Epicoccum layuense a potential biological control agent of esca-associated fungi in grapevine

PLoS One. 2019 Mar 26;14(3):e0213273. doi: 10.1371/journal.pone.0213273. eCollection 2019.

Abstract

Epicoccum is a genus of ascomycetes often associated with the mycobiome of grapevines (Vitis vinifera). Epicoccum spp. are found in the soil, phyllosphere, as well as in the wood, where they interact both with the plant and with other endophytes and pathogens. Wood pathogens involved in the esca disease complex, a grapevine trunk disease, are particularly concerning in viticulture, as current control strategies have proven unsatisfactory. This study investigated the interaction among Epicoccum spp. and three esca-associated fungi, with the aim of establishing whether they are suitable candidates for biological control.A screening conducted in vitro, by means of dual culture, revealed that all tested Epicoccum spp. inhibited the growth of pathogens Phaeomoniella chlamydospora and Fomitiporia mediterranea, while only some of them inhibited Phaeoacremonium minimum. Epicoccum layuense E24, identified as the most efficient antagonist, was tested in rooted grapevine cuttings of cultivars Cabernet Sauvignon and Touriga Nacional, under greenhouse conditions, against P. chlamydospora and P. minimum. This study revealed that the inoculation of E. layuense E24 produced a successful colonization of the wood of grapevines; in addition it did not impair the growth of the plants or induce the appearance of symptoms in leaves or in wood. Moreover, grapevines colonized by E. layuense E24 showed a considerable decrease in the wood symptomatology caused by the inoculated pathogens (by 31-82%, depending on the pathogen/grapevine cultivar), as well as a reduction in their frequency of re-isolation (60-74%).Our findings suggest that E. layuense E24 is a promising candidate for its application in biological control, due to its antagonistic interaction with some esca-associated fungal pathogens.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ascomycota / physiology*
  • Biological Control Agents*
  • Plant Diseases / microbiology
  • Plant Diseases / prevention & control*
  • Vitis / drug effects*
  • Vitis / microbiology
  • Wood / drug effects
  • Wood / microbiology

Substances

  • Biological Control Agents

Grants and funding

This study was funded by the Horizon 2020 Programme of the European Commission within the Marie Skłodowska-Curie Innovative Training Network “MicroWine” (grant number 643063 to G. Del Frari) and by Portuguese national funds through Fundação para a Ciência e a Tecnologia, grant SFRH/BPD/84508/2012 for Ana Cabral and FCT Unit funding UID/AGR/04129/2013 (LEAF). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.