Oviposition deterrent activity of Anastrepha fraterculus

BACHMANN, GUILLERMO E.; FERNÁNDEZ, PATRICIA C.; VERA, MARÍA T; CLADERA, JORGE L; SEGURA, DIEGO F

Tapachula

Simposio; 10th International Symposium on. Fruit lies of Economic Importance; 2018

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Background: After oviposition, females from several tephritid species, including A. fraterculus, deposit host marking pheromones (HMPs) that reduce the probability of further egg laying events, and consequently larval competition. HMPs were isolated in other Anastrepha spp. through dissolution of their feces in water. The rejection of fruit as oviposition substrate caused by HMPs has generated interest as a potential tool to reduce infestation levels, as part of an integrated pest management program. In order to promote the development of non-contaminant control tools, we evaluated the deterrent effect of A. fraterculus feces on the behavior of conspecific females.Methods: The feces of A. fraterculus were dissolved in water and the solution was used in the following two experiments. 1- Behavioral recordings: two cylindrical slices of pear (2 cm in diameter, 0.5 cm in height and with their rinds intact) were placed in a Petri dish, separated 5 cm from each other. One of the slices was treated with the solution and other was non-treated. The Petri dish was introduced in a glass container that housed one mated female. The slice visited and the occurrence of oviposition were recorded. 2- Oviposition patterns: groups of 4 mated females were offered artificial oviposition substrates (10 ml vials filled with colored water and wrapped in Parafilm) treated or non-treated with the solution. After 30 min, the vials were removed and the number of vials that were accepted for oviposition and the number of eggs laid, were recorded.Results: Behavioral recording showed that treated slices of pear were less frequently visited than control, non-treated slices. Once on the slice, females rejected to lay eggs more frequently on treated slices. In the Oviposition patterns experiment, females laid less eggs in treated substrates, and these substrates were chosen less frequently for oviposition.Conclusion: The results suggest that the feces of A. fraterculus contain compounds that trigger oviposition deterrence. Further studies on the chemical composition of the solution would allow the identification of the compounds that constitute the HMP of A. fraterculus.