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Rempoulakis P.,International Atomic Energy Agency | Rempoulakis P.,Israel Agricultural Research Organization | Afshar N.,Queen Mary, University of London | Osorio B.,National Polytechnic Institute of Mexico | And 10 more authors.

Μetal cofactors are required for enzymatic catalysis and structural stability of many proteins. Physiological metal requirements underpin the evolution of cellular and systemic regulatory mechanisms for metal uptake, storage and excretion. Considering the role of metal biology in animal evolution, this paper asks whether metal content is conserved between different fruit flies. A similar metal homeostasis was previously observed in Drosophilidae flies cultivated on the same larval medium. Each species accumulated in the order of 200 µg iron and zinc and approximately ten-fold less manganese and copper per gram dry weight of the adult insect. In this paper, data on the metal content in fourteen species of Tephritidae, which are major agricultural pests worldwide, are presented. These fruit flies can be polyphagous (e.g., Ceratitis capitata) or strictly monophagous (e.g., Bactrocera oleae) or oligophagous (e.g., Anastrepha grandis) and were maintained in the laboratory on five distinct diets based on olive oil, carrot, wheat bran, zucchini and molasses, respectively. The data indicate that overall metal content and distribution between the Tephritidae and Drosophilidae species was similar. Reduced metal concentration was observed in B. oleae. Feeding the polyphagous C. capitata with the diet of B. oleae resulted in a significant quantitative reduction of all metals. Thus, dietary components affect metal content in some Tephritidae. Nevertheless, although the evidence suggests some fruit fly species evolved preferences in the use or storage of particular metals, no metal concentration varied in order of magnitude between these two families of Diptera that evolved independently for over 100 million years. © 2014 The Author(s) Source

Gavriel S.,Hebrew University of Jerusalem | Gazit Y.,The Israel Cohen Institute for Biological Control | Leach A.,Center for Environmental Policy | Mumford J.,Center for Environmental Policy | Yuval B.,Hebrew University of Jerusalem
Entomologia Experimentalis et Applicata

The success of the sterile insect technique (SIT) for the control of the Mediterranean fruit fly or medfly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), depends largely on the ability of sterile flies to spread in the target area and compete with the wild males for wild females. Our objectives in the present study were three-fold: (1) to evaluate the dispersal ability of sterile male medflies and compare their spatial dispersion patterns with that of wild males, (2) to evaluate how different release methods affect subsequent spatial dispersal, and (3) to determine whether manipulating the pre-release diet of sterile males affects their dispersal. To achieve these objectives, we conducted three experiments in the field where we quantified and analyzed the spatial and temporal dispersal patterns of sterile medflies and the dispersion of resident wild males. Overall, ca. 5% of the released sterile flies were recaptured 100m from the release point, and ca. 2% were recaptured 200m from the release point. The released flies rarely survived longer than 5-7days. We repeatedly found that the spatial dispersion patterns of sterile males significantly correlated with those of wild males. Release methods strongly affected subsequent fly dispersal in the field as significantly more flies were recaptured following a scattered release vs. a central one. Finally, we show that enriching sterile fly pre-release diet with protein did not affect subsequent dispersal in the field. We conclude that sterile males are able to match the dispersion patterns of wild males, an outcome that is highly important for SIT success. Large releases from central points distant from each other may leave many areas uncovered. Accordingly, scattered releases, repeated twice a week, will provide better coverage of all available aggregations sites. The spatial performance of protein-fed males suggests that pre-release diet amendments may be used without detriment as a sexual stimulant in SIT programs. © 2011 The Authors. Entomologia Experimentalis et Applicata © 2011 The Netherlands Entomological Society. Source

Argov Y.,The Israel Cohen Institute for Biological Control | Schatz B.,Hebrew University of Jerusalem | Gazit Y.,The Israel Cohen Institute for Biological Control
Biocontrol Science and Technology

The citrus leafminer, Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae) (CLM), is a citrus pest indigenous to Southeast Asia. It was discovered in Israel in 1994. The pest attacks the young foliage of citrus, and damage is caused by the larvae tunnelling under the epidermis of young leaves, leading to foliage destruction. The present study documents basic biological parameters of three exotic eulophid wasps in the laboratory: Semielacher petiolatus, Quadrastichus citrella and Teleopterus sp. S. petiolatus females preferred to lay eggs in the 3rd larval instar of CLM, but did not lay eggs in the 1st instar. Its development ranged from 9 to 14 days. Female longevity was 30.2±5.9 days, its daily oviposition was 12.16±0.68 eggs/day, the total number of eggs oviposited per female was 278.9±74.1, and the number of CLM larvae parasitised was 260.0±68.3. Q. citrella preferred to lay in the 3rd and 4th instar larvae, but not in the 1st instar, its development ranged from 9 to 14 days, female longevity was 40.6±1.9 days, oviposition came to 8.3±0.6 eggs/day, the total number of eggs oviposited was 281.3±64.9/female and the number of parasitised CLM larvae was 276.5±63.7. Teleopterus sp. preferred to lay eggs in the 3rd larval instar, its development required 11-17 days, female longevity was 28.7±3.8 days, its daily number of offspring was 5.2±0.38 offspring/day and with emergence of 138.9±27.7 offspring/female. This knowledge enabled us to maintain high quality cultures for their releases in Israel. © 2012 Taylor and Francis Group, LLC. Source

Kaspi R.,University of California at Davis | Kaspi R.,The Israel Cohen Institute for Biological Control | Yuval B.,Hebrew University of Jerusalem | Parrella M.P.,University of California at Davis
Animal Behaviour

Host feeding is common among synovigenic parasitoid wasps and is the mechanism through which they obtain nutrients for egg production. Upon host discovery, female wasps make a series of decisions that influence their host feeding and oviposition activities. Theoretical and empirical studies have shown that host availability is one of the factors that may affect these decisions. Diglyphus isaea, a synovigenic ectoparasitic wasp, parasitizes and kills (by feeding on or stinging) larval stages of agromyzid leafminer flies. We found that in the presence of large populations of adult leafminer flies, Liriomyza trifolii, the parasitoid wasp increased its host-killing behaviour, which appeared to be associated with a trend for increased protein uptake. Our study suggests that anticipated future host availability, which is based on a 'host cue detour' (sensu 'infochemical detour'), affects the host-killing and host-feeding behaviour of this parasitoid wasp. © 2011 The Association for the Study of Animal Behaviour. Source

Argov Y.,The Israel Cohen Institute for Biological Control | Blanchet A.,European Biological Control Laboratory | Gazit Y.,The Israel Cohen Institute for Biological Control
Biological Control

Three braconid species that parasitize the Mediterranean fruit fly (Medfly) Ceratitis capitata (Wiedemann) were recently imported into Israel. Several of their key biological parameters were studied. The longevities of the egg-attacking parasitoids Fopius arisanus (Sonan) and Fopius ceratitivorus (Wharton), and the larval parasitoid Diachasmimorpha kraussii (Fullaway) in the laboratory at 24 ± 1 °C were 42.1 ± 2.0. d, 36.9 ± 2.0. d and 18.6 ± 1.6. d, respectively. These wasps oviposited for 17.8 ± 0.9. d, 17.7 ± 0.8. d and 12.7 ± 1.6. d, during which they produced 133.0 ± 20.5, 103.9 ± 12.4 and 282.7 ± 43.1 offspring/female, respectively. The daily fecundity rates were 6.8 ± 1.8, 5.0 ± 1.0 and 15.3 ± 2.0, offspring/female/day, with sex ratios (females) of 43.0 ± 7.9%, 69.4 ± 3.3% and 59.0 ± 1.8%, respectively. F. arisanus and F. ceratitivorus preferred to oviposit into 48 h-old eggs, while D. kraussii preferred to oviposit in 7 d-old (late 2nd to early 3rd instar) larvae, a spherical, artificial oviposition unit was developed for the egg-prepupal parasitoid F. ceratitivorus. © 2011 Elsevier Inc. Source

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