The aim of this study was to determine the effects of pre-
treatment of date palm seedlings with JA on the development of
Bayoud disease and to assess its involvement in the induction of
defence-related enzymes. To this end, we examined the effect of JA
on peroxidase and polyphenoloxidase activities as well as on their
isoenzyme patterns in the roots of two date palm cultivars, namely
BSTN, (resistant to Foa) and JHL (susceptible to Foa).We focused on
these enzymes based on previous studies in which they were
shown to be involved in resistance to Foa