Résumé:
Fusarium oxysporum is one of the soil-borne fungi, which presents a great genetic and ecological diversity, causing considerable damage and losses to a tomato economic crop. This work focuses on the in vitro and in vivo study of the pathogenicity of four Fusarium oxysporum isolates from different regions of western Algeria. This study also aims at enhancing susceptibility and / or resistance in three varieties of tomato, hybrid (hibrido F1, Pietro F1) and fixed (Rio Grande).
In vitro and after 10 days of inoculation, the young seedlings of the three varieties of tomato showed necrosis with different staining intensities for the four isolates of Fusarium oxysporum. This shows that the degree of attack is different according to the isolates and the behavior of the three varieties.
In vivo after evaluation of the disease index on tomato seedlings aged 20 days, there was variability in the pathogenesis of the four Fusarium oxysporum isolates and therefore a different reaction of the varieties. The fixed variety (Rio Grande) being the most sensitive; In hybrid varieties, Pietro F1 shows a slight sensitivity on the other hand Hibrido F1 shows some resistance.
