Poster
Florent Delplace
PostDoc
Laboratoire des Interactions Plantes-Microbes Environnement (LIPME), INRAE, CNRS, Université de Toulouse
Castanet-Tolosan, Occitanie, FRANCE
Mehdi Khafif
Engineer
Laboratoire des Interactions Plantes-Microbes Environnement (LIPME), INRAE, CNRS, Université de Toulouse
Castanet Tolosan, Midi-Pyrenees, France
Remco Stam
PI/Professor
Kiel University - Institute of Phytopathology
Kiel, Schleswig-Holstein, Germany
Adelin Barbacci
Researcher
Laboratoire des Interactions Plantes-Microbes Environnement (LIPME), INRAE, CNRS, Université de Toulouse
Castanet Tolosan, Midi-Pyrenees, France
Sylvain Raffaele
Senior Researcher
LIPME, INRAE - CNRS, Université de Toulouse, Castanet Tolosan, France
Castanet Tolosan, Midi-Pyrenees, France
Quantitative disease resistance (QDR) is the only form of plant immunity that mitigates disease symptoms caused by pathogens, including the necrotrophic fungus Sclerotinia sclerotiorum. Understanding the evolutionary origins of QDR is key to deciphering how resistance durability and spectrum evolve in plants. While interspecies comparisons of transcriptomic responses to S. sclerotiorum in Arabidopsis thaliana and five crop species have identified broadly conserved genes with regulatory divergence, the evolution of defense responses within a single species remains largely unexplored. To address this, we analyzed global gene expression in response to S. sclerotiorum across 23 A. thaliana accessions with contrasted QDR phenotypes. Over half of the species' pan-transcriptome exhibited local responses, while global reprogramming patterns were largely independent of accession phylogeny and geographical origin. Further analyses revealed that QDR phenotypes emerge from integrating multiple gene expression patterns, rather than a single regulatory pathway, with rewiring linked to variations in cis-regulatory elements. Finally, we constructed a transcriptome-phenotype map to explore evolutionary trajectories linking transcriptomic landscapes to QDR phenotypes. Our fitness landscape model reveals neutral regulatory networks linking diverse QDR-associated transcriptomes without compromising resistance, key features of robustness and evolutionary potential.