Transgenic Lines of Oryza Sativa (Basmati 2000) Expressing Xa21 Demonstrate Enhanced Resistance to Bacterial Blight

An efficient transformation system for rice was established by co-cultivating calli, derived from 21-day-old scutellum, with Agrobacterium tumefaciens cells (OD600 = 0.04), maintained on filter paper, moistened with 4 mL of a medium, and supplemented with 400 mu M acetosyringone, for a period of 2 days. Presence of the transgene was confirmed by polymerase chain reaction, and stable integration and copy number of the transgene were determined by Southern blot analysis. Among seven plants analyzed, six possessed single T-DNA integration events, while one plant was found to have two integrated copies of the T-DNA. A total of 45 T-0 plants were grown in the greenhouse to obtain the T-1 generation. T-1 plants evaluated for presence of the transgene and for response to inoculation with the bacterial leaf blight pathogen, Xanthomonas oryzae pv. Oryzae, exhibited Mendelian segregation (3:1) for the transgene as well as enhanced resistance to bacterial blight.