Phytophthora pseudosyringae is a semi-papillate homothallic soil-borne plant pathogen causing root and collar rot of broadleaf tree species in Europe.

[1] It is associated with necrotic fine roots and stem necroses of Fagus sylvatica and Alnus glutinosa, and isolates are moderately aggressive to fine roots of oaks and beech (Nothofagus[2]), highly aggressive to holly leaves and apple fruits, and slightly pathogenic to alder bark.

It belongs to the class of oomycetes and is often described as a ‘fungal-like’ organism since they form a heterotrophic mycelium as the ‘true fungi’, but in contrast, their cell wall lacks chitin and is composed only of cellulose and glucans.

[citation needed] Its name derives from Greek Phytophthora φυτόν (phytón), “plant” and φθορά (phthorá), “destruction”; “the plant-destroyer” and plurivora and from Latin (pluri = many, -vora = feeding).

This heterokont-related article is a stub.