Efficacy of attract-and-kill techniques in controlling Bactrocera oleae (Diptera: Tephritidae) in a highly variable olive production scenario

The management of the olive fly using sustainable methods includes strategies based on attract-and-kill techniques. Although some studies have shown that lure-and-kill and mass-trapping methods can be effective in certain contexts, their performance under conditions of highly variable olive production remains unclear. In this study, we evaluated the effectiveness of two sustainable control techniques in olive groves located at the northernmost boundary of olive cultivation in Europe. The efficacy of a lure-and-kill product (SpintorTM Fly) and a mass-trapping product (Flypack® Dacus Trap) was assessed over a three-year period by monitoring olive fly population density and infestation levels. We found that the efficacy of attract-and-kill techniques varied over the years. In years of abundant production, the high availability of fruits may reduce the detectability of damage. In contrast, in low production years, the limited number of fruits can lead to higher infestation rates, potentially reducing the effectiveness of the control techniques. Both techniques tested, particularly lure-and-kill, can help maintain low Bactrocera oleae population densities. However, they are insufficient to maintain fruit infestation at acceptable levels during years of low olive production, when the adoption of control measures is not economically justified.