The main component of the aphid alarm pheromone ()-β-farnesene affects the growth and development of by mediating juvenile hormone-related genes.

The ()-β-farnesene (EβF) is one of the most important secondary metabolites in some plants and provides indirect defense against aphids. However, the direct effect of EβF against pests is still unclear. In this study, various concentrations of EβF (0.16, 0.8, and 4 g/kg) were provided in an artificial diet to determine the direct effects of EβF on . The results showed that an artificial diet containing 4 g/kg of EβF reduced the final survival of the larvae and per female fecundity of adults significantly when compared with CK and SC controls ( < 0.05), then ultimately it also significantly affected the intrinsic rate of increase ( < 0.05). Furthermore, the results of the EβF bioassay in an artificial diet also indicated that the proliferation of the population was inhibited by the ingestion of EβF in a dose-dependent manner. Combined differential RNA-seq data and RT-qPCR analysis, it was found that four key genes involved in juvenile hormone degradation significantly upregulated in larvae treated by EβF at a dose of 0.8 and 4 g/kg when compared with two controls ( < 0.05). This indicated that EβF could disturb the normal function of juvenile hormones and reduce the survival rate of larvae. Additionally, two key genes that regulate per fecundity of females, including and , were significantly downregulated in adult females ( < 0.05) when they were treated with 0.8 and 4 g/kg of EβF at the larval stage, relative to the expression of these genes after treatment with controls. These findings suggested that EβF first disturbed the normal function of juvenile hormone by upregulating key degradation genes, and then inhibited the expression of / genes and proteins, thus reducing the population size of by increasing larval mortality and inhibiting per female fecundity.