Evolution of eudicots quantitative disease resistance to necrotrophic fungal pathogens

• Applicant: Professor Dr. Remco Stam
• Subject Area: Plant Breeding and Plant Pathology
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 490719370

ResiDevo aims to understand the mechanisms underlying the diversity and evolution of disease resistance to necrotrophic fungal pathogens in plants. Our key hypothesis, derived from our preliminary data and evolutionary theories is thatmany QDR genes evolved early in Angiosperm evolution and acquired diversified modes of regulation to create diversified QDR responses in modern plant populations. The immediateobjective of this proposal is to compare global responses to necrotrophic fungi in plants from two botanical families to infer general rules underlying the diversification of these responsesat various evolutionary scales (intra and inter specific). We address four main objectives using comparative analyses in plant species from the Brassicales (Arabidopsis thaliana and others)and Solanales (Solanum chilense and others) and two Ascomycete pathogens with similar lifestyle (necrotrophic, foliar, asexual) and contrasted host range (generalist and specialist) as tractable organisms for this approach.We will: 1) Characterize intra and inter specific variation in the plant QDR phenotypes and identify major resistance Quantitative Trait Loci (QTLs). 2) Document the diversity of transcriptional reprogramming during QDR at different levels: species, family, order. 3) Study the evolution of sequence and expression for genes responsive to fungal pathogens at the population, genus and family levels, and 4) Validate key components of QDR in Brassicales and Solanales and study the genome scale impact of transcription factors recruitment into QDR.This interdisciplinary work will generate unprecedented datasets for evolutionary studies of plant‐microbe interactions including: 1) Phenotypic diversity on a comparable scale for plants covering the population, genus and family levels inoculated by fungi from two distinct Classes of the Ascomycetes. 2) A so far unique transcriptomics dataset allowing to test a number of key theoretical predictions and to mine for genes contributing to the QDR phenotype across species 3) Complete evolutionary analyses of pathogen‐responsive genes in several plant lineages, and 4) In depth functional characterization of the role of a few transcription factors in QDR and the genome-scale consequences of their natural sequence/regulatory diversificationResiDEvo will lead to conceptual advances on the evolution of the plant immune system. It will it will identify and validate the role of novel resistance mechanisms conserved across two botanical families and offer promising applied perspectives thanks to data generated on included cultivated species.

• DFG Programme: Research Grants
• International Connection: France
• Cooperation Partner: Dr. Sylvain Raffaele