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.
Beta vulgaris Sugar Beet Group · Sugar beet
KWS SAAT SE and CO KGAA
Triticum aestivum L. · Bread wheat
LOCHOW-PETKUS
Triticum aestivum L. · Bread wheat
ETS.C.C.BENOIST
Triticum aestivum L. · Bread wheat
SELGEN A.S
Cucumis sativus L. · Cucumber
Sakata Seed Corporation
Hordeum vulgare L. · Barley
SAATZUCHT JOSEF BREUN GmbH&Co.KG
x Triticosecale Wittm. ex A. Camus · Triticale
Agri-Obtentions S.A., Institut National de Recherche pour l'Agriculture l'Alimentation et l'Environnement (INRAE)
Fragaria L. · Strawberry
INSTITUTE OF HORTICULTURAL
Solanum lycopersicum L. · Tomato
SEMILLAS FITO, S.A.
Linum usitatissimum L. · Common flax
Laboulet Semences, FR
Hordeum vulgare L. · Barley
W. von Borries-Eckendorf GmbH & Co.KG
Triticum aestivum L. · Bread wheat
Roothaan, M.E.
Hordeum vulgare L. · Barley
Virágmag Kft., Szentgál
x Triticosecale Wittm. ex A. Camus · Triticale
Institut national de recherche pour l'agriculture, l'aliment (FR)/Agri Obtentions SA (FR)
Secale cereale L. · Rye
PHP PETERSEN
Hordeum vulgare L. · Barley
CEZEA SLECHTITELSKA STANICE A.S.
Beta vulgaris Sugar Beet Group · Sugar beet
Van der Have Sugarbeet (NL)
Hordeum vulgare L. · Barley
BUSCH AGRICULTURAL RESOUR
Malus Mill. · Apple
PURDUE RESEARCH FOUNDATION
Beta vulgaris Sugar Beet Group · Sugar beet
KWS Saat AG, DE
Trifolium pratense L. · Red clover
SAATZUCHT| Saatzucht Steinach GmbH & Co KG
Cucumis sativus L. · Cucumber
SEMINIS VEGETABLE SEEDS, NL
Cucumis sativus L. · Cucumber
SATIMEX QUEDLINBURG HANDELSGESELLSCHAFT GmbH
Cucumis sativus L. · Cucumber
HILD SAMEN GMBH