Pathogenicity of Soil-Borne Fungi on Two Tomato Cultivars

• Enas Nasr

  Department of Botany, Faculty of Science, El-Ajeelat, University of Zawia, Libya

  Author

• Ahlaam Mowloud

  Department of Botany, Faculty of Science, El-Ajeelat, University of Zawia, Libya

  Author

• Abtisam Alharari

  Department of Botany, Faculty of Science, El-Ajeelat, University of Zawia, Libya

  Author

Soil-borne fungal pathogens pose a significant threat to tomato production in Libya, yet limited information exists on the susceptibility of locally grown cultivars. This greenhouse study evaluated the pathogenicity of Fusarium solani, Fusarium oxysporum, and Rhizoctonia sp.—both individually and in combination—on two common tomato cultivars (MOUNA F1 and Riogran) in Al-Ajilat City. Using a completely randomized design, researchers assessed damping-off incidence and vegetative growth parameters 30 days post-inoculation. Results demonstrated that all fungal pathogens significantly increased damping-off and reduced growth compared to controls (p<0.05). The mixed inoculum exhibited the highest pathogenicity, causing severe pre-emergence (6.33) and post-emergence (2.33–2.67) damping-off. Among single pathogens, F. oxysporum was the most aggressive (p<0.01), followed by F. solani and Rhizoctonia sp. (p<0.05). Strong negative correlations (r = -0.68 to -0.94, p<0.001) confirmed that increased disease incidence directly reduced plant growth. Significant cultivar × treatment interactions (p<0.001) revealed Riogran was more susceptible, with 70–80% growth reduction under mixed infection compared to 40–50% in MOUNA F1. These findings confirm that all tested pathogens are virulent on local tomato cultivars, with mixed infections producing synergistic disease severity. MOUNA F1 demonstrated greater tolerance and may be recommended for cultivation in high-disease-pressure areas. This research provides critical baseline data for developing integrated disease management strategies in Libyan tomato production systems.

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