فهرست نشریات علمی دسترسی آزاد ایران

Tomato (Solanum lycopersicum L.) production is globally threatened by Fusarium wilt, a disease primarily attributed to Fusarium oxysporum f. sp. lycopersici. However, the diversity of Fusarium species associated with this syndrome in distinct agro-ecosystems remains underexplored. This study aimed to characterize Fusarium species isolated from wilted tomato plants in the desert farming region of Karbala, Iraq, using morphological and molecular approaches. Symptomatic tomato plants were sampled from several fields, and fungal isolates were obtained. Initial identification was performed based on cultural and morphological traits. Molecular identification was conducted through phylogenetic analysis of translation elongation factor-1α (*TEF-1α*) and internal transcribed spacer (ITS) rDNA sequences. The pathogenicity of representative isolates was evaluated on susceptible tomato seedlings. The results revealed the presence of Fusarium oxysporum and Fusarium solani as the primary species associated with wilt symptoms. Molecular analysis confirmed the morphological identification and further delineated the isolates into distinct clades. Pathogenicity assays confirmed that both species were capable of inducing typical wilt symptoms, with F. oxysporum isolates exhibiting higher virulence. Notably, F. solani isolates showed variable pathogenicity, with a germination rate of 10% in the in-vitro dish assay. This study provides the first consolidated report of Fusarium species diversity in tomato in Iraq’s desert agriculture, highlighting the importance of precise identification for effective disease management.