The present invention relates to a for obtaining a plant showing a reduced susceptibility towards infection with a pathogen, in particular an oomycete, comprising treating MO seeds of a plant species to be modified with a mutagenic agent to obtain M1 seeds and growing plants therefrom the thus obtained M1 seeds to obtain M1 plants, inoculation of the thus obtained M1+n plants with the pathogen and selecting plants that show a reduction or absence of sporulation of the pathogen as plants having a reduced susceptibility phenotype. The invention further relates to plants, seeds, pollen, cells and tissues that have the reduced susceptibility towards oomycetes.