Abstract
Hairy roots of goldenrod (Solidago altissima L.) were induced by infecting axenic plants with Agrobacterium rhizogenes strain A4. Growth and allelopathic polyacetylene (cis-dehydromatricaria ester, cis-DME) production of two independent hairy root clones were examined in several culture media and light regimes. cis-DME contents in hairy roots were at the same level as those in normal roots. cis-DME production in root cultures was several-fold lower than that of native plants and greatly repressed by light.