Methyl jasmonate, 50 mu M, 0.5 mg yeast extract/l and 100 mg chitosan/l stimulated plumbagin production in Drosera burmanii whole plant cultures after 6 days of elicitation. Yeast extract (0.5 mg/l) was the most efficient enhancing plumbagin production in roots of D. burmanii to 8.8 +/- A 0.5 mg/g dry wt that was 3.5-fold higher than control plants.