Helianthus laetiflorus, Belgium, prov. Antwerp, Meerhout © Carina Van Steenwinkel

infected leaves, upperside

infected lef, underside, with cleistothecia

cleisothecia also on the stem!

cleistothecium with appendages

two asci with spores

the unusually long foot cell of the conidiophore

conidium

gall

mycelium amphigenous, thin, white, almost persistent. Appressoria nipple-shaped, single or paired. Conidia formed in chains, without fibrosin bodies. Foot-cell of conidiophore generally straight, unusually long (35-80 µm), followed by 1-3 shorter cells. Cleistothecia not rare, amphigenous, with 5-15 asci, containing 2(-3) spores. Appendages numerous, sub-equatorial, 0.5-2 x the diameter; they are mycelioid, mostly simple, septate, ultimately entirely brown.

host plants

Asteraceae, narrowly oligophagous:

Ambrosia artemisiifolia, confertiflora, psilostachya, trifida; Helianthus annuus, atrorubens, debilis, decapetalus, doronicoides, laetiflorus, maximilianii, pauciforus, petiolaris, salicifolius, scaberrimus, strumosus, tuberosus; Heliopsis helianthoides; Iva frutescens, xanthifolia; Pappobolus microphyllus; Rudbeckia fulgida, hirta, laciniata, laevigata, nitida; Zinnia angustifolia, elegans, haageana.

synonyms

Erysiphe cichoracearum var. latispora Braun, 1983; Golovinomyces cichoracearum var. latispora (Braun) Braun, 1999.

references

Beenken & Senn-Irlet (2016a), Braun & Cook (2012a), Bresinsky (2016a), Jage, Kruse, Kummer ao (2013a), Jage, Klenke & Kummer (2010a), Klenke & Scholler (2015a), Kruse (2014a, 2019a), Kruse & Jage (2014a), Leysen (2017a), Mieslerová, Kitner, Petřeková, ao (2020a), Negrean & Anastasiu (2006a), Piątek (2004a), Ruszkiewicz-Michalska (2006a)m Ruszkiewicz-Michalska & Michalski (2005a), Świderska, Wołczańska, Kozłowska ao (2005a).