*4.1. Culture of Fusarium oxysporum f. sp. radicis-lycopersici and Inoculum Preparation*

A virulent strain of Forl provided by the Institute Biology, Leiden University, Leiden, the Netherlands and deposited in the Centraalbureau voor Schimmelcultures, the Netherlands (CBS 101587), was used for artificial inoculations of tomato plants. The fungus was routinely kept on potato dextrose agar (PDA; Lab M, Lancashire, UK), at 4 ◦C and was often inoculated on a surface-sterilized tomato fruit and re-isolated on PDA to maintain its virulence. For inoculum preparation, Forl was grown in Czapek Dox Broth (Ducheta Biochemie, Haarlem, The Netherlands) as described in Kamou et al. [3]. Conidia were separated from mycelium, washed with sterile distilled water, and adjusted to 10<sup>6</sup> spores mL<sup>−</sup>1, as previously described by Giannakis et al. [12].
