Submitted to: Insects
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/25/2023
Publication Date: 3/30/2023
Citation: Sutanto, K., Husain, M., Rasool, K., Mankin, R.W., Omer, A., Aldawood, A. 2023. Acoustic comparisons of red palm weevil (Rhynchophorus ferrugineus) mortality in naturally infested date palms after injection with entomopathogenic fungi or nematodes, aluminum phosphide fumigations,or insecticidal spray. Insects. 14(4):339. https://doi.org/10.3390/insects14040339.
DOI: https://doi.org/10.3390/insects14040339

Interpretive Summary: Red palm weevil is an important, internally pest of palms in the subtropics worldwide. Acoustic detection is a useful tool to detect its hidden infestations early, enabling better protection of food and ornamental crops. Students and scientists at King Saud University, Riyadh used methods developed by scientists at the USDA-ARS Center for Medical, Agricultural, and Veterinary Entomology, Gainesville, FL, to monitor red palm weevil activity in palm trees. The fungus and nematode treatments, as well as phosphine and emamectin benzoate treatments, decreased red palm weevil acoustic activity to zero over a 2-3-month period, indicating total mortality. The study confirms that acoustic monitoring not only enables detection of hidden infestations but also can reliably assess the time course of treatments that result in mortality and effective treatment in field environments.

Technical Abstract: Red palm weevil (RPW) management is important to the economic success of date palm agri-culture. In this study, entomopathogenic fungi (Beauveria bassiana and Metarhizium anisopliae); entomopathogenic nematodes (Steinernema carpocapsae); aluminum phosphide; emamectin benzoate; fipronil; and a control (distilled water) were evaluated as management tools by monitoring RPW activity after treatment using acoustic sensors. The mean rates of RPW impulse bursts over time after treatment were used as indicators of RPW mortality. Treatments were evaluated over a 6-month period after initiation of treatments. Fungi, nematodes, aluminum phosphide, and emamectin benzoate were the most effective treatments. After 2-3 months, in most of the treatments, there was a significant decline in RPW impulse burst rates. However, when applied as a spray, fipronil had only a minor effect. In the control treatment, the rates of impulse bursts in-creased until the trees died. The current study concluded that an IPM program utilizing ento-mopathogenic fungi or nematodes can be beneficial in the field for managing RPW. Furthermore, the use of an acoustic sensor can be beneficial in monitoring the activities of insect borers inside the tree trunk.