Populations of Phytophthora infestans in northern and eastern Europe

Abstract Phytophthora infestans (Mont.) de Bary is an oomycete plant pathogen that causes late blight in potato ( Solanum tuberosum L.) and tomato ( Solanum lycopersicum L.). This review documents the population structure of P. infestans in northern and eastern Europe, and aims to explain the differences between populations of P. infestans in this region and in western Europe. Populations of P. infestans are influenced by many factors, e.g., migrations related to the movement of potato seed tubers, possibility of sexual reproduction, changes in climate, and agricultural management practices. All the presented factors may have a significant impact on the P. infestans population structure. The knowledge on P. infestans populations varies strongly depending on country and time, even within the rather intensively studied region of eastern and northern Europe. Our review indicates some knowledge gaps, such as a lack of data for some countries and gaps in some years in population monitoring. This indicates the need to continue the monitoring of P. infestans populations.