THE IMPACT OF SELECTION PARAMETERS ON THE PHENOTYPE AND GENOTYPE OF TRANSGENIC RICE CALLUS AND PLANTS

Transgenic rice embryogenic callus and plants were recovered from experiments involving electric discharge particle acceleration (Accell(TM) technology). Critical parameters influencing successful delivery and stable integration of exogenous DNA into organized rice tissue had been identified previously. We report here on the effects of one selective agent (hygromycin B) on the phenotype and genotype of recovered callus and plants. The nature, timing and culture practices appeared to be more critical for the successful recovery of transgenic callus and plants than the level of selection used. By utilizing the procedures described in this report, transformation frequencies well in excess of 10% were obtained routinely in all varieties of rice tested. The combination of Accell(TM) technology with a selectable and prolific regeneration culture system resulted in the development of a variety-independent and highly efficient method for the routine introduction of any gene into any rice variety.