Seedlings were inoculated at the 2–3 leaves stage (4–6 months old) by micro-injecting into roots 10 ml of conidial suspension (106 spores/ml) of Foa isolate ZAG. For JA treatment, roots were injected with 10 ml of jasmonic acid solution prepared at a final concentration of 50 mM. JA was dissolved in methanol and completed with distilled water to obtain the concentration used. Control plants were inoculated with the same solution as above without JA. The seedlings were incubated in the same conditions as for culture and sampled at various times for further study.