A stable transformation system for the ornamental plant, Datura meteloides DC

A transformation system is described for Datura meteloides using the supervirulent Agrobacterium tumefaciens strain 1065, carrying both the beta-glucuronidase (gusA) and neomycin phosphotransferase II (nptII) genes between the T-DNA border sequences of the binary vector. The importance of conditions such as the preculture period of the plant tissues, wounding, bacterial dilution and incubation time were evaluated in terms of transgenic plant production. A preculture period of 2-3 days, using a 1 : 20 or 1 : 10 (vol:vol) dilution of an overnight bacterial culture, resulted in optimum shoot regeneration, with 48% from a total of 576 explants regenerating transformed shoots. Expression of the gusA and nptII genes was confirmed by a GUS fluorometric assay and by NPTII ELISA. Southern analysis revealed the integration of both transgenes, which segregated as dominant Mendelian traits in seed progeny.