First report on the occurrence of Phytophthora obscura on Acer pseudoplatanus in Slovakia

Abstract Sycamore maple is a valuable admixture species in many European countries, including Slovakia. As most species belonging to the genus Acer , it is susceptible to several pathogenic organisms including species of Oomycetes. To determine whether the decline of Acer pseudoplatanus in Slovakia is caused by pathogenic Oomycetes, soil samples were taken from the rhizosphere in three sycamore maple stands. Isolation from leaf baits and subsequent identification based on sequencing of the ITS showed the presence of three species: Pythium intermedium , Phytophthora plurivora and Phytophthora obscura . This is the first report on the occurrence of P . plurivora and P . obscura in the rhizosphere of declining sycamore maple stands in Slovakia.