[Establishment and analysis of in vitro culture system for transgenic Salvia miltiorrhiza hairy roots].

OBJECTIVE: To establish a culture system for transgenic Salvia miltiorrhiza hairy roots. METHOD: Investigated the success rate of different explants, different infection time and different co-culture time to induce hairy roots of S. miltiorrhiza. Co-cultured explants were sterilizated with 400 g x L(-1) Cef water for 5 min, inoculated on MS solid medium supplied with 400 mg x mL(-1) cef and 2.5 g x L(-1) Hyg, and then transfered to the 67-V liquid medium with 2.5 g x L(-1) Hyg after complete sterilization. GFP fluorescence detection was performed to detect positive hairy root lines. PCR method to detect rolC gene which is the specific gene of hairy root. Biomass was determinated in different growth periods of root lines. HPLC was conducted to measure the content of dihydrotanshinone I of transgenic hairy roots. RESULT: Leaf base of S. miltiorrhiza was used as a perfect explant to Induce hairy roots, the success rate can reach 93.3%. Inducing efficiency was up to 63.3% after Agrobacterium infection for 10 min. Co-culture for 2-3 d can reach the best induced effect. It is a high credibiliy to use PCR method combined with detection of GFP fluorescence to identified positive transformants. There is a close contact between biomass increases and secondary metabolite accumulation of transgenic hairy roots. CONCLUSION: Successfully in vitro culture system has been established in transgenic S. miltiorrhiza, and this research can lay foundations for the further genetic engineering applications.