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.
Cucurbita maxima Duchesne · Giant pumpkin
Lymar Anatolii Ostapovych, Kholodniak Liubov Volodymyrivna, Kholodniak Oleh Heorhiiovych,
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Instytut Ogrodnictwa - Państwowy Instytut Badawczy
Vitis L. · Grapevine
INSTITUT NATIONAL DE LA RECHERCHE AGRONOMIQUE, FR
Vitis vinifera L. · Common grape vine
Hochschule Geisenheim Institut fuer Rebenzuechtung
Cucumis melo L. · Melon
Laboratoire ASL S.N.C.
Triticum aestivum L. · Bread wheat
Sheredeko Leonid Mykolaiovych, Buriak Mykola Vasyl`ovych, Buriak Vasyl` IUkhymovych, Oksom Volodymyr Polikarpovych, Skryplov Volodymyr Oleksandrovych, Morhun Volodymyr Vasylovych,
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Cucumis sativus L. · Cucumber
Asgrow Seed Company (US)/Bruinsma (NL)
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
Information regarding the breeder received in the contribution to CPVO :Mouillère E.
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Cucumis sativus L. · Cucumber
Shevkunov Valerii Mykolaiovych, Prutens`ka Nataliia Oleksiivna, Shamshyna Anna Viacheslavovna, Portiankin Alieksiei IEvhenovych, Havrysh Serhii Fedorovych,
Citrullus lanatus (Thunb.) Matsum. & Nakai · Watermelon
HAZERA SEEDS BV
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Hordeum vulgare L. · Barley
Florimond Desprez Veuve et Fils, FR
Lactuca sativa L. · Lettuce
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Malus domestica (Suckow) Borkh. · Apple
DICKEY J.M. (US)
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Cucumis sativus L. · Cucumber
MERIDIEM SEEDS S.L.
Humulus lupulus L. · Common hop
Herbert Ehrmaier
Lolium perenne L. · Perennial ryegrass
DLF Seeds A/S
Vitis vinifera L. · Common grape vine
Hochschule Geisenheim University Institut für Pflanzenzüchtung Herrn Prof. Dr. Ernst Rühl
Solanum lycopersicum L. · Tomato
BHN SEED RESEARCH
Vitis L. · Grapevine
INSTITUT NATIONAL DE LA RECHERCHE AGRONOMIQUE, FR
Cucumis sativus L. · Cucumber
Andzhei Rostvorovskyi