High-frequency Agrobacterium tumefaciens -mediated transformation can be obtained in canola by optimizing the preconditioning time of the explant and cocultivation time with A. tumefaciens . A preconditioning time of 72 h and cocultivation of 48 h synergistically increase the transformation efficiency to 25%. In addition, the recovery of transgenic plants can be facilitated by overcoming hyperhydration, which increases the rooting frequency to 100%.