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.
Prunus persica (L.) Batsch · Peach
Arsene Maillard Laurence Maillard
Cucumis sativus L. · Cucumber
CAPITAL GENETIC EBT, S.L.
Cucumis sativus L. · Cucumber
SUNSEEDS
Triticum aestivum L. · Bread wheat
Balla Laszlo / Bedoe Zoltan / Lang Laszlo / Szunics Laszlo / Szunics Laszlone / Karsai Ildiko
Solanum lycopersicum L. · Tomato
PLANTENKWEKERIJ VREUGDENHIL B.V.
Nicotiana tabacum L. · Tobacco
Boris A. Stoyanov, Boris K. Chinchev, Hristo N. Georgiev, Dimitar S. Shabanov, Stanimir Ts. Ralovski
Malus domestica (Suckow) Borkh. · Apple
Domaine Public (FR)
Hordeum vulgare L. · Barley
SEMILLAS BATLLE, S.A.
Cucurbita pepo L. · Field pumpkin
Enza Zaden Beheer B.V.
Triticum aestivum L. · Bread wheat
Rybalka Oleksandr Illich, Babaiants Lazar Tihranovych, Reshetnikova Valentyna Semenivna, Solomonov Ruslan V'iacheslavovych, Maksymov Mykola Havrylovych, Holub IEvheniia Anatoliivna, Rubakha Serhii Andriiovych, Lytvynenko Raisa Ivannivna, Honcharuk Nina Ol
Lactuca sativa L. · Lettuce
Vilmorin-Mikado SAS (FR)
Malus domestica (Suckow) Borkh. · Apple
Dactylis glomerata L. · Cocksfoot
DEUTSCHE SAAT| Deutsche Saatveredelung AG
Capsicum annuum L. · Bell pepper
ALEJANDRO MARTIN CARA
Capsicum annuum L. · Bell pepper
SEMILLAS FITO, S.A.
Daucus carota L. · Carrot
Vilmorin & Cie
Cucurbita pepo L. · Field pumpkin
Syngenta Crop Protection AG
Cucurbita pepo L. · Field pumpkin
INTERSEMILLAS SAU
Cucurbita pepo L. · Field pumpkin
ZETA SEEDS S.L.
Capsicum annuum L. · Bell pepper
Enza Zaden Beheer B.V.
Cucumis melo L. · Melon
SEMILLAS FITO, S.A.
Hordeum vulgare L. · Barley
SEMILLAS BATLLE, S.A.
Cucumis sativus L. · Cucumber
SEMILLAS FITO, S.A.
Malus domestica (Suckow) Borkh. · Apple
VÝZKUMNÝ A ŠLECHTITELSKÝ ÚSTAV OVOCNÁŘSKÝ HOLOVOUSY s.r.o. (CZ)