Genetic transformation of embryogenic suspension cultures of sweetpotato cv. Lizixiang was conducted by using Agrobacterium tumefaciens strain A208SE harboring the binary vectors pROA93 with β-glucronidase(GUS)and neomycin phosphotransferase(NPTⅡ)genes. The results indicated that embryogenic suspension cultures precultured for 1 - 3 d were suitable for the transformation. The optimal cocultivation time was 4 - 5 d. The optimal concentration of kanamycin was 50-75 mg L-1 for suspension culture and 100 mg L-1 for embryogenic callus proliferation and plant regeneration. The optimal concentration of carbencillin was 100 mg L-1. Transgenic plants identified with GUS assays and PCR analyses were obtained.
ZHAI Hong and LIU Qing-chang(Key Laboratory of Crop Genomics and Genetic Improvement, Ministry of Agriculture/China Agricultural University , Beijing 100094 , P.R. China)