A High-Efficiency Agrobacterium-Mediated Transformation System of Rice (Oryza sativa L.)

Agrobacterium -mediated transformation of rice has been routinely performed according to the protocol reported by Hiei et al. (Plant J. 6:271–282, 1994). However, several elite japonica and many indica varieties cannot be efficiently transformed by Agrobacterium system. Also a large number of transformants are required to generate T-DNA insertion and FOX libraries as well as gene-targeting studies. To overcome these challenges, we established a high-efficiency transformation system in rice by cocultivating rice calli with Agrobacterium on filter papers moistened with enriched liquid media instead of using solid media (Ozawa, Plant Sci. 176:522–527, 2009; Ozawa and Takaiwa, Plant Sci. 179:333–337, 2010). In this system, the transformation efficiency of the calli is almost 100% in many varieties.