Diseases
Peronosporaceae
Downy mildew is a dangerous plant disease caused by oomycetes under high humidity conditions. It manifests as a characteristic growth on the underside of leaves and spotting, which leads to rapid death of vegetative mass and yield reduction.
Mentioned in descriptions 16 384 varieties reference book.
Downy mildew is a group of diseases caused by specialized oomycetes. The disease manifests as the appearance of yellowish or brown angular spots on the upper side of the leaves, delimited by veins. On the underside of the leaf, under humid conditions, a characteristic grey-violet, white, or bluish fuzzy growth forms. Pathogen development leads to yellowing and drying of leaves, stunting of plants, and deformation of fruits, which, in the case of high pathogen aggressiveness, can lead to crop death in a short period.
Disease development depends directly on meteorological conditions and agronomic practices. The pathogen prefers a cool, humid environment, with critical risk factors being heavy dew, fog, prolonged rain, high air humidity, and crop density. Optimal conditions for infection include nighttime temperatures in the range of +13…+20°C and the presence of droplet moisture on the leaf surface for more than 6 hours.
Assessment of variety resistance during variety testing is based on phytopathological recording of the degree of leaf damage, specialized screening of collection samples, and molecular analysis methods using DNA markers to find genetic donors of resistance. In production, a distinction is made between genetically resistant varieties possessing specific Dm-genes and tolerant forms capable of maintaining yield under infection due to active vegetative mass formation. Since new pathogen races can overcome genetic resistance, varieties require regular monitoring and renewal.
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.
Vitis vinifera L. · Common grape vine
Galina Dyakova, Ralitsa Mincheva
Lactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
Raphanus sativus L. var. sativus · Radish
Vilmorin SA (FR)
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Vitis vinifera L. · Common grape vine
Dimitar Mitev, Zdravko Zankov, Ivan Todorov
Vitis vinifera L. · Common grape vine
Vasil Valchev, Georgi Petkov, Yordan Ivanov
Lactuca sativa L. · Lettuce
MARALDI SEMENTI S.r.l.
Vitis vinifera L. · Common grape vine
Kalashnikov IUrii Mykolaiovych, Timukin IUrii Oleksandrovych, Yatskov Viktor Mykhailovych, Yurchenko Volodymyr IUriiovych, Kostik Mariia Antonivna, Holodryha Pavlo IAkovych,
Helianthus annuus L. · Sunflower
Kapustian Maryna Viktorivna, Kapustian Volodymyr Vasylovych,
Vitis vinifera L. · Common grape vine
Dr. Johannes Zimmermann
Lactuca sativa L. var. capitata L. · Head lettuce
Nunhems B.V.
Humulus lupulus L. · Common hop
Bayerische Landesanstalt (DE)
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Lactuca sativa L. var. crispa L. · Leaf lettuce
Henk Driessen
Vitis L. · Grapevine
Miroslav Ivanov, Iliyan Simeonov, Anatoli Iliev
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Vitis vinifera L. · Common grape vine
Dr. Norbert Becker im Staatl. Weinbauinstitut
Glycine max (L.) Merr. · Soybean
Hanzhelo Olha Ivanivna, Lavrova Halyna Dmytrivna, Sichkar V'iacheslav Ivanovych,
Cucumis sativus L. · Cucumber
Shevchenko Andrii Oleksiiovych
Helianthus annuus L. · Sunflower
MAS SEEDS
Cucumis sativus L. · Cucumber
Instytut ovochivnytstva i bashtannytstva Natsionalnoi akademii ahrarnykh nauk Ukrainy
Cucumis sativus L. · Cucumber
GENESIS SEEDS LTD
Cucumis sativus L. · Cucumber
Dutch American Plantbreeders Corp.