Characterization and attractiveness of <i>Citrus</i> spp. essential oil-based formulations to <i>Drosophila suzukii</i> under greenhouse and field conditions in Morocco

Abstract

Drosophila suzukii is a major invasive pest causing significant economic damage to soft-skinned fruits globally. Females lay eggs in healthy, ripening fruits, making chemical control often ineffective. Management still relies heavily on insecticides, raising concerns about resistance, environmental contamination, and harm to non-target species. This study evaluated eco-friendly alternatives, assessing the attractiveness of nine essential oil formulations from Citrus sinensis fresh zest (EO1), C. aurantium dried flowers (EO2), and C. limon fresh zest (EO3) under greenhouse conditions, and six formulations under field conditions. Three concentrations (0.1%, 0.05%, 0.02%) were tested. In the greenhouse, the 0.02% EO1 formulation (F1) captured twice as many females (5 ± 1.41) as the control. Field trials in a Moroccan raspberry plantation confirmed this, with F1 recording the highest female captures (20.33 ± 5.86), significantly exceeding the positive control (9.33 ± 8.33). Higher concentrations showed reduced attraction, indicating a dose-dependent response. GC–MS analysis identified D-Limonene as the dominant component (>90%). The formulation demonstrated selective attraction to D. suzukii, with minimal bycatch of pollinators and natural enemies. These results highlight the potential of low-concentration C. sinensis essential oil as an effective, selective, and environmentally compatible tool for integrated pest management of D. suzukii through mass trapping or monitoring.