Fuente: WIPO "tomato" New peptides (cPEPs) having a size from 4 to 70 amino acid residues and a method for preparing the cPEPs. Also, a method for modulating the accumulation of specific proteins in plant cells by introducing the cPEPs into the plant cells. The cPEPs may be introduced to either promote the development of a plant or slow down or prevent the development of a plant.