The invention relates to the technical field of
pest control, and discloses dsRNA based on a prodenia litura Ter94
gene as well as a preparation method and application of the dsRNA. The preparation method comprises the following steps: firstly, obtaining a full-length sequence of the prodenia litura Ter94
gene, designing a dsRNA primer based on the sequence, and further synthesizing the dsRNA of the prodenia litura Ter94
gene based on the primer. The dsRNA of the Ter94 gene obtained by the invention can cause the total death rate of prodenia litura larvae on the fifth day to be 26.67%; dsRNA of the Ter94 gene is wrapped with
chitosan to form nano-particles, the nano-particles are applied to 3-
instar larvae through epidermal
permeation, and the death rate of the prodenia litura larvae is increased to 36.67% after 5 days; after the dsRNA nano-particles and
emamectin benzoate with the sublethal concentration of 5 mg / L or
emamectin benzoate with the sublethal concentration of 5 mg / L jointly act, the death rates of larvae are increased to 90% and 83.33% respectively.