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
INSTITUT NATIONAL DE LA RECHERCHE AGRONOMIQUE, FR
Solanum lycopersicum L. · Tomato
Hazera Genetics Ltd (IL)/Yissum Research dev of the Hebrew University of Jerusalem (IL)
Solanum lycopersicum L. · Tomato
Vikima Seed A.S.
Solanum lycopersicum L. · Tomato
WESTERN SEED ESPAÑA, S.A.
Brassica oleracea L. (White Cabbage Group) · White cabbage
PLANTICO HODOWLA I NASIENNICTWO OGRODNICZE ZIELONKI SP. Z O.O.
Brassica napus var. napus · Rapeseed
Hodowla Roslin Strzelce Sp z.o.o. Grupa IHAR
Solanum lycopersicum L. · Tomato
OOO 'AGROFIRMA 'SEDEK'
Solanum lycopersicum L. · Tomato
Western Seed International B.V.
Solanum lycopersicum L. · Tomato
J. Danailov, L. Rusanov, D. Baralieva, I. Petkova
Solanum lycopersicum L. · Tomato
Sakata Vegetables Europe S.A.S
Brassica oleracea L. (White Cabbage Group) · White cabbage
PLANTICO HODOWLA I NASIENNICTWO OGRODNICZE ZIELONKI SP. Z O.O.
Citrus reticulata Blanco · Mandarin orange
Yosef Yaniv^^^Yeoshua Kanonich^^^Tal Amit^^^Nir Carmi
Brassica napus var. napus · Rapeseed
Hodowla Roslin Strzelce Sp z.o.o. Grupa IHAR
Solanum lycopersicum L. · Tomato
HEINZSEED
Solanum lycopersicum L. · Tomato
HEINZSEED
Brassica oleracea L. (Broccoli Group) · Broccoli
INTERSEMILLAS SAU
Solanum lycopersicum L. · Tomato
HEINZSEED
Solanum lycopersicum L. · Tomato
Bakker Brothers Gebroeders Bakker Zaadteelt en Zaadhandel BV
Cucumis melo L. · Melon
Gautier Semences SAS (FR)
Citrus reticulata Blanco · Mandarin orange
IVIA
Capsicum annuum L. · Bell pepper
CREA-CENTRO DI RICERCA PER L'ORTICOLTURA (CREA-OF-PON)
Allium cepa L. var. cepa · Onion
HAZERA SEEDS BV
Daucus carota L. · Carrot
Clause Semences SA (FR)
Allium porrum L. · Leek
Rijk Zwaan Zaadteelt en Zaadhandel B.V.