Sublethal Effects in Pest Management: A Surrogate Species Perspective on Fruit Fly Control

• Published in: Insects (Basel, Switzerland) Vol. 8; no. 3; p. 78
• Main Authors: Banks, John E, Vargas, Roger I, Ackleh, Azmy S, Stark, John D
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 29-07-2017; MDPI
• Subjects: Acute toxicity; Agrochemicals; Bactrocera cucurbitae; Bactrocera dorsalis; Biological control; Ceratitis capitata; Chemical pest control; Fecundity; Fruit flies; Fruits; Lefkovitch matrix; Life history; Mixed cropping; Orchards; Pest control; Pesticides; Pests; Species extinction; Sublethal effects; surrogate species; Tephritidae; Toxicity; Tephritidae; surrogate species; Lefkovitch matrix
• ISSN: 2075-4450; 2075-4450
• DOI: 10.3390/insects8030078

Tephritid fruit flies are economically important orchard pests globally. While much effort has focused on controlling individual species with a combination of pesticides and biological control, less attention has been paid to managing assemblages of species. Although several tephritid species may co-occur in orchards/cultivated areas, especially in mixed-cropping schemes, their responses to pesticides may be highly variable. Furthermore, predictive efforts about toxicant effects are generally based on acute toxicity, with little or no regard to long-term population effects. Using a simple matrix model parameterized with life history data, we quantified the responses of several tephritid species to the sublethal effects of a toxicant acting on fecundity. Using a critical threshold to determine levels of fecundity reduction below which species are driven to local extinction, we determined that threshold levels vary widely for the three tephritid species. In particular,
was the most robust of the three species, followed by
, and then
, suggesting individual species responses should be taken into account when planning for area-wide pest control. The rank-order of susceptibility contrasts with results from several field/lab studies testing the same species, suggesting that considering a combination of life history traits and individual species susceptibility is necessary for understanding population responses of species assemblages to toxicant exposure.