Essential oil from Negramina (Siparuna guianensis) plants controls aphids without impairing survival and predatory abilities of non-target ladybeetles

Plant essential oils are regarded as interesting alternative tools to be integrated into the management of pest insects. However, as they generally consist of mixtures of numerous molecules, the physiological basis for their action is unresolved. Here, we evaluated the effects of essential oil of the Neotropical plant Siparuna guianensis Aubl., commonly known as Negramina, against an important pest insect: the green peach aphid Myzus persicae (Sulzer), and also in two non-target natural enemies: the ladybeetle predators Coleomegilla maculata (DeGeer) and Eriopis connexa (Germar). In addition, we conducted a computational docking analysis for predicting the physical interactions between the two Negramina essential oil major constituents: β-myrcene and 2-undocanone, and the transient receptor potential (TRP) channels as potential binding receptors in the aphid and ladybeetles. As the most important results, Negramina essential oil caused mortality in M. persicae aphids with an LC95 = 1.08 mg/cm2, and also significantly repelled the aphids at concentrations as low as 0.14 mg/cm2. Our computational docking analysis reinforced such selectivity actions as the Negramina essential oil major compounds (i.e., β-myrcene and 2-undocanone) bound to the TRP channels of M. persicae but not to ladybeetle-related TRP channels. Interestingly, the exposure to the Negramina essential oil did not affect the predatory abilities of C. maculata but increased the abilities of E. connexa to prey upon M. persicae. Collectively, our findings provided a physiological basis for the insecticidal and selectivity potential of Negramina essential oil, reinforcing its potential as a tool to be used in integrated pest control programs. [Display omitted] •Siparuna guianensis essential oil showed adequate against Myzus persicae.•Major compounds of this essential oil selectively bound to M. persicae TRP channels.•Individuals of two ladybeetle species survived the exposure to this essential oil.•Essential oil-exposed ladybeetles were not affected in their predatory abilities.•S. guianensis essential oil is a promising tool to control M. persicae infestations. The essential oil extracted from the Neotropical plant Negramina (Siparuna guianensis), potentially targeting the transient receptor potential (TRP) channels, kills and repels the green peach aphid (Myzus persicae) without impairing survival and predatory abilities of two non-target natural enemies, the predatory ladybeetles Coleomegilla ma