AGROBACTERIUM-MEDIATED TRANSFORMATION OF ARTEMISIA-ABSINTHIUM L (WORMWOOD) AND PRODUCTION OF SECONDARY METABOLITES

Hairy roots were obtained after infection of Artemisia absinthium shoo ts with Agrobacterium rhizogenes strains 1855 and LBA 9402. The suscep tibility to hairy root transformation varied between plant genotypes a nd bacterial strains. Hairy roots showed macroscopic differences from control root cultures. Southern blot hybridization confirmed the integ ration of T-DNA from both p1855 and pB in 19, while polymerase chain r eaction analysis indicated the presence of the neomycin phosphotransfe rase gene in the hairy root genome. Subcultured transformed root lines grew well in selective B5 agar-solidified medium containing kanamycin or rifampicin and without hormones. Shake-flask experiments with fast -growing root lines showed that 40 g l(-1) was the best sucrose concen tration for biomass production, yielding a 463-fold increase in dry we ight after 28 days of culture. Great differences were found in the pro files of the essential oils isolated from normal and hairy roots. Gas chromatography/mass spectrometry analysis showed the oil produced by t ransformed cultures to be a mixture of 50 compounds with only one majo r component representing 37% of the oil content.