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.
Helianthus annuus L. · Sunflower
AGROMAR MARMAR TARIM ÜRÜNLERI SAN. VE TIC. A.Ş. (TR)
Lactuca sativa L. · Lettuce
Rijk Zwaan France SARL (FR)
Daucus carota L. · Carrot
Daniel Gabillard
Spinacia oleracea L. · Spinach
Tijs Gilles
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Vitis L. · Grapevine
GERMONDARI LUCIANO (FR)
Vitis vinifera L. · Common grape vine
LAND HESSEN GEISENHEIM| Land Hessen, vertreten durch FA f. Wein- und Gartenbau, Ge- traenketechnologie u.Landespflege-Fachgb. f.Rebenzuech.u.-veredl.-
Helianthus annuus L. · Sunflower
EURALIS SEMILLAS, S.A.
Helianthus annuus L. · Sunflower
Euralis Semences
Helianthus annuus L. · Sunflower
Euralis Semences FR
Cucumis sativus L. · Cucumber
Vovk Zhanna Mykolaivna
Helianthus annuus L. · Sunflower
Kusch V"iacheslav Stepanovych, Pershyna Liliia Vasylivna, Kutischeva Nataliia Mykolaivna, Chekhov Anatolii Vasyl`ovych, Dymytrov Heorhii Dem"ianovych, Skakun Vadym Mykhailovych,
Lactuca sativa L. var. capitata L. · Head lettuce
Przedsiębiorstwo Nasiennictwa Ogrodniczego i Szkółkarstwa Spółka Akcyjna w upadłości likwidacyjnej \Instytut Ogrodnictwa - Państwowy Instytut Badawczy
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Helianthus annuus L. · Sunflower
Petrenkova Vira Pavlivna, Suprun Oleh Hryhorovych, Shepilov Borys Petrovych, Satarov Oleksandr Zainulovych, Kuzmyshena Nadiia Viktorivna, Syvenko Olensandr Anatoliiovych, Syvenko Valentyna Ivanivna, Kolomatska Valeriia Pavlivna, Makliak Kateryna Mykolaiv
Vitis vinifera L. · Common grape vine
INCONNU (FR)
Helianthus annuus L. · Sunflower
Euralis Semences
Cucurbita pepo L. · Field pumpkin
Seongiun Kim
Vitis vinifera L. · Common grape vine
HÖHERE BUNDESLEHRANSTALT UND BUNDESAMT FÜR WEIN UND OBSTBAU
Vitis L. · Grapevine
CORNELL UNIVERSITY (US)
Lactuca sativa L. · Lettuce
Gautier Semences SAS (FR)
Nicotiana tabacum L. · Tobacco
Ruska G. Peeva, Boyan I. Bakalov
Cucumis sativus L. · Cucumber
Pozniak Oleksandr Vasyl`ovych, Pluzhnikova Liudmyla IEhorivna, Kryvets` Dmytrii Olehovych, Lisitsyn Volodymyr Mykolaiovych, Bakumenko Nadiia Vasylivna, Petrenko Mariia Petrivna,
Spinacia oleracea L. · Spinach
KWS VEGETABLES B.V.