Expression patterns and functional analysis of the short neuropeptide F and NPF receptor genes in Rhopalosiphum padi

Abstract The short neuropeptide F ( sNPF ) and NPF receptor ( NPFR ) genes play important roles in many physiological processes. However, information on the survival‐related functions of sNPF and NPFR under different stress conditions is lacking in aphids. In this study, we cloned sNPF and NPFR , and investigated the expression levels of these genes in different developmental stages, wing morphs, and stress conditions of the bird cherry‐oat aphid ( Rhopalosiphum padi L.), an important agricultural pest. The sNPF and NPFR transcript levels varied among developmental stages, and their expression levels in alate females were significantly higher than those in apterous females. In addition, starvation resulted in significantly increased s NPF expression, which then recovered after refeeding. Heat stress and insecticides significantly affected transcription of both genes. sNPF and NPFR knockdown in R. padi using RNA interference revealed optimal interference efficiency at 48 h post‐injection. sNPF knockdown significantly decreased adult longevity, 15‐d fecundity, and food intake. Additionally, mortality under starvation, insecticides, and heat stress conditions was significantly higher after injection with double‐stranded sNPF in R. padi . NPFR knockdown significantly affected food intake and starvation resistance in R. padi . These results strongly indicate that sNPF plays vital roles in food intake, longevity, and reproduction in R. padi , and it can significantly affect the pest's response to stress conditions.