Blueberry cultivation in mountainous areas of southeastern Brazil as a suitable environment for Drosophila suzukii establishment

The spotted-wing drosophila, Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae), is an invasive pest of thin-skinned and stone fruits with growing economic impact worldwide. In Brazil, it was first reported in 2013 and has since spread across major fruit-producing states. Although previously detected in Rio de Janeiro (RJ), records were limited to isolated individuals, never in commercial orchards. Here, we provide the first evidence of D. suzukii establishment in a commercial ‘Biloxi’ blueberry, Vaccinium corymbosum Linnaeus, field in Sapucaia, RJ. Initial vinegar traps captured seven females, confirmed in the laboratory. Subsequent banana–yeast bait traps collected both sexes, including one male, confirming establishment. Emergence assays from naturally damaged fruits demonstrated reproductive success, resulting in approximately 279 individuals (110 males and 169 females) from a total of 1.6 kg of damaged fruits. Monitoring also detected Zaprionus spp. (Diptera: Drosophilidae), another invasive drosophilid associated with fruit damage. To assess management options, we evaluated susceptibility of this D. suzukii population to imidacloprid. Bioassays showed that exposure to 0.140 mg/mL (LC₅₀ for a susceptible reference strain) killed approximately 50% of adults, indicating local susceptibility, in contrast to reduced susceptibility reported in other Brazilian strains. Collectively, these findings confirm D. suzukii establishment in a new blueberry-producing region, reveal potential phytosanitary risks, and suggest that chemical control options remain effective locally. This integrated evidence highlights the importance of early monitoring and management strategies to safeguard Brazil’s expanding blueberry industry.

Keywords:
Fruit protection; invasive pests; Neotropical orchards; Spotted-wing drosophila; Vaccinium corymbosum