Toxicity, Deterrent and Repellent Activities of Four Essential Oils on (Hemiptera: Aphididae).

Chemical insecticides have many harmful effects, including as foodborne residues and environmental contaminants, as well as side effects on natural enemies and serious risks for human health. The use of plant-derived essential oils (EOs) as effective bio-agents has become an essential component of integrated pest management. In this study, the contact toxicity, deterrent, and repellent activities were evaluated for essential oils obtained from , and , grown at high altitudes in the Taif region, KSA, on . Furthermore, the toxicity of these EOs against the predator was estimated. A total of 17, 14, 16, and 26 compounds were identified in the EOs of , , , and , respectively. They showed a variation in the major compounds: (Carvone, 61.16%), (Pulegone, 48.6%), (Eucalyptol, 33.52%), and (α-pinene, 36.65%). A contact toxicity test on imago and larvae showed that LC were approximately four-fold greater for all tested EOs towards aphids compared to towards the predator, while the two species of sp. were more effective than the other two species of sp. The LC values on ranged from 1.57 to 2.97 µg/mL, while on larvae, they ranged from 5.96 to 10.33 µg/mL. Furthermore, the EOs of two species of sp. showed excellent repellence and deterrence against . In conclusion, the tested EOs, especially those from sp., have been shown to be promising natural aphicides, repellent, and deterrent against , and they are safe for important insect predators.