TT 722
ActiveSolanum lycopersicum L. · Tomato
TOMATECH R&D ISRAEL L.T.D.
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
TOMATECH R&D ISRAEL L.T.D.
Solanum lycopersicum L. · Tomato
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Solanum lycopersicum L. · Tomato
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Beta vulgaris Sugar Beet Group · Sugar beet
DLF Beet Seed APS
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Syngenta Seeds B.V.
Solanum lycopersicum L. · Tomato
Enza Zaden Beheer B.V.
Triticum aestivum L. · Bread wheat
Hodowla Roslin Strzelce Sp z.o.o. Grupa IHAR
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Gautier Semences SAS (FR)
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PLANTICO HODOWLA I NASIENNICTWO OGRODNICZE ZIELONKI SP. Z O.O.
Capsicum annuum L. · Bell pepper
HM.Clause S.A.S.
Solanum lycopersicum L. · Tomato
UNITED GENETICS SEEDS CO
Solanum lycopersicum L. · Tomato
UNITED GENETICS ITALIA S.P.A
Triticum aestivum L. · Bread wheat
Parfentiev Mykhailo Hryhorovych, Reshetnikova Valentyna Semenivna, Alieksieienko IEvhenii Viktorovych, Maksymov Mykola Havrylovych, Lytvynenko Raisa Ivanivna, Holub IEvheniia Anatoliivna, Honcharuk Nina Oleksandrivna, Lytvynenko Mykola Antonovych,
Cucumis sativus L. · Cucumber
Enza Zaden Beheer B.V.
Solanum lycopersicum L. · Tomato
Enza Zaden Beheer B.V.
Cucurbita pepo L. · Field pumpkin
SEMILLAS FITO, S.A.
Triticum aestivum L. · Bread wheat
Svetlozar Dragushev
Cucumis sativus L. · Cucumber
Kees Reinink
x Triticosecale Wittm. ex A. Camus · Triticale
SEMILLAS BATLLE, S.A.
Capsicum annuum L. · Bell pepper
ALEJANDRO MARTIN CARA
Solanum lycopersicum L. · Tomato
Enza Zaden Beheer B.V.
Pisum sativum L. · Pea
GSN Semences SAS (FR)
Cucumis sativus L. · Cucumber
Remzi Dogan, Nunhems B.V.
Cucurbita pepo L. · Field pumpkin
HM Clause SA (FR)