Genetic constructs capable of manipulating fructan biosynthesis in photosynthetic cells of a plant, said genetic constructs include a promoter operatively linked to a nucleic acid encoding a bacterial FT enzyme. These constructs can be used in modification of fructan biosynthesis in plants and, more particularly, for manipulating fructan biosynthesis in photosynthetic cells. The constructs can also be used for increasing plant biomass and, more particularly, for enhancing biomass yield and/or yield stability, including shoot and/or root growth in a plant, and for enhancing the productivity of biochemical pathways.
