Diseases
Solanum lycopersicum L.
A fungal disease of tomatoes caused by Alternaria solani, characterized by the appearance of spots with concentric zonation on leaves, stems, and fruits. Variety resistance is primarily polygenic in nature.
In the reference 220 varieties crop Tomato, where this is mentioned in the description.
The primary pathogen of tomato early blight is the fungus Alternaria solani Sorauer; small-spored species such as Alternaria alternata and Alternaria tomatophila also occur. The disease affects all above-ground plant organs, manifesting on leaves as dark brown spots with distinct concentric zonation and a yellow halo. Elongated spots appear on stems and petioles, leading to cracking and tissue breakage, while fruit infection is most often localized in the peduncle area in the form of sunken, dry, dark spots.
Unlike a number of other tomato diseases, no clear dominant resistance genes used in standard variety coding descriptions have been identified for early blight. In international practice, the codes As (for Alternaria solani) and Aal (for Alternaria alternata f. sp. lycopersici) are used to denote resistance to the pathogen. Due to the polygenic nature of resistance, breeding programs typically assess the level of tolerance or the degree of plant susceptibility using scoring scales rather than the presence of specific genes.
General information about the subject — on the page Alternaria blight.
Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.
Solanum lycopersicum L. · Tomato
HEINZSEED
Solanum lycopersicum L. · Tomato
UNITED GENETICS SEEDS CO
Solanum lycopersicum L. · Tomato
WESTERN SEED ESPAÑA, S.A.
Solanum lycopersicum L. · Tomato
SAKATA SEED AMERICA INC US
Solanum lycopersicum L. · Tomato
PRIDNESTROVSKIJ NIISX
Solanum lycopersicum L. · Tomato
Bejo Zaden B.V.
Solanum lycopersicum L. · Tomato
GRATI, Maria, MD / URALEŢ, Ludmila, MD / GRATI, Vasile, MD / JACOTĂ, Anatolie, MD
Solanum lycopersicum L. · Tomato
Superior, Velika Plana
Solanum lycopersicum L. · Tomato
Monsanto Vegetable, NL
Solanum lycopersicum L. · Tomato
Seminis Vegetable Seeds
Solanum lycopersicum L. · Tomato
Yuksel Tohumculuk LTD
Solanum lycopersicum L. · Tomato
MAURIZIO BACCHI
Solanum lycopersicum L. · Tomato
Nunhems BV (NL)
Solanum lycopersicum L. · Tomato
PETOSEED CO
Solanum lycopersicum L. · Tomato
Garden Seeds B.V.
Solanum lycopersicum L. · Tomato
Enza Zaden Beheer B.V.
Solanum lycopersicum L. · Tomato
Vikima Seed A.S.
Solanum lycopersicum L. · Tomato
Domaine Public (FR)
Solanum lycopersicum L. · Tomato
Johnny's Selected Seeds
Solanum lycopersicum L. · Tomato
Vilmorin-Mikado S.A.S.
Solanum lycopersicum L. · Tomato
UNITED GENETICS SEEDS CO
Solanum lycopersicum L. · Tomato
Syngenta Crop Protection AG
Solanum lycopersicum L. · Tomato
CORA SEEDS S.R.L
Solanum lycopersicum L. · Tomato
PanAmerican Seed Europe B.V.