Agrobacterium-mediated Transformation of an Economically Important Potato Cultivar Using Internodal Explants
一种加工型马铃薯品种的农杆菌转化体系研究

Potato cultivar Atlantic is widely grown for potato chips in the world. However, this economically important potato cultivar exhibits very poor yields and traits under severe environmental stress. To develop an efficient plant transformation system that could be used to produce large scale transgenic potato plants with enhanced tolerance to environmental stress and therefore would be beneficial for potato processing industry, Agrobacterium-mediated transformation of internodal stem explants using both superoxide dismutase (SOD) and ascorbate peroxidase (APX) genes under the control of an oxidative stress-inducible SWPA2 promoter was performed. Comparing to leaf explants, stem internodal explants were less liable to damage during manipulation, more amenable to in vitro conditions. The addition of silver thiosulfate to the selection medium considerably promoted the shoot induction from explant-derived callus. Seven to nine shoots per stem explant were obtained. By combining the best treatments, this system yielded shoot induction frequency of 94.2% and transformation frequency of 80% of internodal stem explants. Stable integration of the transgenes was confirmed by PCR and Southern blot analyses. In conclusion, short duration (7~8 weeks), high efficiency and easy process make this system well suited for wider commercial applications of transgenic Atlantic potato plants.