Ri T-DNA对盾叶薯蓣的遗传转化及薯蓣皂甙元产生的影响

利用农杆菌介导法成功地将Pd T-DNA转入药用植物盾叶薯蓣，产生了毛状根，经分子信标探针检测农杆菌Pd质粒上的T-DNA已整合进植物基因组中。研究建立了毛状根大量快速繁殖技术，基本技术要求为：1／2 MS液体培养基，28℃培养温度，350lux弱光条件下有利于毛状根的增殖培养，提高生物量。HPLC测定结果显示，转基因获得的毛状根其薯蓣皂甙元的含量分别是微块茎、愈伤组织和植物体合成量的5．68倍、6．12倍和2．68倍。

Genetic Transformation Mediated by Ri T-DNA and the Accumulation of Diosgenin of Dioscrea zigiberensis G. H. Wright

This paper reported the technique which was used to induce hairy roots in Dioscrea zigiberensis G.H.Wright.Diverse microcuttings were inoculated with strains of A.rhizogenes in different media.Hairy roots were efficiently induced from micro-tubers by infection with A.rhizogenes strain A 4 and R1601,which exhibited the transformation frequency of 78% and 81% respectively.When sub-cultivated in hormone free MS liquid medium,the root clones grew rapidly and reached stationary phase after 30 d. Real-time PCR analysis indicated that Ri plasmid T-DNA integrated into the genome of transformed roots.HPLC analysis of extracts of hairy roots,micro-tubers,calli and plantlets showed that the content of diosgenin was 8.20,1.44,1.34 and 3.06 mg/g DW,respectively.The diosgenin content significantly increased in hairy roots.Hairy-root appears to be an effective means for commercial application to produce diosgenin from in vitro cell culture.