Visar resultat 1 - 5 av 67 avhandlingar innehållade ordet Pollination.
Sammanfattning : Ephedra (Gnetales) is a gymnosperm genus with a long evolutionary history; the first dispersed pollen grains with affinity to the group are known already from the Permian. This thesis focuses on the evolutionary history of the group and different aspects of its pollination mechanisms. LÄS MER
Sammanfattning : Pollination is one of the most important factors determining the reproductive success of plants. This thesis examines processes associated to varying pollination, with focus on plant responses. The first aim was to examine the possibility and constraints for short-term evolution of flower size in Raphanus raphanistrum. LÄS MER
Sammanfattning : Agricultural intensification and associated loss of semi-natural grasslands, has resulted in reduced landscape heterogeneity. A concomitant loss of forage and nest sites for pollinating insects has driven declines across several pollinator taxa. LÄS MER
4. The impact of forest on pest damage, pollinators and pollination services in an Ethiopian agricultural landscape
Sammanfattning : The distribution of wild biodiversity in agroecosystems affect crop performance and yield in various ways. In this thesis I have studied the impact of wild biodiversity, in terms of trees and forest structures, on crop pests, pollinators and the pollination services provided in a heterogeneous landscape in southwestern Ethiopia. LÄS MER
Sammanfattning : Pollination, i.e., the transport of male gametophytes to female gametophytes, can occur with biotic or abiotic vectors and is necessary for fertilization and completion of the lifecycle in all seed plants. LÄS MER