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.
Triticum aestivum L. · Bread wheat
Gesellschaft für goetheanistische Forschung e.V.
Pisum sativum L. · Pea
Syngenta Seeds B.V.
Triticum aestivum L. · Bread wheat
Mesterhazy Akos / Matuz Janos / Kertesz Zoltan / Barabas Zoltan / Mozsik Lajosne / Beke Bela / Csoesz Laszlone / Falusi Janos / Nagy Istvan / Szabo Csilla
Lactuca sativa L. · Lettuce
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
x Triticosecale Wittm. ex A. Camus · Triticale
Hodowla Roslin Strzelce Sp z.o.o. Grupa IHAR
Vitis L. · Grapevine
R.Gilg et Succ. SA (FR)
Cucumis sativus L. · Cucumber
Semo, CZ
Solanum lycopersicum L. · Tomato
Enza Zaden Beheer B.V.
x Triticosecale Wittm. ex A. Camus · Triticale
Institut National de Recherche pour l'Agriculture l'Alimentation et l'Environnement (INRAE)
Triticum durum Desf. · Durum wheat
Groupement Agricole Essonnois (FR)
Avena sativa L. · Oat
Berthold Alter
Cucurbita pepo L. · Field pumpkin
FRANK FRANCIS
Hordeum vulgare L. · Barley
Landwirtschaftliche Fachschule Edelhof Saatzucht
Solanum lycopersicum L. · Tomato
Kees Konst
Cucumis melo L. · Melon
PETOSEED CO
Cucurbita pepo L. · Field pumpkin
MORAVOSEED
Helianthus annuus L. · Sunflower
RAGT 2N S.A.S
Hordeum vulgare L. · Barley
DE COSTER DANIEL| Daniel de Coster c/o N.V. Clovis Matton S.A.
Beta vulgaris Sugar Beet Group · Sugar beet
SAS FLORIMOND-DESPREZ Veuve et Fils
Cucumis sativus L. · Cucumber
MORAVOSEED
Triticum aestivum L. · Bread wheat
Institut national de recherche pour l'agriculture, l'aliment (FR)/Agri Obtentions SA (FR)
Hordeum vulgare L. · Barley
Nordic Seed A/S
Cucumis sativus L. · Cucumber
ENZA ZADEN
Cucurbita pepo L. · Field pumpkin
Syngenta Crop Protection AG