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Visar resultat 1 - 5 av 6 avhandlingar som matchar ovanstående sökkriterier.
1. Reproductive Biology and Population Genetics of Common Ash (Fraxinus excelsior L.)
Sammanfattning : Common Ash, Fraxinus excelsior L. (Oleaceae) is a wind-pollinated, wind-dispersed, deciduous tree, commonly occurring throughout Central and Northern Europe. The thesis addresses several questions concerning reproductive biology and factors influencing the genetic richness of ash stands. LÄS MER
2. Sexual conflict and selection on pistil and pollen traits
Sammanfattning : The incidence of sexual selection in plants is today acknowledged, however, just as in animals, evolution and maintenance of mate choice is gravely underexplored. Moreover, the potential for sexual conflicts to occur in plants has only been assessed empirically to a very limited degree. LÄS MER
3. Nutrient supply to reed canary grass as a bioenergy crop : intercropping and fertilization with ash or sewage sludge
Sammanfattning : Production of renewable energy from herbaceous crops on agricultural land is of great interest since fossil fuels need to be replaced with sustainable energy sources. Reed canary grass (RCG), Phalaris arundinacea L. is an interesting species for this purpose. LÄS MER
4. Ecological genetics of inbreeding, outbreeding and immunocompetence in Ranid frogs
Sammanfattning : Using artificial fertilization, I crossed frogs from different populations to evaluate fitness consequences for the offspring from an inbreeding-outbreeding perspective, and to evaluate quantitative genetic effects on immunocompetence against a fungal pathogen (Saprolegnia). Crosses between closely situated populations of different sizes generated contrasting results for the effects of outbreeding on offspring traits between populations and life history stages, emphasizing the importance of epistatic effects and the difficulties of relying on generalizations when making conservation decisions (e. LÄS MER
5. Regulatory Control of Autumn Senescence in Populus tremula
Sammanfattning : Autumn senescence is a visually spectacular phenomenon in which trees prepare for the oncoming winter. The mechanism for regulation of autumn senescence in trees has been very hard to pinpoint. In this thesis the main focus is to investigate how autumn senescence is regulated in aspens (Populus tremula). LÄS MER