发根农杆菌A4菌株诱导人参（Panax ginseng C.A.Meyer）产生发根，诱导率31.6%。转化发根可在无任何激素的MS培养基上快速生长，且具有分枝性强、丛生、无向地性等特点。通过对液体培养条件的选择，发现人参发根在1/2MS液体培养基上（25℃、110r/min摇床上暗培养）获得最大生长速率，经14 d培养，人参发根鲜重增加了7.97倍。利用高效液相色谱法测定发根中人参皂甙含量发现，发根系R9923中人参单体皂甙Rb1含量达到10.38mg/g，超过栽培六年生人参根中Rb1含量（6.45mg/g）。用高压纸电泳方法在人参发根中检测到农杆碱及甘露碱的存在。Southern点杂交证明：本研究获得的人参发根确已被A4菌株Ri质粒的T-DNA所转化，并被整合到人参发根DNA上。%Hairy roots of ginseng (Panax ginseng C. A. Meyer) were induced by strain A4 of Agrobacterium rhizogenes and the induction rate was 31.6%. The transformed hairy roots grew rapidly on MS medium without phytohormones and were characterized by strongly branching, clustering and non-geotropism, etc. The hairy roots of ginseng achieved the highest growth rate on MS liquid medium (shaked at 110 r/min at 25℃ in darkness) and their fresh weight was increased by 7.97 times after culture for 14 days. Determined by HPLC, the content of ginsenoside-Rb1 in hairy root clone R9923 was found to be 10.38 mg/g, higher than that of 6-year-old cultivated ginseng (6.45mg/g). Agropine and mannopine were detected in the hairy roots of ginseng by the high-voltage paper electrophoresis． Southern dot blotting proved that the hairy roots of ginseng had been indeed transformed by the strain A4 and the T-DNA of Ri plasmid had been integrated into the DNA of hairy roots.
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