Ecological Consequences of Inbreeding in Plants for Plant-Herbivore Interactions
David E Carr
Blandy Experimental Farm
More than half of all plant species self-pollinate at least 20% of the time and almost all species studied suffer reduced fitness as a result of inbreeding. Despite decades of intensive, detailed studies of the propensity and fitness consequences of inbreeding in plants, virtually nothing is known about how inbreeding influences the biology of organisms that regularly interact with inbred plants. It is likely that the loss of genetic variation within inbreeding individuals and the associated phenotypic changes in inbred plants will greatly affect other interacting populations of plants and animals. We are expanding the study of inbreeding in plants to include the interaction of plant mating-system and insect herbivory. We will conduct a series of greenhouse and field experiments to test the hypotheses that inbreeding in plants exacerbates the negative effects of herbivory and alters the quality of the host for insect herbivores. We will also partition genetic variation for herbivore resistance and host plant quality into its additive and non-additive components to assess the ability of inbreeding populations to respond to selection imposed by herbivores. Our collaborative study will be the first to unite the important disciplines of plant mating-system evolution and plant-herbivore interactions. The results of this study will have important implications for plant mating-system evolution, for the evolution of resistance in host populations, and for the long-term persistence of population fragments experiencing rising levels of inbreeding. Our results will also be relevant to the development of agricultural crops via selective breeding programs. From the herbivore's perspective, this study will provide insight into the ability of insects to respond to the environmental heterogeneity created by a mixed-mating host and their ability to exploit hosts that have restricted gene flow. As natural landscapes become increasingly fragmented, understanding the genetic and ecological processes that transpire within small populations is critical to conservation management.
More information at www.virginia.edu
Project Sponsored By: U.S. Nsf - Directorate For Biological Sciences
Start Date: 8/15/2000
- End Date: 7/31/2005
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