Agrobacterium rhizogenes-mediated transformation of Gentiana utriculosa L. and xanthones decussatin-1-O-primeveroside and decussatin accumulation in hairy roots and somatic embryo-derived transgenic plants

•Accumulation of xanthones in transformed Gentiana utriculosa was investigated.•Hairy root cultures of G. utriculosa were established using A4M70GUS strain.•Hairy roots of line 9 produced 4.5-fold more decussatin than plants from nature.•Transgenic line 9 could be considered for large scale production of xanthones.