Abstract: This paper reports the establishment of an efficient transformation system for Tax us brevi,folia, using Agrobacterium rhizogenes A4(ATCC31798). Hairy roots are induced from shoot explants after 30- 35 d inoculation with the bacteria. Frequency of the explants transformation by A4 is 30% after 40 d. Transformation is confirmed by agropine monoclonal antibody ELISA ana-lysis. The average value of biomass of hairy root cultures suspended in hormone free B5 medium increases 8.67 times after 20 d culture. It is 2.9 times as much as callus cu1ture from T.brevifhlia in the same culture condition. The hairy root culture can synthesize taxol whose content is l.3- 8 times as much as that in the callus from T. brevifolia. Taxol can also be detected in growth me-dium.

Key words: Taxus brevifolia