Fertile transgenic rice plants regenerated from transformed protoplasts

Abstract

THE generation of transgenic plants using gene transfer techniques is important to both the investigation of gene regulation and the genetic engineering of crops¹. The Ti plasmid of Agrobacterium tumefaciens is now routinely used to transform dicotyledonous plants², and the transfer of foreign genes to unorganized tissue^3–6and plants^7,8 has been accomplished using direct DNA transfer methods^9–11. A protocol for the easy and reproducible production of fertile transgenic cereals, however, has not yet been described. We report here the production of fertile transgenic rice plants obtained by introducing the bacterial hph gene, encoding hygromycin B resistance¹² (Hm^r), into protoplasts of Oryza sativa (L.) by electroporation. The non-selectable gene encoding β-glucuronidase was also transferred with the hph gene and its expression was detected in the progeny of the stable transformant.