一种加工型马铃薯品种的农杆菌转化体系研究

大西洋马铃薯是经济价值很高的炸片型加工品种，逆境胁迫下，易产生褐变、空心等问题，影响加工品质。为获取抗逆境胁迫的优质转基因新品种，采用根癌农杆菌介导法，以大西洋马铃薯的茎段为外植体，建立了快速，简便，高效的遗传转化体系。从共培养到转化植株获得只需7-8周，转化频率达80%。结果表明茎段是较好的转化受体，硫代硫酸银可以有效促进不定芽分化并提高再生频率。PCR、Southern杂交分析证明外源基因已经成功整合到马铃薯再生植株的基因组中。该转化体系为大量开发转基因马铃薯植株，进而筛选优质的马铃薯炸片加工型新品种奠定基础。

Agrobacterium-mediated Transformation of an Economically Important Potato Cultivar Using Internodal Explants

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.