Fungal Fight Club: phylogeny and growth rate predict competitive outcomes among ectomycorrhizal fungi

Underground or above the surface opportunistic plant mutualists or Ectomycorrhizal fungi (EMF) associate themselves with almost all the trees on Earth. EMFs may extend access to resources, employ special enzymes for nutrients, and protect hosts against various root diseases making them a positive partner within natural forests. However, EMFs have been observed to alter their response toward environmental cues due to soil pH, competition, and various other factors. Focusing on pH, competition, and their effect, researchers have theorized that phylogenetic distance would be an effective predictor of competition and expect increased growth within lower pH levels. Amanita muscaria, Hebeloma cylindrosporum, Laccaria bicolor, Paxillus involutus, and Cenococcum geophilum were then plated using various controls, their results being inconsistent with known fungal responses to competition. The outcome of competition within single and pair controls was significantly altered based on which pH environment the fungi were placed in. Researchers also concluded phylogenetic and growth rate distance similarly predicted the effects of fungal competition, noting their interactions to be complex. Overall, their findings highlighted the need for further research to understand EMF’s response to competition and environmental changes. Future research may yield positive results that may potentially be used for environmental and agricultural use.  

The figure demonstrates the outline of the experiment: The different layouts used for testing control and competition (A), the Phylogeny of the five fungi used within the experiment (B), and examples of competitive growth from each fungal species (C). 

Legend: [A = A. muscaria, C = C. geophilum, H = H. cylindrosporum, L = L. bicolor, P = P. involutus]. 

Original Article: 

Alexander H Smith, Laura M Bogar, Holly V Moeller, Fungal Fight Club: phylogeny and growth rate predict competitive outcomes among ectomycorrhizal fungi, FEMS Microbiology Ecology, Volume 99, Issue 10, October 2023.