Potentilla sterilis, England, East Gloucestershire, VC33: aecia © Malcolm Storey, BioImages
Potentilla sterilis, Amstelveen, Thijsse-park: infected leaf.
uredinia and telia at the underside of the leaf
the uredinia are surrounded by sterile hyphae; they form a ring after the spores have been shed
no alternation of hostplant. Spermogonia epiphyllous, between epidermis and cuticula, often near the aecia. Aecia mostly hypophyllous, yellow, minute but larger on the veins, without a peridium but with a coronet of hyaline, sausage-shaped curved paraphyses; spores produced in chains, densely verrucose. Uredinia like the aecia, but spores single, pedicellate, strongly verrucose; the spores dry out quickly, and then look whitish. Telia hypophyllous black; spores long pedicellate, elliptic, dark brown, transversely divided into c. 4 almost smooth cells, the terminal one rounded, without an apiculus.
Rosaceae, narrowly oligophagous
Niet op Fragaria (Klenke & Scholler). The references to that host in Termorshuizen &Swertz probably concern P. sterilis, that has a treacherous similarity with F. vesca.
Phragmidium fragariastri (de Candolle) Schröter, 1887; Ph. granulatum Fuckel, 1869.
Bahcecioglu & Kabaktepe (2012a), Ellis & Ellis (1997a), Gäumann (1959a), González-Fragoso (1925a), Helfer (2005a), Henderson (2000a), Jage, Kruse, Kummer ao (2013a), Klenke & Scholler (2015a), Kozłowska, Mułenko & Heluta (2015a), Kruse (2014a), Maier, Begerow, Weiß & Oberwinkler (2003a), Mayor (1973a), Petrova & Denchev (2004a), Poelt & Zwetko (1997a), Riegler-Hagler (2002a,b), Ritz, Maier, Oberwinkler & Wissemann (2005a), Scheuer & Bechter (2012a), Termorshuizen & Swertz (2011a), Tóth (1994a), Vanderweyen & Fraiture (2007a), Wilson & Henderson (1966a), Woods, Stringer, Evans & Chater (2015a).