A method selected from the group consisting of manipulating fructan biosynthesis in photosynthetic cells of a plant, enhancing biomass in a plant, and selecting for transformed plants, said method including introducing into said plant an effective amount of a genetic construct including a light-regulated promoter, or a functionally active fragment or variant thereof, operatively linked to nucleic acids encoding one or more fructan biosynthetic enzymes, or functionally active fragments or variants thereof, and wherein when said method is selecting for transformed plants said method further includes selecting plants with enhanced biomass. Wherein said one or more fructan biosynthetic enzymes are selected from the group consisting of 1-SST, 1-FFT, 6-SFT and 6G-FFT.
