A plant material comprises a genomic nucleotide sequence encoding a SUSIBA2 or SUSIBA2-like transcription factor under transcriptional control of a promoter active in the plant material. The genomic nucleotide sequence encoding the SUSIBA2 or SUSIBA2-like transcription factor lacks at least a portion of an activation region of a SUSIBA1 or SUSIBA1-like promote represent in an intron of a wild-type version of the genomic nucleotide sequence encoding the SUSIBA2 or SUSIBA2-like transcription factor. The plant material has a controlled production of carbohydrates, in particular starch or starch and fructan. In particular, the plant material can be designed to produce carbohydrates at enhanced levels.