Construction of Expression Vector pCAAFP66 and Its Transformation into Soybean by Agrobacterium-mediated Method

Plant expression vector pCAAFP66(9868 bp),which contained the target gene afp and the screening marker Bar gene,was constructed for soybean transformation.The anti-freezing gene afp was transformed into embryonic tip and cotyledonary node of soybean using Agrobacterium-mediated method and PPT as selective agent.Identification indicated the afp gene was successfully transformed into Huachun 3 and Huachun 6 through the embryonic tip transformation system,with transformation rates 7.4% and 4.0%,respectively.Whereas in the cotyledonary node system no transformed plants was obtained.Analysis of the embryonic tip and cotyledonary node approach revealed that significant differences existed in the regeneration and transformation rate between two genotypes;even with the same genotype,different explants materials had totally different transformation rates.