Sökning: "leaf size"
Visar resultat 1 - 5 av 38 avhandlingar innehållade orden leaf size.
1. Comparative morphological studies of fossil and living plane trees (Platanaceae) and oaks (Quercus): taxonomy, ecology, evolution
Sammanfattning : Morphological characters are essential for flowering plant identification, but also provide information about diversity patterns and ecological adaptation. In woody plant species, characters of the leaf are among the most useful and can be examined on fossils as well. LÄS MER
Sammanfattning : A procedure for the preparation of spinach leaf mitochondria was developed. The procedure combines differential centrifugation, partition in dextran- polyethyleneglycol two-phase system and Percoli density gradient centri- fugation. The different steps separate the material mainly according to size, surface properties and density, respectively. LÄS MER
Sammanfattning : Phosphorus is an essential element for all living organisms and is central to the genetics and energetics of life. Inorganic phosphate (Pi) is recurrently involved in protein regulation and signal transduction but also in energy transfer as a component of the ATP-molecule. LÄS MER
4. Plant-Herbivore Interactions and Evolutionary Potential of Natural Arabidopsis lyrata Populations
Sammanfattning : In this thesis, I combined field, greenhouse and common-garden experiments to examine the ecological and evolutionary consequences of plant-herbivore interactions and the genetic architecture of fitness-related traits in the insect-pollinated, self-incompatible, perennial herb Arabidopsis lyrata. More specifically, I examined (1) whether damage to leaves and inflorescences affects plant fitness non-additively, (2) whether trichome production is associated with a cost in terms of reduced tolerance to leaf and inflorescence damage, (3) whether young plant resistance to a specialist insect herbivore varies among populations, and (4) whether the evolution of flowering time, floral display and rosette size is constrained by lack of genetic variation or by genetic correlations among traits. LÄS MER
Sammanfattning : This thesis focuses on mechanisms and processes underlying spatial patterns of resistance and virulence and on local adaptations in plant–parasite interactions. The model system used comprises the plant host Salix triandra, the pathogenic rust fungus Melampsora amygdalinae, the leaf beetle Gonioctena linnaeana, and the galler Pontania triandrae. LÄS MER