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Hidalgo K, Beaugeard E, Renault D, Dedeine F, Lécureuil C. Physiological and biochemical responses to thermal stress vary among genotypes in the parasitic wasp Nasonia vitripennis. JOURNAL OF INSECT PHYSIOLOGY 2019; 117:103909. [PMID: 31295454 DOI: 10.1016/j.jinsphys.2019.103909] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 06/26/2019] [Accepted: 06/28/2019] [Indexed: 06/09/2023]
Abstract
In ectotherm species such as insects, thermal fluctuations represent a major environmental factor driving development, survival and reproduction of individuals. Reproductive traits are particularly sensitive to heat stress that can induce a permanent sterility, or at least hypofertility, of adult males. This study aims to compare physiological and biochemical responses associated to male performances to an exposure of 24 h to moderately high temperature (36 °C) among three inbred lines of N. vitripennis (AsymC, Cor, Oul). Cor males showed very specific metabolic adjustments compared to the two other lines. By contrast, Oul males showed stronger phenotypic adjustment of its life cycle, and produced metabolic water to compensate water loss by heat stress. Finally, AsymC males had probably more difficulties to acclimate at 36 °C, even for a short period, as their adult longevity was significantly reduced. Thus, the ability of developmental plasticity in N. vitripennis males exposed to heat stress appears to be dependent of their genotypes.
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Affiliation(s)
- Kevin Hidalgo
- Institut de Recherche sur la Biologie de l'Insecte UMR 7261 CNRS Université de Tours, UFR Sciences et Techniques, Parc Grandmont, Tours, France
| | - Erika Beaugeard
- Institut de Recherche sur la Biologie de l'Insecte UMR 7261 CNRS Université de Tours, UFR Sciences et Techniques, Parc Grandmont, Tours, France
| | - David Renault
- Université de Rennes 1, UMR CNRS 6553 Ecobio, Campus de Beaulieu, 263 Avenue du Gal Leclerc, CS 74205 35042 Rennes Cedex, France; Institut Universitaire de France, 1 rue Descartes, 75231 Paris Cedex 05, France
| | - Franck Dedeine
- Institut de Recherche sur la Biologie de l'Insecte UMR 7261 CNRS Université de Tours, UFR Sciences et Techniques, Parc Grandmont, Tours, France
| | - Charlotte Lécureuil
- Institut de Recherche sur la Biologie de l'Insecte UMR 7261 CNRS Université de Tours, UFR Sciences et Techniques, Parc Grandmont, Tours, France.
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Lüthi C, Álvarez-Alfageme F, Romeis J. The bean α-amylase inhibitor αAI-1 in genetically modified chickpea seeds does not harm parasitoid wasps. PEST MANAGEMENT SCIENCE 2018; 74:2444-2449. [PMID: 29569394 DOI: 10.1002/ps.4919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 03/09/2018] [Accepted: 03/15/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Legumes have been genetically engineered to express α-amylase inhibitor 1 (αAI-1) from common bean in their seeds. Whereas the genetically modified (GM) seeds are immune to multiple bruchid pest species, the cosmopolitan bruchid Acanthoscelides obtectus is tolerant to αAI-1 and their larvae develop normally inside the seeds. Hymenopteran bruchid parasitoids, the most important natural enemies of bruchids, might thus be exposed to αAI-1 when attacking A. obtectus larvae developing inside GM seeds. Exposure might reduce parasitoid fitness, resulting in a decline in the natural control of A. obtectus, and thus promote the spread of this pest. We investigated the impact of the presence of αAI-1 in legume seeds on parasitoid fitness in tritrophic experiments with αAI-1 GM or non-GM chickpea seeds, A. obtectus, and three parasitoid species. Additionally, we investigated the exposure of parasitoids to αAI-1 using a fourth, highly sensitive parasitoid species. RESULTS Parasitoid fitness was not affected when A. obtectus was used in GM chickpea seeds as hosts, and this lack of effects was probably attributable to the fact that exposure of the parasitoids to αAI-1 was negligible. CONCLUSION We conclude that the release of GM chickpeas containing αAI-1 should not harm this important group of non-target insects. © 2018 Society of Chemical Industry.
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Affiliation(s)
- Christoph Lüthi
- Agroscope, Research Division Agroecology and Environment, Reckenholzstrasse 191, Zürich, Switzerland
| | - Fernando Álvarez-Alfageme
- Agroscope, Research Division Agroecology and Environment, Reckenholzstrasse 191, Zürich, Switzerland
| | - Jörg Romeis
- Agroscope, Research Division Agroecology and Environment, Reckenholzstrasse 191, Zürich, Switzerland
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Mathiron AGE, Pottier P, Goubault M. Let the most motivated win: resource value components affect contest outcome in a parasitoid wasp. Behav Ecol 2018. [DOI: 10.1093/beheco/ary084] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Anthony G E Mathiron
- Institut de Recherche sur la Biologie de l’Insecte, UMR 7261 CNRS - Université de Tours, Parc Grandmont, France
| | - Patrice Pottier
- Institut de Recherche sur la Biologie de l’Insecte, UMR 7261 CNRS - Université de Tours, Parc Grandmont, France
| | - Marlène Goubault
- Institut de Recherche sur la Biologie de l’Insecte, UMR 7261 CNRS - Université de Tours, Parc Grandmont, France
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Agbessenou A, Tounou AK, Dannon EA, Datinon B, Agboton C, Srinivasan R, Pittendrigh BR, Tamò M. Influence of Rearing Substrates and Nontarget Hosts on the Bionomics of the Tachinid Parasitoid Nemorilla maculosa (Diptera: Tachinidae). ENVIRONMENTAL ENTOMOLOGY 2018; 47:356-363. [PMID: 29462276 DOI: 10.1093/ee/nvy007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The tachinid Nemorilla maculosa Meigen (Diptera: Tachinidae) was introduced from Taiwan to Benin for evaluating its potential as a biocontrol candidate against the cowpea pest Maruca vitrata (Fabricius) (Lepidoptera: Crambidae). To optimize its rearing, we assessed the influence of M. vitrata larval age and rearing substrate-cowpea germinating grains and peabush leaves-on its life table parameters, while its host specificity was investigated with regard to nontarget effects. Parasitism rates were higher when older larvae (10- and 14-d old) were offered to females of N. maculosa compared to the younger (2-, 4-, and 6-d old) host larvae. Regardless of the rearing substrate, development time was longer for females than males, and females lived longer than males irrespective of the age of the host. Sex ratio did not vary significantly with host ages or rearing substrate. The average number of eggs laid by a female reared from M. vitrata larvae feeding on cowpea germinating grains or peabush leaves was 94.2 ± 4.38 and 71.9 ± 1.70 eggs, respectively. The host suitability of N. maculosa was assessed by testing four nontarget Lepidoptera species: Spodoptera littoralis Boisduval (Lepidoptera: Noctuidae), Sesamia calamistis Hampson (Lepidoptera: Noctuidae), Corcyra cephalonica (Stainton) (Lepidoptera: Pyralidae), and Eldana saccharina Walker (Lepidoptera: Pyralidae). Larvae of S. littoralis and C. cephalonica were successfully parasitized while N. maculosa did not develop in the larvae of E. saccharina and S. calamistis although they were parasitized. Despite the potential of N. maculosa as a biological control agent against the pod borer M. vitrata, more detailed nontarget studies, extending to other native Crambidae species, are needed before making decisions on field releases.
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Affiliation(s)
- Ayaovi Agbessenou
- International Institute of Tropical Agriculture (Benin Station), Cotonou, Benin
- Ecole Supérieure d'Agronomie, Université de Lomé, Lomé, Togo
| | | | | | - Benjamin Datinon
- International Institute of Tropical Agriculture (Benin Station), Cotonou, Benin
| | - Cyriaque Agboton
- International Institute of Tropical Agriculture (Benin Station), Cotonou, Benin
| | | | | | - Manuele Tamò
- International Institute of Tropical Agriculture (Benin Station), Cotonou, Benin
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Boulton RA, Collins LA, Shuker DM. Beyond sex allocation: the role of mating systems in sexual selection in parasitoid wasps. Biol Rev Camb Philos Soc 2015; 90:599-627. [PMID: 24981603 PMCID: PMC4409842 DOI: 10.1111/brv.12126] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 05/19/2014] [Accepted: 05/28/2014] [Indexed: 11/30/2022]
Abstract
Despite the diverse array of mating systems and life histories which characterise the parasitic Hymenoptera, sexual selection and sexual conflict in this taxon have been somewhat overlooked. For instance, parasitoid mating systems have typically been studied in terms of how mating structure affects sex allocation. In the past decade, however, some studies have sought to address sexual selection in the parasitoid wasps more explicitly and found that, despite the lack of obvious secondary sexual traits, sexual selection has the potential to shape a range of aspects of parasitoid reproductive behaviour and ecology. Moreover, various characteristics fundamental to the parasitoid way of life may provide innovative new ways to investigate different processes of sexual selection. The overall aim of this review therefore is to re-examine parasitoid biology with sexual selection in mind, for both parasitoid biologists and also researchers interested in sexual selection and the evolution of mating systems more generally. We will consider aspects of particular relevance that have already been well studied including local mating structure, sex allocation and sperm depletion. We go on to review what we already know about sexual selection in the parasitoid wasps and highlight areas which may prove fruitful for further investigation. In particular, sperm depletion and the costs of inbreeding under chromosomal sex determination provide novel opportunities for testing the role of direct and indirect benefits for the evolution of mate choice.
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Affiliation(s)
- Rebecca A Boulton
- Centre for Biological Diversity, School of Biology, University of St AndrewsDyers Brae, Greenside place, Fife KY16 9TH, U.K.
| | - Laura A Collins
- Centre for Biological Diversity, School of Biology, University of St AndrewsDyers Brae, Greenside place, Fife KY16 9TH, U.K.
| | - David M Shuker
- Centre for Biological Diversity, School of Biology, University of St AndrewsDyers Brae, Greenside place, Fife KY16 9TH, U.K.
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Chirault M, Lucas C, Goubault M, Chevrier C, Bressac C, Lécureuil C. A combined approach to heat stress effect on male fertility in Nasonia vitripennis: from the physiological consequences on spermatogenesis to the reproductive adjustment of females mated with stressed males. PLoS One 2015; 10:e0120656. [PMID: 25807005 PMCID: PMC4373853 DOI: 10.1371/journal.pone.0120656] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 02/05/2015] [Indexed: 11/20/2022] Open
Abstract
In recent years, several studies have shown a decline in reproductive success in males in both humans and wildlife. Research on male fertility has largely focused on vertebrates, although invertebrates constitute the vast majority of terrestrial biodiversity. The reduction of their reproductive capacities due to environmental stresses can have strong negative ecological impacts, and also dramatic consequences on world food production if it affects the reproductive success of biological control agents, such as parasitic wasps used to control crop pests. Here Nasonia vitripennis, a parasitic wasp of various fly species, was studied to test the effects of 24h-heat stress applied during the first pupal stage on male fertility. Results showed that only primary spermatocytes were present at the first pupal stage in all cysts of the testes. Heat stress caused a delay in spermatogenesis during development and a significant decrease in sperm stock at emergence. Females mated with these heat-stressed males showed a reduce sperm count stored in their spermatheca. Females did not appear to distinguish heat-stressed from control males and did not remate more frequently to compensate for the lack of sperm transferred. As a result, females mated with heat-stressed males produced a suboptimal lifetime offspring sex ratio compared to those mated with control males. This could further impact the population dynamics of this species. N. vitripennis appears to be an interesting biological model to study the mechanisms of subfertility and its consequence on female reproductive strategies and provides new research perspectives in both invertebrates and vertebrates.
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Affiliation(s)
- Marlène Chirault
- Institut de Recherche sur la Biologie de l’Insecte, UMR 7261, Université François-Rabelais / CNRS, UFR Sciences et Techniques, Parc Grandmont, Tours, France
| | - Christophe Lucas
- Institut de Recherche sur la Biologie de l’Insecte, UMR 7261, Université François-Rabelais / CNRS, UFR Sciences et Techniques, Parc Grandmont, Tours, France
| | - Marlène Goubault
- Institut de Recherche sur la Biologie de l’Insecte, UMR 7261, Université François-Rabelais / CNRS, UFR Sciences et Techniques, Parc Grandmont, Tours, France
| | - Claude Chevrier
- Institut de Recherche sur la Biologie de l’Insecte, UMR 7261, Université François-Rabelais / CNRS, UFR Sciences et Techniques, Parc Grandmont, Tours, France
| | - Christophe Bressac
- Institut de Recherche sur la Biologie de l’Insecte, UMR 7261, Université François-Rabelais / CNRS, UFR Sciences et Techniques, Parc Grandmont, Tours, France
| | - Charlotte Lécureuil
- Institut de Recherche sur la Biologie de l’Insecte, UMR 7261, Université François-Rabelais / CNRS, UFR Sciences et Techniques, Parc Grandmont, Tours, France
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Malfi RL, Davis SE, Roulston TH. Parasitoid fly induces manipulative grave-digging behaviour differentially across its bumblebee hosts. Anim Behav 2014. [DOI: 10.1016/j.anbehav.2014.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Male–male contests for mates, sexual size dimorphism, and sex ratio in a natural population of a solitary parasitoid. Behav Processes 2013; 100:1-8. [DOI: 10.1016/j.beproc.2013.07.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2013] [Revised: 06/24/2013] [Accepted: 07/05/2013] [Indexed: 11/22/2022]
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9
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Lüthi C, Álvarez-Alfageme F, Romeis J. Impact of αAI-1 expressed in genetically modified cowpea on Zabrotes subfasciatus (Coleoptera: Chrysomelidae) and its parasitoid, Dinarmus basalis (Hymenoptera: Pteromalidae). PLoS One 2013; 8:e67785. [PMID: 23840776 PMCID: PMC3695894 DOI: 10.1371/journal.pone.0067785] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 05/27/2013] [Indexed: 11/27/2022] Open
Abstract
Genetically modified (GM) cowpea seeds expressing αAI-1, an α-amylase inhibitor from the common bean, have been shown to be immune against several bruchid species. Effective control of such pests by growing GM cowpea could promote the spread of bruchid species that are αAI-1 tolerant. Consequently, the sustainability of bruchid pest control could be increased by combining GM seeds and hymenopteran parasitoids. However, there are concerns that αAI-1 could interfere with the biological control provided by parasitoids. Here, we assessed the impact of GM cowpea seeds expressing αAI-1 on the αAI-1-tolerant bruchid Zabrotes subfasciatus and its parasitoid Dinarmus basalis. αAI-1 in cowpea seeds did not increase resistance to Z. subfasciatus or affect the mortality rate of Z. subfasciatus larvae. Parasitism of Z. subfasciatus by D. basalis and fitness of D. basalis offspring were not affected by the presence of αAI-1. Thus, αAI-1-expressing cowpeas and parasitoids should be compatible for the control of bruchid pests.
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Affiliation(s)
- Christoph Lüthi
- Agroscope Reckenholz-Tänikon Research Station ART, Zürich, Switzerland
| | | | - Jörg Romeis
- Agroscope Reckenholz-Tänikon Research Station ART, Zürich, Switzerland
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Nguyen TM, Bressac C, Chevrier C. Heat stress affects male reproduction in a parasitoid wasp. JOURNAL OF INSECT PHYSIOLOGY 2013; 59:248-254. [PMID: 23262365 DOI: 10.1016/j.jinsphys.2012.12.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 12/06/2012] [Accepted: 12/07/2012] [Indexed: 06/01/2023]
Abstract
In insects, reproductive success and survival are affected by temperature. Reproduction is more sensitive than other physiological traits. While the effects of heat stress on females are well known, the effects on males are less clear. Hymenopteran parasitoids are valuable for studying the consequences of heat stress on male reproduction. In these species, through arrhenotoquous parthenogenesis, the sex ratio of the offspring is directly dependent on the sperm stock acquired by females during copulation. In the lab, heat temperature treatments (32-44°C) were applied for 3 days in the pupal stage of Anisopteromalus calandrae males, and development was completed at 30°C. Three different effects were observed depending on the temperature: mortality above 42°C, sterility of emerging males at 40°C, and sub-fertility at 38°C. This sub-fertility is characterized by a dramatic decrease in male sperm supplies, of up to 7% compared to control males. In the course of ageing, the sperm stock of sub-fertile males increases but never reaches the level of control males. Survival was significantly higher in control (30°C) males than those treated at 38°C. Male mating ability was similar whatever the treatment (control and 38°C), but females mated with 38°C-treated males stored 100 times less sperm on average than those mated with control males. The offspring sex ratio of females mated with 38°C-treated males was strongly male biased. The physiological mechanisms are as yet unknown. The relationship between temperature, sperm stock and sex ratio should be taken into account in the management of parasitoids for integrated pest management.
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Affiliation(s)
- Thanh Manh Nguyen
- Institut de Recherche sur la Biologie de l'Insecte, UMR CNRS 7261, Université de Tours, Parc de Grandmont, F-37200 Tours, France
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Zaugg I, Benrey B, Bacher S. Bottom-up and top-down effects influence bruchid beetle individual performance but not population densities in the field. PLoS One 2013; 8:e55317. [PMID: 23383151 PMCID: PMC3558490 DOI: 10.1371/journal.pone.0055317] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Accepted: 12/21/2012] [Indexed: 11/29/2022] Open
Abstract
Plant quality (bottom-up) and natural enemies (top-down) can influence the individual performance of herbivorous insects on their host plants, but few studies measured at the same time the influence on population densities in the field. We investigated if plant quality of different wild common bean populations, Phaseolus vulgaris L. (Fabaceae), affects the performance of the bean weevil, Acanthoscelides obtectus (Say) (Coleoptera: Bruchidae), and one of its enemies, the ectoparasitoid Dinarmus basalis (Rondani) (Hymenoptera: Pteromalidae), in controlled laboratory experiments. Additionally, we examined if parasitoids influence the beetles' development and if increased individual beetle and parasitoid fitness lead to higher field population densities. We show that bean quality and parasitoids affected individual bean weevil performance under laboratory and field conditions. In the presence of parasitoids, fewer and smaller beetles emerged. However, beetle and parasitoid performance were not correlated. Increased individual performance was not leading to higher population densities; we found no correlations between measured performance components and beetle field infestation levels or parasitism rates. We conclude that bottom-up or top-down effects measured at the individual level do not always translate into population effects; therefore it is important to discriminate between effects acting on individual insects and those acting on populations.
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Affiliation(s)
- Isabelle Zaugg
- Unit of Ecology & Evolution, Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Betty Benrey
- Institut de Biologie, University of Neuchâtel, Neuchâtel, Switzerland
| | - Sven Bacher
- Unit of Ecology & Evolution, Department of Biology, University of Fribourg, Fribourg, Switzerland
- * E-mail:
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12
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Ismail M, Vernon P, Hance T, Pierre JS, van Baaren J. What are the possible benefits of small size for energy-constrained ectotherms in cold stress conditions? OIKOS 2012. [DOI: 10.1111/j.1600-0706.2012.20582.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Lécureuil C, Rougière N, Nguyen TM, Bressac C, Chevrier C. [Parasitic wasps, a model for studying male subfertility]. Med Sci (Paris) 2012; 28:76-81. [PMID: 22289834 DOI: 10.1051/medsci/2012281020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Many studies have reported an increase in male reproductive disorders due to the environment. Despite their ecological importance invertebrates have been poorly studied; they are yet affected in the same way as vertebrates by changes in the environment. Different stresses made on parasitic wasps are able to induce a male subfertility. These insects are easy to rear in the laboratory, used to control insect pests, and have other benefits presented in this article. Parasitic wasps are good models for understanding the mechanisms inducing subfertility and may provide new areas for research in vertebrates.
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Affiliation(s)
- Charlotte Lécureuil
- Institut de Recherche sur la Biologie de l'insecte, UMR CNRS 6035, Université François Rabelais, parc de Grandmont, 37200 Tours, France.
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14
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Martel V, Darrouzet E, Boivin G. Phenotypic plasticity in the reproductive traits of a parasitoid. JOURNAL OF INSECT PHYSIOLOGY 2011; 57:682-687. [PMID: 21320506 DOI: 10.1016/j.jinsphys.2011.01.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Revised: 01/18/2011] [Accepted: 01/19/2011] [Indexed: 05/30/2023]
Abstract
Organisms show phenotypic plasticity--the capacity for a given genotype to express different phenotypes--in response to changes in the environment. Among the several factors that can cause phenotypic plasticity, nutritional constraints during development can affect the size of organisms and, consequently, affect most life-history traits, including reproductive traits. As their larvae are restricted by the amount of food contained in their host, parasitoids are a good model to study phenotypic plasticity related to size. The phenotypic plasticity of reproductive traits was investigated in the egg parasitoid Trichogramma euproctidis (Hymenoptera: Trichogrammatidae) by using host species of different sizes. Adult size, sperm storage organs (seminal vesicles and spermatheca), number of sperm stored and gamete size (sperm and oocyte) are all influenced by the host species; larger individuals have larger organs which contain more sperm, and both sperm and oocytes are correlated with adult size. However, while females become larger than males and mature larger oocytes in larger hosts, increase in sperm length stops after a given threshold.
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Affiliation(s)
- Véronique Martel
- Horticultural Research and Development Centre, Agriculture and Agri-Food Canada, 430 Boul. Gouin, St-Jean-sur-Richelieu, Québec J3B3E6, Canada.
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Wyckhuys KAG, Stone L, Desneux N, Hoelmer KA, Hopper KR, Heimpel GE. Parasitism of the soybean aphid, Aphis glycines by Binodoxys communis: the role of aphid defensive behaviour and parasitoid reproductive performance. BULLETIN OF ENTOMOLOGICAL RESEARCH 2008; 98:361-70. [PMID: 18294416 PMCID: PMC2670187 DOI: 10.1017/s000748530800566x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The Asian parasitoid, Binodoxys communis (Gahan) (Hymenoptera: Braconidae), is a candidate for release against the exotic soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), in North America. In this study, we examined preferences by B. communis for the different developmental stages of A. glycines and investigated consequences of these preferences for parasitoid fitness. We also determined to what extent aphid defensive behaviours mediate such preferences. We found that B. communis readily attacks and successfully develops in the different A. glycines developmental stages. Binodoxys communis development time gradually increased with aphid developmental stage, and wasps took longest to develop in alates. An average (+/-SE) of 54.01+/-0.08% of parasitized A. glycines alatoid nymphs transformed into winged adult aphids prior to mummification. No-choice assays showed a higher proportion of successful attacks for immature apterous A. glycines nymphs compared to adults and alatoid nymphs. Also, choice trials indicated avoidance and lower attack and oviposition of adults and alatoid nymphs. The different aphid stages exhibited a range of defensive behaviours, including body raising, kicking and body rotation. These defenses were employed most effectively by larger aphids. We discuss implications for the potential establishment, spread and biological control efficacy of A. glycines by B. communis in the event that it is released in North America.
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Affiliation(s)
- K A G Wyckhuys
- Horticulture Research Center, Universidad Jorge Tadeo Lozano, Chia (Cundinamarca), Colombia.
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Bressac C, Damiens D, Chevrier C. Sperm stock and mating of males in a parasitoid wasp. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2008; 310:160-6. [PMID: 17385700 DOI: 10.1002/jez.b.21168] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Hymenoptera are haplodiploid insects, consequently sex ratio depends on female's sperm management which itself arises from the reproductive capacity of neighbouring males. To study the influence of ageing on male reproductive potential, laboratory experiments were conducted on Dinarmus basalis (Hymenoptera, Pteromalidae) males, a tropical wasp in which sperm counts are known to constrain sex ratio. Two groups of virgin males were compared: 1-day and 30-days old. Parameters recorded were sperm quantity and viability in seminal vesicles, shape of testis, mating ability in both individual and competitive situations and sperm stored by females after male multiple mating. Older males had twice as much sperm as young males, but their reproductive capacities did not differ. They were able to copulate with 20 successive virgin females in a short period. Sperm stored in spermathecae decreased with female mating order. In competition, old and young males had the same access to females. The difference between old and young males was visible at the level of reproductive tract: young males have functional testis and old males have empty non-functional testis. Spermatozoa are kept viable in male seminal vesicles for long periods. In this species, the reproductive potential of males is not altered by ageing. At the population level this may represent an adaptation for maintaining continuous reserves of sperm at the disposal of females.
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Affiliation(s)
- Christophe Bressac
- Institut de Recherche sur la Biologie de l'Insecte, CNRS, UMR 6035, Université de Tours, Tours, France.
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Lacoume S, Bressac C, Chevrier C. Sperm production and mating potential of males after a cold shock on pupae of the parasitoid wasp Dinarmus basalis (Hymenoptera: Pteromalidae). JOURNAL OF INSECT PHYSIOLOGY 2007; 53:1008-15. [PMID: 17604049 DOI: 10.1016/j.jinsphys.2007.05.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Revised: 05/09/2007] [Accepted: 05/10/2007] [Indexed: 05/16/2023]
Abstract
For ectothermic species, temperature is a key environmental factor influencing several aspects of their physiology and ecology, acting particularly on reproduction. To measure the consequences of a severe thermal stress during development on male reproduction, a cold shock (1h at -18 degrees C) was tested on Dinarmus basalis pupae. D. basalis (Hymenoptera: Pteromalidae) is a parasitoid wasp in which sperm management in both male and female is of prime importance. After a cold shock, developmental success was reduced, with a quarter of cold-shocked males not emerging correctly. The stress effects were estimated at the level of sperm stock in seminal vesicles of males at different ages and on the ability of 2-day-old males to access females in single and multiple mating and in male-male competition. Cold-shocked males had a reduced sperm stock compared to control males and this difference persisted with age. The rate of sperm production was similar in both groups. The consequences of a cold shock on male reproductive ability were perceptible in multiple mating and male-male competition but not in single mating. Cold-shocked males were at a disadvantage, inseminating fewer females and copulating less frequently. Finally, male pupae of D. basalis were able to withstand severe temperature stresses and their reproductive functions were partially preserved.
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Affiliation(s)
- Sandrine Lacoume
- Institut de Recherche sur la Biologie de l'Insecte, UMR CNRS 6035, Université de Tours, 37200, Tours, France.
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