Intraspecific Variation in Mycorrhizal Growth Responses of Paper Birch (Betula papyrifera) to Arbuscular and Ectomycorrhizal Fungi

One of the most ecologically important and widespread symbioses occurs between mycorrhizal fungi and plants. Populations of plant species that associate with mycorrhizal fungi can be uniquely adapted to certain species of fungi, while still maintaining the ability to associate with multiple species of fungi. Arbuscular mycorrhizal fungi and ectomycorrhizal fungi are adapted to different temperature and soil nutrient conditions. I predicted that plant populations from different temperature and soil nutrient conditions would respond differently to being colonized by arbuscular and ectomycorrhizal fungi. To test my hypotheses, I conducted a common garden experiment with eight populations of Betula papyrifera and measured their mycorrhizal growth responses. The results indicated that while the populations respond differently to arbuscular and ectomycorrhizal fungi, there is no relationship between the temperature and soil nutrient conditions of the host populations and their mycorrhizal growth responses.