Association between virulence and triazole tolerance in the phytopathogenic fungus Mycosphaerella graminicola

PLoS One. 2013;8(3):e59568. doi: 10.1371/journal.pone.0059568. Epub 2013 Mar 15.

Abstract

Host resistance and synthetic antimicrobials such as fungicides are two of the main approaches used to control plant diseases in conventional agriculture. Although pathogens often evolve to overcome host resistance and antimicrobials, the majority of reports have involved qualitative host - pathogen interactions or antimicrobials targeting a single pathogen protein or metabolic pathway. Studies that consider jointly the evolution of virulence, defined as the degree of damage caused to a host by parasite infection, and antimicrobial resistance are rare. Here we compared virulence and fungicide tolerance in the fungal pathogen Mycosphaerella graminicola sampled from wheat fields across three continents and found a positive correlation between virulence and tolerance to a triazole fungicide. We also found that quantitative host resistance selected for higher pathogen virulence. The possible mechanisms responsible for these observations and their consequences for sustainable disease management are discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ascomycota / drug effects*
  • Ascomycota / pathogenicity*
  • Drug Resistance, Fungal*
  • Fungicides, Industrial / pharmacology*
  • Plant Leaves / microbiology
  • Plants / microbiology*
  • Triazoles / pharmacology*

Substances

  • Fungicides, Industrial
  • Triazoles
  • cyproconazole

Grants and funding

The project was supported by Chinese National Science Foundation Grant no. 31071655 and Swiss Federal Institute of Technology Grant TH-49a/02-1. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.