ABSTRACT Healthy peach fruit is not considered a preferred host for Drosophila suzukii (Matsumura); however, it becomes a more preferable host when damaged. Thus, damaged peach fruit is of importance not only in terms of economic losses, but also because it serves as a reservoir for this fly species. This work aimed to evaluate the suitability of peaches mechanically damaged or harboring the brown rot disease as hosts for D. suzukii compared to hosts for which they have a low (undamaged peach) and high (undamaged strawberry) preference. Damaged peaches were as susceptible as undamaged strawberries. Fungus infection alone did not increase the susceptibility of peaches compared to undamaged peaches. This information should be considered when an Integrated Pest Management program is defined in a scenario of different species of fruit production.

Resumo: O objetivo deste trabalho foi avaliar a suscetibilidade de genótipos de videira à drosófila-da-asa- manchada, Drosophila suzukii (Diptera: Drosophilidae), em bagas de uva intactas e em bagas infestadas após a ocorrência de puncturas, causadas pela oviposição da mosca-das-frutas sul-americana [Anastrepha fraterculus (Diptera: Tephritidae)] ou por danos mecânicos (alfinetes). Os experimentos foram realizados em laboratório, a 22±1°C, umidade relativa de 65±10% e fotófase de 12 horas. A suscetibilidade foi avaliada para 18 genótipos de videira, em bagas intactas submetidas às fêmeas de D. suzukii. O potencial de interação foi verificado em bagas de uva 'Italia', cuja epiderme foi danificada por puncturas de A. fraterculus ou por alfinete, em comparação a frutos de morango 'Albion'. As cultivares de Vitis labrusca 'Niagara Rosada' e 'Concord' não foram infestadas por D. suzukii, e cinco dos oito genótipos que foram infestados são cultivares melhoradas. A infestação de D. suzukii em bagas de uva 'Italia' com danos mecânicos, feitos com um alfinete ou pela oviposição de A. fraterculus, foi semelhante à de bagas íntegras. Há baixa adequação hospedeira de videiras a D. suzukii, mesmo com a presença de danos. As cultivares 'Benitaka', 'BRS Vitória' e 'BRS Morena' são as mais suscetíveis a D. suzukii.

Abstract: The objective of this work was to evaluate the susceptibility of vine genotypes to the spotted wing drosophila, Drosophila suzukii (Diptera: Drosophilidae), on uninjured grapes and on infested grapes after the occurrence of puncture sites, caused either by the oviposition of South American fruit fly [Anastrepha fraterculus (Diptera: Tephritidae)] or by mechanical damage (pins). The experiments were carried out in laboratory at 22±1°C, 65±10% relative humidity, and 12-hour photophase. Susceptibility was evaluated on intact grapes of 18 genotypes subjected to D. suzukii females. The interaction potential was assessed on 'Italia' grapes, whose epidermis was damaged either by punctures caused by A. fraterculus or by pins, in comparison to 'Albion' strawberries. The 'Niagara Rosada' and 'Concord' Vitis labrusca cultivars were not infested by D. suzukii, and five out of the eight infested genotypes are improved varieties. Infestation of D. suzukii on 'Italia' grapes, with mechanical damage made by a pin or by A. fraterculus oviposition, was similar to that on undamaged grapes. There is a low suitability of host vines to D. suzukii, even with the presence of previous injuries. The 'Benitaka', 'BRS Vitória', and 'BRS Morena' vine cultivars are the most susceptible genotypes to D. suzukii.