The present invention relates to transgenic plants resistant to parasites that their normal life cycle includes feeding on the plant cytoplasm, including insects, nematodes and fungi, wherein the plants are engineered to produce small interfering RNAs (siRNAs) capable of silencing a parasite specific gene. Particularly the parasite gene is a stage-specific gene, more particularly a gene involved in essential, early developmental stages of the parasite in or on the plant.