Diseases
Erysiphales
Powdery mildew is a fungal disease manifesting as a white web-like coating on plant organs, leading to tissue necrosis, fruit deformation, and significant crop losses.
Mentioned in descriptions 33 570 varieties reference book.
Powdery mildew is caused by ectoparasitic fungi of the order Erysiphales, which develop primarily on the surface of leaves, shoots, and fruits. The initial white web-like coating eventually densifies into "powdery" cushions, upon which fungal fruiting bodies may form as dark spots. As a result of the infection, tissues turn yellow and become necrotic, fruits may crack, and leaves drop prematurely.
The intensity of disease development depends on a complex of factors: high relative humidity, moderate temperatures, the presence of dense canopy, and excessive nitrogen nutrition. Risks increase with alternating dry and wet weather. The harmfulness of the disease is expressed in a reduction of the leaf assimilation area, deterioration of crop quality, and a decrease in the general winter hardiness of crops.
Assessment of variety resistance is conducted under field conditions at various stages of vegetation, most often during the full heading phase. To classify the degree of infection, scoring systems or intensity scales in percentages are used, where varieties with up to 10% infection are considered highly resistant (R), 11 to 40% as moderately resistant (M), and more than 41% as susceptible (S). Variety resistance is ensured by genetic mechanisms that prevent colonization by the pathogen or limit the development of its mycelium.
Selection based on the description text, not official resistance ratings: such data is not available in registers. Mention indicates that the trait is discussed in the variety's sources; see the variety's profile for details on what is specifically stated.
x Triticosecale Wittm. ex A. Camus · Triticale
DR RALF SCHACHSCHNEIDER
Triticum aestivum L. · Bread wheat
W WEIBULL
Rosa L. · Rose
Wilhelm Kordes / Tim-Hermann Kordes / Margarita Kordes in Fa. W. Kordes' Söhne Rosenschulen GmbH & Co KG
Triticum aestivum L. · Bread wheat
Limagrain Europe S.A.S
Hordeum vulgare L. · Barley
KWS MOMONT RECHERCHE SARL, FR
Rosa L. · Rose
W. Kordes Sohne Rosenschulen GmbH & Co KG| DE
Avena sativa L. · Oat
NORDSAAT Saatzuchtgesellschaft mbH - Zuchtstation Granskevitz - Dr. Steffen Beuch
Capsicum annuum L. · Bell pepper
INSTITUT NATIONAL DE LA RECHERCHE AGRONOMIQUE, FR
Triticum aestivum L. · Bread wheat
KWS Momont, F
Malus domestica (Suckow) Borkh. · Apple
THE KENT INCORPORATED SOCIETY
Triticum aestivum L. · Bread wheat
Danko Hodowla Roslin Sp. Zo.o., Pl- 64-000 Koscian
Triticum aestivum L. · Bread wheat
Malopolska Hodowla Roslin Spolka z o.o.
Avena sativa L. · Oat
Nordsaat Saatzuchtgesellschaft mbH
Cucumis sativus L. · Cucumber
Zoldesegtermesztesi Kutato Intezet RT (HU)
Lolium multiflorum Lam. · Italian ryegrass
Prof. Dr. ir. Dirk Reheul c/o Universität Gent - Afd. Planten- teelt en Plantenveredeling
Lolium multiflorum Lam. ssp. italicum (A. Br.) Volkart · Italian ryegrass
Feldsaaten Freudenberger GmbH&Co.KG
Cucumis sativus L. · Cucumber
NUNHEMS
Triticum aestivum L. · Bread wheat
Saaten Union Recherche (FR)
Triticum aestivum L. · Bread wheat
Saaten Union Recherche SARL, Estrées-Saint -Denis FR
Brassica rapa L. subsp. campestris (L.) A. R. Clapham · Field mustard
Boreal Plant Breeding Ltd, FIN-31600 Jokioinen
Avena sativa L. · Oat
Saatzucht Edelhof
Cucumis melo L. · Melon
RIJK ZWAAN Z.Z. B.V.
Cucumis sativus L. · Cucumber
MORAVOSEED
Triticum durum Desf. · Durum wheat
Farmers Marketing Corporation