ARS | Publication request: First report of Erysiphe knautiae (Erysiphales) on Lomelosia caucasica (Caucasian pincushion flower) in North America

Submitted to: Plant Health Progress
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 7, 2012
Publication Date: March 1, 2012
Citation: Dugan, F.M. 2012. First report of Erysiphe knautiae (Erysiphales) on Lomelosia caucasica (Caucasian pincushion flower) in North America. Plant Health Progress. Online doi:10.1094/PHP-2012-0227-01-BR.

Interpretive Summary: A species of powdery mildew, Erysiphe knautiae, is reported on Caucasian pincushion flower, Lomelosia (Scabiosa) caucasica, for the first time in North America. Caucasian pincushion flower is native to west Asia, but propagated in gardens in North America and elsewhere. This same powdery mildew has been previously reported on other species of pincushion flower from Washington State, and on L. caucasica from Europe and western Asia. A report of 'Oidium sp.' from New York State is very probably the same species. Horticultural publications often refer to 'powdery mildew' on various species of pincushion flower, without providing either genus or species assignment for the fungus. The USDA-ARS Western Regional Plant Introduction Station is the unit of the National Plant Germplasm System in which Scabiosa species are propagated and stored.

Technical Abstract: A powdery mildew, Erysiphe knautiae, is reported on Lomelosia caucasica (synonym Scabiosa caucasica, Caucasian pincushion flower) for the first time in North America. Lomelosia is now recognized as a genus distinct from, albeit closely related to, Scabiosa. The host range of E. knautiae seemingly extends to the family Dipsacaceae sensu lato. The significance of other reports of E. knautiae, on species of pincushion flower still assigned to Scabiosa or on Knautia arvensis (another member of that family), are discussed.