Occurrence of Phytophthora species in watercourses and reservoirs in Poland and the threat to cultivated plants by this genera.
Phytophthora species are very dangerous plant pathogens, which can multiplicate in water because of zoospore formation and spread within it in particular regions, country or even continent. Additionally, increase of international plant trade has also resulted in the introduction of new Phytophthora species and their spread. Seventeen Phytophthora species were detected in Polish rivers, canals and water ponds with domination of P. plurivora and furthermore P. cambivora, P. cinnamomi, P. citrophthora, P. megasperma and P. lacustris. Phytophthora spp. were detected from water over the year with restriction during summer and winter using the rhododendron leaf baits. It was shown that Phytophthora isolates, regardless of water source and detection period were pathogenic to the tested plant species.