Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 46
Filtrar
1.
Sci Rep ; 14(1): 25549, 2024 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-39461976

RESUMO

The Mediterranean fruit fly (Ceratitis capitata) is a globally invasive species and an economically significant pest of fruit crops. Understanding the evolutionary history and local climatic adaptation of this species is crucial for developing effective pest management strategies. We conducted a comprehensive investigation using whole genome sequencing to explore (i) the invasion history of C. capitata with an emphasis on historical admixture and (ii) local climatic adaptation across African, European, Central, and South American populations of C. capitata. Our results suggest a stepwise colonization of C. capitata in Europe and Latin America in which Mediterranean and Central American populations share an ancestral lineage. Conversely, South American invasion history is more complex, and our results partly suggest an old secondary invasion into South America from Europe or a colonization of South America directly from Africa, followed by admixture with an European lineage. Throughout its invasive range, C. capitata is challenged with diverse climatic regimes. A genome wide association study identified a relationship between allele frequency changes and specific bioclimatic variables. Notably, we observed a significant allele frequency shift related to adaptation to cold stress (BIO6), highlighting the species' ability to rapidly adapt to seasonal variations in colder climates.


Assuntos
Ceratitis capitata , Frequência do Gene , Espécies Introduzidas , Animais , Ceratitis capitata/genética , Ceratitis capitata/fisiologia , Clima , Estudo de Associação Genômica Ampla , Europa (Continente) , Adaptação Fisiológica/genética , Sequenciamento Completo do Genoma
2.
Bull Entomol Res ; 114(4): 503-513, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38817001

RESUMO

Two fruit fly (Diptera: Tephritidae) species of economic importance: Ceratitis rosa Karsch and Ceratitis quilicii De Meyer, Mwatawala & Virgilio are present in South Africa. The two species were considered as one species prior to 2016, but were subsequently separated. In this study, the distribution and abundance of the two species were quantified in seven provinces in South Africa through trapping with Enriched Ginger Oil as an attractant. Trapping was conducted over three seasons across two years (2020 and 2021): late summer, autumn-winter, and spring-early summer. Host ranges of the two species were investigated by fruit sampling in and outside of trapping sites. Ceratitis quilicii was more widely distributed than C. rosa with the latter being recorded in only three north-eastern provinces. There were geographical limits for both species with no records of them in Northern Cape Province. Catches of C. quilicii were higher in summer with average temperatures varying from 15 to 27°C while for C. rosa, catches remained low and consistent between seasons. Ceratitis quilicii catches decreased at lower rates than those of C. rosa at temperatures below 15°C. The two species were reared from 13 plant species from nine families. Four of these hosts were infested by both C. quilicii and C. rosa in the same province where they occurred. Preferred hosts of the two species belonged to the Myrtaceae family. The characterisation of the distribution, abundance and host ranges of these pests will provide a baseline for pest status determination and implementation of management actions.


Assuntos
Especificidade de Hospedeiro , Estações do Ano , Tephritidae , Animais , África do Sul , Tephritidae/fisiologia , Distribuição Animal
3.
Zookeys ; 1197: 127-136, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38651113

RESUMO

Identification of fruit fly larvae is difficult due to the limited morphological characteristics present. However, this is the stage at which fruit flies are intercepted at ports of entry through horticultural imports. Molecular tools are useful but are time-consuming and expensive compared to morphological identifications. This project aims to use available information from the literature and our own research to build a multi-entry identification key for thirteen tephritid species and species groups that are of economic concern for the European Union. Third-instar larvae were obtained from different regions and hosts. Thirteen species or representatives of species groups were obtained, including Ceratitis, Dacus, Bactrocera and Zeugodacus spp. The cephalopharyngeal skeletons were dissected out, cleared in a 10% NaOH solution, dehydrated and mounted in Euparal on glass slides. Images of at least 20 larvae/species were captured using a compound microscope fitted with a camera. Measurements were taken of the mounted mandibles and the number of tubules and their position in the anterior spiracles in relation to the cephalic skeleton were noted. Differences between morphometric parameters were tested via ANOVA and verified using discriminant function analysis. A matrix was compiled including nine characters for which significant inter-specific differentiation was preliminarily detected. The key was converted into a mobile application by LucID.

4.
PLoS One ; 19(4): e0300875, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38568989

RESUMO

Gut microbial communities are critical in determining the evolutive success of fruit fly phytophagous pests (Diptera, Tephritidae), facilitating their adaptation to suboptimal environmental conditions and to plant allelochemical defences. An important source of variation for the microbial diversity of fruit flies is represented by the crop on which larvae are feeding. However, a "crop effect" is not always the main driver of microbial patterns, and it is often observed in combination with other and less obvious processes. In this work, we aim at verifying if environmental stress and, by extension, changing environmental conditions, can promote microbial diversity in Zeugodacus cucurbitae (Coquillett), a cosmopolitan pest of cucurbit crops. With this objective, 16S rRNA metabarcoding was used to test differences in the microbial profiles of wild fly populations in a large experimental setup in Eastern Central Tanzania. The analysis of 2,973 unique ASV, which were assigned to 22 bacterial phyla, 221 families and 590 putative genera, show that microbial α diversity (as estimated by Abundance Coverage Estimator, Faith's Phylogenetic Diversity, Shannon-Weiner and the Inverse Simpson indexes) as well as ß microbial diversity (as estimated by Compositional Data analysis of ASVs and of aggregated genera) significantly change as the species gets closer to its altitudinal limits, in farms where pesticides and agrochemicals are used. Most importantly, the multivariate dispersion of microbial patterns is significantly higher in these stressful environmental conditions thus indicating that Anna Karenina effects contribute to the microbial diversity of Z. cucurbitae. The crop effect was comparably weaker and detected as non-consistent changes across the experimental sites. We speculate that the impressive adaptive potential of polyphagous fruit flies is, at least in part, related to the Anna Karenina principle, which promotes stochastic changes in the microbial diversity of fly populations exposed to suboptimal environmental conditions.


Assuntos
Microbiota , Tephritidae , Humanos , Animais , Tephritidae/genética , Tephritidae/microbiologia , Filogenia , RNA Ribossômico 16S/genética , Bactérias/genética , Microbiota/genética , Drosophila/genética
5.
Sci Rep ; 14(1): 2515, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291088

RESUMO

The species distributions migration poleward and into higher altitudes in a warming climate is especially concerning for economically important insect pest species, as their introduction can potentially occur in places previously considered unsuitable for year-round survival. We explore the expansion of the climatically suitable areas for a horticultural pest, the Mediterranean fruit fly (medfly) Ceratitis capitata (Diptera, Tephritidae), with an emphasis on Europe and California. We reviewed and refined a published CLIMEX model for C. capitata, taking into consideration new records in marginal locations, with a particular focus on Europe. To assess the model fit and to aid in interpreting the meaning of the new European distribution records, we used a time series climate dataset to explore the temporal patterns of climate suitability for C. capitata from 1970 to 2019. At selected bellwether sites in Europe, we found statistically significant trends in increasing climate suitability, as well as a substantial northward expansion in the modelled potential range. In California, we also found a significant trend of northward and altitudinal expansion of areas suitable for C. capitata establishment. These results provide further evidence of climate change impacts on species distributions and the need for innovative responses to increased invasion threats.


Assuntos
Ceratitis capitata , Tephritidae , Animais , Ceratitis capitata/fisiologia , Tephritidae/fisiologia , Europa (Continente) , Geografia , Mudança Climática
6.
BMC Ecol Evol ; 24(1): 9, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233768

RESUMO

BACKGROUND: Poor agricultural practices have drastically threatened insect pollinators' biodiversity. Little is known in Tanzania about how different agricultural practices affect pollinators' foraging behavior. This study investigated the effects of the agroecological zone, season, cucurbit species and management practices on visitation frequency, visitation rate and time spent on cucurbit flowers by five pollinator species viz. Apis mellifera, Eristalinus megacephalus, Mesembrius caffer, Paragus borbonicus and Toxomerus floralis. The experiment was designed as a 5 × 3 × 3 × 2 × 2 factorial arrangement in a Randomized Complete Block Design (RCBD) with four replications. GAMOUR-Agroecology was tested against conventional practices and untreated control. RESULTS: This study revealed significant effects of agroecological zone × season × cucurbit species × management practice on pollinators' visitation frequency (p = 0.007) and time spent on flowers (p = 0.005). Also, agroecological zone × season × cucurbit species × pollinator species significantly (p < 0.0001) affected pollinators' visitation frequency. Agroecological zones × season × cucurbit species × cucurbits management practices × pollinators significantly (p = 0.001) affected pollinators' visitation rate. Apis mellifera was the most frequent visitor in Cucurbita moschata plots treated with GAMOUR- Agroecology in the plateau zone, also, visited higher number of Cucumis sativus plots under GAMOUR-Agroecology practices in the mountainous zone during the October-November season. Furthermore, it has been found that pollinators spent much in cucurbit flowers on plots with GAMOUR-Agroecology practices and control. CONCLUSIONS: Pollinators' foraging behavior were enhanced by GAMOUR-Agroecology practices. Therefore, this study recommended that cucurbit growers should consider management practices that positively influence pollinator foraging activities for sustainable cucurbit production.


Assuntos
Cucurbita , Dípteros , Comportamento Alimentar , Polinização , Animais , Abelhas , Flores , Insetos , Tanzânia , Comportamento Animal
7.
Annu Rev Entomol ; 69: 355-373, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-37758223

RESUMO

Global trade in fresh fruit and vegetables, intensification of human mobility, and climate change facilitate fruit fly (Diptera: Tephritidae) invasions. Life-history traits, environmental stress response, dispersal stress, and novel genetic admixtures contribute to their establishment and spread. Tephritids are among the most frequently intercepted taxa at ports of entry. In some countries, supported by the rules-based trade framework, a remarkable amount of biosecurity effort is being arrayed against the range expansion of tephritids. Despite this effort, fruit flies continue to arrive in new jurisdictions, sometimes triggering expensive eradication responses. Surprisingly, scant attention has been paid to biosecurity in the recent discourse about new multilateral trade agreements. Much of the available literature on managing tephritid invasions is focused on a limited number of charismatic (historically high-profile) species, and the generality of many patterns remains speculative.


Assuntos
Drosophila , Características de História de Vida , Animais , Humanos , Mudança Climática , Nonoxinol
8.
J Econ Entomol ; 116(6): 1982-1989, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37852754

RESUMO

Ceratitis is an economically important genus of fruit flies that originated in Africa, has a wide host range, and causes serious economic losses due to its invasive damage. As a result, it is critical to identify them accurately and quickly in the world. Loop-mediated isothermal amplification (LAMP), as one of the representatives of isothermal amplification technology, has been widely used in the rapid nucleic acid detection of human pathogens and has shown its advantages in the identification of insect agricultural pests. In this study, using the mitochondrial cox1 and cob genes as target genes, the rapid molecular identification of the Ceratitis FARQ complex, C. cosyra, and C. capitata was realized based on LAMP. The experimental conditions optimization results showed that F3/B3:FIP/BIP = 1:8 was the optimal primer concentration ratio and 63 °C was the optimal reaction temperature. The sensitivity of the primers obtained in this study can reach up to 0.01 ng/µl DNA. A loop-mediated isothermal amplification identification technology system was established based on rapid, rough DNA extraction and visual detection of Ceratitis economically important fruit flies. The positive reaction system changed from pink to khaki by visual detection. The identification flow can be completed within 1 hour, including sample processing, DNA extraction, and LAMP visual detection.


Assuntos
Tephritidae , Humanos , Animais , Tephritidae/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Drosophila/genética , DNA , Sensibilidade e Especificidade
9.
Evol Appl ; 16(1): 48-61, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36699130

RESUMO

An increasing number of invasive fruit fly pests are colonizing new grounds. With this study, we aimed to uncover the invasion pathways of the oriental fruit fly, Bactrocera dorsalis into the islands of the Indian Ocean. By using genome-wide SNP data and a multipronged approach consisting of PCA, ancestry analysis, phylogenetic inference, and kinship networks, we were able to resolve two independent invasion pathways. A western invasion pathway involved the stepping-stone migration of B. dorsalis from the east African coast into the Comoros, along Mayotte and into Madagascar with a decreasing genetic diversity. The Mascarene islands (Reunion and Mauritius), on the contrary, were colonized directly from Asia and formed a distinct cluster. The low nucleotide diversity suggests that only a few genotypes invaded the Mascarenes. The presence of many long runs of homozygosity (ROH) in the introduced populations is indicative of population bottlenecks, with evidence of a more severe bottleneck for populations along the western migration pathway than on the Mascarene islands. More strict phytosanitary regulations are recommended in order to prevent the further spread of B. dorsalis.

10.
J Adv Res ; 53: 61-74, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36574947

RESUMO

INTRODUCTION: The oriental fruit fly Bactrocera dorsalis is one of the most destructive agricultural pests worldwide, with highly debated species delimitation, origin, and global spread routes. OBJECTIVES: Our study intended to (i) resolve the taxonomic uncertainties between B. dorsalis and B. carambolae, (ii) reveal the population structure and global invasion routes of B. dorsalis across Asia, Africa, and Oceania, and (iii) identify genomic regions that are responsible for the thermal adaptation of B. dorsalis. METHODS: Based on a high-quality chromosome-level reference genome assembly, we explored the population relationship using a genome-scale single nucleotide polymorphism dataset generated from the resequencing data of 487 B. dorsalis genomes and 25 B. carambolae genomes. Genome-wide association studies and silencing using RNA interference were used to identify and verify the candidate genes associated with extreme thermal stress. RESULTS: We showed that B. dorsalis originates from the Southern India region with three independent invasion and spread routes worldwide: (i) from Northern India to Northern Southeast Asia, then to Southern Southeast Asia; (ii) from Northern India to Northern Southeast Asian, then to China and Hawaii; and (iii) from Southern India toward the African mainland, then to Madagascar, which is mainly facilitated by human activities including trade and immigration. Twenty-seven genes were identified by a genome-wide association study to be associated with 11 temperature bioclimatic variables. The Cyp6a9 gene may enhance the thermal adaptation of B. dorsalis and thus boost its invasion, which tended to be upregulated at a hardening temperature of 38 °C. Functional verification using RNA interference silencing against Cyp6a9, led to the specific decrease in Cyp6a9 expression, reducing the survival rate of dsRNA-feeding larvae exposed to extreme thermal stress of 45 °C after heat hardening treatments in B. dorsalis. CONCLUSION: This study provides insights into the evolutionary history and genetic basis of temperature adaptation in B. dorsalis.


Assuntos
Tephritidae , Animais , Humanos , Tephritidae/genética , Estudo de Associação Genômica Ampla , Temperatura , Larva
11.
Microbiologyopen ; 11(4): e1307, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36031958

RESUMO

While contemporary changes in feeding preferences have been documented in phytophagous insects, the mechanisms behind these processes remain to be fully clarified. In this context, the insect gut microbiome plays a central role in adaptation to novel host plants. The cucurbit frugivorous fruit fly Zeugodacus cucurbitae (Diptera, Tephritidae) has occasionally been reported on "unconventional" host plants from different families, including Solanaceae. In this study, we focus on wild parental (F0 ) adults and semiwild first filial (F1 ) larvae of Z. cucurbitae from multiple sites in La Réunion and explore how the gut microbiome composition changes when this fly is feeding on a noncucurbit host (Solanum melongena). Our analyses show nonobvious gut microbiome responses following the F0 -F1 host shift and the importance of not just diet but also local effects, which heavily affected the diversity and composition of microbiomes. We identified the main bacterial genera responsible for differences between treatments. These data further stress the importance of a careful approach when drawing general conclusions based on laboratory populations or inadequately replicated field samples.


Assuntos
Cucurbitaceae , Microbioma Gastrointestinal , Solanum melongena , Tephritidae , Animais , Dieta
12.
GigaByte ; 2022: gigabyte59, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36824526

RESUMO

'MEMO: Monitoring of Exotic MOsquitoes in Belgium' is a sampling event dataset published by the Institute of Tropical Medicine (ITM) in Antwerp, Belgium. It forms part of the early detection of exotic mosquito species (EMS) along high-risk introduction routes in Belgium, where data are collected at defined points of entry (PoEs) using a standardised protocol. The MEMO dataset contains mosquito sampling counts performed between 2017 and 2020. MEMO+2020, an extension of the MEMO dataset, contains only Aedes albopictus mosquito trap counts performed in 2020. Here, we present these data published as a standardised Darwin Core archive, which includes, for each sampling event, an eventID, date, location and sampling protocol (in the event core); and an occurrenceID for each occurrence (tube), the number of collected individuals per tube, species status (present/absent), information on the identification and scientific name (in the occurrence extension).

13.
Mol Phylogenet Evol ; 161: 107160, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33794396

RESUMO

The Ceratitis FARQ complex (formerly FAR complex) includes four frugivorous tephritids, Ceratitis fasciventris, C. anonae, C. rosa and C. quilicii, the latter two causing important agricultural losses in Africa. Although FARQ species can be identified on the basis of subtle morphological differences, they cannot be resolved as monophyletic when trying phylogenetic tree reconstructions based on mitochondrial or nuclear gene fragments except for microsatellites. In this study, we used mitogenome and genome-wide SNPs to investigate the phylogenetic relationship within the complex as well as between all four Ceratitis subgenera. The analysis of 13 species supported the monophyly of the Ceratitis subgenera Ceratitis, Ceratalaspis, Pardalaspis, and recovered Pterandrus as paraphyletic but could not properly resolve species within the FARQ complex. Conversely, gene and species tree reconstructions based on 785,484 genome-wide SNPs could consistently resolve the FARQ taxa and provide insights into their phylogenetic relationships. Gene flow was detected by TreeMix analysis from C. quilicii to C. fasciventris, suggesting the existence of introgression events in the FARQ complex. Our results suggest that genome-wide SNPs represent a suitable tool for the molecular diagnosis of FARQ species and could possibly be used to develop rapid diagnostic methods or to trace the origins of intercepted samples.


Assuntos
Filogenia , Tephritidae , Animais , Núcleo Celular/genética , Fluxo Gênico , Genes Mitocondriais/genética , Repetições de Microssatélites , Tephritidae/genética
14.
Zootaxa ; 4920(1): zootaxa.4920.1.7, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33756679

RESUMO

A thorough knowledge of the presence and spatio-temporal distribution patterns of vector species are pivotal to assess the risk of mosquito-borne diseases in Europe. In 2018, a Culex larva was collected during routine monitoring activities to intercept exotic Aedes mosquito species in the port of Antwerp (Kallo, Belgium). The larva, collected from a pond in mid-September, was morphologically identified as Culex modestus, and this identification was subsequently confirmed by COI barcoding. It is the first confirmed record of this West Nile virus bridge vector in Belgium. The present study also demonstrates the value of DNA-based identification techniques to validate the presence of potential vector species.


Assuntos
Culex , Culicidae , Vírus do Nilo Ocidental , Animais , Bélgica , Culex/genética , DNA , Código de Barras de DNA Taxonômico , Mosquitos Vetores/genética , Vírus do Nilo Ocidental/genética
15.
Parasit Vectors ; 14(1): 179, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33766104

RESUMO

BACKGROUND: Aedes japonicus japonicus has expanded beyond its native range and has established in multiple European countries, including Belgium. In addition to the population located at Natoye, Belgium, locally established since 2002, specimens were recently collected along the Belgian border. The first objective of this study was therefore to investigate the origin of these new introductions, which were assumed to be related to the expansion of the nearby population in western Germany. Also, an intensive elimination campaign was undertaken at Natoye between 2012 and 2015, after which the species was declared to be eradicated. This species was re-detected in 2017, and thus the second objective was to investigate if these specimens resulted from a new introduction event and/or from a few undetected specimens that escaped the elimination campaign. METHODS: Population genetic variation at nad4 and seven microsatellite loci was surveyed in 224 and 68 specimens collected in Belgium and Germany, respectively. German samples were included as reference to investigate putative introduction source(s). At Natoye, 52 and 135 specimens were collected before and after the elimination campaign, respectively, to investigate temporal changes in the genetic composition and diversity. RESULTS: At Natoye, the genotypic microsatellite make-up showed a clear difference before and after the elimination campaign. Also, the population after 2017 displayed an increased allelic richness and number of private alleles, indicative of new introduction(s). However, the Natoye population present before the elimination programme is believed to have survived at low density. At the Belgian border, clustering results suggest a relation with the western German population. Whether the introduction(s) occur via passive human-mediated ground transport or, alternatively, by natural spread cannot be determined yet from the dataset. CONCLUSION: Further introductions within Belgium are expected to occur in the near future, especially along the eastern Belgian border, which is at the front of the invasion of Ae. japonicus towards the west. Our results also point to the complexity of controlling invasive species, since 4 years of intense control measures were found to be not completely successful at eliminating this exotic at Natoye.


Assuntos
Aedes/genética , Variação Genética , Genética Populacional , Espécies Introduzidas/tendências , Repetições de Microssatélites , Aedes/classificação , Aedes/fisiologia , Animais , Bélgica , Europa (Continente) , Genótipo , Humanos , Espécies Introduzidas/estatística & dados numéricos
16.
Pest Manag Sci ; 77(5): 2219-2230, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33345441

RESUMO

BACKGROUND: Attractant-based trapping is used in the establishment of pest-free areas and areas of low pest prevalence for fruit flies (Diptera: Tephritidae). Male lures are commonly used attractants in fruit fly trapping. In this study, the effects of male lure dispensers, traps and combinations of dispensers and traps on monitoring of two fruit fly pests, Ceratitis capitata (Wiedemann) and Bactrocera dorsalis (Hendel), were investigated in South Africa. RESULTS: In the male-lure-based trapping systems evaluated, trimedlure (TML) for C. capitata and methyl eugenol (ME) for B. dorsalis, the type of dispenser affected catches for both species. Higher catches of B. dorsalis males were recorded in bucket traps baited with a dispenser containing 15 g ME compared with traps baited with dispensers containing either 4 g ME or 2 g ME. Catches of C. capitata males were higher with dispensers containing TML than those with TML plus extender (Capilure®). The type of trap used with TML also influenced catches of C. capitata with higher numbers recorded in yellow Delta trap compared with the Sensus bucket trap. CONCLUSIONS: Dispensers with higher ME loadings are more effective for monitoring of B. dorsalis. The yellow Delta trap baited with TML (without extender) would be an effective monitoring system for C. capitata. Fruit fly prevalence levels as determined by specific trapping systems should be related to their efficiency in terms of catches of the target pests. © 2020 Society of Chemical Industry.


Assuntos
Ceratitis capitata , Tephritidae , Animais , Controle de Insetos , Masculino , Feromônios/farmacologia , África do Sul
17.
Zootaxa ; 4803(2): zootaxa.4803.2.1, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-33056016

RESUMO

The Afrotropical representatives of the hoverfly genus Phytomia Guérin-Méneville (Diptera) are revised. In total, 19 species are recognized of which three are new to science: Phytomia austeni sp. nov., P. memnon sp. nov., and P. pallida sp. nov. Phytomia neavei Bezzi is considered a junior synonym of P. kroeberi (Bezzi), P. noctilio Speiser a junior synonym of P. pubipennis Bezzi, and P. ephippium Bezzi a junior synonym of P. melas (Bezzi). Lectotypes are designated for the following species: Megaspis bulligera Austen, Megaspis erratica Bezzi, and Megaspis poensis Bezzi. In addition, unpublished lectotype designations are hereby formally published for the following species: Megaspis bullata Loew, Megaspis curta Loew, and Megaspis capito Loew. Phytomia curta (Loew) is considered a valid species, and differentiated from P. natalensis (Macquart). Phytomia fronto Loew is tentatively considered to belong to the genus Simoides Loew. The relationship between the different Phytomia species, as well as the relationship between Phytomia and Simoides, is briefly discussed based on morphological and DNA data.


Assuntos
Dípteros , Distribuição Animal , Animais
18.
Front Microbiol ; 11: 1890, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32849469

RESUMO

The family Tephritidae includes some of the most notorious insect pests of agricultural and horticultural crops in tropical and sub-tropical regions. Despite the interest in the study of their gut microbiome, our present knowledge is largely based on the analysis of laboratory strains. In this study, we present a first comparative analysis of the gut microbiome profiles of field populations of ten African and Mediterranean tephritid pests. For each species, third instar larvae were sampled from different locations and host fruits and compared using 16S rRNA amplicon sequencing and a multi-factorial sampling design. We observed considerable variation in gut microbiome diversity and composition both between and within fruit fly species. A "core" microbiome, shared across all targeted species, could only be identified at most at family level (Enterobacteriaceae). At genus level only a few bacterial genera (Klebsiella, Enterobacter, and Bacillus) were present in most, but not all, samples, with high variability in their relative abundance. Higher relative abundances were found for seven bacterial genera in five of the fruit fly species considered. These were Erwinia in Bactrocera oleae, Lactococcus in B. zonata, Providencia in Ceratitis flexuosa, Klebsiella, and Rahnella in C. podocarpi and Acetobacter and Serratia in C. rosa. With the possible exception of C. capitata and B. dorsalis (the two most polyphagous species considered) we could not detect obvious relationships between fruit fly dietary breadth and microbiome diversity or abundance patterns. Similarly, our results did not suggest straightforward differences between the microbiome profiles of species belonging to Ceratitis and the closely related Bactrocera/Zeugodacus. These results provide a first comparative analysis of the gut microbiomes of field populations of multiple economically relevant tephritids and provide base line information for future studies that will further investigate the possible functional role of the observed associations.

19.
J Econ Entomol ; 113(3): 1455-1470, 2020 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-32112108

RESUMO

The Mediterranean fruit fly, Ceratitis capitata (Weidemann), is one of the most economically important tephritid species worldwide. It has spread across six geographic regions as a result of successful invasions and continues to cause substantial losses to agricultural communities. Our study examined 1,864 flies originating from 150 localities, using mitochondrial DNA sequencing methods. We tested for population structure and revealed the genetic diversity for 1,592 specimens gathered from 144 wild fly collections from 46 countries representing the entire geographic range for this species. We also include in this study 272 Sterile Insect Technique (SIT) specimens from four SIT facilities. We recovered 202 haplotypes from the current sampling and updated previously published work to reveal a total of 231 haplotypes for this pest. These data show population structure at and below the regional level for these collections, shedding light on the current demographics for this species. We observed four common haplotypes, seen among 62% of the samples sequenced that have worldwide distribution. Three haplotypes were seen in SIT flies, with one seen as the predominant haplotype. Our work showed that two of the haplotypes were private to SIT flies, not present among wild fly collections. However, a third haplotype common among wild fly collections was also seen in one SIT facility but at a low frequency based on the current sampling. We provide guidance on the interpretation of these methods for the source estimation of current and future infestations.


Assuntos
Ceratitis capitata , Tephritidae , Animais , Ceratitis capitata/genética , DNA Mitocondrial/genética , Haplótipos , Filogeografia , Tephritidae/genética
20.
Genome ; 62(10): 677-687, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31283887

RESUMO

The hoverfly genus Eristalinus (Diptera, Syrphidae) contains many widespread pollinators. The majority of the species of Eristalinus occur in the Afrotropics and their molecular systematics still needs to be investigated. This study presents the first complete and annotated mitochondrial genomes for five species of Eristalinus. They were obtained by high-throughput sequencing of total genomic DNA. The total length of the mitogenomes varied between 15 757 and 16 245 base pairs. Gene composition, positions, and orientation were shared across species, and were identical to those observed for other Diptera. Phylogenetic analyses (maximum likelihood and Bayesian inference) based on the 13 protein coding and both rRNA genes suggested that the subgenus Eristalinus was paraphyletic with respect to the subgenus Eristalodes. An analysis of the phylogenetic informativeness of all protein coding and rRNA genes suggested that NADH dehydrogenase subunit 5 (nad5), cytochrome c oxidase subunit 1, nad4, nad2, cytochrome b, and 16S rRNA genes are the most promising mitochondrial molecular markers to result in supported phylogenetic hypotheses of the genus. In addition to the five complete mitogenomes currently available for hoverflies, the five mitogenomes published here will be useful for broader molecular phylogenetic analyses among hoverflies.


Assuntos
Dípteros/genética , Genoma Mitocondrial , Animais , Teorema de Bayes , Dípteros/classificação , Funções Verossimilhança , Filogenia , Especificidade da Espécie
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA