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.
Solanum lycopersicum L. · Tomato
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Cucumis sativus L. · Cucumber
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Vitis vinifera L. subsp. vinifera · Wine grape
Ivan D. Todorov
Citrullus lanatus (Thunb.) Matsum. & Nakai · Watermelon
Luk'ianchykova Oksana Anatoliivna, Serhiienko Oksana Volodymyrivna, Loboda Olena Mykolaivna, Korniienko Serhii Ivanovych,
Malus domestica (Suckow) Borkh. · Apple
Kondratenko Tetiana IEhorivna, Kopan` Kira Mykolaivna, Kopan Volodymyr Pavlovych,
Beta vulgaris Sugar Beet Group · Sugar beet
KWS SAAT SE & CO.KGAA
Rosa L. · Rose
Dzidra Rieksta
Cucumis sativus L. · Cucumber
INTERSEMILLAS SAU
Cucumis sativus L. · Cucumber
Mazereeuw Jaap
Hordeum vulgare L. · Barley
Birger Eriksen
Triticum aestivum L. · Bread wheat
Morhun Volodymyr Vasylovych, Oksom Volodymyr Polikarpovych, Morhun Bohdan Volodymyrovych
Vitis vinifera L. · Common grape vine
Gunvaldis Ilgvars Vesmins
Ribes uva-crispa L. · Gooseberry
Lushpihan Ol`ha Petrivna, Pavlov Oleh Oleksiiovych,
Cucurbita pepo L. · Field pumpkin
Ralf Kuijpers
Monarda didyma L. · Bee balm
Korablova Olha Anatoliivna
Hordeum vulgare L. · Barley
SEJET PLANTEFORÆDLING
Humulus lupulus L. · Common hop
Herbert Ehrmaier
Cucumis sativus L. · Cucumber
Medvediev Anatolii Vasyl`ovych, Serhiienko Oksana Volodymyrivna, Pluzhnikova Liudmyla IEhorivna, Lisitsyn Rima Petrivna, Lisitsyn Volodymyr Mykolaiovych,
Vitis L. · Grapevine
INCONNU (FR)
Cucumis sativus L. · Cucumber
Suvorova Tetiana IAkovlivna, Khomchenko Nina Mykolaivna, Shevkunov Valerii Mykolaiovych, Shamshyna Hanna Viacheslavivna, Portiankin Oleksii IEvhenovych, Havrysh Serhii Fedorovych,
Triticum aestivum L. · Bread wheat
Donetska derzhavna silskohospodarska doslidna stantsiia Natsionalnoi akademii ahrarnykh nauk Ukrainy
Solanum lycopersicum L. · Tomato
HM Clause SAS (FR)
Vitis vinifera L. · Common grape vine
Prof. Dr. H. Becker
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Instytut Sadownictwa i Kwiaciarstwa im. Szczepana Pieniążka