This invention relates to methods for knock-down of a target gene in plants, particularly efficient and specific methods for knock-down of a target gene in plants. This invention also relates to methods for silencing endogenous plant genes or plant pathogen genes. It further relates to nucleic acid constructs (DNA, RNA) which comprise a nucleic acid sequence that corresponds to a target gene or fragment thereof flanked by two complementary sites to an smRNA, e.g., a miRNA (one complementary site is on either side of the nucleic acid sequence), resulting in, for example the configuration: complementary site--nucleic acid sequence that corresponds to a target gene--complementary site.