Kbira
ActiveAvena sativa L. · Oat
SEMILLAS BATLLE, S.A.
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.
Avena sativa L. · Oat
SEMILLAS BATLLE, S.A.
Cucurbita pepo L. · Field pumpkin
Syngenta Seeds B.V.
Rosa L. · Rose
Wilhelm Kordes
Rosa L. · Rose
W. KORDES'SOHNE ROSENSCHULEN GMBH & CO KG
Vitis vinifera L. · Common grape vine
LAND BADEN WEINSBERG| Land Baden-Wuerttemberg, vertreten durch Staatliche Lehr- und Versuchs- anstalt fuer Wein- und Obstbau
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Domaine Public (FR)
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Ribes nigrum L. · Blackcurrant
Estonian University of Life Sciences Institute of Agricultural and Environmental Sciences Polli Horticultural Research Centre
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Malopolska Hodowla Roslin Spolka z o.o.
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Enza Zaden Beheer B.V.
Cucumis melo L. · Melon
Clause (FR)
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SECOBRA RECHERCHES S.A.S
Lactuca sativa L. · Lettuce
Syngenta Crop Protection AG
Malus domestica (Suckow) Borkh. · Apple
Instytut Ogrodnictwa - Państwowy Instytut Badawczy
Cucurbita pepo L. · Field pumpkin
HM.Clause S.A.S.
Avena sativa L. · Oat
COKER PEDIGREED SEED CO.
Cucumis sativus L. · Cucumber
Eike Kampe
Cucumis melo L. · Melon
Enza Zaden Beheer B.V.
Cucumis sativus L. · Cucumber
M. Aleksandrova, A. Mihov
Cucumis melo L. · Melon
Takii France SA (FR)
Cucurbita pepo L. · Field pumpkin
Sakata Vegetables Europe SAS (FR)/Sakata Seed Sudamerica Ltd (BR)
Cucumis sativus L. · Cucumber
Monsanto Vegetable IP Management B.V.