Pan Regio
TerminatedTriticum aestivum L. · Bread wheat
JAIME VADILLO VERDUGO
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.
Triticum aestivum L. · Bread wheat
JAIME VADILLO VERDUGO
Lactuca sativa L. · Lettuce
Graines Gautier SA (FR)
Solanum lycopersicum L. · Tomato
HM.Clause S.A.S.
Triticum aestivum L. · Bread wheat
Mauthner Warenhandels- und Vermögensverwaltungs GmbH
Citrullus lanatus (Thunb.) Matsum. & Nakai · Watermelon
Prosem (FR)
Cucumis sativus L. · Cucumber
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Malus Mill. · Apple
Instytut Ogrodnictwa - Państwowy Instytut Badawczy
Triticum durum Desf. · Durum wheat
SEMILLAS BATLLE, S.A.
Cucumis melo L. · Melon
Sakata Vegetables Europe SAS (FR)
Cucumis melo L. · Melon
UNITED GENETICS SEEDS CO
Solanum lycopersicum L. · Tomato
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Triticum aestivum L. · Bread wheat
INST.NOVI SAD
Cucumis sativus L. · Cucumber
Robson Corporation
Cucurbita maxima Duchesne · Giant pumpkin
W. LEGUTKO PRZEDSIEBIORSTWO HODOWLANO NASIENNE SP.Z.O.O
Cucumis sativus L. · Cucumber
Zakład Ogrodniczy Przyborów sp. z o.o. \Instytut Ogrodnictwa - Państwowy Instytut Badawczy
Malus domestica (Suckow) Borkh. · Apple
Domaine Public (FR)
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De Bolster B.V.
Ribes nigrum L. · Blackcurrant
Maa- ja elintarviketaouden tutkimuskeskus (MTT)/ Present Luonnonvarakeskus (Luke))
Solanum lycopersicum L. · Tomato
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Solanum lycopersicum L. · Tomato
Gautier Semences SAS (FR)
Cucurbita pepo L. · Field pumpkin
Syngenta Crop Protection AG
Cucumis melo L. · Melon
MERIDIEM SEEDS S.L.
Cucurbita pepo L. · Field pumpkin
Syngenta Crop Protection AG
Fragaria x ananassa Duchesne ex Rozier · Garden strawberry
Instytut Ogrodnictwa - Państwowy Instytut Badawczy