Apical meristems of buckwheat (Fagopyrum esculentum var. Shinano No. 1) seedlings were transformed by inoculation with Agrobacterium tumefaciens harboring a binary vector containing cDNA of a rice MADS box gene (accession No. (DDBJ) AB003325) in either a sense or an antisense orientation downstream of CaMV35S promoter, The plants transformed (T0) with the cDNA in both orientations showed unique features; the plants transformed with the cDNA in a sense orientation were stimulated in branching, producing many branches, while the plants transformed with the cDNA in antisense orientation were inhibited in both branching and growth. The progenies (T1 plants) of both transformed plants inherited the nature of the respective T0 plant. The analyses using the Southern blot hybridization and PCR revealed that a single copy of the cDNA was integrated in the genomes of T1 plants in sense and antisense orientations, respectively.