Plants collaborate with many micro-organisms in the rhizosphere to form mutualistic associations. One of the best examples is the mycorrhizal symbio- sis between plants and fungi. Here, fungi support plants with mineral nutri- ents and other services and the fungi, in turn, receive photosynthates from the autotrophic plants. Mycorrhizal associations are common in almost all eco- systems and 80 % of all land plants associate with these mutualistic soil fungi. There is an increasing awareness among biologists, ecologists and mycolo- gists that mycorrhizal associations need to be considered in...