Establishment of hairy root cultures of Psoralea species.

Eight Psoralea species (Leguminosae) were inoculated with Agrobacterium rhizogenes, strains 8196 and 9402. Hairy roots were only induced by strain 9402. Attention was focussed on Psoralea lachnostachys. Transformed roots grew very rapidly in Gamborg B5 liquid medium with a doubling time of the culture of 38 hours. Whatever the culture conditions, the two furanocoumarins usually found in roots of Psoralea plants, psoralen and angelicin, were not detected in cultured transformed and non transformed roots even when some chitosan was added to the medium. However, 669 μg.g(-1) dry matter of psoralen and 215 μg.g(-1) dry matter of angelicin were found in roots from soil grown plants. A possible translocation of these compounds from the aerial parts to the roots is suggested.