OomycetesPhytophthoraSaprolegniaPythiumAlgal ProteinsAphanomycesDNA, AlgalPhytophthora infestansFungiPetroselinumPlant DiseasesPeronosporaPlantsPlant ImmunityPhylogenyGenomeGene Transfer, HorizontalHost-Parasite InteractionsHost-Pathogen InteractionsMolecular Sequence DataCelluloseAmino Acid SequencePlant LeavesVirulence