Mass trapping to reduce pesticide use in olive groves

The olive fruit fly, Bactrocera oleae, causes the highest economic impact in Mediterranean olive crops. Pesticide applications are the most used strategy to control this pest. Through the NOVATERRA project, we provide new alternative control strategies to minimise the cost of using conventional pesticides. Mass trapping is an effective technique to reduce adult populations of B. oleae in olive crops. However, it must be complemented with specific support treatments, population monitoring, and evaluating the percentage of affected fruits to ensure total crop protection. We tested the control of the olive fly through mass trapping combined with low-impact strategies in three different regions and under different crop management systems in Spain and Portugal. During the first stage, two different mass trapping devices were compared in six trials. One device was selected for its ease of use, longer duration, and lower density per hectare.
The project focused on controlling the olive fly in three distinct olive production zones in Europe: two traditional orchards and one super-intensive plantation. We found no significant differences in the percentage of affected fruit between tested traps, orchards, or years, indicating similar effectiveness. The low percentage of damaged fruits in all trials supports mass trapping as a viable technique for managing the olive fruit fly. Conventional insecticides did not yield significantly lower percentages of attacked olives compared to support treatments like kaolin plus Spintor or kaolin alone. This consistency across all trials, areas, and years suggests that combining mass trapping with kaolin and/or Spintor sprays can be an effective low-impact method for managing B. oleae.