Final Activity Report Summary - FRAGEVOL (Evolution in fragmented plant populations: plant genetic variation, mating system, fitness, and natural enemies)
The objective of this project was to examine the evolution of plant-herbivore interactions and of plant mating system in fragmented landscape. More specifically, we aimed to examine the effects of inbreeding and among-population outbreeding on herbivore resistance, tolerance and plant fitness in relation to the history of inbreeding, herbivory and the abiotic environment. This project was among the first to examine the effects of inbreeding and inter-population outbreeding on herbivore resistance and tolerance in a multi-population setting.
Understanding the effects of inbreeding on direct plant fitness and their interactions with other organisms and how these effects vary among plant populations with different abiotic, biotic and genetic conditions is essential considering the general increase in levels of inbreeding following decreased size of plant populations. Effects of inter-population crosses are, in turn, central in the conservation context, if we want to transplant plants between populations for restoration purposes.
We found both inbreeding and outbreeding depression in resistance and tolerance against herbivore damage. Whether the effects of inbreeding and outbreeding were negative or positive varied, however, between populations of origin depending on their genetic, biotic and abiotic history. These studies highlight how inbreeding and outbreeding effects on herbivore resistance and plant fitness are influenced by the history of inbreeding, levels of herbivory, and environmental conditions at the site of plant origin. This clearly demonstrates that generalisations on inbreeding and outbreeding effects from single-population studies, which so far has been the norm, can be very misleading. The results suggest that complex interactions between the genetic and environmental conditions directly affecting resistance, tolerance and fitness play a role for inbreeding and outbreeding depression and that allocation costs for resistance or growth and fitness also need to be considered.
Thus, as proposed, the project combined some of the fundamental questions and aspects currently of wide interest for ecologists, evolutionary and conservation biologists. The results of the project provide novel information on the evolutionary changes taking place in fragmented populations combining ecological and evolutionary approaches in a conservation context, and integrating multidisciplinary methods and skills. Furthermore, the results further increase our understanding of the mating systems of plants, and especially highlight the role of biological interactions in plant mating system evolution. Since maintaining sustainable levels of biodiversity requires maintaining the diversity of habitats, species, the level of genetic variation, as well as the key processes that influence the function of ecosystems, the results of the study have important implications for conservation of biodiversity.
Understanding the effects of inbreeding on direct plant fitness and their interactions with other organisms and how these effects vary among plant populations with different abiotic, biotic and genetic conditions is essential considering the general increase in levels of inbreeding following decreased size of plant populations. Effects of inter-population crosses are, in turn, central in the conservation context, if we want to transplant plants between populations for restoration purposes.
We found both inbreeding and outbreeding depression in resistance and tolerance against herbivore damage. Whether the effects of inbreeding and outbreeding were negative or positive varied, however, between populations of origin depending on their genetic, biotic and abiotic history. These studies highlight how inbreeding and outbreeding effects on herbivore resistance and plant fitness are influenced by the history of inbreeding, levels of herbivory, and environmental conditions at the site of plant origin. This clearly demonstrates that generalisations on inbreeding and outbreeding effects from single-population studies, which so far has been the norm, can be very misleading. The results suggest that complex interactions between the genetic and environmental conditions directly affecting resistance, tolerance and fitness play a role for inbreeding and outbreeding depression and that allocation costs for resistance or growth and fitness also need to be considered.
Thus, as proposed, the project combined some of the fundamental questions and aspects currently of wide interest for ecologists, evolutionary and conservation biologists. The results of the project provide novel information on the evolutionary changes taking place in fragmented populations combining ecological and evolutionary approaches in a conservation context, and integrating multidisciplinary methods and skills. Furthermore, the results further increase our understanding of the mating systems of plants, and especially highlight the role of biological interactions in plant mating system evolution. Since maintaining sustainable levels of biodiversity requires maintaining the diversity of habitats, species, the level of genetic variation, as well as the key processes that influence the function of ecosystems, the results of the study have important implications for conservation of biodiversity.