Gula
Protection expiredHordeum vulgare L. · Barley
Vive, Kurt
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.
Hordeum vulgare L. · Barley
Vive, Kurt
Triticum aestivum L. · Bread wheat
Landwirtschaftliche Fachschule Edelhof Saatzucht
Triticum aestivum L. · Bread wheat
FLORIMOND DESPREZ VEUVE ET FILS
Malus Mill. · Apple
Reinhard Kaneppele - Termeno (IT)
Cucumis sativus L. · Cucumber
Harris Moran Seed (US)
Triticum aestivum L. · Bread wheat
BAYERISCHE PFLANZENZUCHTGESELLSCHAFT EG & CO
Cucumis melo L. · Melon
SEMINIS INC
Hordeum vulgare L. · Barley
MÅ IKKE BENYTTES - BENYT SW DE
Rosa L. · Rose
Pepinieres et Roseraies Georges Delbard| FR
Hordeum vulgare L. · Barley
Carlsberg Research (DK)
Beta vulgaris Sugar Beet Group · Sugar beet
Societe Europeenne de Semences NV/SA (BE)
Cucumis melo L. · Melon
PETOSEED CO
Triticum aestivum L. · Bread wheat
EMMERT GEORG
Beta vulgaris Sugar Beet Group · Sugar beet
Margaret Rekoske
Beta vulgaris Sugar Beet Group · Sugar beet
Margaret Rekoske
Beta vulgaris Sugar Beet Group · Sugar beet
Margaret Rekoske
Cucumis sativus L. · Cucumber
Rijk Zwaan Zaadteelt en Zaadhandel BV (NL)
Begonia L. · Begonia
M. KOPPE B.V
Rosa L. · Rose
ODENDAHL| Franz Josef Odendahl (Rosenhof Odendahl)
Beta vulgaris Sugar Beet Group · Sugar beet
Henning Friehe
Hordeum vulgare L. · Barley
ZELDER
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Avena sativa L. · Oat
Selgen a.s., CZ
Solanum lycopersicum L. · Tomato
Vreugdenhil Breeding & Seeds B.V.