The present invention is directed to nucleic acid sequences coding for a protein which, (1) under a respective promoter, is able to suppress or repress or delay flowering of a plant, and (2) includes the motive “NAPDIIDS” (SEQ ID NO: 10) or, in preferred cases, “VNAPDIIDS” SEQ ID NO: 67), with the exception of the nucleic acid of the gene StSP5G or a part thereof. Preferably, the nucleic acid sequence belongs phylogenetically to the FT-clade of the PEBP gene family, wherein the motive “(V)NAPDIIDS” (SEQ ID NO: 68) is in place of the “(V)YAPGW” motive (SEQ ID NO: 69) of the flowering promoting proteins AtFT and BvFT2.The invention is further directed to peptides or proteins, obtainable by expression of the nucleic acid of any of the preceding claims, vectors, comprising a nucleic acid sequence as defined above, and to plants, parts of plants, or seed of plants, the plants comprising such a nucleic acid sequence.