Abstract: Abstract: The choline dehydrogenase（CDH）gene and the betaine aldehyde dehydrogenase（BADH）gene are the key genes of the glycine betaine’s synthesis pathway. They were cloned into the vector pCAMBIA2300-35s-OCS.They were tandem and have their respective promoters and terminators. The vector pCAMBIA2300-betA-BADH was transformed into the Agrobactrium tumefaciens GV3101, LBA4404 and will be used in the genetic transformation of the dicotyledons.