Peronospora violacea Berk. is an obligate floricolous Peronospora. All floricolous parasitic fungi of the family Peronosporaceae belong to the genus Peronospora Corda, probably to only one evolutional complex; of the foliicolous parasitic species, Peronospora destructor (Berk.) Casp. is their closest relative. It is impossible to distinguish individual microspecies within P. violacea Berk. on the basis of host plants; three new host species were found. The systemic infection of the Knautia species by both indirect and direct methods (replanting, histological proof of mycelium) was demonstrated. The data on oospores were corrected and completed. Basing on the revision of all materials preserved in the Czechoslovak public herbarium collections, a map of distribution of this species in Czechoslovakia was compiled and evaluated. A special chapter is devoted to the problems of nomenclature.
Horáková J., Skalický V. (1989): Contribution to the ecology of Peronospora violacea Berk. – Česká Mykologie 43(1): 13–29.
