Pest infestations devastate crop production, but chemical pesticides pose environmental and health risks. Eco-friendly biopesticides offer a solution, though limited by bioactive compound discovery. Here, we demonstrate that utilization of Yunnan’s Xishuangbanna—a cucumber diversity hotspot—to identify the local variety XSBN032, which retains desirable agronomic traits under aphid pressure. Metabolomic and GC–MS analyses identify farnesal—a volatile compound significantly enriched in XSBN032—under infested and non-infested conditions. Applying 0.33 g/L farnesal nanoemulsion to cucumber leaves rapidly disrupts aphid metabolism (within 6 h), impairing amino acid pathways and suppressing growth/reproduction, achieving 74.9% mortality within 24 h while preserving plant photosynthesis. Significantly, this treatment demonstrates high environmental safety: 0% earthworm mortality (500 mg/L, 7 days) and negligible effects on natural enemies (0% ladybird mortality; 7.41% green lacewing mortality). Our study establishes an integrated pipeline—from resistant germplasm discovery to biopesticide development—providing a sustainable pest control strategy. Leveraging multi-omics screening and smart delivery systems holds promise for future eco-efficient biopesticides. Here the authors show that a sustainable biopesticide can be developed from chemicals produced by a wild cucumber variety. The farnesal nanoemulsion kills 75% of aphids in 24 h while posing minimal risk to the environment and beneficial insects.
Suo et al. (Fri,) studied this question.