Population Dynamics and Parasitism Rates of Ceratitis capitata, Anastrepha fraterculus, and Drosophila suzukii in Non-Crop Hosts: Implications for Area-wide Management of Pest Fruit Flies

Abstract

Non-crop host plants inhabiting wild vegetation areas surrounding crops strongly influence the dynamics and abundance of polyphagous pest fruit flies Ceratitis capitata (Cc), Drosophila suzukii (Ds), and Anastrepha fraterculus (Af). The two former species are dangerous invasive pests widespread in all Argentinean fruit-producing regions, whereas the latter species, native to the Neotropics, coexists with those exotic species in northern Argentina. Integrated and eco-friendly management strategies are needed against those pests, targeting both crop and non-crop areas. Therefore, this study assessed the abundance of the three aforementioned pest dipterans, their seasonal infestation levels in five non-crop fruit species, relationships with competing saprophytic drosophilids, and natural parasitism. Fruit surveys were performed in a disturbed wild habitat from northwestern Argentina over 40months. Results mainly revealed the highest abundance of Af followed by Cc and Ds, although saprophytic drosophilids were only predominant from ground fruit samples. Spatiotemporal overlaps of different host fruit availability enabled continuous and suitable sources for pest proliferation throughout year. Population peaks of both exotic pests coincided with the highest availability of peach from December to January, whereas the Af population peaked during guava fruiting from February to April. These pest flies were attacked mainly by generalist parasitoids that could be useful in conservation and augmentative biological control of these pests.