Mealworm Frass as a Novel Insect Food-Based Attractant: The Case of Bactrocera oleae (Diptera: Tephritidae)

Abstract

The management of Bactrocera oleae (Rossi, 1790) has relied on chemical insecticides, applied as bait or cover sprays. However, concerns over insecticide resistance and environmental impact have driven the search for more effective and eco-friendly alternatives, such as mass trapping. The aim of the study was to assess a novel food-based attractant, derived from Tenebrio molitor Linnaeus, 1758 excreta “Frass”, for its attractiveness to B. oleae adults compared to widely used commercial food-based attractants. Over a four-year period, five field trials were conducted in two organic olive groves in Crete, Greece, using a randomized complete block design with five or six replicate blocks. Results showed that frass-based attractants captured significantly higher number of B. oleae adults than the other tested attractants. Additionally, trap–attractant combinations were assessed to determine the most efficient mass-trapping system. Frass-based attractant deployed in Anel or container traps demonstrated significantly higher attractiveness than all commercial traps and lures tested. The significant advantages of mealworm frass as an attractant highlight its potential to enhance the monitoring and suppression of B. oleae in olive orchards. Its consistent performance, sustainability, and environmental safety make it a promising tool in integrated pest management strategies.