Feijoa (Acca sellowiana [Berg] Burret; Myrtaceae) is an evergreen shrub or short tree, 2 to 6 m in height (Weston 2010), and native to the highlands of southern Brazil and northeast Uruguay (Barni et al. 2004). Its fruit is similar in appearance, size, and texture to the common guava (Psidium guajava L.; Myrtaceae), but with the flesh having a distinctive sweet-tangy taste and a very aromatic flavor, and with a non-edible green skin (Amarante & Santos 2011). In addition, it is a good source of vitamins, minerals, and secondary metabolites with antibacterial, antioxidant, antiallergic, and immunological properties (Weston 2010).

Feijoa has been cultivated commercially in Colombia, the USA, the former Soviet Republics of the Caucasus region, and especially in New Zealand (Barni et al. 2004). In New Zealand, about 500 t of feijoa fruits are produced annually, and domestic sales generate around 1.7 million dollars (Plant and Food Research Institute of New Zealand Ltd. 2013). Despite the commercial potential of its fruit, feijoa is almost unknown in Brazil (Ducroquet et al. 2000), and its production faces several phytosanitary problems involving pests, especially the South American fruit fly, Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae), with infestations of up to 100% during the fruit ripening period (Ducroquet et al. 2000), and the guava weevil, Conotrachelus psidii Marshall (Coleoptera:. Curculionidae), whose damage can lead to loss of up to almost 100% of the fruits in monoculture (Luckmann et al. 2009).

Recently, in addition to specimens of A. fraterculus and C. psidii that emerged from A. sellowiana fruits collected in the 2015/2016 season, we also obtained adult specimens of Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), commonly known as the spotted wing drosophila. This is the first record of D. suzukii in A. sellowiana fruits collected in an orchard located in Lages, Santa Catarina, Brazil.

Acca sellowiana fruits bearing feeding and oviposition damage caused by C. psidii (Fig. 1) were collected from different trees in a feijoa orchard in the Estação Experimental de Lages (EEL) of the Empresa de Pesquisa Agropecuária e Extensão Rural de Santa Catarina (Epagri) in Lages, Santa Catarina, Brazil (27.8086°S, 50.3306°W), in Mar 2016. The fruits were placed in plastic containers and taken to the Laboratório de Pesquisa em Entomologia of the Centro de Ciências Agroveterinárias da Universidade do Estado de Santa Catarina (CAV-UDESC) in Lages, where they were washed in a 1% solution of sodium hypochlorite, transferred to plastic pots (750 mL) covered with voile and containing sterile moist vermiculite, and kept at 25 ± 2 °C, 70 ± 10% RH, and a 12:12 h L:D photoperiod. Larvae, pupae, and adults that emerged from the fruits were collected every 2 d. Adult drosophilids were killed in a freezer, stored in 70% alcohol, and observed under a stereomicroscope for species identification according to EPPO (2013). Voucher specimens of D. suzukii were stored in 70% alcohol and deposited at the Museu de Entomologia of the CAVUDESC.

Drosophila suzukii is native to Asia but has invaded Europe and North and South America (Hauser et al. 2009; Calabria et al. 2012; Deprá et al. 2014), where it has become a pest of soft and thin-skinned fruit crops as blackberries, blueberries, cherries, mulberries, raspberries, strawberries, some wine grape cultivars, and ornamental plants (Lee et al. 2011, 2015; Yu et al. 2013; Ioriatti et al. 2015). This is the first record of D. suzukii in feijoa. In addition, these results demonstrate the feasibility of feijoa as an alternative host for D. suzukii. Skin thickness of the feijoa fruit can reach 12 mm (Ducroquet et al. 2000), thus being considered a species of thick-skinned fruit and, therefore, unsuitable for D. suzukii oviposition, because the adult fly is unable to successfully lay eggs in the fruit flesh (Stewart et al. 2014). Although it is unlikely that D. suzukii may lay eggs in hard and thick-skinned fruit crops, this species is able to complete its development when thick-skinned fruits are damaged, rotten, or overripe (Steffan et al. 2013; Stewart et al. 2014). It has been reported before that feeding and oviposition damage caused by adults of C. psidii in feijoa fruit facilitate infections by pathogens such as Colletotrichum sp. (Phyllachoraceae) (Ducroquet et al. 2000) and, similarly, could have enabled females of D. suzukii to deposit eggs in the lesions present in the skin of the fruit (Fig. 1).

Our knowledge on preferred or alternative hosts of D. suzukii has been increasing from surveys done outside growing areas (Lee et al. 2015; Poyet et al. 2015). Reporting feijoa as an alternative host for D. suzukii is important because it has thick-skinned fruits, thus showing the possibility of this pest to adapt to different hosts available in the colonization areas. In addition, A. sellowiana is a fruit crop of economic importance in many countries, mainly in Asia, North and South America, and Oceania, and D. suzukii may become a pest of feijoa in these regions because it is native to Asia and is widely distributed in North America and Europe (Asplen et al. 2015).

In conclusion, we can affirm that D. suzukii is prevalent in Brazil. Furthermore, it can cause damage to A. sellowiana fruits and perhaps other native or cultivated fruit crops with thick-skinned fruits.

Fig. 1.

Acca sellowiana fruit showing characteristic symptoms of Conotrachelus psidii attack: damage caused by feeding (black circles) and oviposition (white circles). An adult male of C. psidii is indicated by a black arrow, and an egg-laying adult female of Drosophila sp. is indicated by a white arrow.

The authors thank the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Rede Guarani/Serra Geral - FAPESC TO 2015TR10672, and the Núcleo Agroecologia e Saúde Ambiental FAPESC/CNPq TO TR2012000363 for the financial support.