DRIVE

Biological introductions can theoretically reduce gene flow due to the limited number of founders and thus adaptability of invasive populations. However, multiple introduction events from different native source populations can result in admixed invasion fronts. Admixture can potentially favour introductions and invasion success, for example by increasing genetic variation and creating new genotypes on which selection and genetic drift can operate, or by eliminating deleterious recessive alleles due to inbreeding depression. Emerging fungal pathogens pose a growing threat to global health, ecosystems, food security, and the world economy. Whilst strictly clonal population structures should be observed in fungal populations, resulting in low fitness level and adaptation potential, recent studies found evidences of gene flow between previously known and newly identified genetic clusters, supporting the occurrence of (para)sexuality in fungal populations. Furthermore, since the diversity and sporulation of pathogenic fungi are strongly influenced by temperature, climate change is therefore likely to drive fungal replication via clonal or (para)sexual cycles with direct implications for strain diversity, transmission and virulence. However, our current understanding of the drivers of fungal pathogen strain diversity, selection and virulence remain a major gap of knowledge. Providing empirical support for these key questions remains novel and pioneer and have direct implications on food security (aquaculture, agriculture), biodiversity (terrestrial, aquatic), socio-economic and ecosystem services. DRIVE aims to characterize i) the role of clonal vs (para)sexual replicative mechanisms in driving fungal pathogen strains diversity among isolated hosts populations and ii) how thermal variations drive the selection and virulence of fungal pathogen strains at an individual and population level.