The South American Fruit Fly, Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae), is a major pest of fruit production in Brazil. This study was conducted to evaluate the stages of berry susceptibility and injuries caused by the fruit flies in different grape cultivars. The work was conducted in the field with 'Cabernet Sauvignon', 'Moscato Embrapa' and 'Isabel' cultivars, located in Bento Gonçalves, RS, in 2006 and 2007. Two couples of A. fraterculus were confined in grape bunchs in different phenological stages: berries pea-size, berries still hard and green, berries begin to colour and enlarge, and berries harvest-ripe. Significative berry dropping was recorded in 'Cabernet Sauvignon' cultivar when injured by A. fraterculus in the stages of berries pea-size and berries still hard and green; stage of berries pea-size in 'Moscato Embrapa' and stages of berries pea-size, berries still hard and green, berries begin to colour and enlarge in 'Isabel' cultivar. Deformation in berries was recorded when infestations were done in phases berries pea-size and berries still hard and green of 'Cabernet Sauvignon', 'Moscato Embrapa' and 'Isabel' cultivars. There was development of larvae to the pupa stage in 'Moscato Embrapa' cultivar.
south american fruit fly; development of larvae; berries dropping; Vitis labrusca; Vitis vinifera
