Abstract: The invention relates to a method for interfering with processes in the male meiocytes of a plant, by combining a first plant which may comprise a rootstock, which transgenically harbours a nucleic acid sequence, with a scion from a second plant grafted onto the rootstock of the said first plant, whereby the said transgenic nucleic acid sequence generates polynucleotide molecules in the rootstock of the first plant, which polynucleotide molecules are transported systemically across the graft junction to enter the male meiocytes produced by the scion of the second plant, and wherein the said systemically transported polynucleotide molecules are at least partially complementary to a transcript expressed in the male meiocytes produced by the scion of the second plant.