Plants and fungi--growing together
Massicotte, Hugues .
Challenging the (botany) rules: mycoheterotrophy and mixotrophy as plant strategies.
Most plants worldwide use chlorophyll to convert the sun's energy for growth and reproduction. There exist, however, plants that have gained independence (partial or full) from the sun by obtaining carbohydrates indirectly from other photosynthetic plants via fungal bridges. A question that arises is whether plants that exhibit this apparent "carbon budget deficit" may also be approaching an evolutionary dead-end. This presentation will explore aspects of the biology of these plants, their global distribution, what is known about their general life cycles and the fungi involved, key morphological features, and cellular root features that permit the transfer of critical metabolites from the donor to the receiver plant. Two groups of plant-fungal interactions will be discussed. Monotropoid plants, which are involved in mycoheterotrophic interactions, develop associations with a very restricted number of ectomycorrhizal fungal species (some forming hypogeous sporocarps) and obtain their carbon exclusively from neighbor plants via these fungi. In contrast, pyroloid plants are involved in mixotrophic interactions and develop symbiotic associations with a broad spectrum of fungal associates. Current evidence suggests that pyroloid plants exist mid-way on the trophic continuum; they are able to use some carbohydrate from their own photosynthesis in combination with imported carbon and nitrogen from adjacent donor plants. The biological and evolutionary consequences of these tripartite arrangements will be discussed.
Log in to add this item to your schedule
1 - University of Northern British Columbia, Ecosystem Science and Management Program, 3333 University Way, Prince George, B.C., V2N 4Z9, Canada
Presentation Type: Symposium or Colloquium Presentation
Date: Wednesday, July 30th, 2008
Time: 4:45 PM