XVI International Botanical Congess
Compatibility between the rhizosphere AM fungal communities associated with _Schizychrium scoparium_, _Andropogon gerardii_, and _Smilax rotundifolia_ with individuals of each plant species were examined in serpentine soils across a grassland/forest transition. Interestingly, plants had higher survival and biomass when grown with the AM fungi associated with the roots of other plant species. This suggests a negative feedback mechanism which would promote the coexistence of multiple plant/fungal combinations. The possibility of this pattern being caused by over-infection of host plants by their own rhizosphere AM fungal communities is discussed. Additionally, in most mycorrhizal combinations plants and fungi displayed increased compatibility when grown in the same soil the fungi were isolated from.