An efficient transformation system for the Australian rice cultivar, Jarrah

A rapid and efficient transformation system for the generation of large numbers of transformed, fertile, transgenic rice (Oryza sativa L.) plants of the Australian rice cultivar, Jarrah, is described. Embryogenic callus pieces derived from mature seeds were bombarded with gold particles coated with DNA. Two plasmids were used, one containing a gene encoding hygromycin phosphotransferase (hph, conferring hygromycin resistance) as a selectable marker and the other containing uidA (gus) as a reporter gene. The calli were selected for their resistance to hygromycin. DNA uptake, integration and expression of the hph and gus gene in selected rice were investigated by various PCR methods and dot blot and Southern analysis of genomic DNA extracted from transformed rice plants. On average one independently transformed hygromycin resistant plant was recovered from every 2.4 pieces of callus bombarded. Selection with Biolaphos using the Bar gene as selectable marker was not successful in this system.