ATP content of cultured callus and hairy root introducted by Ri plasmid of \%Panax ginseng \%C. A. Mey was detected by bioluminescence. The result showed that ATP content in hairy root is obviously higher than that in callus within a growth cycle. The highest ATP content in hairy root is 26.6×10\+\{-12\}mmol/g (fresh weight), while ATP in callus is 2.68×10\+\{-12\}mmol/g (fresh weight). Total saponin content in hairy root reaches 2.486% (dry weight), while the saponin in callus is 1.105% (dry weight). The hairy root inducted by Ri plasmid has vigorous ability in secondary metabolism for ginseng saponin synthesis.
