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Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) also known as spotted-wing drosophila (SWD), is a pest native to Southeast Asia. In the last few decades, the pest has expanded its range to affect all major European and American fruit production regions. SWD is a highly adaptive insect that is able to disperse, survive, and flourish under a range of environmental conditions. Infestation by SWD generates both direct and indirect economic impacts through yield losses, shorter shelf life of infested fruit, and increased production costs. Fresh markets, frozen berries, and fruit export programs have been impacted by the pest due to zero tolerance for fruit infestation. As SWD control programs rely heavily on insecticides, exceedance of maximum residue levels (MRLs) has also resulted in crop rejections. The economic impact of SWD has been particularly severe for organic operations, mainly due to the limited availability of effective insecticides. Integrated pest management (IPM) of SWD could significantly reduce chemical inputs but would require substantial changes to horticultural management practices. This review evaluates the most promising methods studied as part of an IPM strategy against SWD across the world. For each of the considered techniques, the effectiveness, impact, sustainability, and stage of development are discussed.

Drosophila suzukii Matsumura, an endemic pest in southeast Asia, has invaded Europe and the U.S.A. Unlike most of its closely related sibling species, the serrated ovipositor of D. suzukii permits ovipositing in undamaged fresh fruits. In the present study, volatiles are identified from host plants that are potentially involved in D. suzukii host recognition and oviposition behaviour. It is shown that mated females are attracted to volatiles emitted from intact fruits. The antennally‐active suite of compounds released from the fresh fruits is identified by gas chromatography coupled with electroantennographic detection, as well as gas chromatography‐mass spectrometry. In olfactometer bioassays, mated females are significantly attracted to an electroantennographically active volatile, isoamyl acetate, when tested at 10 µg of synthetic compound in a rubber septa, which has a release rate comparable to that of fresh fruits. In addition, a genomic survey shows that D. suzukii not only possesses the full repertoire of genes encoding odorant receptors activated by isoamyl acetate in D. melanogaster, but also that one of the genes, OR67a, is represented by five duplicated copies. These results indicate that D. suzukii uses olfactory cues to select oviposition sites. The identification of volatiles emitted by host fruits that attract D. suzukii may aid in the development of a selective and efficient synthetic lure for monitoring this pest. As a close relative of Drosophila melanogaster, D. suzukii provides a unique opportunity for understanding the physiological mechanisms involved in the shift of this species from use of rotten to ripe fruits for oviposition.

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Drosophila suzukii (Matsumura; Diptera: Drosophilidae) is a key pest of sweet cherry and small fruits worldwide. The present studies were designed to describe the reproductive physiology in both sexes, through dissections of their reproductive organs. We extensively dissected female D. suzukii throughout the season from 2013 to 2016 and classified the reproductive status flies based on five recognizable ovarian maturation stages: 1) no ovaries; 2) unripe ovaries 3) ripening eggs in ovarioles; 4) mature eggs in ovarioles; and 5) mature eggs in the abdomen. Development was examined as a function of calendar days as well as degree-days (DD). Results obtained from winter collections revealed that females collected from November to March contained a lower percentage of mature eggs than females collected from April to September. These data suggest that environmental conditions during the dormant period induce reproductive diapause. Oogenesis likely increased with an increase in mean monthly temperatures and DD. The first overwintered females with mature eggs were dissected as early as 21 February 2014 in Trento (7 DD). Additionally, we found that a low proportion of males (less than 50%) had sperm in their testes between January and March, yet during the same period females already have sperm stored in their spermathecal. Ivy berries was an alternative but unfavorable non-crop host during the late dormant period, as evidenced by emergence of smaller adults when compared to individuals emerging from cherry fruits. This study showed that D. suzukii females have great potential for oviposition early in the season, posing a risk to early season maturing crop hosts.