| Object: Taraxacum kok-saghyz Rodin, composite dandelion, is a perennial herb, also called Russiadandelion, together with Brazil hevea and Parthenium called the three produce rubber plants. Its root andleaf have rubber organization, of which the structure and function are similar to Brazil hevea, the roots ofperennial plants contain up to20%rubber, it is a rubber production plant which has good developmentprospects, and also can be used to study the mechanism of rubber production glue as a model plant, so ithas a huge research prospect. This research used the kok-saphy plants collected from wild, though the planttissue culture technology to set up the high frequency regeneration system of kok-saphy. Based on it, westudied the agrobacterium-mediated genetic transformation research.Methods: The effects of disinfection time and exogenous hormones on the survival rate, induction ofregeneration bud, elongation and root formation were studied by taking young leaf of Taraxacumkok-saghyz as explants. We discussed the kanamycin’s effect on the induction of resistance kok-saphyz budsand rooting, studied the inhibition of carboxy benzylpenicillin and amphotericin cephalosporin onagrobacterium. On the basis of that, we determined the appropriate type and concentration of antibiotics ingenetic transformation. Through the agrobacterium-mediated method, we transferred GUS gene intokok-saphy. In genetic transformation, we pre-cultured the explants for48h, infected them in the MSsuspension of agrobacterium which added200mg/L AS for30min, then co-cultured for48h, at last weproceeded antibiotics screening。Results: The results showed that the optimum disinfection method was treated with0.1%HgCl2for7min;the optimum regeneration medium was MS+1.5mg/L6-BA+0.1mg/L NAA, and the average induction ratewas97.3%; the optimum shoot regeneration medium was MS+2.0mg/L6-BA+0.02mg/L NAA+0.4mg/LGA3; the best rooting medium was1/2MS+0.2mg/L NAA, of which the rooting rate was100%. The tissuecultured plants obtained grew well and had high survival rate after transplanting, finally we established theoptimum regeneration system of Taraxacum kok-saghyz.50mg/L Kan had a very good screening effect tothe resistance buds of kok-saphyz, in rooting screening research, the appropriate concentration of Kan was35mg/L. The best antibacterial antibiotics was cb, of which the appropriate concentration was500mg/L.We achieved35resistant test-tube plantlets, then proceeded GUS staining and molecular biologicaldetection, finally got6transgenic plants, the transformation rate was17.4%.Conclusion: This study established the high frequency regeneration system of kok-saphy, proceeded theagrobacterium-mediated genetic transformation, achieved transgenic kok-saphy plants, laid the foundationfor genetic transformation research of kok-saphy in the future. |
