Search for dissertations about: "leaf herbivory"

Showing result 1 - 5 of 14 swedish dissertations containing the words leaf herbivory.

2. 1. Ecology and Evolution of Resistance to Herbivory : Trichome Production in Arabidopsis lyrata

   Author : Geir Løe; Jon Ågren; Kari Lehtilä; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Biology; Plant-animal interactions; herbivory; trichomes; plant resistance; plant defense; divergent selection; local adaptation; GLABROUS1; evolution; matrix population models; LTRE; Biologi; Biology; Biologi;

   Abstract : In this thesis, I examine variation in occurrence and performance of glabrous and trichome-producing plants of the perennial herb Arabidopsis lyrata. I combine field studies and genetic analysis to (1) examine the function of trichomes as a resistance character in natural populations, (2) compare the magnitude of population differentiation in trichome-production and at putatively neutral marker loci, (3) examine the molecular genetic basis of trichome-production, and (4) quantify the effects of herbivore removal on population growth and relative performance of glabrous and trichome-producing plants. READ MORE

4. 2. Biogeochemistry in Subarctic birch forests : Perspectives on insect herbivory

   Author : Jeppe Ågård Kristensen; MERGE: ModElling the Regional and Global Earth system; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Biogeochemistry; Aboveground-belowground interactions; Herbivory; Insects; Subarctic; Birch; soil microbes;

   Abstract : Herbivory can influence ecosystem processes, partly through long-term changes of the plant community compositions, but also more rapidly through the herbivores’ digestive alteration of the organic matter that is cycled through the soil and back to the primary producers. In the Subarctic mountain birch (Betula pubescens ssp. READ MORE

5. 3. Plant-Herbivore Interactions and Evolutionary Potential of Natural Arabidopsis lyrata Populations

   Author : Adriana Puentes; Jon Ågren; Jenny Hagenblad; Roosa Leimu Brown; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; plant defenses; leaf herbivory; floral herbivory; ontogeny; G-matrix; trade-offs; Biology with specialization in Ecological Botany; Biologi med inriktning mot ekologisk botanik; Biology with specialization in Evolutionary Genetics; Biologi med inriktning mot evolutionär genetik;

   Abstract : 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. READ MORE

6. 4. Ecology and evolution of tolerance in two cruciferous species

   Author : Elin Boalt; Kari Lehtilä; Johan Ehrlén; Julia Koricheva; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; herbivory; tolerance; methodology; Raphanus raphanistrum; Cardamine pratensis; folivory; apex removal; plant competition; ploidy levels; herbivore pressure; Other biology; Övrig biologi; växtekologi; Plant Ecology;

   Abstract : Tolerance to herbivory is the ability of plants to maintain fitness in spite of damage. The goal of this thesis is to investigate the genetic variation and expression of tolerance within species, determine whether and in what conditions tolerance has negative side-effects, and how tolerance is affected by different ecological factors. READ MORE

7. 5. Interactions between gray-sided voles (Clethrionomys rufocanus) and vegetation in the Fennoscandian tundra

   Author : Jonas Dahlgren; Lauri Oksanen; Johan Olofsson; John Terborgh; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; gray-sided voles; tundra vegetation; trophic cascades; plant-herbivore interactions; bilberry; plant communities; herbivory; plant resistance; Terrestrial ecology; Terrestisk ekologi;

   Abstract : I have, in this thesis, studied the interactions between gray-sided voles (Clethrionomys rufocanus) and tundra vegetation, on islands in, and mainland sites close to the lake Iešjávri, in northern Norway. As isolated islands are virtually free of predation, I have been able to compare plant-herbivore interactions in the presence and absence of predators. READ MORE