Quantitative pathogenicity and host adaptation in a fungal plant pathogen revealed by whole-genome sequencing

Archive ouverte

Amezrou, Reda | Ducasse, Aurélie | Compain, Jérôme | Lapalu, Nicolas | Pitarch, Anais | Dupont, Laetitia | Confais, Johann | Goyeau, Henriette | Kema, Gert, H. J. | Croll, Daniel | Amselem, Joëlle | Sanchez-Vallet, Andrea | Marcel, Thierry, C

Edité par CCSD ; Nature Publishing Group -

International audience. Knowledge of genetic determinism and evolutionary dynamics mediating host-pathogen interactions is essential to manage fungal plant diseases. Studies on the genetic architecture of fungal pathogenicity often focus on large-effect effector genes triggering strong, qualitative resistance. It is not clear how this translates to predominately quantitative interactions. Here, we use the Zymoseptoria tritici-wheat model to elucidate the genetic architecture of quantitative pathogenicity and mechanisms mediating host adaptation. With a multi-host genome-wide association study, we identify 19 high-confidence candidate genes associated with quantitative pathogenicity. Analysis of genetic diversity reveals that sequence polymorphism is the main evolutionary process mediating differences in quantitative pathogenicity, a process that is likely facilitated by genetic recombination and transposable element dynamics. Finally, we use functional approaches to confirm the role of an effector-like gene and a methyltransferase in phenotypic variation. This study highlights the complex genetic architecture of quantitative pathogenicity, extensive diversifying selection and plausible mechanisms facilitating pathogen adaptation.

• Description
• Sujet/Public
• Outil
• Outil d'anticipation
• Mémoire et thèse
• Gestion