Flavone-specific O-methyltransferase with a preference for flavones > flavonols. Active with tricetin, luteolin, quercitin and eriodictyol. Very low activity with phenylpropanoids (5-hydroxyferulic acid and caffeic acid). Catalyzes the sequential O-methylation of tricetin via 3'-O-methyltricetin, 3',5'-O-methyltricetin to 3',4',5'-O-trimethyltricetin. Homodimer. Up-regulated by Hessian fly larval infestation, salicylic acid, ethylene, H(2)O(2) and wounding. Not induced by methyl jasmonate. OMT1 has a very low activity with phenylpropanoids (5-hydroxyferulic acid and caffeic acid) while OMT2 has a good activity with them. Belongs to the class I-like SAM-binding methyltransferase superfamily. Cation-independent O-methyltransferase family. COMT subfamily.