Soil fungal pathogens and the relationship between plant diversity and productivity

Ecol Lett. 2011 Jan;14(1):36-41. doi: 10.1111/j.1461-0248.2010.01547.x. Epub 2010 Nov 14.


One robust result from many small-scale experiments has been that plant community productivity often increases with increasing plant diversity. Most frequently, resource-based or competitive interactions are thought to drive this positive diversity-productivity relationship. Here, we ask whether suppression of plant productivity by soil fungal pathogens might also drive a positive diversity-productivity relationship. We created plant assemblages that varied in diversity and crossed this with a ± soil fungicide treatment. In control (non-fungicide treated) assemblages there was a strong positive relationship between plant diversity and above-ground plant biomass. However, in fungicide-treated assemblages this relationship disappeared. This occurred because fungicide increased plant production by an average of 141% at the lower ends of diversity but boosted production by an average of only 33% at the higher ends of diversity, essentially flattening the diversity-productivity curve. These results suggest that soil pathogens might be a heretofore unappreciated driver of diversity-productivity relationships.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Biodiversity*
  • Biomass
  • Fungi / physiology*
  • Host-Pathogen Interactions
  • Plant Physiological Phenomena*
  • Soil Microbiology*