The Evolution of Mutualism in Grass-Endophyte Associations

  • Heather H. Wilkinson
  • Christopher L. Schardl


Mutualisms are interspecific interactions between individuals in which each participant receives a net benefit from the association (Thompson, 1994). The concept of mutualism is broad encompassing a wide variety of non-antagonistic and non-commensal interspecific interactions. Generally, these interactions involve and exchange of goods or services (e.g. nutrition, protection, dispersal of gametes or progeny). By definition the goods or services provided by a partner should be of low cost relative to the benefits it receives from the association. Therefore, to demonstrate that an association is mutualistic it is necessary to show a relative increase in the fitness of each partner.


Tall Fescue Perennial Ryegrass Fungal Endophyte Fungal Symbiont Asexual Species 
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Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  • Heather H. Wilkinson
    • 1
  • Christopher L. Schardl
    • 1
  1. 1.Department of Plant PathologyUniversity of KentuckyLexingtonUSA

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