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Abraham S.,Laboratorio Of Investigaciones Ecoetologicas Of Moscas Of La Fruta Y Sus Enemigos Naturales | Abraham S.,CONICET | Rull J.,Institute Ecologia | Mendoza M.,Catedra de Terapeutica Vegetal | And 9 more authors.
Bulletin of Entomological Research | Year: 2014

The South American fruit fly, Anastrepha fraterculus, is a complex of cryptic species composed of at least seven morphotypes. Some of them, such as the Peruvian and Brazilian 1 morphotypes (which include Argentinean populations), exhibit strong pre-copulatory isolation, yet it is possible to obtain heterotypic crosses when forcing copulation of adults under laboratory conditions. The cross involving Peruvian males and Argentinean females produces F1 offspring with reduced viability in terms of egg hatch. This low hatchability could be caused by a reduced amount of sperm transferred to and stored by females mated with heterotypic males, which in turn could affect their post-copulatory behaviour. To test these hypotheses, we investigated sperm transfer and female mating and remating behaviour for homotypic and heterotypic crosses between adults of two morphotypes (Brazilian 1 [Argentina] and Peruvian [Peru]) of the A. fraterculus cryptic species complex. As reported before, Argentinean males and females mated earlier in the day than the other three mating combinations. Peruvian females engaged in shorter copulation times than Argentinean females. Peruvian females tended to store smaller quantities of sperm than Argentinean females, and almost a half of the crosses involving Argentinean males and Peruvian females were unsuccessful (no sperm transfer). However, there was no evidence that the cross between Peruvian males and Argentinean females resulted in storage of a critically small amount of sperm (posing risk of sperm shortage). Argentinean females were more willing to remate than Peruvian females, irrespective of male morphotype, but latency to remating was not affected by male or female morphotype. This study shows that mating behaviour differs between some of the A. fraterculus complex morphotypes, with female but not male morphotype determining female likelihood to remate. Copyright © 2013 Cambridge University Press.

Van Nieuwenhove G.A.,Laboratorio Of Investigaciones Ecoetologicas Of Moscas Of La Fruta Y Sus Enemigos Naturales | Ovruski S.M.,Laboratorio Of Investigaciones Ecoetologicas Of Moscas Of La Fruta Y Sus Enemigos Naturales
Florida Entomologist | Year: 2011

The aim of this study was to determine the optimal larval age for exposing Anastrepha fraterculus (Wiedemann) to Diachasmimorpha longicaudata (Ashmead) females to maximize parasitoid female offspring production under laboratory conditions in order to develop an efficient mass-rearing process for this biocontrol agent. Five age ranges of A. fraterculus larvae were assessed: 13 d-old (first instar), 46 d-old (second instar), 78 d-old (early third instar), 910 d-old (middle third instar), and 1112 d-old (late third instar). The number of D. longicaudata initiating ovipositor probing on a device with third instars of A. fraterculus was significantly higher than with others containing younger instars. Although female biased parasitoid offspring was recorded in all treatments using third instars as hosts, significantly more D. longicaudata females emerged from A. fraterculus pupae originated from middle and late third instars. However, the percentage of unemerged host puparia also increased significantly in both those host instar groups. Superparasitism, recorded as the number of first instar parasitoid head capsules per host, increased significantly as A. fraterculus larvae matured from second instars to late third instars. Nevertheless, the maximum average yield of parasitoid progeny was achieved using 912 d-old A. fraterculus larvae as hosts.

Suarez L.,Programa de Control y Erradicacion de Mosca de Los Frutos de San Juan ProCEM | Nieuwenhove G.A.V.,Laboratorio Of Investigaciones Ecoetologicas Of Moscas Of La Fruta Y Sus Enemigos Naturales | Murua F.,Programa de Control y Erradicacion de Mosca de Los Frutos de San Juan ProCEM | Bezdjian L.P.,Laboratorio Of Investigaciones Ecoetologicas Of Moscas Of La Fruta Y Sus Enemigos Naturales | And 4 more authors.
Florida Entomologist | Year: 2012

The objective of the present study was to assess the effect of different times of exposure to the host on parasitoid emergence rate, parasitoid progeny sex ratio, and on host mortality, as a step toward the development of an efficient mass-rearing system for the braconid Diachasmimorpha longicaudata (Ashmead) on larvae of the VIENNA 8 Temperature Sensitive Lethal Ceratitis capitata (Wiedemann) strain. The role of host-rearing substrate cues in stimulating the host-searching behavior of parasitoid females was also evaluated. Three exposure times (40, 60, and 120 min) were tested. One hundred 7 d-old host larvae were exposed to 25 female parasitoids per treatment. Larvae mixed with wheat-based rearing medium and larvae without medium were used in each test. A second set of treatments with the same method described above was conducted using late third-instars of the C. capitata wild-type strain. These experiments were carried out to assess the quality of the larvae of VIENNA 8 strain in producing D. longicaudata adults by comparing them with the larvae of the wild-type strain. Results indicated that the use of larvae of VIENNA 8 strain on their rearing diet at 40 min exposure time significantly increased overall parasitoid offspring production and decreased the host mortality level. Nevertheless, parasitoid emergence recorded from VIENNA 8 strain was notably lower than that recorded from the wild-type strain. Low parasitoid emergence levels and the prevalence of male-biased progeny recorded in all assays are obstacles to development of a parasitoid mass-rearing system using larvae of VIENNA 8 strain as host. Additional studies focusing on host exposure to parasitoids are needed to verify the effect of host larval quality on the production of D. longicaudata. .

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