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.
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Instytut Ogrodnictwa - Państwowy Instytut Badawczy
Ribes nigrum L. · Blackcurrant
Kopan` Kira Mykolaivna, Kopan Volodymyr Pavlovych,
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Cucurbita pepo L. · Field pumpkin
Domaine Public (FR)
Daucus carota L. · Carrot
Daniel Gabillard
Brassica oleracea L. (White Cabbage Group) · White cabbage
L. DÆHNFELDT A/S
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Cucumis melo L. · Melon
HM Clause SAS (FR)
Malus domestica (Suckow) Borkh. · Apple
NOLENS VINCENT
Malus domestica (Suckow) Borkh. · Apple
Gospodarstwo Szkółkarskie Andrzej i Szymon Nowakowscy
Ribes uva-crispa L. · Gooseberry
Sherenhovyi Vitalii Petrovych, Hontar Vasyl` Terentiiovych, Sherenhovyi Petro Zakharovych,
Beta vulgaris Sugar Beet Group · Sugar beet
KWS Saat AG, DE
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Fragaria L. · Strawberry
DE PAUW F.M.S.
Cucumis melo L. · Melon
Dr. V.S.S. Rao
Prunus persica (L.) Batsch · Peach
Latsko Tetiana Anatoliivna, Smykov Volodymyr Karpovych, Perfil`ieva Zoia Mykolaivna, Oriekhova Valentyna Petrivna,
Allium fistulosum L. · Welsh onion
Shinji iioka
Cucumis sativus L. · Cucumber
Krylov Oleh Mykolaiovych, Borysov Oleksandr Volodymyrovych,
Vitis vinifera L. · Common grape vine
Dr. Bernd H.E. Hill c/o Staatl. Lehr-u.VA für Wein und Obstbau, Ref. Rebenzüchtung
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Ribes nigrum L. · Blackcurrant
Lietuvos agrarinių ir miškų mokslų centro filialas Sodininkystės ir daržininkystės institutas
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Cucumis sativus L. · Cucumber
Prutenskaia Nataliia Oleksiivna, Shamshyna Anna Viacheslavovna, Portiankin Alieksiei IEvhenovych, Havrysh Serhii Fedorovych,