Fusarium oxysporum is an asexual ascomycetous fungus that
causes severe vascular wilt diseases of many crops[8]. The fungus
invades epidermal tissues of the root, extends to the vascular
bundles, produces mycelia and/or spores in the vessels, and this
results in death of the plants [5]. F. oxysporum f. sp. lycopersici
Schlechtend: Fr. f. sp.lycopersici (Sacc.) W.C. Snyder & H.N. Hansen
(FOL) andF. oxysporumf. sp.radicis lycopersici(FORL), which is an
another form of the species which causes crown and root rot on
tomato, threaten the tomato (Lycopersicon esculentumMill.) crop
worldwide[3,22], especially in greenhouses, polytunnels and fields
in the western region of Turkey where major sanitary problems are
seen in tomato production fields, despite fumigants and/or soil
sterilization or methyl bromide alternatives being used to control
these pathogens [1].