Transgenic Plant Production from Embryogenic Callus of Sweet Potato (Ipomoea batatas (L.) Lam.) Using Agrobacterium tumefaciens

Abstract

Transformed sweet potato plants were obtained from embryogenic calli following Agrobacterium tumefaciens-mediated transformation. A. tumefaciens strain EHA101/pIG121-Hm used in the present study contained a binary vector with genes for β-glucuronidase (gusA) and hygromycin resistance (hpt). Around ten hygromycin resistant cell clusters were produced from 1g fresh weight of the infected embryogenic calli. The hygromycin resistant plantlets were regenerated from 53.1% of the hygromycin-resistant calli. Histochemical GUS assay and Southern hybridization analysis indicated that these plants were stably transformed with a copy number of introduced genes of one to three. Transgenic plants grew normally and formed storage roots after 3 months of cultivation in a green house.