Large?scale study validates that regional fungicide applications are major determinants of resistance evolution in the wheat pathogen <i>Zymoseptoria tritici</i> in France

In modern cropping systems, the near-universal use of plant protection products selects for resistance in pest populations. The emergence and evolution this adaptive trait threaten treatment efficacy. We identified determinants fungicide quantified their effects at a large spatiotemporal scale. focused on Zymoseptoria tritici, which causes leaf blotch wheat. Phenotypes qualitative or quantitative to various fungicides were monitored annually, from 2004 2017, about 70 sites throughout 22 regions France (territorial units 25 000 km2 average). modelled changes frequency with regional anti-Septoria use, yield losses due disease area under organic major driver dynamics was estimated its effect increase relative apparent fitness each phenotype. predictions model replicated patterns observed field populations (R2 0.56 0.82). is mainly determined This study therefore showed that collective management scale could effectively complete local actions.