Chemical communication between the endophytic fungus Paraconiothyrium variabile and the phytopathogen Fusarium oxysporum

PLoS One. 2012;7(10):e47313. doi: 10.1371/journal.pone.0047313. Epub 2012 Oct 15.

Abstract

Paraconiothyrium variabile, one of the specific endophytic fungi isolated from the host plant Cephalotaxus harringtonia, possesses the faculty to inhibit the growth of common phytopathogens, thus suggesting a role in its host protection. A strong antagonism between the endophyte P. variabile and Fusarium oxysporum was observed and studied using optic and electronic microscopies. A disorganization of the mycelium of F. oxysporum was thus noticed. Interestingly, the biological effect of the main secondary metabolites isolated from P. variabile against F. oxysporum did not account for this strong antagonism. However, a metabolomic approach of pure fungal strains and confrontation zones using the data analysis tool XCMS were analyzed and pointed out a competition-induced metabolite production by the endophyte in the presence of the phytopathogen. Subsequent MS/MS fragmentations permitted to identify one of the induced metabolites as 13-oxo-9,11-octadecadienoic acid and highlighted a negative modulation of the biosynthesis of beauvericin, one of the most potent mycotoxin of F. oxysporum, during the competition with the endophyte.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibiosis*
  • Ascomycota / chemistry
  • Ascomycota / metabolism*
  • Cephalotaxus / microbiology
  • Endophytes / metabolism
  • Fusarium / chemistry
  • Fusarium / drug effects
  • Fusarium / growth & development*
  • Linolenic Acids / chemistry
  • Linolenic Acids / toxicity
  • Mycelium / drug effects*
  • Mycelium / growth & development
  • Plant Diseases / microbiology

Substances

  • Linolenic Acids
  • 13-oxo-9,11-octadecadienoic acid

Grants and funding

The French Ambassy at Dakar, Senegal and Cheikh Anta Diop University at Dakar are acknowledged providing a research fellowship to IN. This project was supported by the following grants: « Projets Innovants FRB 2009 » from the Fondation pour la Recherche sur la Biodiversité (AAP-IN-2009-026), the Action Transversale du Muséum « Biodiversité des microorganismes dans les écosystèmes actuels et passés » from the Muséum National d’Histoire Naturelle, by the “Consortium National de Recherche en Génomique”, and the “service de systématique moléculaire” of the Muséum National d’Histoire Naturelle (IFR 101). It is part of the agreement n° 2005/67 between the Genoscope and the Muséum National d’Histoire Naturelle on the project “Macrophylogeny of life” directed by Guillaume Lecointre. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript can be added to the manuscript.