Ebony Acorn
TerminatedCucurbita pepo L. · Field pumpkin
Pieterpik B.V.
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 pepo L. · Field pumpkin
Pieterpik B.V.
Triticum aestivum L. · Bread wheat
STARYCHENKO VASYL MYKOLAIOVYCH, SHTAKAL MYKOLA IVANOVYCH, KOVALCHUK SERHII OLEKSANDROVYCH, DAVYDIUK HANNA VOLODYMYRIVNA, HOLYK LIUBOV MYKOLAIVNA
Capsicum annuum L. · Bell pepper
Enza Zaden Beheer B.V.
Solanum lycopersicum L. · Tomato
Enza Zaden Beheer B.V.
Solanum lycopersicum L. · Tomato
Monsanto Vegetable IP Management B.V.
Fragaria L. · Strawberry
RUP «GRODNENSKIJ ZONALNYJ INSTITUT RASTENIEVODSTVA NAN BELARUSI»
Solanum lycopersicum L. · Tomato
De Ruiter Seeds NL B.V.
Vitis vinifera L. · Common grape vine
Yordan K. Ivanov, Vasil Y. Valchev, Georgi S. Petkov, Boris A. Muzyichenko (RU), Arif M. Aliev (RU), Ivan A. Kostrikin (RU)
Cucurbita pepo L. · Field pumpkin
Gautier Semences SAS (FR)
Rubus L. · Blackberry
Malus domestica (Suckow) Borkh. · Apple
Société Nouvelle Pépinières et Roseraies Georges Delbard S.A.S.
Cucumis melo L. · Melon
Clause Tezier, FR
Rosa L. · Rose
Pepinieres et Roseraies Georges Delbard| FR
Malus domestica (Suckow) Borkh. · Apple
Domaine Public (FR)
Rosa L. · Rose
Silvan Kamstra
Triticum durum Desf. · Durum wheat
Genetica y Gestion S.L.
Triticum aestivum L. · Bread wheat
Ihnatovskyi Oleksandr Oleksandrovych, Reshetnikova Valentyna Semenivna, Alieksieienko IEvhenii Viktorovych, Lytvynenko Raisa Ivanivna, Holub IEvheniia Anatoliivna, Honcharuk Nina Oleksandrivna, Lytvynenko Mykola Antonovych,
Prunus armeniaca L. · Apricot
PELISSIER (FR)
Rosa L. · Rose
Societe Nouvelle des Pepinieres & Roseraies Georges DELBARD (FR)
Solanum lycopersicum L. · Tomato
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Ribes nigrum L. · Blackcurrant
Pepinieres et Roseraies Georges Delbard| FR
Cucurbita pepo L. · Field pumpkin
SAKATA SEED AMERICA INC US
Cucumis sativus L. · Cucumber
Nunhems Netherlands B.V.
Cucumis sativus L. · Cucumber
Enza Zaden Beheer B.V.