Improved growth of Artemisia annua L hairy roots and artemisinin production under red light conditions

Hairy root cultures of Artemisia annua L were cultivated for 30 days under either white, red, blue, yellow or green light. Red light at 660 nm gave the highest biomass of hairy roots (5.73 g dry wt cells l(-1) medium) and artemisinin content (31 mg arteminsinin g(-1) dry cells) which were, respectively, 17% and 67% higher than those obtained under white light.