Agrobacterium-mediated transformation of cotyledonary explants of Chinese cabbage (Brassica campestris L. ssp pekinensis)

A procedure for producing transgenic Chinese cabbage plants by inoculating cotyledonary explants with Agrobacterium tumefaciens strain EHA101 carrying a binary vector pIG121Hm, which contains kanamycin-resistance and hygromyc in-resistance genes and the GUS reporter gene, is described. Infection was most effective (highest infection frequency) when explants were infected wi th Agrobacterium for 15 min and co-cultivated for 3 days in co-cultivation medium at pH 5.2 supplemented with 10 mg/l acetosyringone. Transgenic plant s of all three cultivars used were obtained with frequencies of 1.6-2.7% wh en the explants were regenerated in shoot regeneration medium solidified wi th 1.6% agar. A histochemical GUS assay and PCR and Southern blot analyses confirmed that transformation had occurred. Genetic analysis of T1 progeny showed that the transgenes were inherited in a Mendelian fashion.