Blumeria graminis (de Candolle) Speer, 1975

on Poaceae

Blumeria graminis on Holcus mollis

Holcus mollis, Beunigen (ov): the lowest, oldest, leaves are infected and start yellowing

Blumeria graminis on Holcus mollis

Holcus mollis, Denekamp; lg. Singraven: advanced infection

Blumeria graminis on Elytrigia repens

Elytrigia repens, Nieuwendam: upperside of a leaf

Blumeria graminis

detail, enlarged

Blumeria graminis conidia

the conidia are formed in a string

Blumeria graminis: cleistothecia

cleistothecium

Blumeria graminis: cleistothecium squeezed

opened cleistothecium, with still unripe asci

Blumeria graminis: base of conidia string

Blumeria graminis: ripe conidia

Holcus mollis, Denekamp; lg. Singraven: characteristic for Blumeria is a swelling at the base of the conidia chain; at right three mature conidia

gall

mycelium amphigenous, also on the stems and in the inflorescence, effuse, persistent, ultimately a greyish brown felt. Appressoria nipple-shaped, single or paired. Conidia formed in chains, elliptic, without fibrosin bodies. Foot cell of conidiophore with a bulbous swelling. Cleistothecia depressed, with 6-30 asci, generally containing 8 spores. Appendages in varying number, sub-equatorial, mostly shorter than the diameter; they are mycelioid, simple, septate.

hostplants

Poaceae, broadly oligophagous

Achnatherum calamagrostis; Aegilops crassa, cylindrica, tauschii, ventricosa; Aegilotrichum triticoides; Agropyron cristatum; Agrostis alpina, canina, capillaris, castellana, gigantea, stolonifera; Aira caryophyllea, elegantissima; Alopecurus aequalis, geniculatus, myosuroides, pratensis, rendlei; Ammochloa; Andropogon; Anisantha madritensis, rigida, sterilis, tectorum; Anthoxanthum aristatum, odoratum, ovatum; Apera interrupta, spica-venti; Aristavena setacea; Arrhenatherum elatius; Avena barbata, brevis, fatua, nuda, sativa & subsp. chinensis, sterilis, strigosa; Avenella flexuosa; Avenula pubescens; Beckmannia; Bellardiochloa variegata; Boissiera, Bouteloua; Brachypodium pinnatum, sylvaticum; Briza maxima, media, minor; Bromopsis benekenii, erecta, inermis, ramosa; Bromus arvensis, commutatus, grossus, hordeaceus, japonicus, lanceolatus, racemosus, secalinus, squarrosus; Calamagrostis arundinacea, canescens, epigeios, rivalis, villosa; Catabrosa aquatica; Catapodium rigidum; Ceratochloa carinata, cathartica; Cinna; Cleistogenes; Coleanthus subtilis; Cornucopiae; Corynephorus canescens; Crithopsis; Cutandia; Cynodon dactylon; Cynosurus cristatus, echinatus; Dactylis glomerata & subsp. lobata; Danthonia alpina, decumbens; Dasypyrum; Deschampsia cespitosa; Digitaria sanguinalis; Dinebra; Drymochloa sylvatica; Echinaria; Elymus caninus; Elytrigia intermedia, juncea & subsp. boreoatlantica, repens; Eragrostis cilianensis, tef; Eremopoa; Eremopyrum; Festuca alpina, heterophylla, ovina, rubra, stricta subsp. trachyphylla; Gastridium; Gaudinia fragilis; Glyceria maxima; Helictochloa bromoides, planiculmis, pratensis; Helictotrichon desertorum; Hierochloe australis, odorata; Holcus lanatus, mollis; Hordelymus europaeus; Hordeum marinum, murinum, vulgare & subsp. spontaneum; Koeleria glauca, macrantha, pyramidata; Lagurus ovatus; Lamarckia aurea; Leersia; Leymus arenarius; Lolium multiflorum, perenne, remotum, temulentum; Macrochloa tenacissima; Melica ciliata, nutans, persica, trassilvanica, uniflora; Mibora minima; Micropyrum tenellum; Milium effusum; Molinia caerulea; Muhlenbergia; Nardus stricta; Ochlopoa annua; Oplismenus; Panicum virgatum; Parapholis; Pennisetum villosum; Phalaris; Phleum alpinum, hirsutum, paniculatum, phleoides, pratense; Phragmites australis; Phyllostachys; Pilgerochloa; Piptatherum paradoxum; Poa alpina, angutifolia, bulbosa, cenisia, chaixii, compressa, glauca, minor, molinerii, nemoralis, palustris, pratensis, pumila, remota, trivialis, versicolor; Polypogon monspeliensis; Psathyrostachys juncea; Psilurus incurvus; Puccinellia distans & subsp. limosa, maritima; Rostraria cristata; Saccharum; Schedonorus arundinaceus, giganteus, pratensis; Schismus; Sclerochloa dura; Secale cereale, strictum, vavilovii; Sesleria autumnalis, caerulea, heufleriana, latifolia, rigida; Setaria adhaerens, italica; Sphenopus; Sporobolus; Stipa barbata; Taeniatherium; Tripidium; Trisetum distichophyllum, flavescens, spicatum; Triticale, Triticosecale blaringhemii; Triticum aestivum & subsp. spelta; Vulpia bromoides, geniculata, myuros, unilateralis.

synonyms

Erysiphe graminis de Candolle, 1815; Oidium monilioides (Nees) Link, 1924 (anamorph).

notes

In Europe, the only powdery mildew on grasses. Within the species there is a, perhaps even large, number of races, “formae speciales”, specialised on a particular genus or species of host plant.

Blumer (1946a) remarks that this species is found almost exclusively in the neighbourhood of houses, mostly close to a wall.

references

Blumer (1946a, 1967a), Brandenburger (1985a), Braun (1995a), Braun & Cook (2012a), Bresinsky (2016a), Czerniawska (2001a), Czerniawska, Madej, Adamska ao (2000a), Doppelbaur & Doppelbaur (1973a), Dynowska, Fiedorowicz & Kubiak (1999a), Ellis & Ellis (1997a), Heluta, Hayova, Tykhonenko ao (2010a), Jage, Klenke, Kruse ao (2016a), Jage, Klenke & Kummer (2010a), Jage, Kruse, Kummer ao (2013a), Jage, Scholler & Klenke (2010a), Klenke & Scholler (2015a), Kozłowska, Mułenko & Heluta (2015a), Kruse (2014a), Kruse & Jage (2014a), Kruse, Thiel, Brodtbeck ao (2017a), Kummer (2012a), Mayor (1971a), Melgarejo Nárdiz, García-Jiménez, Jordá Gutiérrez ao (2010a), Mułenko, Sałata & Wołczańska (1995a), Negrean (1996b), Özaslan, Hüseyin & Erdogdu (2014a), Negrean & Denchev (2004a), Oberhaensli, Parlange, Buchmann ao, (2011a), Ruszkiewicz-Michalska (2006a), Scheuer & Bechter (2012a), Scholler, Reinhard & Schubert (1996a), Speer (1973a), Unamuno (1941a, 1942a, 1943a).

mod 28.iii.2019