Sökning: "flowering phenology"

Visar resultat 1 - 5 av 22 avhandlingar innehållade orden flowering phenology.

  1. 1. Plant phenology in seasonal environments

    Författare :Elsa Fogelström; Johan Ehrlén; Johan P. Dahlgren; Arthur Weis; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Autumn phenology; Cardamine pratensis; evolutionary ecology; heritability; herbivore preference; fitness components; flowering time; growing season length; life-history; Lathyrus vernus; natural selection; population differentiation; phenology; spring phenology; Plant Ecology; växtekologi;

    Sammanfattning : Phenology, or the seasonal timing life-history events such as emergence, reproduction and senescence will determine the outcome of interactions between plants and both abiotic and biotic aspects of the environment. Such timing is therefore of utmost importance for plants in seasonal environments. LÄS MER

  2. 2. Plant-Animal Interactions and Evolution of Floral Display and Flowering Phenology in Arabidopsis lyrata

    Författare :Saskia Sandring; Jon Ågren; Johan Ehrlén; José Gómez; Uppsala universitet; []
    Nyckelord :Ecology; Arabidopsis lyrata; natural selection; floral display; phenology; flowering time; plant-animal interactions; pollination; herbivory; selection gradients; population differentiation; local adaptation; Ekologi;

    Sammanfattning : In this thesis, I combined comparative and experimental approaches to examine selection on reproductive traits, and population differentiation in the insect-pollinated, outcrossing, perennial herb Arabidopsis lyrata. More specifically, I (1) determined whether selection on flowering phenology and floral display can be attributed to interactions with pollinators and herbivores, (2) examined whether population differentiation in flowering phenology and floral display is correlated with current selection on these traits, and (3) tested for local adaptation from contrasting environments in Europe. LÄS MER

  3. 3. Life History and Tolerance and Resistance against Herbivores in Natural Populations of Arabidopsis thaliana

    Författare :Reiko Akiyama; Jon Ågren; Arjen Biere; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Arabidopsis thaliana; life history evolution; flowering time; germination; phenology; plant-herbivore interactions; natural selection; tolerance to leaf damage; resistance to herbivory; Plutella xylostella; Mamestra brassicae; Biology with specialization in Ecological Botany; Biologi med inriktning mot ekologisk botanik;

    Sammanfattning : In this thesis, I combined observational studies with field and greenhouse experiments to examine selection on life history traits and variation in tolerance and resistance against herbivores in natural populations of the annual herb Arabidopsis thaliana in its native range. I investigated (1) phenotypic selection on flowering time and plant size, (2) the effects of timing of germination on plant fitness, (3) the effect of leaf damage on seed production, and (4) correlations between resistance against a specialist and a generalist insect herbivore. LÄS MER

  4. 4. Population Differentiation in Solidago virgaurea along Altitudinal Gradients

    Författare :Anna Bergsten; Jon Ågren; Staffan Karlsson; Kari Lehtilä; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; population differentiation; altitudinal gradient; plant nutrient status; resorption efficiency; resorption proficiency; flowering phenology; countergradient variation; reproductive effort; flower production; cost of reproduction; Biology; Biologi; Other biology; Övrig biologi; Ecological Botany; Ekologisk botanik;

    Sammanfattning : Altitudinal gradients offer attractive opportunities for studies of population differentiation in response to environmental heterogeneity. In this thesis, I examined population differentiation along altitudinal gradients by combining common-garden experiments with field studies and experiments in alpine, subalpine and boreal populations of the perennial herb Solidago virgaurea. LÄS MER

  5. 5. Temperature and the synchrony of plant-insect interactions

    Författare :Tenna Toftegaard; Johan Ehrlén; Karl Gotthard; Christer Wiklund; Annette Menzel; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Brassicaceae; Anthocharis cardamines; climate change; development; oviposition; phenology; species interactions; herbivory; synchrony; timing; phenotypic plasticity; local adaptation; Plant Ecology; växtekologi;

    Sammanfattning : Increasing temperatures resulting from climate change have within recent years been shown to advance phenological events in a large number of species worldwide. Species can differ in their response to increasing temperatures, and understanding the mechanisms that determine the response is therefore of great importance in order to understand and predict how a warming climate can influence both individual species, but also their interactions with each other and the environment. LÄS MER