Agrobacterium-mediated high frequency transformation in dwarf recalcitrant rice cultivars

Abstract

The Agrobacterium-mediated transformation was done in rice (Oryza sativa L. var. indica) cv. HKR126 and elite cross-bred cv. Pusa Basmati1 (PB1), using strain LBA4404 containing pCAMBIA1300 cloned with gene cassettes; potato proteinase inhibitor and Bacillus thuringiensis endotoxin (plasmid JDW53) or mannitol-1-phosphate dehydrogenase (plasmid RKJ108). Co-cultivation with scutellar-calli derived from mature seeds showed stable and highly efficient transformation. In cvs. HKR126 and PB1, 35% and 41% of hygromycin resistant calli were obtained. The transformation efficiency in PB1 (22.0%) was much higher than in HKR126 (12.5%). Similarly, PB1 had higher plant regeneration efficiency than HKR126. The shoots regenerated per callus were, 3-4 in HKR126 and 5-6 in PB1. The transformation efficiency with pRKJ108 (18.6%) was higher than pJDW53 (15.9%). Polymerase chain reaction (PCR) analysis showed the presence of transgenes in regenerated transgenic plants of both cultivars. © 2007 Institute of Experimental Botany, ASCR.