Cyanus segetum, Loenen (Ge.), 18.vi.2013 © Arnold Grosscurt

also the stems are affected

leaf with telia

stem with uredinoid aecia (brown) and telia (black)

gall

No host plant alternation. Spermogonia honey coloured. The first formed uredinia on leaves and stems, later ones only (amphigenous) on the leaves, pulverulent, dark cinnamon brown. Urediniospores spinulose with 2 equatorial germination pores that are not surrounded by a smooth zone. Telia on all parts of the plant, black, pulverulent. Teliospores 2-celled, on a short, fragile pedicel.

host plants

Asteraceae, narrowly oligophagous

centaurea cheirolopha, ensiformis, glastifolia, iberica, lycopifolia, phrygia subsp. salicifolia, polypodiifolia, urvillei, virgata; Cyanus pichleri, segetum, triumfettii & subsp. axillaris.

Also on cultivated cornflowers.

references

Bahçecioğlu & Kabaktepe (2012a), Bahçecioğlu, Kabaktepe & Yildiz (2006a), Brandenburger (1985a: 660), Buhr (1964b), Dauphin & Aniotsbehere (1997a), Ellis & Ellis (1997a), Gäumann (1959a), Gjaerum (1986a), González Fragoso (1924a), Hafellner (1980a), Henderson (2000a, 2004a), Klenke & Scholler (2015a), Kozłowska, Mułenko & Heluta (2015a), Kruse (2014a, 2019a), Poelt & Zwetko (1997a), Redfern & Shirley (2011a), Riegler-Hager (2007a), Roskam (2009a), Termorshuizen & Swertz (2011a), Tomasi (2014a), Unamuno (1941b), Vanderweyen & Fraiture (2011a), Wilson & Henderson (1966a).