CELLULAR & MOLECULAR BIOLOGY LETTERS Volume 9, (2004) pp 287 – 300 http://www.cmbl.org.pl Received 4 November 2003 Accepted 15 March 2004 * Corresponding author, E-mail: mike.davey@nottingham.ac.uk Abbreviations used; cv. – cultivar; DIG – dioxigenin; GUS - ß–glucuronidase; gus - ß– glucuronidase gene; hpt - hygromycin phosphotransferase gene; MUG - 4– methylumbelliferone glucuronide; nptII - neomycin phosphotransferase II gene; MS - Murashige and Skoog [12]; MSS - mature seed scutellum; X-Gluc - 5-bromo-4-chloro-3- indolyl ß-D-glucuronide. Agrobacterium-MEDIATED TRANSFORMATION OF BANGLADESHI INDICA RICES MOHAMMAD AL-FORKAN 1 , J. BRIAN POWER 1 , PAUL ANTHONY 1 , KENNETH C. LOWE 2 and MICHAEL R. DAVEY 1 * 1 Plant Sciences Division, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK, 2 School of Biology, University of Nottingham, University Park, Nottingham NG7 2RD, UK Abstract: Morphologically normal, fertile transgenic plants were obtained by co-culturing embryogenic calli of the Bangladeshi Indica rice cultivars BR26 and Binni with Agrobacterium tumefaciens strain LBA4404 carrying the super binary vector pTOK233. Acetosyringone (100 μM) in the medium during co- culture (25-28ºC) and selection on hygromycin B (50 mg l -1 ) were essential for efficient transformation. Stable integration and expression of ß-glucuronidase, neomycin phosphotransferase and hygromycin phosphotransferase genes in regenerated plants were confirmed by histochemical and fluorometric assays, ELISA and Southern analysis. Two to 3 copies of T-DNA were integrated into regenerated plants; transgene expression did not correlate with gene copy number. Mendelian segregation of transgenes occurred in T1 seed progeny. Key Words: Agrobacterium-Mediated Transformation, Oryza sativa L., Transgene Integration and Expression, Transgenic Indica Rice INTRODUCTION Rice (Oryza sativa L.) provides the staple diet of more than one third of the world’s population, with Indica rice feeding more than two billion people, predominantly in developing countries [1]. Rice improvement by conventional approaches is limited by natural incompatibilities, even between related species, and by the time-scale of delivery of exploitable germplasms from most breeding