Oviposition performance of tephritid polyphagous Anastrepha fraterculus and Ceratitis capitata during three periods of exposure to fruit

Abstract Our study evaluated the oviposition behaviour of Anastrepha fraterculus (Wiedemann, 1830) and Ceratitis capitata (Wiedemann, 1824) in five fruit species. Apples, guavas, mangoes, peaches and tangerines were exposed to infestation for 6, 12 and 24 hours. Anastrepha fraterculus and C. capitata showed different oviposition behaviour in apples and tangerines and similar oviposition behaviour in guavas, mangoes and peaches. There was a positive correlation between infestation time and pupae/kg, as well as between pupae/fruit and the survival rate of the immature (pupal viability). In this study, we present discussions about the oviposition behaviour of flies and the host infestation index. This index can reflect the reproductive capacity that each fruit species offers for each fly species. Here, we see an adult recovery rate greater than 89% in the highest infestation index observed in guava (185 A. fraterculus per unit fruit) and peach (220 C. capitata per unit fruit). Understanding the reproductive capacity of each host can help with risk analysis and the management of fruit flies.

Toward an Automated Identification of Anastrepha Fruit Flies in the fraterculus group (Diptera, Tephritidae)

In this study, we assess image analysis techniques as automatic identifiers of three Anastrepha species of quarantine importance, Anastrepha fraterculus (Wiedemann), Anastrepha obliqua (Macquart), and Anastrepha sororcula Zucchi, based on wing and aculeus images. The right wing and aculeus of 100 individuals of each species were mounted on microscope slides, and images were captured with a stereomicroscope and light microscope. For wing image analysis, we used the color descriptor Local Color Histogram; for aculei, we used the contour descriptor Edge Orientation Autocorrelogram. A Support Vector Machine classifier was used in the final stage of wing and aculeus classification. Very accurate species identifications were obtained based on wing and aculeus images, with average accuracies of 94 and 95%, respectively. These results are comparable to previous identification results based on morphometric techniques and to the results achieved by experienced entomologists. Wing and aculeus images produced equally accurate classifications, greatly facilitating the identification of these species. The proposed technique is therefore a promising option for separating these three closely related species in the fraterculus group.