The binary vector method for plant transformationation1 takes advantage of Agrobacterium tumefaciens and its capacity to transfer T-DNA to plant cells. In this method, the pathogenic genes of Agrobacterium tumefaciens T-DNA in the Ti plasmid are replaced with selective marker genes as well as the exogenous target gene. This results in stable integration of the exogenous target gene into plant chromosomal DNA by means of Agrobacterium-mediated transformation. Agrobacterium tumefaciens strain LBA4404 and the binary vector method were invented by Dr. P.J. Hooykaas at Leiden University in the Netherlands. The LBA4044 strain of Agrobacterium tumefaciens contains the pAL4404 plasmid, which includes only the T-DNA vir region and enables only vir gene induction and T-DNA transfer. Agrobacterium tumefaciens Electrocompetent Cells LBA4044 are a widely used bacterial strain for T-DNA transfer to plant cells.