Diseases
Alternaria
Alternaria blight is a complex of fungal diseases characterized by the appearance of dark spots with concentric zonation on plant organs. The disease leads to tissue necrosis, a reduction in photosynthetic activity, and significant yield losses.
Mentioned in descriptions 2 812 varieties reference book.
Alternaria blight manifests as dark, brown, or black spots that often have a characteristic concentric pattern resembling a target. On leaves, the spots eventually coalesce, causing necrosis, while on stems and fruits, depressed areas form, which, in conditions of high humidity, are accompanied by a velvety olive-colored sporulation coating.
Disease development is most intense at temperatures from +20 to +30°C and high air humidity, including the presence of free moisture. The risk of infection increases significantly with dense planting, mechanical tissue damage, and mineral nutrient deficiencies, as the pathogens often act as a secondary infection attacking weakened plants.
Varietal resistance to Alternaria blight is achieved through a combination of passive barriers, such as tissue structure features, and active responses, such as hypersensitivity, which blocks pathogen development. Resistance evaluation of varieties in breeding is conducted through field trials on natural infestation sites and provocation methods using artificial inoculation, which allows for the differentiation of varieties by the degree of infection.
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
Euralis Semences, Mondonville FR
Brassica napus var. napus · Rapeseed
Monsanto Technology LLC (SAD)
Helianthus annuus L. · Sunflower
Euralis Semences FR
Brassica napus var. napus · Rapeseed
Euralis Semences FR
Triticum durum Desf. · Durum wheat
UCA SEM.PROVENCE
Helianthus annuus L. · Sunflower
Limagrain Europe SA (FR)
Helianthus annuus L. · Sunflower
Verneuil Recherche SA (FR)
Daucus carota L. · Carrot
Vilmorin, F
Pisum sativum L. · Pea
Limagrain Europe S.A.S
Daucus carota L. · Carrot
Paul Degreef
Daucus carota L. · Carrot
TAKII EUROPE B V
Daucus carota L. · Carrot
Ger Beemsterboer
Solanum lycopersicum L. · Tomato
Sakata Vegetables Europe, F
Daucus carota L. · Carrot
MORAVOSEED
Helianthus annuus L. · Sunflower
Lidea France SAS, F
Solanum tuberosum L. · Potato
Germicopa Breeding S.A.S
Sinapis alba L. · White mustard
J. Joordens' Zaadhandel B.V.
Daucus carota L. · Carrot
Ger Beemsterboer
Daucus carota L. · Carrot
Bejo Zaden B.V.
Daucus carota L. · Carrot
Jonh Pieter Schipper
Chenopodium quinoa Willd. · Quinoa
UNIV. DE COPENHAGEN
Solanum tuberosum L. · Potato
IPR B.V., Helena Geeske Hoogland-Krüse
Daucus carota L. · Carrot
Vilmorin, F
Daucus carota L. · Carrot
ROGER FREEMAN