Dr Jari Valkonen is the professor of plant pathology at University of Helsinki, Finland. His areas of expertise are in molecular virus-plant interactions and pathogen defence of plants. Most of his research and published works concern viruses of potato and sweetpotato and aim especially to deeper understanding of the antiviral mechanisms. Since early 1990s his studies have included collaboration with CIP and since middle 1990s East African institutes, such as Makerere University, Uganda, and Mikocheni Agricultural Research Institute, Tanzania. An important aspect of the studies is also education of young scientists. Among those over 30 doctoral theses completed or on-going out under his supervision, eight are focused on viruses in sweetpotato or cassava in East Africa and five are authored by East African scientists. Valkonen is currently involved in the Seed Potato Development Project in Tanzania supported by the Finnish government and coordinated by CIP.