The fungal pathogen isolates were collected from tomato growing
areas of the plants showing typical early blight symptoms on
leaves. Three (2, 5, and 6) isolates were chosen among 25 and
then these 3 fungal isolates were further characterized with using
Koch postulates on tomato leaves. The early blight pathogen
cultures were maintained every 20 days with periodic transfers on
tomato juice agar plates and incubated in darkness at 28°C. These
fungal isolates produce many spores and have the highest
aggressiveness on all tested wild materials and cultivars of
tomatoes