Gymnosporangium sabinae (Dickson) Winter, 1884
on Pyrus
Pyrus pyraster, Belgium, prov. Namur, Couvin (Frasnes), Carrière des Grosses Haies: spermogonia © Stéphane Claerebout
detail
the underside of the leaf is clearly galled here
Pyrus communis, Elburg © Arnold Grosscurt
underside of leaf with aecia
Pyrus calleryana, Hongarije, Budapest © László Érsek
fresh galling
horizontal section, with initials of aecia
vertical section
aecium initial
fresh aecia
gall
in spring epiphyllous pustular spermogonia. Later large orange coloured hypophyllous gallings develop, with up to 2 cm high aecia, opening by a number of lateral slits.
spermogonia, aecia
Rosaceae, monophagous
Pyrus betulifolia, calleryana, communis & subsp. pyraster, elaeagrifolia, nivalis, orientalis, pashia, pyrifolia, regelii, salicifolia, spinosa, syriaca.
on Juniperus
gall
only telia, on swellings of the branches, ± conical, up to 2 mm high, yellowish brown when moist. Teliospores in two forms: hyaline, thin-walled, stout, and brown, thick-walled, slender; spores apically conical. They measure 20-30 x 38-40 µm; each of the two cells with 2 germination pores close to the separation wall.
telia
Cupressaceae, narrowly monophagous
Juniperus chinensis, excelsa, oxycedrus, phoenicea, sabina, thurifera, virginiana.
synonyms
Gymnosporangium fuscum de Candolle, 1905; Roestelia cancellata Rebentisch, 1804.
parasite
notes
On pear very common, striking, and damaging.
Closely related with G. sabinae is Gymnosporangium atlanticum, described from Morocco, and possibly occurring also in Spain. The teliospores of G. sabinae are only slightly constricted at the septum and have only two germ pores per cell near the septum, while the teliospores of G. atlanticum are clearly constricted at septum and have up to 6 germ pores per cell with different arrangement (Fernández, Llorens & Alvarado).
references
Bahcecioglu & Kabaktepe (2012a), Bahçecioğlu, Kabaktepe & Yildiz (2006a), Bellmann (2012a), Blumer (1946a), Brandenburger (1985a: 29), Buhr (1964b), Chinery (2011a), Dauphin & Aniotsbehere (1997a), Deckert & Deckert (2016a), Dervis, Dixon, Doğanlar & Rossman (2010a), Fernández, Llorens & Alvarado (2016a), Gäumann (1959a), Gjærum, Gauslaa & Talgø (2008a), González-Fragoso (1925a), Groom (2011a), Helfer (2005a), Henderson (2000a, 2004a), Jage, Klenke, Kruse oo (2016a), Jage, Kruse, Kummer ao (2013a), Jage, Scholler & Klenke (2010a), Karlsson (2008a), Klenke & Scholler (2015a), Kozłowska, Mułenko & Heluta (2015a), Kruse (2014a, 2019a), Llorens i Villagrasa (1984a), Maier, Begerow, Weiß & Oberwinkler (2003a), Maier, Wingfield, Mennicken & Wingfield (2007a), Negrean (1996b, 1997a), Poelt & Zwetko (1997a), Preece & Hick (1994a), Redfern & Shirley (2011a), Riegler-Hager (2000a), Roskam (2009a), Scheuer & Bechter (2012a), Termorshuizen & Swertz (2012a), Unamuno (1941b), Vanderweyen & Fraiture (2008a), Wilson & Henderson (1966a), Woods, Stringer, Evans & Chater (2015a), Zhao, Liu, Li & Cai (2016a).