaf
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Strengbom, Joachim
    Swedish University of Agricultural Sciences.
    Rydin, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Direct physiological effects of nitrogen on Sphagnum: a greenhouse experiment2012In: Functional Ecology, ISSN 0269-8463, E-ISSN 1365-2435, Vol. 26, no 2, p. 353-364Article in journal (Refereed)
    Abstract [en]

    1. Bogs are nutrient-poor peatland ecosystems that are sensitive to nitrogen (N) deposition. Production of peat mosses (i.e. the peat-forming genus Sphagnum) is known to decrease under elevated N deposition, but the causal mechanisms are poorly understood. 2. It is predicted that increased N deposition will cause changes in Sphagnum species composition, with fast-growing species benefiting from increased N availability in contrast to slow-growing species. Knowledge of species-specific responses to N availability can help us to understand interspecific competitive relationships. 3. We investigated the direct effects of N application on plant physiology in three Sphagnum species by exposing shoots to a range of N doses (corresponding to depositions of 0-5 6 g m) 2 year) 1), over 5 months, in a greenhouse experiment. The species investigated included one that grows high above the water-table (Sphagnum fuscum) and two that grow lower down (Sphagnum balticum and Sphagnum fallax). S. fuscum and S. balticum originate from ombrotrophic and S. fallax from minerotrophic environments. To estimate N responses, we measured the performance and light-capture kinetics of the photosynthetic apparatus (maximum photosynthetic rate and Fv/Fm), biomass production, shoot formation, and N and phosphorus (P) concentrations in the tissue. 4. Tissue nitrogen concentration generally increased with N application rate, and photosynthetic rate increased with N concentration, although S. balticum exhibited a unimodal response. With respect to production, a negative response to N application rate was found in S. fallax and S. fuscum (weak), while production in S. balticum was unrelated to application rate. S. fallax was the fastest-growing species, producing two to three times more biomass per shoot compared with the other species. 5. The mismatch between photosynthetic capacity and production could partly be explained by an increased N : P ratio following N application. Phosphorus limitation may not negatively affect photosynthetic capacity, but may hamper production. 6. The fast-growing species S. fallax is considered to benefit from increased N deposition, but we found a negative physiological response, suggesting stoichiometric constraints. Thus, we conclude that responses to N deposition cannot be predicted in a simple way from physiological traits related to growth rate without considering local environmental factors. 

  • 177.
    Granath, Gustaf
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Strengbom, Joachim
    Rydin, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Rapid ecosystem shifts in peatlands: Linking plant physiology and succession2010In: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 91, no 10, p. 3047-3056Article in journal (Refereed)
    Abstract [en]

    Stratigraphic records from peatlands suggest that the shift from a rich fen (calcareous fen) to an ombrotrophic bog can occur rapidly. This shift constitutes a switch from a species-rich ecosystem to a species-poor one with greater carbon storage. In this process, the invasion and expansion of acidifying bog species of Sphagnum (peat mosses) play a key role. To test under what conditions an acidifying bog species could invade a rich fen, we conducted three experiments, contrasting the bog species S. fucsum with the rich-fen species S. warnstorfii and S. teres. We first tested the effect of calcareous water by growing the three species at different constant height above the water table (HWT; 2, 7, and 14 cm) in a rich-fen pool and measured maximum photosynthetic rate and production and difference in length growth as an indicator of competition. In none of the species was the photosynthetic capacity negatively affected when placed at low HWT, but S. fuscum was a weaker competitor at low HWT. In our second experiment we transplanted the three species into microhabitats with different and naturally varying HWT in a rich fen. Here, S. fuscum nearly ceased to photosynthesize when transplanted to low HWT (brown moss carpet), while it performed similarly to the two rich-fen species at the intermediate level (S. warnstorfii hummock level). In contrast to S. fuscum, the rich-fen sphagna performed equally well in both habitats. The brown moss carpet was seasonally flooded, and in our third experiment we found that S. fuscum, but not S. teres, was severely damaged when submerged in rich-fen water. Our results suggest two thresholds in HWT affecting the ecosystem switch: one level that reduces the risk of submergence and a higher one that makes bog sphagna competitive against the rich-fen species.

  • 178.
    Gros-Balthazard, Muriel
    et al.
    Univ Montpellier, Montpellier SupAgro, INRA, CIRAD,AGAP, Montpellier, France;NYUAD, Ctr Genom & Syst Biol, Abu Dhabi, U Arab Emirates.
    Besnard, Guillaume
    CNRS UPS IRD, UMR5174, Lab EDB, Toulouse, France.
    Sarah, Gautier
    Univ Montpellier, Montpellier SupAgro, INRA, CIRAD,AGAP, Montpellier, France.
    Holtz, Yan
    Univ Montpellier, Montpellier SupAgro, INRA, CIRAD,AGAP, Montpellier, France.
    Leclercq, Julie
    Univ Montpellier, Montpellier SupAgro, INRA, CIRAD,AGAP, Montpellier, France.
    Santoni, Sylvain
    Univ Montpellier, Montpellier SupAgro, INRA, CIRAD,AGAP, Montpellier, France.
    Wegmann, Daniel
    Univ Fribourg, Dept Biol, Fribourg, Switzerland;Swiss Inst Bioinformat, Fribourg, Switzerland.
    Glemin, Sylvain
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Univ Rennes, CNRS, ECOBIO Ecosyst Biodiversite Evolut UMR 6553, F-35000 Rennes, France;.
    Khadari, Bouchaib
    Univ Montpellier, Montpellier SupAgro, INRA, CIRAD,AGAP, Montpellier, France;UMR AGAP, Conservatoire Bot Natl Mediterraneen, Montpellier, France.
    Evolutionary transcriptomics reveals the origins of olives and the genomic changes associated with their domestication2019In: The Plant Journal, ISSN 0960-7412, E-ISSN 1365-313X, Vol. 100, no 1, p. 143-157Article in journal (Refereed)
    Abstract [en]

    The olive (Olea europaea L. subsp. europaea) is one of the oldest and most socio-economically important cultivated perennial crop in the Mediterranean region. Yet, its origins are still under debate and the genetic bases of the phenotypic changes associated with its domestication are unknown. We generated RNA-sequencing data for 68 wild and cultivated olive trees to study the genetic diversity and structure both at the transcription and sequence levels. To localize putative genes or expression pathways targeted by artificial selection during domestication, we employed a two-step approach in which we identified differentially expressed genes and screened the transcriptome for signatures of selection. Our analyses support a major domestication event in the eastern part of the Mediterranean basin followed by dispersion towards the West and subsequent admixture with western wild olives. While we found large changes in gene expression when comparing cultivated and wild olives, we found no major signature of selection on coding variants and weak signals primarily affected transcription factors. Our results indicated that the domestication of olives resulted in only moderate genomic consequences and that the domestication syndrome is mainly related to changes in gene expression, consistent with its evolutionary history and life history traits.

  • 179.
    Gyllenstrand, Niclas
    et al.
    Växtbiologi och skogsgenetik, Plant Biology and Forest Genetics.
    Karlgren, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Clapham, David
    Växtbiologi och skogsgenetik, Plant Biology and Forest Genetics.
    Holm, Karl
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Hall, Anthony
    Gould, Peter D.
    Källman, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Lagercrantz, Ulf
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    No time for spruce: rapid dampening of circadian rhythms in Picea abies (L. Karst)2014In: Plant and Cell Physiology, ISSN 0032-0781, E-ISSN 1471-9053, Vol. 55, no 3, p. 535-550Article in journal (Refereed)
  • 180.
    Hagenblad, Jenny
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Zie, Jenny
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Leino, Matti W.
    Exploring the population genetics of genebank and historical landrace varieties2012In: Genetic Resources and Crop Evolution, ISSN 0925-9864, E-ISSN 1573-5109, Vol. 59, no 6, p. 1185-1199Article in journal (Refereed)
    Abstract [en]

    Landrace accessions have long been recognized as an important source of genetic diversity for crop species, and landraces are stored in genebanks across the world as genetic resources for future crop development. Landraces are also an important part of the human cultural heritage and as such they have been used for genetic studies to make inferences about historical agriculture. However, surprisingly little is known about the within-accession diversity of landrace crops of different species. In order to evaluate the diversity of Swedish landraces we used microsatellite markers to genotype accessions of four species (barley, pea, oats and rye), both extant genebank material and 114-year-old seed samples of similar geographic origin and type. We found consistently high levels of within-population genetic diversity in the historical material, but varying and often lower diversity levels in the genebank accessions. We also make tentative conclusions about how representative the genebank material is to what was originally cultivated in its reported area of origin and suggest that the true identity of the genebank accessions is unclear and that historical seed collections should be a more appropriate material for the study of historical agriculture.

  • 181.
    Halbritter, Aud H.
    et al.
    Univ Bergen, Dept Biol Sci, Post Box 7803, N-5020 Bergen, Norway;ETH, Inst Integrat Biol, Zurich, Switzerland.
    Fior, Simone
    ETH, Inst Integrat Biol, Zurich, Switzerland.
    Keller, Irene
    Univ Bern, Dept Clin Res, Bern, Switzerland;Univ Bern, Swiss Inst Bioinformat, Bern, Switzerland.
    Billeter, Regula
    ZHAW Wadenswil, Inst Nat Resource Sci, Wadenswil, Switzerland.
    Edwards, Peter J.
    ETH, Inst Integrat Biol, Zurich, Switzerland.
    Holderegger, Rolf
    ETH, Inst Integrat Biol, Zurich, Switzerland;Swiss Fed Res Inst Forest Snow & Landscape WSL, Birmensdorf, Switzerland.
    Karrenberg, Sophie
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Pluess, Andrea R.
    Swiss Fed Res Inst Forest Snow & Landscape WSL, Birmensdorf, Switzerland.
    Widmer, Alex
    ETH, Inst Integrat Biol, Zurich, Switzerland.
    Alexander, Jake M.
    ETH, Inst Integrat Biol, Zurich, Switzerland;Univ Lausanne, Dept Ecol & Evolut, Lausanne, Switzerland.
    Trait differentiation and adaptation of plants along elevation gradients2018In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 31, no 6, p. 784-800Article, review/survey (Refereed)
    Abstract [en]

    Studies of genetic adaptation in plant populations along elevation gradients in mountains have a long history, but there has until now been neither a synthesis of how frequently plant populations exhibit adaptation to elevation nor an evaluation of how consistent underlying trait differences across species are. We reviewed studies of adaptation along elevation gradients (i) from a meta-analysis of phenotypic differentiation of three traits (height, biomass and phenology) from plants growing in 70 common garden experiments; (ii) by testing elevation adaptation using three fitness proxies (survival, reproductive output and biomass) from 14 reciprocal transplant experiments; (iii) by qualitatively assessing information at the molecular level, from 10 genomewide surveys and candidate gene approaches. We found that plants originating from high elevations were generally shorter and produced less biomass, but phenology did not vary consistently. We found significant evidence for elevation adaptation in terms of survival and biomass, but not for reproductive output. Variation in phenotypic and fitness responses to elevation across species was not related to life history traits or to environmental conditions. Molecular studies, which have focussed mainly on loci related to plant physiology and phenology, also provide evidence for adaptation along elevation gradients. Together, these studies indicate that genetically based trait differentiation and adaptation to elevation are widespread in plants. We conclude that a better understanding of the mechanisms underlying adaptation, not only to elevation but also to environmental change, will require more studies combining the ecological and molecular approaches.

  • 182.
    Hallingback, Henrik R.
    et al.
    Swedish Univ Agr Sci, Uppsala BioCtr, Dept Plant Biol, POB 7043, S-75007 Uppsala, Sweden.;Linnean Ctr Plant Biol, POB 7043, S-75007 Uppsala, Sweden..
    Fogelqvist, Johan
    Swedish Univ Agr Sci, Uppsala BioCtr, Dept Plant Biol, POB 7043, S-75007 Uppsala, Sweden.;Linnean Ctr Plant Biol, POB 7043, S-75007 Uppsala, Sweden..
    Powers, Stephen J.
    Rothamsted Res, Computat & Syst Biol Dept, Harpenden AL5 2JQ, Herts, England..
    Turrion-Gomez, Juan
    Rothamsted Res, AgroEcol Dept, Harpenden AL5 2JQ, Herts, England..
    Rossiter, Rachel
    Rothamsted Res, AgroEcol Dept, Harpenden AL5 2JQ, Herts, England..
    Amey, Joanna
    Rothamsted Res, AgroEcol Dept, Harpenden AL5 2JQ, Herts, England..
    Martin, Tom
    Swedish Univ Agr Sci, Uppsala BioCtr, Dept Plant Biol, POB 7043, S-75007 Uppsala, Sweden.;Linnean Ctr Plant Biol, POB 7043, S-75007 Uppsala, Sweden..
    Weih, Martin
    Linnean Ctr Plant Biol, POB 7043, S-75007 Uppsala, Sweden.;Swedish Univ Agr Sci, Dept Crop Prod Ecol, POB 7043, S-75007 Uppsala, Sweden..
    Gyllenstrand, Niclas
    Swedish Univ Agr Sci, Uppsala BioCtr, Dept Plant Biol, POB 7043, S-75007 Uppsala, Sweden.;Linnean Ctr Plant Biol, POB 7043, S-75007 Uppsala, Sweden..
    Karp, Angela
    Rothamsted Res, AgroEcol Dept, Harpenden AL5 2JQ, Herts, England..
    Lagercrantz, Ulf
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Hanley, Steven J.
    Rothamsted Res, AgroEcol Dept, Harpenden AL5 2JQ, Herts, England..
    Berlin, Sofia
    Swedish Univ Agr Sci, Uppsala BioCtr, Dept Plant Biol, POB 7043, S-75007 Uppsala, Sweden.;Linnean Ctr Plant Biol, POB 7043, S-75007 Uppsala, Sweden..
    Roennberg-Wastljung, Ann-Christin
    Swedish Univ Agr Sci, Uppsala BioCtr, Dept Plant Biol, POB 7043, S-75007 Uppsala, Sweden.;Linnean Ctr Plant Biol, POB 7043, S-75007 Uppsala, Sweden..
    Association mapping in Salix viminalis L. (Salicaceae) - identification of candidate genes associated with growth and phenology2016In: Global Change Biology Bioenergy, ISSN 1757-1693, E-ISSN 1757-1707, Vol. 8, no 3, p. 670-685Article in journal (Refereed)
    Abstract [en]

    Willow species (Salix) are important as short-rotation biomass crops for bioenergy, which creates a demand for faster genetic improvement and breeding through deployment of molecular marker-assisted selection (MAS). To find markers associated with important adaptive traits, such as growth and phenology, for use in MAS, we genetically dissected the trait variation of a Salix viminalis (L.) population of 323 accessions. The accessions were sampled throughout northern Europe and were established at two field sites in Pustnas, Sweden, and at Woburn, UK, offering the opportunity to assess the impact of genotype-by-environment interactions (GxE) on trait-marker associations. Field measurements were recorded for growth and phenology traits. The accessions were genotyped using 1536 SNP markers developed from phenology candidate genes and from genes previously observed to be differentially expressed in contrasting environments. Association mapping between 1233 of these SNPs and the measured traits was performed taking into account population structure and threshold selection bias. At a false discovery rate (FDR) of 0.2, 29 SNPs were associated with bud burst, leaf senescence, number of shoots or shoot diameter. The percentage of accession variation explained by these associations ranged from 0.3% to 4.4%, suggesting that the studied traits are controlled by many loci of limited individual impact. Despite this, a SNP in the EARLY FLOWERING 3 gene was repeatedly associated (FDR<0.2) with bud burst. The rare homozygous genotype exhibited 0.4-1.0 lower bud burst scores than the other genotype classes on a five-grade scale. Consequently, this marker could be promising for use in MAS and the gene deserves further study. Otherwise, associations were less consistent across sites, likely due to their small estimates and to considerable GxE interactions indicated by multivariate association analyses and modest trait accession correlations across sites (0.32-0.61).

  • 183.
    Hantemirova, E. V.
    et al.
    Russian Acad Sci, Inst Plant & Anim Ecol, Ural Branch, 8 Marta Str,202, Ekaterinburg 620144, Russia..
    Heinze, B.
    Austrian Fed Res Ctr Forests, Dept Forest Genet, Seckendorff Gudent Weg 8, A-1130 Vienna, Austria..
    Knyazeva, S. G.
    Russian Acad Sci, Forest Inst, Siberian Branch, Krasnojarsk Akademgorodo 660036, Russia..
    Musaev, A. M.
    Russian Acad Sci, Dagestan Sci Ctr, Mt Bot Garden, 45 M Gadgiev St, Makhachkala 367000, Republic Of Dag, Russia..
    Lascoux, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Semerikov, V. L.
    Russian Acad Sci, Inst Plant & Anim Ecol, Ural Branch, 8 Marta Str,202, Ekaterinburg 620144, Russia..
    A new Eurasian phylogeographical paradigm?: Limited contribution of southern populations to the recolonization of high latitude populations in Juniperus communis L.(Cupressaceae)2017In: Journal of Biogeography, ISSN 0305-0270, E-ISSN 1365-2699, Vol. 44, no 2, p. 271-282Article in journal (Refereed)
    Abstract [en]

    AimThe aims of this population genetics study of the common juniper across Eurasia were to (1) assess the contribution of southern mountain ranges to the post-glacial recolonization of high latitudes and (2) test whether recent expansion or high gene flow could explain the low genetic differentiation in Northern Eurasia. LocationNorthern Eurasia and mountain regions of Central Europe and Asia. MethodsSix hundred and twenty-two individuals were sampled in 42 populations. Two chloroplast DNA (cpDNA) fragments were investigated (trnT-trnL and 16S-trnA). Analyses of the distribution of haplotypes across the continent included a suite of phylogeographical and phylogenetic tests. Putative geographical distribution in the past was reconstructed using environmental niche modelling. ResultsEighty-four haplotypes clustered into four main clades (GL1-GL4). The largest clade, GL3, corresponds to populations from the Alps, northern Europe, Western Caucasus and Siberia. These populations were moderately differentiated (28%) compared to the total range (76%) and Fu's F-s statistic was negative, indicating a population expansion. Some haplotypes within GL3 form subclades with a restricted geographical distribution, suggesting a local origin of the mutation and limited dispersal. In line with these findings, modelling of ecological niches found no significant reduction in the expected range during the LGM. Remarkably, populations from the eastern part of North Caucasus, the Himalayas, Tien Shan and south Siberia were distinctly different from populations in the rest of the range. Main conclusionsAs in Siberian larch species, the pattern of genetic diversity at cpDNA across the natural range of J. communis suggests that colonization of northern Europe and Siberia started from a limited area and predated the last glaciation. It is likely that juniper survived the subsequent glacial epoch at high latitudes in cryptic refugia serving as secondary centres of recolonization. Southern mountain refugia contribution to the recolonization of high latitudes was, at best, limited.

  • 184.
    Hartfield, Matthew
    et al.
    Univ Toronto, Dept Ecol & Evolut Biol, Toronto, ON M5S 3B2, Canada.;Aarhus Univ, Bioinformat Res Ctr, DK-8000 Aarhus C, Denmark..
    Bataillon, Thomas
    Aarhus Univ, Bioinformat Res Ctr, DK-8000 Aarhus C, Denmark..
    Glemin, Sylvain
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Univ Montpellier, CNRS, EPHE, Inst Sci Evolut,IRD,ISEM,UMR 5554, Pl Eugene Bataillon, F-34075 Montpellier, France.
    The Evolutionary Interplay between Adaptation and Self-Fertilization2017In: Trends in Genetics, ISSN 0168-9525, E-ISSN 1362-4555, Vol. 33, no 6, p. 420-431Article, review/survey (Refereed)
    Abstract [en]

    Genome-wide surveys of nucleotide polymorphisms, obtained from next-generation sequencing, have uncovered numerous examples of adaptation in self-fertilizing organisms, especially regarding changes to climate, geography, and reproductive systems. Yet existing models for inferring attributes of adaptive mutations often assume idealized outcrossing populations, which risks mis-characterizing properties of these variants. Recent theoretical work is emphasizing how various aspects of self-fertilization affects adaptation, yet empirical data on these properties are lacking. We review theoretical and empirical studies demonstrating how self-fertilization alters the process of adaptation, illustrated using examples from current sequencing projects. We propose ideas for how future research can more accurately quantify aspects of adaptation in self-fertilizers, including incorporating the effects of standing variation, demographic history, and polygenic adaptation.

  • 185.
    Hartfield, Matthew
    et al.
    CNRS, Inst Rech Dev 224, UM1, UM2,UMR 5290,Lab Malad Infect & Vecteurs Ecol Gen, F-34394 Montpellier 05, France.;Univ Toronto, Dept Ecol & Evolutionary Biol, Toronto, ON M5S 3B2, Canada.;Univ Aarhus, Bioinformat Res Ctr, DK-8000 Aarhus C, Denmark..
    Glemin, Sylvain
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. CNRS, Inst Sci Evolut Montpellier, UMR 5554, F-34095 Montpellier 5, France..
    Limits to Adaptation in Partially Selfing Species2016In: Genetics, ISSN 0016-6731, E-ISSN 1943-2631, Vol. 203, no 2, p. 959-+Article in journal (Refereed)
    Abstract [en]

    In outcrossing populations, "Haldane's sieve" states that recessive beneficial alleles are less likely to fix than dominant ones, because they are less exposed to selection when rare. In contrast, selfing organisms are not subject to Haldane's sieve and are more likely to fix recessive types than outcrossers, as selfing rapidly creates homozygotes, increasing overall selection acting on mutations. However, longer homozygous tracts in selfers also reduce the ability of recombination to create new genotypes. It is unclear how these two effects influence overall adaptation rates in partially selfing organisms. Here, we calculate the fixation probability of beneficial alleles if there is an existing selective sweep in the population. We consider both the potential loss of the second beneficial mutation if it has a weaker advantage than the first one, and the possible replacement of the initial allele if the second mutant is fitter. Overall, loss of weaker adaptive alleles during a first selective sweep has a larger impact on preventing fixation of both mutations in highly selfing organisms. Furthermore, the presence of linked mutations has two opposing effects on Haldane's sieve. First, recessive mutants are disproportionally likely to be lost in outcrossers, so it is likelier that dominant mutations will fix. Second, with elevated rates of adaptive mutation, selective interference annuls the advantage in selfing organisms of not suffering from Haldane's sieve; outcrossing organisms are more able to fix weak beneficial mutations of any dominance value. Overall, weakened recombination effects can greatly limit adaptation in selfing organisms.

  • 186. Hedberg, Petter
    et al.
    Kotowski, Wiktor
    Saetre, Peter
    Mälson, Kalle
    Rydin, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Sundberg, Sebastian
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Vegetation recovery after multiple-site experimental fen restorations2012In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 147, no 1, p. 60-67Article in journal (Refereed)
    Abstract [en]

    Large peatland areas have been drained for forestry and agricultural purposes, resulting in the decline of characteristic biodiversity. Two measures commonly suggested for restoring drained fens is ditch blocking and tree removal to raise the groundwater table and increase light availability, respectively. In 2002, we initiated factorial restoration experiments, including ditch blocking and tree removal, in three former rich fens that had been drained for forestry purposes. Species cover of vascular plants and bryophytes were monitored during 8 years in permanent plots along transects perpendicular to the ditch for all four treatment combinations. Both methods had positive and independent effects on the cover of wetland vegetation. Specifically, Sphagnum species and wetland bryophytes showed a persistent positive response to both clear cutting and rewetting. Wetland vascular plants and grasses showed a persistent positive response to clear cutting. Sedges and species number responded positively to both clear cutting and ditch blocking, but the response was partly transient, and for species richness the response was limited when restoration methods were applied separately. Rich fen indicators of vascular plants and bryophytes did not respond to any of the restoration treatments. This indicates that species introduction in combination with further habitat restorations may be necessary to re-establish the original rich fen flora. Nevertheless, we conclude that the combination of ditch blocking and clear cutting are effective measures to partly restore wetland vegetation on previously drained and forested fens, while peat subsidence along the ditch may restrict the success further away from ditches.

  • 187. Hedberg, Petter
    et al.
    Saetre, Peter
    Sundberg, Sebastian
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Rydin, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Kotowski, Wiktor
    A functional trait approach to fen restoration analysis2013In: Applied Vegetation Science, ISSN 1402-2001, E-ISSN 1654-109X, Vol. 16, no 4, p. 658-666Article in journal (Refereed)
    Abstract [en]

    Questions: Ecological restoration has traditionally been evaluated with analyses focused on species identities and abundances. These analyses provide no ecological explanation to why certain species change in abundance. One solution may be a functional trait analysis. We asked whether shifts in functional traits could explain vegetation changes in fens restored through tree cutting and rewetting, and how the functional traits in the restored sites compare to those of the reference site? Location: Three former rich fens in east-central Sweden. Methods: Tree cutting and rewetting were applied in a factorial design, and species and abundance data were recorded for 8yrs. Abundance data and trait data of canopy height, specific leaf area (SLA) and diaspore mass were used to calculate functional richness (FRic), functional divergence (FDiv), functional dispersion (FDis) and community-weighted mean (CWM) of functional traits. Data were analysed in a linear mixed effect model for vascular plants and bryophytes jointly, and for vascular plants separately. Results of restoration treatments were compared to data from a reference site. Results: Among vascular plants, tree cutting caused a decrease in SLA, as shade-sensitive species increased. In accordance with the change in SLA, FDis increased. In the joint analysis, tree cutting led to increased FDis, FDiv and FRic, indicating reduced filtering caused by the removal of the shading canopy, which allowed shade-sensitive species to establish. The comparison to the reference site shows that even after 8yrs, the restoration treatments have higher trait diversity than the reference site, indicating that the restoration sites have a too relaxed trait filter compared to conditions in an undisturbed fen. Our interpretation is that this is primarily caused by insufficient rewetting (and increased nutrient availability) that allow species of both natural and degraded fen conditions to co-exist, and which failed to suppress the regrowth of trees. Conclusions: Analysis of functional diversity improves our understanding of the ecological mechanisms affecting restoration results, and allows comparison among regions and communities with different species composition.

  • 188. Hedenäs, L.
    et al.
    Herben, T.
    Rydin, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Söderström, L.
    Ecology of the invading moss species Orthodontium lineare in Sweden: Spatial distribution and population structure1989In: Holarctic Ecology, Vol. 12, p. 163-172Article in journal (Refereed)
  • 189. Hedenäs, L.
    et al.
    Herben, T.
    Rydin, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Söderström, L.
    Ecology of the invading moss species Orthodontium lineare in Sweden: substrate preference and interactions with other species1989In: Journal of Bryology, Vol. 15, p. 565-581Article in journal (Refereed)
  • 190. Hedenås, Henrik
    et al.
    Carlsson, Bengt Å.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Emanuelsson, Urban
    Headley, Alistair D.
    Jonasson, Christer
    Svensson, Brita M.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Callaghan, Terry V.
    Changes Versus Homeostasis in Alpine and Sub-Alpine Vegetation Over Three Decades in the Sub-Arctic2012In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 41, no Suppl 3, p. 187-196Article in journal (Refereed)
    Abstract [en]

    Plant species distributions are expected to shift and diversity is expected to decline as a result of global climate change, particularly in the Arctic where climate warming is amplified. We have recorded the changes in richness and abundance of vascular plants at Abisko, sub-Arctic Sweden, by re-sampling five studies consisting of seven datasets; one in the mountain birch forest and six at open sites. The oldest study was initiated in 1977-1979 and the latest in 1992. Total species number increased at all sites except for the birch forest site where richness decreased. We found no general pattern in how composition of vascular plants has changed over time. Three species, Calamagrostis lapponica, Carex vaginata and Salix reticulata, showed an overall increase in cover/frequency, while two Equisetum taxa decreased. Instead, we showed that the magnitude and direction of changes in species richness and composition differ among sites.

  • 191.
    Hedwall, Per-Ola
    et al.
    Swedish Univ Agr Sci, Southern Swedish Forest Res Ctr, Sundsvagen 3, SE-23053 Alnarp, Sweden..
    Brunet, Jörg
    Swedish Univ Agr Sci, Southern Swedish Forest Res Ctr, Sundsvagen 3, SE-23053 Alnarp, Sweden..
    Rydin, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Peatland plant communities under global change: negative feedback loops counteract shifts in species composition2017In: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 98, no 1, p. 150-161Article in journal (Refereed)
    Abstract [en]

    Mires (bogs and fens) are nutrient-limited peatland ecosystems, the vegetation of which is especially sensitive to nitrogen deposition and climate change. The role of mires in the global carbon cycle, and the delivery of different ecosystem services can be considerably altered by changes in the vegetation, which has a strong impact on peat-formation and hydrology. Mire ecosystems are commonly open with limited canopy cover but both nitrogen deposition and increased temperatures may increase the woody vegetation component. It has been predicted that such an increase in tree cover and the associated effects on light and water regimes would cause a positive feed-back loop with respect to the ground vegetation. None of these effects, however, have so far been confirmed in large-scale spatiotemporal studies. Here we analyzed data pertaining to mire vegetation from the Swedish National Forest Inventory collected from permanent sample plots over a period of 20 yr along a latitudinal gradient covering 14 degrees. We hypothesized that the changes would be larger in the southern parts as a result of higher nitrogen deposition and warmer climate. Our results showed an increase in woody vegetation with increases in most ericaceous dwarf-shrubs and in the basal area of trees. These changes were, in contrast to our expectations, evenly distributed over most of the latitudinal gradient. While nitrogen deposition is elevated in the south, the increase in temperatures during recent decades has been larger in the north. Hence, we suggest that different processes in the north and south have produced similar vegetation changes along the latitudinal gradient. There was, however, a sharp increase in compositional change at high deposition, indicating a threshold effect in the response. Instead of a positive feed-back loop caused by the tree layer, an increase in canopy cover reduced the changes in composition of the ground vegetation, whereas a decrease in canopy cover lead to larger changes. Increased natural disturbances of the tree layer due to, for example, pathogens or climate is a predicted outcome of climate change. Hence, these results may have important implications for predictions of long-term effects of increased temperature on peatland vegetation.

  • 192.
    Hemborg, Åsa M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Despres, Laurence
    Floral phenotypic plasticity as a buffering mechanism in the globeflower-fly mutualism2011In: Plant Ecology, ISSN 1385-0237, E-ISSN 1573-5052, Vol. 212, no 7, p. 1205-1212Article in journal (Refereed)
    Abstract [en]

    A buffering mechanism in co-evolutionary relationships could be to display phenotypic plasticity in response to environmental changes. In the nursery pollination mutualism between the European globeflower and its exclusive fly pollinators, adults feed and mate in flowers, and larvae develop feeding on seeds. Flower number and size influence fitness for both partners, and large flowers attract more flies. We tested floral plasticity in plants from two contrasting environments: a high-altitude heath and low- and intermediate-altitude meadow forests. High-altitude plants have single flowers, while meadow-forest plants sometimes have multiple flowers. Plants were grown for 3 years in a garden and supplied with eight times more nutrients than available in natural soils, given to controls. During the experiment, over 90% of all plants with excess nutrients flowered, while in controls, 40% (high-altitude) to 75-78% (meadow-forest) plants flowered. Excess nutrients stimulated 30% larger flowers, and in meadow-forest plants flower number increased 4.5-5 times. Flower number was only doubled in high-altitude plants. High-altitude plants displayed less plasticity, and possibly, a different genetic strategy involving meristem limitation.

  • 193.
    Henriksson, Olle
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Biotic interactions along a latitudinal gradient: Field study of the perennial herb Primula farinosa2019Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Because climatic factors may differentially limit the distribution of plants, herbivores, and pollinators, the intensity of biotic interactions is expected to vary geographically. To determine if the intensity of biotic interactions varied along a latitudinal gradient or with population size in the perennial herb Primula farinosa, 31 populations were studied across the Swedish range of the species from latitude 56°N to 63°N. Populations were visited during flowering and fruit maturation. Intensities of grazing (proportion of plants grazed), pollination (proportion of flowers initiating fruit development), seed predation (proportion of initiated fruits consumed by seed predators), and smut infection (proportion of initiated fruit infected by smut) were recorded as well as flower production and reproductive output (number of intact mature fruits). While all tested variables varied between populations, the intensities of biotic interactions were not significantly related to latitude or population size. Number of flowers produced per plant decreased with increasing latitude, whereas the proportion of flowers developing into a mature fruit tended to be higher at the ends than in the central part of the latitudinal gradient. Grazing damage was higher and fruit set (proportion of flowers developing into intact mature fruits) lower at sites exposed to domestic grazers than at sites without domestic grazers. The results suggest that while abiotic factors limit the number of flowers a plant produce and resources decrease with increasing latitude, antagonistic biotic interactions supress seed production mainly in the central part of the geographic range in Sweden. This might be explained by edge populations escaping antagonists mainly located in the centre of the species distribution.

  • 194. Herben, T.
    et al.
    Rydin, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Söderström, L.
    Spore establishment probability and the persistence of the fugitive invading moss, Orthodontium lineare: a spatial simulation model1991In: Oikos, Vol. 60, p. 215-221Article in journal (Refereed)
  • 195.
    Herrera, Andrea
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Changes in spatial structure of woody savanna vegetation after 11 years of exclusion of large herbivores2011Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
  • 196. Hilmo, Olga
    et al.
    Ely-Aastrup, Hilde
    Hytteborn, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Holien, Håkon
    Population characteristics of old forest associated epiphytic lichens in Picea abies plantations in the boreal rainforest of Central Norway2011In: Canadian Journal of Forest Research, ISSN 0045-5067, E-ISSN 1208-6037, Vol. 41, no 9, p. 1743-1753Article in journal (Refereed)
    Abstract [en]

    The boreal rainforest in Central Norway is rich in rare and (or) red-listed epiphytic lichens but is subject to forest harvesting. Natural old Picea abies (L.) H. Karst. forests have been replaced increasingly by dense, even-aged plantations. This study aims at increasing our knowledge about populations of old forest associated lichens in P. abies plantations. In differently aged plantations, we measured occurrence of six lichen species and the population size and reproductive effort of :five lichen species. We found that the success of colonizing plantations differed because of species-specific constraints and needs, and that species occurrence depended on stand age and branch quality. A high number of reproducing thalli and small juvenile thalli of the cyanolichen Lobaria scrobiculata (Scop.) DC. and the pendulous lichen Ramalina thrausta (Ach.) Nyl. suggest effective recruitment within plantations. The populations of the cyanolichens Lobaria pulmonaria (L.) Hoffm. and Pseudocphellaria crocata (L.) Vain, were too small to be viable and demand special concern to survive in managed forests. The abundance of old forest associated lichens in a managed boreal rainforest could be promoted by a varied and heterogeneous branch structure, increased rotation periods (increase the value of plantations as propagule sources), small clearcuts and retention trees (shorten the distance between sources of propagules and target substrate), and maintaining Salix and Sorbus trees (important host trees for cyanolichens and thereby important dispersal sources).

  • 197. Hofgaard, Annika
    et al.
    Lokken, Jørn O.
    Dalen, Linda
    Hytteborn, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Comparing warming and grazing effects on birch growth in an alpine environment: a 10-year experiment2010In: Plant Ecology & Diversity, ISSN 1755-0874, E-ISSN 1755-1668, Vol. 3, no 1, p. 19-27Article in journal (Refereed)
    Abstract [en]

    Background : Tree encroachment of arctic tundra and alpine vegetation is a generally predicted response to climate warming. However, herbivory plays an important role in structuring these ecosystems and their responses to warming.

    Aims : To experimentally test how grazing and increased growing season temperature influence growth, physiognomy and stature of birch in the alpine zone.

    Methods: Trait responses of naturally regenerated birch saplings to warming (open-top chambers), and changed grazing regime (exclosures) were compared with those growing in unmanipulated conditions over a 10-year period (1999–2008). The effect of treatment over time and differences between treatments were analysed with repeated measures GLM (Generalised Linear Model) and simple contrasts in GLM.

    Results: Warming alone had no major effect on trait responses, however, significantly smaller leaves and an increased number of short shoots indicated warming-related growth constraints. Grazing showed a strong controlling effect on most traits, conserving low stature sapling stage characterised by fewer shoots and larger leaves, compared with non-grazed treatments.

    Conclusions: Although derived from one experimental site, the results point to a grazing-controlled response to environmental change, with climate (warming) as a secondary driver. This herbivore-driven masking of expected climate-driven tree expansion emphasises the necessity to consider changes in grazing regimes along with climate change, in order to avoid misleading interpretations regarding climate-driven tundra encroachment.

  • 198.
    Holm, Karl
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Perceptions of the Concept of Evolution among Undergraduate Biology Students2014In: EARLI Special Interest Group 9. Phenomenography and Variation Theory: Disciplinary knowledge and Necessary Conditions of Learning, University of Oxford, 2014, p. 15-15Conference paper (Refereed)
    Abstract [en]

    The concept of evolution is central to biology. As empirical and natural phenomena, evolution and evolutionary processes constitute the primary study objects for a number of disciplines within the biological field of study. Furthermore, the concept comprises the fundamental cornerstone in the theoretical framework, the theory of evolution, which is assumed to unite all of the life sciences. It may therefore be worthwhile to attempt to describe in detail what conceptional variations in the understanding of the term that may exist among students in biology. In this study, written responses were collected from students attending the Bachelor Programme in Biology at Uppsala University during 2012. The responses were subjected to a reading aimed at elucidating qualitatively different categories of understanding and the interrelationship of these categories. The theoretical underpinnings of this reading have been inspired by hermeneutics and theoretical developments of phenomenography. The findings outline qualitatively different notions of the concept of evolution that ranges from definitions of an isolated entity to more sophisticated evaluations that reveal an interest in discussing the limits and validity of evolutionary explanations within and outside the scientific domain.

  • 199.
    Horner, Ariel A.
    et al.
    Univ Cent Florida, Dept Biol, Orlando, FL 32816 USA..
    Hoffman, Eric A.
    Univ Cent Florida, Dept Biol, Orlando, FL 32816 USA..
    Tye, Matthew R.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Hether, Tyler D.
    Univ Oregon, Inst Ecol & Evolut, Eugene, OR 97403 USA..
    Savage, Anna E.
    Univ Cent Florida, Dept Biol, Orlando, FL 32816 USA..
    Cryptic chytridiomycosis linked to climate and genetic variation in amphibian populations of the southeastern United States2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 4, article id e175843Article in journal (Refereed)
    Abstract [en]

    North American amphibians have recently been impacted by two major emerging pathogens, the fungus Batrachochytrium dendrobatidis (Bd) and iridoviruses in the genus Ranavirus (Rv). Environmental factors and host genetics may play important roles in disease dynamics, but few studies incorporate both of these components into their analyses. Here, we investigated the role of environmental and genetic factors in driving Bd and Rv infection prevalence and severity in a biodiversity hot spot, the southeastern United States. We used quantitative PCR to characterize Bd and Rv dynamics in natural populations of three amphibian species: Notophthalmus perstriatus, Hyla squirella and Pseudacris ornata. We combined pathogen data, genetic diversity metrics generated from neutral markers, and environmental variables into general linear models to evaluate how these factors impact infectious disease dynamics. Occurrence, prevalence and intensity of Bd and Rv varied across species and populations, but only one species, Pseudacris ornata, harbored high Bd intensities in the majority of sampled populations. Genetic diversity and climate variables both predicted Bd prevalence, whereas climatic variables alone predicted infection intensity. We conclude that Bd is more abundant in the southeastern United States than previously thought and that genetic and environmental factors are both important for predicting amphibian pathogen dynamics. Incorporating both genetic and environmental information into conservation plans for amphibians is necessary for the development of more effective management strategies to mitigate the impact of emerging infectious diseases.

  • 200.
    Huang, Hui-Run
    et al.
    Chinese Acad Sci, South China Bot Garden, Key Lab Plant Resources Conservat & Sustainable U, Guangzhou 510650, Guangdong, Peoples R China;Chinese Acad Sci, Guangdong Prov Key Lab Appl Bot, South China Bot Garden, Guangzhou 510650, Guangdong, Peoples R China.
    Liu, Jia-Jia
    Chinese Acad Sci, South China Bot Garden, Key Lab Plant Resources Conservat & Sustainable U, Guangzhou 510650, Guangdong, Peoples R China;Chinese Acad Sci, Guangdong Prov Key Lab Appl Bot, South China Bot Garden, Guangzhou 510650, Guangdong, Peoples R China.
    Xu, Yong
    Chinese Acad Sci, South China Bot Garden, Key Lab Plant Resources Conservat & Sustainable U, Guangzhou 510650, Guangdong, Peoples R China;Chinese Acad Sci, Guangdong Prov Key Lab Appl Bot, South China Bot Garden, Guangzhou 510650, Guangdong, Peoples R China.
    Lascoux, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Ge, Xue-Jun
    Chinese Acad Sci, South China Bot Garden, Key Lab Plant Resources Conservat & Sustainable U, Guangzhou 510650, Guangdong, Peoples R China;Chinese Acad Sci, Guangdong Prov Key Lab Appl Bot, South China Bot Garden, Guangzhou 510650, Guangdong, Peoples R China.
    Wright, Stephen I.
    Univ Toronto, Dept Ecol & Evolutionary Biol, Toronto, ON M5S 3B2, Canada.
    Homeologue-specific expression divergence in the recently formed tetraploid Capsella bursa-pastoris (Brassicaceae)2018In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 220, no 2, p. 624-635Article in journal (Refereed)
    Abstract [en]

    Following allopolyploid formation, extensive genome evolution occurs, with the eventual loss of many homeologous gene copies. Although this process of diploidization has occurred many times independently, the evolutionary forces determining the probability and rate of gene loss remain poorly understood. Here, we conduct genome and transcriptome sequencing in a broad sample of Chinese accessions of Capsella bursa-pastoris, a recently formed allotetraploid. Our whole genome data reveal three groups of these accessions: an Eastern group from low-altitude regions, a Western group from high-altitude regions, and a much more differentiated Northwestern group. Population differentiation in total expression was limited among closely related populations; by contrast, the relative expression of the two homeologous copies closely mirrors the genome-wide SNP divergence. Consistent with this, we observe a negative correlation between expression changes in the two homeologues. However, genes showing population genomic evidence for adaptive evolution do not show an enrichment for expression divergence between homeologues, providing no clear evidence for adaptive shifts in relative gene expression. Overall, these patterns suggest that neutral drift may contribute to the population differentiation in the expression of the homeologues, and drive eventual gene loss over longer periods of time.

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