Methods and materials for conferring pest resistance to plants are provided. Plants are transformed with a silencing construct homologous to a gene of a plant pest that is essential for the survival, development, or pathogenicity of the pest. This results in the plant producing RNAi to the selected gene, which, when ingested by the pest results in silencing of the gene and a subsequent reduction of the pest's ability to harm the plant. In other embodiments, the pest's reduced ability to harm the plant is passed on to pest progeny. Methods and materials for depathogenesis of pests is also provided.