Recent Changes in the Pathogenic Variability of Plasmopara Halstedii (Sunflower Downy Mildew) Populations from Different Continents

Abstract

AbstractThe obligate biotrophic Oomycete, Plasmopara halstedii, causal agent of sunflower downy mildew, is capable of producing new pathogenic races over time. Although changes in the P. halstedii race composition were reviewed for the first time in 2007, since then the pathogen has continued to change its virulence character dramatically. There was a need, therefore, to update information on pathogenic diversity of P. halstedii by making accounts of the temporal and spacial changes in the pathogen populations in North and South America and Europe. This paper, based on current publications and personal communications, attempts to present an accurate overview of races in Europe and Americas for the last 7 years.