Acaricidal Activity of Palm Oil on Aceria guerreronis (Acari: Eriophyidae) and a Nontarget Predator

The coconut mite. Aceria guerreronis Keifer (Acari: Eriophyidae), is a severe and ubiquitous pest of coconut plantations worldwide. Vegetable oils contain fatty acids that are active against a variety of agricultural pests; however, little is known about their efficiency in controlling A. guerreronis as well as their adverse effects on its natural enemies. Here, we assessed the chemical profile of palm oil as well as its toxicity and repellence to both A. guerreronis and Typhlodromus ornatus Denmark and Muma (Acari: Phytoseiidae), a natural enemy of the pest. Oleic, palmitic, and linoleic acids accounted for over 85% of palm oil fatty acid composition. Also, palm oil was approximately 4-fold more toxic to the coconut mite than to its predator. Furthermore, the lethal concentration percentage (LO)50 and LC99 of palm oil indicated greater activity against the coconut mite than to its predator. Therefore, by exhibiting higher toxicity and repellence to the coconut mite, with substantial selectivity to the predator T. ornatus, palm oil is a promising tool to be integrated in the control of A. guerreronis in coconut plantations.