Food attractants for mass trapping of fruit flies (Diptera: Tephritidae) and its selectivity for beneficial arthropods
Fruit fly control in Uruguay is based mainly on toxic baits which are insufficient to reduce the damage caused by these pests. Therefore, alternative management measures such as mass trapping gain relevance for control of flies. Attractants commercially available were designed mainly for Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). However, they also should be attractive to Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) in our fruit orchards. The aim of this research was to evaluate the effectiveness of food-based attractants for the capture of sexually immature females of C. capitata and A. fraterculus, as well as their selectivity on the populations of beneficial arthropods (pollinators, predators, and parasitoids). Seven attractants were evaluated in 3 commercial fruit crops during 2 seasons; 4 commercial attractants (hydrolyzed protein, liquid trimethylamine, trimethylamine diffuser card, and ammonium acetate + putrescine diffuser card), 20% natural Acca sellowiana (O. Berg) O. Berg (Myrtaceae) juice, 6% sugarcane molasses, and Torula yeast. The attractants were placed in McPhail traps, which were checked each wk and all captured arthropods were removed, counted, and classified. Captured female tephritids were dissected to determine the presence of eggs. All commercial attractants evaluated were effective at capturing sexually immature females of C. capitata in the 3 fruit crops evaluated during both seasons. Hydrolyzed protein, liquid trimethylamine, and trimethylamine diffuser card were effective at capturing young females of both species. Most of the captures are post-harvest, so we suggest not moving traps after commercial harvest. These attractants also were selective, capturing few beneficial arthropods. Sugarcane molasses and pineapple guava juice were not effective at capturing fruit fly females.