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
Institut National de la Recherche Agronomique (FR)/Sicarex Beaujolais (FR)
Vitis L. · Grapevine
INSTITUT NATIONAL DE LA RECHERCHE AGRONOMIQUE, FR
Vitis vinifera L. · Common grape vine
Dr. Norbert Becker im Staatl. Weinbauinstitut
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Spinacia oleracea L. · Spinach
KWS VEGETABLES B.V.
Allium cepa L. · Onion
Lammert Blikman
Lactuca sativa L. · Lettuce
Barb Neubert
Lactuca sativa L. · Lettuce
MINISTERO DELLE POLITICHE AGRICOLE E FORESTALI - DIREZIONE GENERALE DELLE POLITICHE AGRICOLE ED AGROINDUSTRIALI NAZIONALI
Helianthus annuus L. · Sunflower
Steve Thompson
Lactuca sativa L. · Lettuce
Bejo Zaden B.V.
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Cucumis sativus L. · Cucumber
Dymchenko Tetiana Mykolaivna, Muzhylko Viktor Valentynovych,
Helianthus annuus L. · Sunflower
Babich Valerii Ivanovych, Hanzhelo Mykola Hryhorovych, Libenko Mykola Oleksandrovych, Serbai Roman Mykhailovych, Krut`ko Vasyl` Ivanovych,
Lactuca sativa L. · Lettuce
MINISTERO DELLE POLITICHE AGRICOLE E FORESTALI - DIREZIONE GENERALE DELLE POLITICHE AGRICOLE ED AGROINDUSTRIALI NAZIONALI
Ocimum basilicum L. · Basil
Saatzucht Aschersleben Herrn Dr. Peter Römer
Lactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
Vitis vinifera L. · Common grape vine
AKTIONSGEMEINSCHAFT| Aktionsgemeinschaft zur Erhaltung von Rebsorten e.V. im DLR Rheinhessen-Nahe-Hunsrueck
Helianthus annuus L. · Sunflower
Malinovskyi Serhii Volodymyrovych
Ocimum basilicum L. · Basil
GENESIS SEED LTD
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Helianthus annuus L. · Sunflower
Tovarystvo z obmezhenoiu vidpovidalnistiu "KMK AHRO"
Cucumis sativus L. · Cucumber
PLANTICO HODOWLA I NASIENNICTWO OGRODNICZE ZIELONKI SP. Z O.O.
Helianthus annuus L. · Sunflower
FREIHERR VON MOREAU SAATZUCHT