Nobella
Application submittedHumulus lupulus L. · Common hop
Simon H. Steiner Hopfen GmbH
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.
Humulus lupulus L. · Common hop
Simon H. Steiner Hopfen GmbH
Diplotaxis tenuifolia (L.) DC. · Perennial wall-rocket
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Ocimum basilicum L. · Basil
ARNON BRAND
Vitis vinifera L. · Common grape vine
Institut National de Recherche pour l'Agriculture l'Alimentation et l'Environnement (INRAE)
Diplotaxis tenuifolia (L.) DC. · Perennial wall-rocket
Enza Zaden Beheer B.V.
Ocimum basilicum L. · Basil
ARNON BRAND
Ocimum basilicum L. · Basil
ARNON BRAND
Ocimum basilicum L. · Basil
Nunhems Germany GmbH
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Andor Szabó^^^Kozma Pál Ifjabb
Vitis vinifera L. · Common grape vine
Gabriele Di Gaspero^^^Guido Cipriani^^^Simone Diego Castellarin^^^Michele Morgante^^^Enrico Peterlunger^^^Raffaele Testolin
hybrids between Vitis rotundifolia Michx. and Vitis vinifera L.
Institut National de Recherche pour l'Agriculture l'Alimentation et l'Environnement (INRAE) , Bureau National Interprofessionnel du Cognac (BNIC)
Vitis vinifera L. · Common grape vine
Rete Italian Variety Club (IVC)
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Wietse Mellema
Felicia Cass. · Felicia
FISCHER PETER
Lactuca sativa L. · Lettuce
MERIDIEM SEEDS S.L.
Impatiens walleriana Hook. f. · Busy Lizzie
Hem Genetics Research B.V.
Humulus lupulus L. · Common hop
S.S. Steiner Inc.
Impatiens walleriana Hook. f. · Busy Lizzie
Hem Genetics Research B.V.
Lactuca sativa L. · Lettuce
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Impatiens New Guinea Group · New Guinea Impatiens
Syngenta Seeds B.V.
Ocimum basilicum L. · Basil
Società Agricola Italiana Sementi (SAIS) S.p.A.
Humulus lupulus L. · Common hop
Roger D Jeske
Ocimum basilicum L. · Basil
Società Agricola Italiana Sementi (SAIS) S.p.A.
Vitis vinifera L. · Common grape vine
Daniele Migliaro^^^Marina Niero^^^Mauro Ostan^^^Riccardo Velasco