The present invention concerns a method of genetic modification of a TGB-3 wild type viral sequence for reducing or suppressing the possible deleterious effects of the agronomic properties of a transformed plant or plant cell by said TGB-3 viral sequence. The invention further relates to genetically modified TGB-3 viral sequences suitable to induce gene silencing. In particular hairpin constructs based on such sequences proved highly efficient to induce a PTGS mechanism and degradation of the whole of RNA2 thereby. When plants are transformed accordingly the spread of the virus in the plant is significantly reduced or blocked.