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.
Avena sativa L. · Oat
Lantmannen ek for, SE 268-81 Svalov
Cucumis melo L. · Melon
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Hordeum vulgare L. · Barley
Graminor AS, N-2322 Ridabu
Avena sativa L. · Oat
Wiersum Plantbreeding B.V.
Hordeum vulgare L. · Barley
Graminor AS, N-2322 Ridabu
Beta vulgaris Sugar Beet Group · Sugar beet
Societe Europeenne de Semences NV/SA (BE)
Triticum aestivum L. · Bread wheat
Wiersum Plantbreeding B.V.
Triticum durum Desf. · Durum wheat
SEMILLAS BATLLE, S.A.
Triticum aestivum L. · Bread wheat
Saatzucht Donau GmbH, Probstdorf AT
Triticum aestivum L. · Bread wheat
STRUBE GMBH&CO.KG
Cucumis sativus L. · Cucumber
MORAVOSEED
Avena sativa L. · Oat
SARL ADRIEN MOMONT ET FILS, FR
x Triticosecale Wittm. ex A. Camus · Triticale
Danko Hodowla Roslin Sp.z.o.o.
Solanum lycopersicum L. · Tomato
Kees Konst
x Triticosecale Wittm. ex A. Camus · Triticale
NORDSAAT Saatzuchtgesellschaft mit beschränkter Haftung Herrn Dr. Ralf Schachschneider
Beta vulgaris Sugar Beet Group · Sugar beet
KWS SAAT SE and CO KGAA
Ribes nigrum L. · Blackcurrant
Stichting Tuin. Proef. (NL)/G Hanet (FR)
Lolium multiflorum Lam. ssp. italicum (A. Br.) Volkart · Italian ryegrass
Joordens Zaadhandel (NL)
x Triticosecale Wittm. ex A. Camus · Triticale
LANTMÄNNEN SEED
Hordeum vulgare L. · Barley
Nordic Seed A/S
Triticum aestivum L. · Bread wheat
Asur Plant Breeding, F
Hordeum vulgare L. · Barley
Nordsaat Saatzucht GmbH Saatzucht Langenstein
Triticum aestivum L. · Bread wheat
STRUBE D and S GMBH
Beta vulgaris Sugar Beet Group · Sugar beet
KWS, D