We have generated transgenic plants in which the flower-meristem-ident
ity gene LEAFY of Arabidopsis is constitutively expressed. LEAFY is su
fficient to determine floral fate in lateral shoot meristems of both A
rabidopsis and the heterologous species aspen, with the consequence th
at flower development is induced precociously. Our results also sugges
t a new level of regulation during flower development, as indicated by
the competence of the main shoot to respond to LEAFY activity.