A process of producing a transgenic multi-cellular plants or parts thereof expressing a trait of interest, said trait having a controlled distribution of said trait to progeny, wherein said process comprises (i) producing a first plant or a cell thereof having in a first locus of a nuclear chromosome a first heterologous nucleotide sequence comprising a first fragment of a nucleotide sequence encoding said trait of interest, (ii) producing a second plant or a cell thereof having in a second locus of a nuclear chromosome homologous to said nuclear chromosome of step (i), a second heterologous nucleotide sequence comprising a second fragment of the nucleotide sequence encoding said trait of interest, and (iii) hybridising said first and said second plant or cells thereof to generate progeny exhibiting said functional trait of interest due to binding between a protein or polypeptide encoded by said first heterologous nucleotide sequence and a protein or polypeptide encoded by said second heterologous nucleotide sequence. Further, the invention provides a process of producing hybrid seeds for agriculture.