Plant Molecular Biology Reporter 19: 55-64, March 2001 9 2001 International Society for Plant Molecular Biology. Printed in Canada. Protocols Transformation of Brazilian Elite Indica-Type Rice (Oryza Sativa L.) by Electroporation of Shoot Apex Explants VANIA L. MUNIZ de PADUA 1'*, RODRIGO P. FERREIRA 1, LARISSA MENESES l, NATHALY UCHOA 1, MARCIA MARGIS-PINHEIRO 1 and ELISABETH MANSUR 2 1UFRJ, lnstituto de Biologia, Dept. Genetica, Cidade Universitdtria - CP68011, CEP 21944-970 - Rio de Janeiro, RJ - Brazil; 2UERJ, Instituto de Biologia, DBCG - Rua Sdo Francisco Xavier 524 - PHLC/sl 505 - Rio de Janeiro, RJ - Brazil Abstract. We have generated transgenic plants of a Brazilian elite Indica-type rice by electroporation of shoot apices. This approach avoids a callus phase and produces 0.4-13.8% resistant plants. Transgenic plantlets were transferred to soil a few weeks after explant electroporation. Root segments from plantlets obtained from transformation exper- iments with pAHC25 plasmid were GUS positive. Integration of the introduced gene into the genome was demonstrated by PPT and antibiotic screening as well as by PCR and Southern blot hybridization of genomic DNA isolated from R 2 plantlets. Key words: direct regeneration, direct transformation, HYG, NPT, PPT Abbreviations: ASPm, ASP modified electroporation buffer; G418, geneticin; Hyg, hygromycin; PPT, phosphinotricin. Introduction Recent applications of tissue culture and molecular biology techniques have led to rapid genetic improvements of rice. Both Indica and Japonica transgenic rice plants have been obtained through biolistic methods (Tang et al., 1999; Kohli et al., 1999) and Agrobaterium tumefaciens-based systems (Takakura et al., 2000; Yin and Wang, 2000). An alternative approach is direct gene transfer through electroporation of protoplasts (Lin et al., 1997; Rao et al., 1995) or intact cells and tissues (D'Halluin et al., 1992; Arencibia et al., 1997). Electroporation of tis- sues has been used for transient (H~insch et al., 1996; Seki and Morikawa, 1999) *Author for correspondence. Present address: UFRJ, Instituto de Ci~ncias Biom6dicas, Departamento de Bioquimica M6dica, Cidade Universitdria - CP68011, CEP 21941-590 - Rio de Janeiro, RJ - Brazil; e-mail: vanpadua@bioqmed.ufrj.br; fax: 55-21-2708647; ph: 55-21-270-2130 or 55-21-290-5229.