Transformation of soybean by infecting embryonic calli with Agrobacterium tumefaciens and that of soybean and kidney bean by injecting the bacteria into germinating seeds

An effort was made to generate transgenic plants from embryogenic callus of soybean (Glycine max (L.) Merrill) by using Agrobacterium tumefaciens, strain EHA101 harbouring the binary vector pIG121, which contains neomycin phosphotransferase (NPTII), hygromycin phosphotransferase (HPT) and β-glucuronidase (GUS) genes. Analysis by PCR and Southern blotting analysis of the putative transgenic soybean showed that the plants carried the genes for GUS, NPTII and HPT. The germinating seeds were injected with Agrobacterium tumefaciens, followed by sonication and vacuum infiltration. Analysis of the progeny plants by PCR and Southern hybridization showed that the transformed plants maintained the transferred DNA. Compared with transformation of embryogenic callus, that of germinating seeds was simple and repeatable, since it required no prior tissue culture steps and produced transgenic plants more efficiently. Transgenic plants of kidney bean (Phaseolus vulgaris L.) were also obtained by injection with the Agrobacterium into germinating seeds.