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Investigation of Plant Interactions Across Common Mycorrhizal Networks Using Rotated Cores
Published on: March 26, 2019
Dark septate endophytes: mutualism from by-products?
Anna L Ruotsalainen1, Miia Kauppinen2, Piippa R Wäli3
1Department of Ecology and Genetics, POB 3000, University of Oulu, FI-90014 Oulu, Finland.
Abstract:
Plant roots are abundantly colonized by dark septate endophytic (DSE) fungi in virtually all ecosystems. DSE fungi are functionally heterogeneous and their relationships with plants range from antagonistic to mutualistic. Here, we consider the role of by-product benefits in DSE and other root-fungal symbioses. We compared host investments against symbiont-derived benefits for the host plant and categorized these benefits as by-products or benefits requiring reciprocal investment from the host. By-product benefits may provide the variability required for the evolution of invested mutualisms between the host and symbiont. We suggest that DSE could be considered as 'a by-product mutualist transitional phase' in the evolution of cooperative mycorrhizal symbionts from saprotrophic fungi.
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