Original Research ARTICLE
Responses to hydric stress in the seed-borne necrotrophic fungus Alternaria brassicicola
- 1INRA Institut de Recherche en Horticulture et Semences, France
- 2Institute of Integrative Biology and Systems, Faculty of Science and Engineering, Laval University, Canada
- 3EA7394 Institut Charles Viollette, France
- 4Department of Agronomy, University of Córdoba, Spain
- 5University of Agronomic Sciences and Veterinary Medicine, Romania
- 6UMR7267 Ecologie et biologie des interactions (EBI), France
The necrotrophic fungus Alternaria brassicicola causes black spot disease and is an economically important seed-borne pathogen of Brassicaceae species. Its transmission to seed is a major component of pathogen fitness, as this fungus strongly depends on this process for its dispersal and long-term survival. Recent studies, conducted with the Arabidopsis thaliana / A. brassicicola pathosystem, showed that the level of susceptibility of the fungus to water stress strongly influenced its seed transmission ability.
In this study, we gained further insights into the mechanisms involved in the seed infection process by analysing the transcriptomic and metabolomic responses of germinated spores of A. brassicicola exposed to water stress. Then, the repertoire of putative hydrophilins, a group of proteins that are assumed to be involved in cellular dehydration tolerance, was established in A. brassicicola based on the expression data and additional structural and biochemical criteria. Phenotyping of single deletion mutants deficient for fungal hydrophilin-like proteins showed that they were affected in their transmission to A. thaliana seeds, although their aggressiveness on host vegetative tissues remained intact.
Keywords: Hydrophilins, Plant pathogenic fungus, Seed transmission, Dehydration, Alternaria brassicicola
Received: 18 Sep 2018;
Accepted: 09 Aug 2019.
Copyright: © 2019 N'Guyen, Raulo, Brisach, Iacomi, Pelletier, Renou, Bataillé-Simoneau, Campion, Bastide, Hamon, Mouchès, Porcheron, Lemoine, Kwasiborski, Simoneau and Guillemette. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Thomas Guillemette, INRA Institut de Recherche en Horticulture et Semences, Beaucouzé, France, firstname.lastname@example.org