1Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China; 2School of Mathematics, Physics and Biological Engineering, Inner Mongolia University of Science and Technology, Baotou 014010, Inner Mongolia, China
Abstract：The aim of this work was to optimize the transformation system for potato（Solanum tuberosum L.）variety‘Desiree’and to obtain transgenic potato. Explants derived from potato leaves and stems were used as receptor materials to compare transformation efficiency with different time of pre-culture, Agrobacterium tumefaciens content, duration of infection and the proportion of hormones. The results showed that stem was most suitable for the induction of callus and shoots. Stem explants were pre-cultured for 2 days before infection by A. tumefaciens strain Agl-0（OD600=0.5, 10 min）and selected on MS20 containing 1.0 mg?L-1 zeatin-trans（ZT-t）, the highest transformation efficiency was obtained with 80 % of callus induction and 70 % of differentiation. R1, the gene resistant to potato late blight, was introduced into potato through above improved transformation system. PCR analysis to the kanamycin-resistant transformants revealed that R1 gene was integrated into potato genome. Transfer of R1 gene into potatoes had not any impact on agronomic traits compared to the non-transgenic line（CK）and the most transgenic lines had strong resistance to potato late blight verified by inoculation with isolate 89148-9（0）.
