A new species of Pustula (Oomycetes, Albuginales) is the causal agent of sunflower white rust

摘要: White blister rust of sunflower is an emerging disease that among the most important diseases in this crop South Africa and has recently spread to Europe. For genus Albugo, it been demonstrated species are mostly at least host specific several previously overlooked present on Brassicaceae. It thus seems likely unrecognised also Pustula. Based previous phylogenetic reconstruction combination with differences oospore ornamentation, revealed Pustula sunflower, attributed tragopogonis (syn. Albugo tragopogonis), distinct from Tragopogon. Therefore, pathogen described as a new species, helianthicola. In addition, taxonomic observations incorrect name replaced by combination, obtusata.