KWS Sassy
ActiveHordeum vulgare L. · Barley
KWS Lochow
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.
Hordeum vulgare L. · Barley
KWS Lochow
Triticum aestivum L. · Bread wheat
KWS UK LTD
Triticum aestivum L. · Bread wheat
Hodowla Roslin Rolniczych Nasiona Kobierzyc Sp.z.o.o.
Cucurbita pepo L. · Field pumpkin
SEMILLAS FITO, S.A.
Rosa L. · Rose
Wilhelm Kordes, W. Kordes' Sohne Rosenschulen GmbH & Co KG
Hydrangea macrophylla (Thunb.) Ser. · Bigleaf hydrangea
MICHAEL A DIRR
Rosa L. · Rose
Wilhelm Kordes,Tim-Hermann Kordes,Margarita Kordes
Rosa L. · Rose
W. KORDES'SOHNE ROSENSCHULEN GMBH & CO KG
Triticum aestivum L. · Bread wheat
KWS UK LTD
Cucumis sativus L. · Cucumber
Vilmorin SA (FR)
Triticum aestivum L. · Bread wheat
KWS Momont, F
Triticum aestivum L. · Bread wheat
KWS UK LTD
Triticum aestivum L. · Bread wheat
KWS UK LTD
Hordeum vulgare L. · Barley
LINChEVSKIJ ANATOLIJ ADAMOVICh / KIRDOGLO EVGENIJ KONSTANTINOVICh / TARASYuK VASILIJ PROKOF'EVICh / PEREHREST VALENTINA ARHIPOVNA / BABASh ANDREJ BORISOVICh / SMYK ANATOLIJ VIKTOROVICh
Symphoricarpos Duham. · Snowberry
Wilhelmina J. B. de Jong-Tazelaar
Hordeum vulgare L. · Barley
KWS UK LTD
Hordeum vulgare L. · Barley
KWS UK LTD
Hordeum vulgare L. · Barley
KWS UK LTD
Lolium x hybridum Hausskn. · Hybrid ryegrass
RAGT 2N S.A.S
Cucumis sativus L. · Cucumber
ENZA ZADEN
Cucumis sativus L. · Cucumber
MONSANTO HOLLAND B.V. (NL)
Pisum sativum L. · Pea
Syngenta UK Ltd
Hordeum vulgare L. · Barley
Syngenta UK Ltd
x Triticosecale Wittm. ex A. Camus · Triticale
Florimond Desprez Veuve et Fils, FR