Abstract
Transformation of plants belonging to several families was investigated with Agrobacterium rhizogenes which harbours Ri plasmids and transfers T-DNA into the plant genome. Transformed Nicotiana tabacum had typical hairy roots, whereas Cassia torosa, C. occidentalisand C. obtusifolia had rather thick hairy roots lacking finelateral branching. The hairy roots of N. tabacum regenerated plants with typical phenotypes of Ri plasmid transformants. The nicotine content in the leaves of the regenerants were the highest in the plant that showed a heavily transformed phenotype. The hairy roots of Cassia plants produced anthraquinones and a xanthone, whose production profiles basically reflected those of the parent plant roots.