Captures of oriental fruit flies and melon flies (Diptera: Tephritidae) in traps baited with Torula yeast borax solution or 2- or 3-component synthetic food cones in Hawaii.
Food-based traps are an integral component of detection systems for invasive fruit fly (Diptera: Tephritidae) species which pose a serious threat to many agricultural crops. A commonly used bait is torula yeast borax solution; however, it is attractive for relatively short intervals (1-2 wk), necessitating frequent bait replacement. A dry, synthetic food bait that incorporates several components into a single matrix (or food cone) has been developed and appears to be effective for as long as 4 to 10 wk in field trials with the Mediterranean fruit fly (Ceratitis capitata [Wiedemann]) and the Caribbean fruit fly (Anastrepha suspensa [Loew]) (both Diptera: Tephritidae). Based on these results, food cones are used now in several large-scale fruit fly detection programs even though their attractiveness to other economically important tephritids, most notably Bactrocera and Zeugodacus species, has not been well studied. The goal of this study was to compare the captures of oriental fruit fly (Bactrocera dorsalis [Hendel]) and melon fly (Zeugodacus cucurbitae [Coquillett]) (both Diptera: Tephritidae) in traps baited with torula yeast borax solution with captures in traps baited with 3-component (ammonium acetate, putrescine, and trimethylamine) or 2-component (ammonium acetate and putrescine) food cones. Data from wild and released flies of both species showed that captures were significantly higher in traps baited with the torula yeast borax than those with either type of synthetic formulation. Implications of this finding for trapping programs are discussed.