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.
Secale cereale L. · Rye
PRZEDSIęBIORSTWO NASIENNE "ROLNAS" SP. Z O.O.
Solanum lycopersicum L. · Tomato
Axia Vegetable Seeds B.V.
Triticum aestivum L. · Bread wheat
Sejet Planteforaedling I,S
Triticum aestivum L. · Bread wheat
W. von Borries-Eckendorf GmbH & Co.KG
Prunus persica (L.) Batsch · Peach
PERFIL'EVA ZOYa NIKOLAEVNA / SMYKOV ANATOLIJ VLADIMIROVICh / SMYKOV VLADIMIR KARPOVICh / FEDOROVA OL'GA STEPANOVNA / LATSKO TAT'YaNA ANATOL'EVNA / LOBANOVSKAYa VALENTINA FEDOROVNA
Ribes uva-crispa L. · Gooseberry
Humulus lupulus L. · Common hop
Slovenian Institute of Hop Research and Brewing
Capsicum annuum L. · Bell pepper
Syngenta Crop Protection AG
Cucumis melo L. · Melon
Clause (FR)
Chrysanthemum L. · Chrysanthemum
Fides B.V.
Cucumis melo L. · Melon
SEMILLAS FITO, S.A.
Beta vulgaris Sugar Beet Group · Sugar beet
STRUBE D and S GMBH
Vitis vinifera L. · Common grape vine
Dr. Norbert Becker im Staatl. Weinbauinstitut
Cucumis sativus L. · Cucumber
Kamil Bartkowski Gospodarstwo Hodowlano-Nasienne Bartkowscy
Triticum aestivum L. · Bread wheat
NICKERSON (UK)
Cucumis melo L. · Melon
Clause Semences SA (FR)
Cucurbita pepo L. · Field pumpkin
SAKATA SEED AMERICA INC US
Cucumis sativus L. · Cucumber
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Cucumis melo L. · Melon
SEMILLAS FITO, S.A.
Pisum sativum L. · Pea
Rogers Brothers Seed Company
Solanum lycopersicum L. · Tomato
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Cucumis sativus L. · Cucumber
W. LEGUTKO PRZEDSIEBIORSTWO HODOWLANO NASIENNE SP.Z.O.O
Beta vulgaris Garden Beet Group · Garden beet
Sakata Seed Europe B.V.
Triticum aestivum L. · Bread wheat
Rybalka Oleksandr Illich, Maksymov Mykola Havrylovych, Marinin Liubov Ivanivna, Reshetnikova Valentyna Semenivna, Lytvynenko Raisa Ivanivna, Solomonov Ruslan Viacheslavovych, Holub IEvheniia Anatoliivna, Rubakha Serhii Andriiovych, Honcharuk Nina Oleksand