The present invention relates to pesticide preparations and methods based on RNAi technology. The invention discloses target genes (fragments) useful in the control of Lepidoptera insects. Nucleic acid inhibitors or hosts expressing the nucleic acid inhibitors, based on the nucleic acid sequences of these target genes, can effectively kill Lepidoptera insects. The invention also discloses applications using the nucleic acid inhibitors or hosts expressing the nucleic acid inhibitors.
