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Tadeo E, Rull J. Hybridization, Behavioral Patterns, and Pre- and Postzygotic Isolation Between Two Recently Derived Species of Walnut-Infesting Rhagoletis Fruit Flies in the Highlands of Mexico. NEOTROPICAL ENTOMOLOGY 2021; 50:505-514. [PMID: 33765250 DOI: 10.1007/s13744-021-00865-3] [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: 08/21/2020] [Accepted: 03/02/2021] [Indexed: 06/12/2023]
Abstract
Episodes of isolation and secondary contact among populations of insects of Nearctic origin during Pleistocene glacial/postglacial climatic cycles had a strong evolutionary influence on the diversity of flies in the genus Rhagoletis in mountainous areas of Mexico. As a series of experiments undertaken to gather support for phylogenetic hypotheses on the origin of three walnut-infesting species in the suavis group, we examined pre- and postzygotic isolation between Rhagoletis completa Cresson, 1929 and R. ramosae Hernández-Ortiz, 1985. Despite morphological, biological, and behavioral differences, these two species were found to be capable of hybridization. Mating experiments in large enclosures revealed asymmetric sexual isolation. There were notable differences in male sexual behavior. While R. ramosae males mated exclusively on host fruit, R. completa males used fruit and alternative mating locations. During fruit-guarding and male-male contests, R. completa and R. ramosae males adopted markedly different wing postures. R. completa females were more reluctant to copulate with heterospecific males than R. ramosae females. During no choice crosses in small enclosures, there was a reduction of egg hatch for the hybrid cross of R. completa males × R. ramosae females. Our results and previous studies on reproductive isolation between other species pairs in the suavis group support a clade in which R. ramosae, R. zoqui Bush, 1966, and R. completa are close relatives all still capable of hybridizing.
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Affiliation(s)
- Eduardo Tadeo
- Instituto de Neuroetología, Universidad Veracruzana, Veracruz, Mexico
| | - Juan Rull
- LIEMEN-División Control Biológico de Plagas, PROIMI Biotecnología-CONICET, Tucumán, Argentina.
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Mateos M, Martinez Montoya H, Lanzavecchia SB, Conte C, Guillén K, Morán-Aceves BM, Toledo J, Liedo P, Asimakis ED, Doudoumis V, Kyritsis GA, Papadopoulos NT, Augustinos AA, Segura DF, Tsiamis G. Wolbachia pipientis Associated With Tephritid Fruit Fly Pests: From Basic Research to Applications. Front Microbiol 2020; 11:1080. [PMID: 32582067 PMCID: PMC7283806 DOI: 10.3389/fmicb.2020.01080] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 04/30/2020] [Indexed: 12/19/2022] Open
Abstract
Members of the true fruit flies (family Tephritidae) are among the most serious agricultural pests worldwide, whose control and management demands large and costly international efforts. The need for cost-effective and environmentally friendly integrated pest management (IPM) has led to the development and implementation of autocidal control strategies. These approaches include the widely used sterile insect technique and the incompatible insect technique (IIT). IIT relies on maternally transmitted bacteria (namely Wolbachia) to cause a conditional sterility in crosses between released mass-reared Wolbachia-infected males and wild females, which are either uninfected or infected with a different Wolbachia strain (i.e., cytoplasmic incompatibility; CI). Herein, we review the current state of knowledge on Wolbachia-tephritid interactions including infection prevalence in wild populations, phenotypic consequences, and their impact on life history traits. Numerous pest tephritid species are reported to harbor Wolbachia infections, with a subset exhibiting high prevalence. The phenotypic effects of Wolbachia have been assessed in very few tephritid species, due in part to the difficulty of manipulating Wolbachia infection (removal or transinfection). Based on recent methodological advances (high-throughput DNA sequencing) and breakthroughs concerning the mechanistic basis of CI, we suggest research avenues that could accelerate generation of necessary knowledge for the potential use of Wolbachia-based IIT in area-wide integrated pest management (AW-IPM) strategies for the population control of tephritid pests.
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Affiliation(s)
- Mariana Mateos
- Departments of Ecology and Conservation Biology, and Wildlife and Fisheries Sciences, Texas A&M University, College Station, TX, United States
| | - Humberto Martinez Montoya
- Laboratorio de Genética y Genómica Comparativa, Unidad Académica Multidisciplinaria Reynosa Aztlan, Universidad Autónoma de Tamaulipas, Ciudad Victoria, Mexico
| | - Silvia B Lanzavecchia
- Instituto de Genética 'Ewald A. Favret' - GV IABIMO (INTA-CONICET) Hurlingham, Buenos Aires, Argentina
| | - Claudia Conte
- Instituto de Genética 'Ewald A. Favret' - GV IABIMO (INTA-CONICET) Hurlingham, Buenos Aires, Argentina
| | | | | | - Jorge Toledo
- El Colegio de la Frontera Sur, Tapachula, Mexico
| | - Pablo Liedo
- El Colegio de la Frontera Sur, Tapachula, Mexico
| | - Elias D Asimakis
- Department of Environmental Engineering, University of Patras, Agrinio, Greece
| | - Vangelis Doudoumis
- Department of Environmental Engineering, University of Patras, Agrinio, Greece
| | - Georgios A Kyritsis
- Laboratory of Entomology and Agricultural Zoology, Department of Agriculture Crop Production and Rural Environment, University of Thessaly, Larissa, Greece
| | - Nikos T Papadopoulos
- Laboratory of Entomology and Agricultural Zoology, Department of Agriculture Crop Production and Rural Environment, University of Thessaly, Larissa, Greece
| | - Antonios A Augustinos
- Department of Plant Protection, Institute of Industrial and Forage Crops, Hellenic Agricultural Organization - DEMETER, Patras, Greece
| | - Diego F Segura
- Instituto de Genética 'Ewald A. Favret' - GV IABIMO (INTA-CONICET) Hurlingham, Buenos Aires, Argentina
| | - George Tsiamis
- Department of Environmental Engineering, University of Patras, Agrinio, Greece
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Augustinos AA, Moraiti CA, Drosopoulou E, Kounatidis I, Mavragani-Tsipidou P, Bourtzis K, Papadopoulos NT. Old residents and new arrivals of Rhagoletis species in Europe. BULLETIN OF ENTOMOLOGICAL RESEARCH 2019; 109:701-712. [PMID: 30744707 DOI: 10.1017/s0007485319000063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The genus Rhagoletis (Diptera: Tephritidae) comprises more than 65 species distributed throughout Europe, Asia and America, including many species of high economic importance. Currently, there are three Rhagoletis species that infest fruits and nuts in Europe. The European cherry fruit fly, Rhagoletis cerasi (may have invaded Europe a long time ago from the Caucasian area of West Asia), and two invasive species (recently introduced from North America): the eastern American cherry fruit fly, R. cingulata, and the walnut husk fly, R. completa. The presence of different Rhagoletis species may enhance population dynamics and establish an unpredictable economic risk for several fruit and nut crops in Europe. Despite their excessive economic importance, little is known on population dynamics, genetics and symbiotic associations for making sound pest control decisions in terms of species-specific, environmental friendly pest control methods. To this end, the current paper (a) summarizes recently accumulated genetic and population data for the European Rhagoletis species and their association with the endosymbiont Wolbachia pipientis, and (b) explores the possibility of using the current knowledge for implementing the innovative biological control methods of sterile insect technique and incompatible insect technique.
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Affiliation(s)
- A A Augustinos
- Department of Environmental and Natural Resources Management, University of Patras, Agrinio, Greece
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, Vienna, Austria
| | - C A Moraiti
- Department of Agriculture, Crop Production and Rural Environment, University of Thessaly, N. Ionia (Volos), Magnesia, Greece
| | - E Drosopoulou
- Department of Genetics, Development and Molecular Biology, School of Biology, Faculty of Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - I Kounatidis
- Cell Biology, Development, and Genetics Laboratory, Department of Biochemistry, University of Oxford, South Park Road, Oxford OX1 3QU, UK
- Diamond Light Source, Harwell Science & Innovation Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - P Mavragani-Tsipidou
- Department of Genetics, Development and Molecular Biology, School of Biology, Faculty of Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - K Bourtzis
- Insect Pest Control Laboratory, Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, Vienna, Austria
| | - N T Papadopoulos
- Department of Agriculture, Crop Production and Rural Environment, University of Thessaly, N. Ionia (Volos), Magnesia, Greece
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Chin TA, Cáceres CE, Cristescu ME. The evolution of reproductive isolation in Daphnia. BMC Evol Biol 2019; 19:216. [PMID: 31775606 PMCID: PMC6880586 DOI: 10.1186/s12862-019-1542-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 11/15/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The process by which populations evolve to become new species involves the emergence of various reproductive isolating barriers (RIB). Despite major advancements in understanding this complex process, very little is known about the order in which RIBs evolve or their relative contribution to the total restriction of gene flow during various stages of speciation. This is mainly due to the difficulties of studying reproductive isolation during the early stages of species formation. This study examines ecological and non-ecological RIB within and between Daphnia pulex and Daphnia pulicaria, two recently diverged species that inhabit distinct habitats and exhibit an unusual level of intraspecific genetic subdivision. RESULTS We find that while ecological prezygotic barriers are close to completion, none of the non-ecological barriers can restrict gene flow between D. pulex and D. pulicaria completely when acting alone. Surprisingly, we also identified high levels of postzygotic reproductive isolation in 'conspecific' interpopulation crosses of D. pulex. CONCLUSIONS While the ecological prezygotic barriers are prevalent during the mature stages of speciation, non-ecological barriers likely dominated the early stages of speciation. This finding indicates the importance of studying the very early stages of speciation and suggests the contribution of postzygotic isolation in initiating the process of speciation.
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Affiliation(s)
- Tiffany A Chin
- Department of Biology, McGill University, 1205 ave Docteur Penfield, Montreal, Quebec, H3A 1B1, Canada.
| | - Carla E Cáceres
- School of Integrative Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Melania E Cristescu
- Department of Biology, McGill University, 1205 ave Docteur Penfield, Montreal, Quebec, H3A 1B1, Canada
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Rull J, Tadeo E, Lasa R, Rodríguez CL, Altuzar-Molina A, Aluja M. Experimental hybridization and reproductive isolation between two sympatric species of tephritid fruit flies in the Anastrepha fraterculus species group. INSECT SCIENCE 2018; 25:1045-1055. [PMID: 28586142 DOI: 10.1111/1744-7917.12489] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 04/18/2017] [Accepted: 05/02/2017] [Indexed: 06/07/2023]
Abstract
Among tephritid fruit flies, hybridization has been found to produce local adaptation and speciation, and in the case of pest species, induce behavioral and ecological alterations that can adversely impact efficient pest management. The fraterculus species group within Anastrepha (Diptera: Tephritidae), is a rapidly radiating aggregate, which includes cryptic species complexes, numerous sister species, and several pest species. Molecular studies have highlighted the possibility of introgression between A. fraterculus and A. obliqua. Reproductive isolation has been studied among morphotypes of the A. fraterculus species complex as a tool for species delimitation. Here we examined the existence and strength of prezygotic and postzygotic isolation between sympatric populations of two closely related species within the highly derived fraterculus group (A. fraterculus and A. obliqua), coexisting in nature. Although adults of both species showed a strong tendency for assortative mating, a small proportion of hybrid pairings in both directions were observed. We also observed asymmetric postzygotic isolation, with one hybrid cross displaying a strong reduction in fecundity and F1 egg fertility. Survival was greater for the progeny of homotypic and hybrid crosses in the maternal host. There was a marked female biased sex ratio distortion for both F1 hybrid adults. Hybridization between A. fraterculus and A. obliqua in nature may be difficult but possible; these two species display stronger reproductive isolation than all pairs of species previously examined in the A. fraterculus species complex. Asymmetric postzygotic isolation is suggestive of Wolbachia mediated cytoplasmic incompatibilities that may be exploited in area-wide pest management.
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Affiliation(s)
- Juan Rull
- PROIMI Biotecnología-CONICET, LIEMEN-División Control Biológico de Plagas, Tucumán, Argentina
| | - Eduardo Tadeo
- Red de Manejo Biorracional de Plagas y Vectores, Instituto de Ecología, A.C., Xalapa, Veracruz, México
| | - Rodrigo Lasa
- Red de Manejo Biorracional de Plagas y Vectores, Instituto de Ecología, A.C., Xalapa, Veracruz, México
| | - Christian L Rodríguez
- Red de Manejo Biorracional de Plagas y Vectores, Instituto de Ecología, A.C., Xalapa, Veracruz, México
| | - Alma Altuzar-Molina
- Red de Manejo Biorracional de Plagas y Vectores, Instituto de Ecología, A.C., Xalapa, Veracruz, México
| | - Martín Aluja
- Red de Manejo Biorracional de Plagas y Vectores, Instituto de Ecología, A.C., Xalapa, Veracruz, México
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Vanoye-Eligio V, Mora-Olivo A, Gaona-García G, Reyes-Zepeda F, Rocandio-Rodríguez M. Mexican Fruit Fly Populations in the Semi-Arid Highlands of the Sierra Madre Oriental in Northeastern Mexico. NEOTROPICAL ENTOMOLOGY 2017; 46:380-387. [PMID: 28054305 DOI: 10.1007/s13744-016-0478-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 12/11/2016] [Indexed: 06/06/2023]
Abstract
The Mexican fruit fly, Anastrepha ludens Loew (Diptera: Tephritidae), is one of the most important pests of citrus in Mexico. We report the results of an analysis of A. ludens populations that inhabit the semi-arid highlands of the Sierra Madre Oriental in northeastern Mexico. This study aimed to provide information on population fluctuation of A. ludens and how it relates to climate variables, as well as insights into habitat and native parasitoids. Population peaked in the period July-November when ripe fruits of the wild host, Casimiroa pubescens Ramírez, were available. No adults were captured the rest of the year, suggesting that high populations depend on the availability of wild host fruit. No significant relationships between population fluctuation and climatic variables were observed, except for minimum temperature. Fruit samples of citron (Citrus medica L.), pomegranate (Punica granatum L.), and C. pubescens were collected to determine degree of infestation. Infestation levels (pupae/g) ranged between 0.0006 for citron, 0.0047 for pomegranate, and 0.0240 for C. pubescens. A native parasitoid of Tephritidae, Doryctobracon crawfordii (Viereck) (Braconidae), was identified. Parasitism percentage was calculated at 12.5% on C. pubescens fruits. No parasitoids were observed on citron or pomegranate fruit samples. These results contribute to knowledge on behavior of A. ludens native to temperate environments where no commercial hosts are available. Further research on host expansion of this pest in light of scenarios of global climate change is suggested.
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Affiliation(s)
- V Vanoye-Eligio
- Instituto de Ecología Aplicada, Univ Autónoma de Tamaulipas, División del Golfo 356, Colonia Libertad, 87019, Cd. Victoria, Tamaulipas, Mexico.
| | - A Mora-Olivo
- Instituto de Ecología Aplicada, Univ Autónoma de Tamaulipas, División del Golfo 356, Colonia Libertad, 87019, Cd. Victoria, Tamaulipas, Mexico
| | - G Gaona-García
- Instituto de Ecología Aplicada, Univ Autónoma de Tamaulipas, División del Golfo 356, Colonia Libertad, 87019, Cd. Victoria, Tamaulipas, Mexico
| | - F Reyes-Zepeda
- Instituto de Ecología Aplicada, Univ Autónoma de Tamaulipas, División del Golfo 356, Colonia Libertad, 87019, Cd. Victoria, Tamaulipas, Mexico
| | - M Rocandio-Rodríguez
- Instituto de Ecología Aplicada, Univ Autónoma de Tamaulipas, División del Golfo 356, Colonia Libertad, 87019, Cd. Victoria, Tamaulipas, Mexico
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Scordato ESC, Symes LB, Mendelson TC, Safran RJ. The role of ecology in speciation by sexual selection: a systematic empirical review. J Hered 2016; 105 Suppl 1:782-94. [PMID: 25149254 DOI: 10.1093/jhered/esu037] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Theoretical and empirical research indicates that sexual selection interacts with the ecological context in which mate choice occurs, suggesting that sexual and natural selection act together during the evolution of premating reproductive isolation. However, the relative importance of natural and sexual selection to speciation remains poorly understood. Here, we applied a recent conceptual framework for examining interactions between mate choice divergence and ecological context to a review of the empirical literature on speciation by sexual selection. This framework defines two types of interactions between mate choice and ecology: internal interactions, wherein natural and sexual selection jointly influence divergence in sexual signal traits and preferences, and external interactions, wherein sexual selection alone acts on traits and preferences but ecological context shapes the transmission efficacy of sexual signals. The objectives of this synthesis were 3-fold: to summarize the traits, ecological factors, taxa, and geographic contexts involved in studies of mate choice divergence; to analyze patterns of association between these variables; and to identify the most common types of interactions between mate choice and ecological factors. Our analysis revealed that certain traits are consistently associated with certain ecological factors. Moreover, among studies that examined a divergent sexually selected trait and an ecological factor, internal interactions were more common than external interactions. Trait-preference associations may thus frequently be subject to both sexual and natural selection in cases of divergent mate choice. Our results highlight the importance of interactions between sexual selection and ecology in mate choice divergence and suggest areas for future research.
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Affiliation(s)
- Elizabeth S C Scordato
- From the Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309 (Scordato and Safran); the Department of Biological Sciences, Dartmouth College, Hanover, NH 03755 (Symes); and the Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD 21250 (Mendelson). Laurel B. Symes is now at the Department of Biological Sciences, University of Wisconsin, Milwaukee, WI 53201.
| | - Laurel B Symes
- From the Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309 (Scordato and Safran); the Department of Biological Sciences, Dartmouth College, Hanover, NH 03755 (Symes); and the Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD 21250 (Mendelson). Laurel B. Symes is now at the Department of Biological Sciences, University of Wisconsin, Milwaukee, WI 53201
| | - Tamra C Mendelson
- From the Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309 (Scordato and Safran); the Department of Biological Sciences, Dartmouth College, Hanover, NH 03755 (Symes); and the Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD 21250 (Mendelson). Laurel B. Symes is now at the Department of Biological Sciences, University of Wisconsin, Milwaukee, WI 53201
| | - Rebecca J Safran
- From the Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309 (Scordato and Safran); the Department of Biological Sciences, Dartmouth College, Hanover, NH 03755 (Symes); and the Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD 21250 (Mendelson). Laurel B. Symes is now at the Department of Biological Sciences, University of Wisconsin, Milwaukee, WI 53201
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Rull J, Aluja M, Tadeo E, Guillen L, Egan S, Glover M, Feder JL. Distribution, host plant affiliation, phenology, and phylogeny of walnut-infestingRhagoletisflies (Diptera: Tephritidae) in Mexico. Biol J Linn Soc Lond 2013. [DOI: 10.1111/bij.12157] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Juan Rull
- Instituto de Ecología A.C; Carretera Antigua a Coatepec no. 351 Col. El Haya Xalapa Veracruz 91070 Mexcio
| | - Martin Aluja
- Instituto de Ecología A.C; Carretera Antigua a Coatepec no. 351 Col. El Haya Xalapa Veracruz 91070 Mexcio
| | - Eduardo Tadeo
- Instituto de Ecología A.C; Carretera Antigua a Coatepec no. 351 Col. El Haya Xalapa Veracruz 91070 Mexcio
| | - Larissa Guillen
- Instituto de Ecología A.C; Carretera Antigua a Coatepec no. 351 Col. El Haya Xalapa Veracruz 91070 Mexcio
| | - Scott Egan
- Department of Biological Sciences; University of Notre Dame; Galvin Life Science Bld. Notre Dame IN 46530 USA
- Advanced Diagnostics and Therapeutics Initiative; University of Notre Dame; Notre Dame IN 46530 USA
| | - Mary Glover
- Department of Biological Sciences; University of Notre Dame; Galvin Life Science Bld. Notre Dame IN 46530 USA
| | - Jeffrey L. Feder
- Department of Biological Sciences; University of Notre Dame; Galvin Life Science Bld. Notre Dame IN 46530 USA
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Frey JE, Guillén L, Frey B, Samietz J, Rull J, Aluja M. Developing diagnostic SNP panels for the identification of true fruit flies (Diptera: Tephritidae) within the limits of COI-based species delimitation. BMC Evol Biol 2013; 13:106. [PMID: 23718854 PMCID: PMC3682933 DOI: 10.1186/1471-2148-13-106] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 05/15/2013] [Indexed: 11/14/2022] Open
Abstract
Background Rapid and reliable identification of quarantine pests is essential for plant inspection services to prevent introduction of invasive species. For insects, this may be a serious problem when dealing with morphologically similar cryptic species complexes and early developmental stages that lack distinctive characters useful for taxonomic identification. DNA based barcoding could solve many of these problems. The standard barcode fragment, an approx. 650 base pairs long sequence of the 5′end of the mitochondrial cytochrome oxidase I (COI), enables differentiation of a very wide range of arthropods. However, problems remain in some taxa, such as Tephritidae, where recent genetic differentiation among some of the described species hinders accurate molecular discrimination. Results In order to explore the full species discrimination potential of COI, we sequenced the barcoding region of the COI gene of a range of economically important Tephritid species and complemented these data with all GenBank and BOLD entries for the systematic group available as of January 2012. We explored the limits of species delimitation of this barcode fragment among 193 putative Tephritid species and established operational taxonomic units (OTUs), between which discrimination is reliably possible. Furthermore, to enable future development of rapid diagnostic assays based on this sequence information, we characterized all single nucleotide polymorphisms (SNPs) and established “near-minimal” sets of SNPs that differentiate among all included OTUs with at least three and four SNPs, respectively. Conclusions We found that although several species cannot be differentiated based on the genetic diversity observed in COI and hence form composite OTUs, 85% of all OTUs correspond to described species. Because our SNP panels are developed based on all currently available sequence information and rely on a minimal pairwise difference of three SNPs, they are highly reliable and hence represent an important resource for developing taxon-specific diagnostic assays. For selected cases, possible explanations that may cause composite OTUs are discussed.
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Affiliation(s)
- Juerg E Frey
- Federal Department of Economic Affairs FDEA, Agroscope Changins-Wädenswil Research Station ACW, Department of Plant Protection, Wädenswil, Switzerland.
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