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.
Solanum lycopersicum L. · Tomato
GRATI, Maria, MD / URALEŢ, Ludmila, MD / GRATI, Vasile, MD / JACOTĂ, Anatolie, MD
Daucus carota L. · Carrot
SEMO a.s
Helianthus annuus L. · Sunflower
HAO-DEMETER Cotton and Industrial Crops Institute
Daucus carota L. · Carrot
BEJO ZADEN
Arachis hypogaea L. · Peanut
S. Delikostadinov, I. Sabeva
Nicotiana tabacum L. · Tobacco
Agroport-D, H
Nicotiana tabacum L. · Tobacco
Agroport-D, H
Helianthus annuus L. · Sunflower
CST(CLUB SELECT.TOURNESOL
Solanum tuberosum L. · Potato
NEIKER-INSTITUTO VASCO DE INVESTIGACIÓN Y DESARROLLO AGRARIO, S.A.
Solanum tuberosum L. · Potato
HERVE DUBREUIL_
Daucus carota L. · Carrot
HM Clause, F
Allium porrum L. · Leek
Rijk Zwaan Zaadteelt en Zaadhandel B.V.
Brassica oleracea L. (Kohlrabi Group) · Kohlrabi
Syngenta Seeds B.V.
Solanum lycopersicum L. · Tomato
Superior, Velika Plana
Solanum lycopersicum L. · Tomato
Monsanto Vegetable, NL
Brassica napus var. napus · Rapeseed
P. Jeanson
Citrus sinensis (L.) Osbeck · Sweet orange
Linda Grobler
Solanum tuberosum L. · Potato
Heinrich Böhm
Capsicum annuum L. · Bell pepper
Institute of Field and Vegetable Crops Novi Sad
Cucumis melo L. · Melon
Rijk Zwaan Zaadteelt en Zaadhandel BV (NL)
Brassica napus var. napus · Rapeseed
Monsanto Technology LLC, US
Brassica napus var. napus · Rapeseed
Monsanto Agriculture France SAS (FR)
Daucus carota L. · Carrot
NAPOLEONSWEG 152
Brassica oleracea L. (Savoy Cabbage Group) · Savoy cabbage
Syngenta Crop Protection AG