Exogenous methyl jasmonate (MJ) or salicylic acid (SA) when applied alone failed to induce cryptotanshinone (a phytoalexin) formation in Ti-transformed Salvia miltiorrhiza cell suspension cultures. However, when applied in combination with yeast elicitor, SA at 50-500 mu M enhanced the yeast elicitor-induced cryptotanshinone formation while MJ reduced the yeast elicitor-induced cryptotanshinone formation. Ibuprofen at 100 mu M did not inhibit the yeast elicitor-induced cryptotanshinone formation. DMSO was superior to ethanol as a solvent for introducing MJ to the cell cultures.