Abstract: For the purpose of expression in plant an antigen of Brucella, the causative agent for zoonosis brucellosis, transgenic alfalfa was constructed using agrobacterium mediated gene transfer. Towards that end, a fusion gene rOmp31_48-74-BLS containing Brucella Omp31 antigenic epitope spanning amino acids 48-74 and the lumazine synthase was cloned into vector pJG045 with ligation-independent cloning (LIC). The recombinant vector was transformed into Agrobacterium AGL0 by tri-parental hybrid method, which was used to infect calli of alfalfa Medicago sativa Zhongmu No.1. The transformed calli were identified by PCR, after stimulating the growth of roots, transgenic alfalfa was obtained. The experiment has laid experimental basis for the development of Brucella transgenic plants vaccine in the future.

Key words: Brucella rOmp31_48-74-BLS, Medicago sativa Zhongmu No.1, transgenic plant vaccine