Erysiphe syringae-japonicae (Braun) Braun & Takamatsu, 2000

on Ligustrum, Syringa

Erysiphe syringae-japonicae: cleistothecium on Syringa vulgaris

Syringa vulgaris, Belgiuum, prov. Antwerp, Meerhout © Carina Van Steenwinkel

Erysiphe syringae-japonicae: cleistothecium on Syringa vulgaris

another specimen

Erysiphe syringae-japonicae: cleistothecium on Syringa vulgaris

appendages

Erysiphe syringae-japonicae: cleistothecium on Syringa vulgaris

asci

Erysiphe syringae-japonicae: cleistothecium on Syringa vulgaris

ascus

gall

Amphigenous mildew bloom on the leaves. Conidia solitary, elliptic, without fibrosin bodies. Cleistothecia with 3-10 asci, containing (5-) 8 spores. Appendages 4-16, equatorial, about as long as the diameter; they are stiff, brown over at least the basal part, with maximally 1, basal septum. At their end they are several times dichotomously branched in a flat plane.

hostplants

Oleaceae, oligophagous

Ligustrum vulgare; Syringa x chinensis, josikaea, komarowii, x persica, x prestoniae, tomentella & subsp. sweginzowii + yunnanensis, villosa & subsp. wolfii, vulgaris.

Perhaps German material from Acer opalus is also attributable to this species (Braun ao, 2009a).

synonyms

Microsphaera aceris Bunkina, 1974.

notes

when this Asiatic species for appeared in Europe in 1990 the differences with E. syringae, on almost the same host spectre, seemed clear: syringae: asci with 3-6 spores and appendages hyaline or brownish only at the very base; syringae-japonicae: asci with 5-8 spores and appendages partly brown. However, later research has demonstrate a much larger variability of syringae, to the point that the two would have been synonymised if molecular data had not shown convincing differences. The only practical, albeit not definite, difference is that syringae (in Europe) forms cleistothecia anly very rarely, while syringae-japonicae froms them profusely.

references

Akata & Heluta (2015a), Bacigálová & Marková (2006a), Beenken & Senn-Irlet (2016a), Braun, Ale-Agha, Bolay ao (2009a), Braun & Cook (2012a), Braun, Cunnington, Brielmaier-Liebetanz ao (2003a), Jage, Klenke, Kruse ao (2016a), Jage, Kruse, Kummer ao (2013a), Klenke & Scholler (2014a), Kruse & Jage (2014a), Mułenko, Piątek, Wołczańska ao (2010a), Piątek (2003b, 2005b), Scheuer & Bechter (2012a), Takamatsu, Shiroya & Seko (2016a), Talgø, Sundheim, Gjærum ao (2010a).

04/03/2017

pub 27.v.2017 · mod 12.viii.2017