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1.
PLoS One ; 16(8): e0255582, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34388152

RESUMO

The braconid parasitoid Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae) is one of the most important natural enemies in classical biological control programs against tephritid fruit flies worldwide. In light of the spread of the invasive fruit fly species, Bactrocera dorsalis in Africa and beyond, there is a need to implement classical biological control. The current study aimed to determine temperature thresholds for D. longicaudata reared on B. dorsalis, using life cycle simulation modeling to guide informed parasitoid releases in Africa. Simulated parameters included thermal requirements, population growth parameters at different temperature requirements, suitable areas for the establishment, and the number of generations per year under projected climatic conditions. The lower thermal threshold for the development was estimated at 10.0°C, with a thermal constant (k) of 333.3-degree days, while the maximum temperature threshold was estimated at 33.69°C. Fecundity was highest at 25°C, with 177.3 eggs per female. Temperature significantly affected the population growth parameters of D. longicaudata, and the maximum value of the intrinsic rate of increase (rm) was 0.145 at 27°C. Results indicate that D. longicaudata could successfully establish in tropical and sub-tropical regions under current and future climatic conditions. However, a slight change in the suitable areas is expected by the year 2050 due to a slight and gradual rise in temperature. Our findings provide important information for further release of this parasitoid in Africa as well as designing pest management strategies to limit the spread and reduce the impact of fruit flies sustainably.


Assuntos
Simulação por Computador , Estágios do Ciclo de Vida , Controle Biológico de Vetores , Temperatura , Tephritidae/crescimento & desenvolvimento , Vespas/fisiologia , Animais , Fertilidade , Interações Hospedeiro-Parasita , Larva/crescimento & desenvolvimento , Larva/parasitologia , Tephritidae/parasitologia
2.
Sci Rep ; 11(1): 11410, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34075121

RESUMO

Bactrocera tryoni is a polyphagous fruit fly that is predicated to have continuous breeding in tropical and subtropical Australia as temperature and hosts are not limiting. Nevertheless, in both rainforest and tropical agricultural systems, the fly shows a distinct seasonal phenology pattern with an autumn decline and a spring emergence. Temperature based population models have limited predictive capacity for this species and so the driver(s) for the observed phenology patterns are unknown. Using a demographic approach, we studied the age-structure of B. tryoni populations in subtropical Australia in an agricultural system, with a focus on times of the year when marked changes in population abundance occur. We found that the age-structure of the population varied with season: summer and autumn populations were composed of mixed-age flies, while late-winter and early-spring populations were composed of old to very old individuals. When held at a constant temperature, the longevity of adult reference cohorts (obtained from field infested fruits) also showed strong seasonality; the adults of spring and early autumn populations were short-lived, while late autumn and late winter adults were long-lived. While still expressing in modified landscapes, the data strongly suggests that B. tryoni has an endogenous mechanism which would have allowed it to cope with changes in the breeding resources available in its endemic monsoonal rainforest habitat, when fruits would have been abundant in the late spring and summer (wet season), and rare or absent during late autumn and winter (dry season).


Assuntos
Tephritidae , Animais , Austrália , Ecossistema , Herbivoria , Longevidade , Estações do Ano , Temperatura , Tephritidae/crescimento & desenvolvimento , Tephritidae/metabolismo
3.
J Therm Biol ; 97: 102877, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33863442

RESUMO

The oriental fruit fly Bactrocera dorsalis (Diptera: Tephritidae) is a major pest of fruit and vegetable production systems on several continents. The pest has invaded many countries, causing considerable impact on fruit production systems and commercialization. In this study we determined the relationship between temperature and development, survival and reproductive parameters of B. dorsalis on an artificial diet under laboratory conditions under 7 constant temperatures (10, 15, 20, 25, 30, 33 and 35 °C) with 70 ± 10% relative humidity and a photoperiod of L12:D12. We validated the laboratory results with a full life table analysis under semi-natural conditions in a screenhouse. We used the Insect Life Cycle Modeling (ILCYM) software for all mathematical models and simulations applied to all life history parameters. Bactrocera dorsalis completed its development at temperatures ranging between 15 and 33 °C with the mean developmental time of egg, larva, and pupa ranging between 1.46 and 4.31 days, 7.14-25.67 days, and 7.18-31.50 respectively. The models predicted temperatures ranging between 20 and 30 °C as favorable for development and survival, and 20 to 25 °C for optimal fecundity of B. dorsalis. Life table parameters showed the highest gross reproductive rate (GRR), net reproductive rate (Ro), intrinsic rate of increase (rm), and finite rate of increase (λ) between 25 and 31 ᵒC while generation time (T) and doubling time (Dt) were low at this interval. The effects of future climate change on B. dorsalis life history parameters were further investigated and the outcome from this study will help in the management of B. dorsalis in different agroecologies in the context of ongoing climate change.


Assuntos
Modelos Biológicos , Temperatura , Tephritidae , Animais , Feminino , Masculino , Reprodução , Estações do Ano , Tephritidae/crescimento & desenvolvimento , Tephritidae/fisiologia
4.
Bull Entomol Res ; 111(5): 560-567, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33814029

RESUMO

Anastrepha fraterculus (Diptera: Tephritidae) is a major barrier to fruit production and exportation. In Brazil, the native parasitoid Aganaspis pelleranoi (Hymenoptera: Figitidae) and the exotic parasitoid Diachasmimorpha longicaudata (Hymenoptera, Braconidae) stand out as biological control agents. Knowledge of the factors that affect interactions among parasitoids, A. fraterculus, and host fruits may enhance the use of these agents in biological control programmes. This study evaluated the chemotaxis and parasitism of A. pelleranoi and D. longicaudata females reared on A. fraterculus larvae and kept on an artificial diet, red guava (Psidium guajava) or apple (Malus domestica). Females of both parasitoid species that emerged from larvae raised on artificial diet, guava or apple, were tested to Y olfactometer choice tests. In the parasitism tests, both parasitoid species were made to choose between A. fraterculus larvae brushed with water, apple pulp or guava pulp. D. longicaudata females from artificial diet (control) did not distinguish between fruit odours; however, females of D. longicaudata from larvae kept in apple or guava directed to the odours of their original fruit. The greatest parasitism for D. longicaudata occurred in the units that contained the pulp in which the larvae grew. A. pelleranoi from artificial diet preferred guava odours, including the females kept in apple. Similar results were observed in the parasitism bioassays. Our results found that A. fraterculus larval feeding influenced search behaviour and parasitism of D. longicaudata, whereas A. pelleranoi rearing experience did not affect its host choices.


Assuntos
Quimiotaxia , Tephritidae/fisiologia , Tephritidae/parasitologia , Vespas/fisiologia , Animais , Agentes de Controle Biológico , Dieta , Feminino , Frutas , Interações Hospedeiro-Parasita , Larva/fisiologia , Malus , Psidium , Tephritidae/crescimento & desenvolvimento
5.
PLoS One ; 16(4): e0250731, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33901258

RESUMO

Lower elevations are generally thought to contain a greater abundance and diversity of insect communities and their natural enemies than higher elevations. It is less clear, however, how changes in seasons influence this pattern. We conducted a 2-year study (2013‒2014) in guava orchards located in a tropical Andean forest of Peru to investigate differences in fruit flies (Diptera: Tephritidae) and their parasitoid communities at two elevations and over two seasons. Fruit fly traps were installed, monitored, and guava fruits were sampled from eight orchards at low (800-950 m above sea level) and high (1,700-1,900 m above sea level) elevations and during the dry and rainy seasons. At each orchard, adult fruit fly trap captures and emergence of fruit flies and their parasitoids from guava fruit were quantified to determine their abundance and species composition. There was a greater abundance and species richness of fruit flies captured in traps at lower elevations, as well as higher abundance and species evenness of fruit flies that emerged from fruit, indicating that lower elevations are associated with larger fruit fly populations. The abundance, species richness and diversity of parasitoids were also greater at lower elevations. Consequently, guava fruit infestation and fruit fly parasitism rates were also greater at lower elevations. Seasonality also influenced fruit fly populations with a greater number of flies emerging from guava fruit and more fruit infested in the rainy season. However, seasonality had no effect on parasitoid population parameters or rate of parasitism, nor did it interact with elevation as an influence of populations of fruit flies or their parasitoids in guava orchards. This study highlights the importance of examining both elevation and seasonality for a better understanding of the population dynamics of fruit flies and their parasitoids in tropical agroecosystems.


Assuntos
Psidium/parasitologia , Tephritidae/fisiologia , Altitude , Animais , Florestas , Frutas/parasitologia , Himenópteros/fisiologia , Larva/fisiologia , Peru , Dinâmica Populacional , Psidium/crescimento & desenvolvimento , Estações do Ano , Tephritidae/crescimento & desenvolvimento
6.
Artigo em Inglês | MEDLINE | ID: mdl-33773478

RESUMO

The Chinese citrus fruit fly, Bactrocera minax (Enderlein), a devastating pest in citrus, has an obligatory diapause at the pupal stage. Although the physiology of obligatory diapause has been well described, the molecular mechanisms underlying the process remain unknow. Here we investigated the molecular mechanisms of obligatory diapause induction in B. minax using high-throughput RNA-Seq data from second-instar larva (2L), third-instar larva (3L) and pupa (P) stages. A total of 116,402 unigenes were obtained, of which 54,781 unigenes were successfully annotated in public databases, and the differentially expressed genes in the 3L vs 2L, P vs 2L, and P vs 3L comparisons were identified. The cluster co-expression patterns of the differentially expressed genes revealed that significantly differentially-expressed genes in the pupal stage were predicted to be related to diapause induction. All differentially expressed genes were investigated by GO functional and KEGG pathway analysis, and the results showed that genes involved in processes such as 20-hydroxyecdysone (20E) biosynthesis, cell cycle and metabolic pathways are likely related to obligatory diapause induction in B. minax. These results provide important information on the transcriptome of the Chinese citrus fruit fly that can be used for further functional studies as well as contributing to our understanding of the molecular basis of obligatory diapause induction and suggesting potential molecular targets for the control of this pest.


Assuntos
Diapausa de Inseto , Tephritidae/crescimento & desenvolvimento , Tephritidae/genética , Animais , Genômica , Larva/genética , Larva/crescimento & desenvolvimento , Pupa/genética , Pupa/crescimento & desenvolvimento , Transcriptoma
7.
J Econ Entomol ; 114(2): 947-958, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33537732

RESUMO

We used transcriptome analysis to research ovary development in Bactrocera dorsalis (Hendel). The ovary transcriptome of B. dorsalis yielded 66,463,710 clean reads that were assembled into 23,822 unigenes. After aligning to the Nr database in NCBI, 15,473 (64.95%) of the unigenes were matched to identified proteins. As determined by BLAST search, 11,043 (46.36%), 6,102 (25.61%), and 12,603 (52.90%) unigenes were each allocated to clusters via gene ontology, orthologous groups, and SwissProt, respectively. The Kyoto encyclopedia database of genes and genomes (KEGG) was further used to annotate these sequences, and 11,068 unigenes were mapped to 255 known pathways. Afterward, the genes that were possibly involved in oogenesis and ovary development were obtained from the transcriptome data and analyzed. Interestingly, seven ovary-specific genes were identified, including a Nanos gene that is involved in maintaining the primordial germ cells in many insects. Therefore, we further focused on the function of the BdNanos gene, and the gene was injected into B. dorsalis. As expected, the knocking down of Nanos gene expression led to significant inhibition of ovary development, suggesting an important role of this gene in the reproductive process of B. dorsalis. In summary, the present study provides an important reference for identifying the molecular mechanisms of oogenesis and ovary development in B. dorsalis. The BdNanos gene is crucial for ovary development in B. dorsalis and is therefore a potential new pest control target.


Assuntos
Proteínas de Insetos , Ovário/crescimento & desenvolvimento , Tephritidae , Animais , Feminino , Perfilação da Expressão Gênica , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Tephritidae/genética , Tephritidae/crescimento & desenvolvimento , Transcriptoma
8.
Insect Mol Biol ; 30(2): 176-187, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33280175

RESUMO

Larvae of the goldenrod gall fly, Eurosta solidaginis, rely on a freeze tolerance strategy to survive the sub-zero temperatures of Canadian winter. Critical to their survival is the accumulation of polyol cryoprotectants and global metabolic rate depression, both of which require the regulation of glycolysis and reorganization of carbohydrate metabolism. This study explored the role that pyruvate kinase (PK) regulation plays in this metabolic reorganization. PK was purified from control (5 °C-acclimated) and frozen (-15 °C-acclimated) larvae and enzyme kinetic properties, structural stability, and post-translational modifications were examined in both enzyme forms. The Km phosphoenolpyruvate (PEP) of frozen PK was 20% higher than that of control PK, whereas the Vmax of frozen PK was up to 50% lower than that of control PK at the lowest assay temperature, suggesting inhibition of the enzyme during the winter. Additionally, the activity and substrate affinity of both forms of PK decreased significantly at low assay temperatures, and both forms were regulated allosterically by a number of metabolites. Pro-Q™ Diamond phosphoprotein staining and immunoblotting experiments demonstrated significantly higher threonine phosphorylation of PK from frozen animals while acetylation and methylation levels remained constant. Together, these results indicate that PK exists in two structurally distinct forms in E. solidaginis. In response to conditions mimicking the transition to winter, PK appears to be regulated to support metabolic rate depression, the accumulation of polyol cryoprotectants, and the need for extended periods of anaerobic carbohydrate metabolism to allow the animal to survive whole-body freezing.


Assuntos
Piruvato Quinase/química , Piruvato Quinase/metabolismo , Tephritidae/enzimologia , Aclimatação , Animais , Temperatura Baixa , Congelamento , Larva/enzimologia , Fosforilação/fisiologia , Tephritidae/crescimento & desenvolvimento , Tephritidae/metabolismo
9.
Insect Sci ; 28(5): 1326-1337, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32856386

RESUMO

Cuticular proteins (CPs) are critical components of the insect cuticle and play important roles in maintaining normal insect development and defense against various environmental stresses. The oriental fruit fly (Bactrocera dorsalis) is one of the most destructive pests worldwide, and its eight CPs analogous to peritrophin 3 (BdCPAP3) family genes have been identified in our previous study. In the present study, we further explored the possible roles of CPAP3 genes in B. dorsalis development. Each sequence of BdCPAP3 genes contained three conserved ChtBD2 (chitin-binding) domains. Spatial and temporal expression patterns revealed that the four BdCPAP3 genes (BdCPAP3-A1, B, E, and E2) might play important roles in larval pupariation of B. dorsalis. Moreover, treatment with a juvenile hormone analog (methoprene) significantly restricted expression of these four CPAP3 genes, whereas treatment with 20-hydroxy-ecdysone induced expression. The RNA interference (RNAi) results revealed that down-regulated CPAP3 genes led to significant delay of pupariation, and injection of dsBdCPAP3-E into 5-d-old B. dorsalis larvae caused approximately 40% mortality. Interestingly, we also confirmed that BdCPAP3-D2 was involved in B. dorsalis ovarian development. This study showed that some specific CPAP3 genes had crucial roles in B. dorsalis development, and these CP genes could be used as potential targets to control this pest via RNAi.


Assuntos
Proteínas de Insetos , Glicoproteínas de Membrana , Ovário/crescimento & desenvolvimento , Tephritidae , Animais , Feminino , Técnicas de Silenciamento de Genes , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Larva/crescimento & desenvolvimento , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Interferência de RNA , Tephritidae/genética , Tephritidae/crescimento & desenvolvimento
10.
Insect Sci ; 28(2): 363-376, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32091660

RESUMO

Fruit flies usually harbor diverse communities of bacteria in their digestive systems, which are known to play a significant role in their fitness. However, little information is available on Zeugodacus tau, a polyphagous pest worldwide. This study reports the first extensive analysis of bacterial communities in different life stages and their effect on the development and reproduction of laboratory-reared Z. tau. Cultured bacteria were identified using the conventional method, and all bacteria were identified by high-throughput technologies (16S ribosomal RNA gene sequencing of V3-V4 region). A total of six bacterial phyla were identified in larvae, pupae, and male and female adult flies, which were distributed into 14 classes, 32 orders, 58 families and 96 genera. Proteobacteria was the most represented phylum in all the stages except larvae. Enterobacter, Klebsiella, Providencia, and Pseudomonas were identified by conventional and next-generation sequencing analysis in both male and female adult flies, and Enterobacter was found to be the main genus. After being fed with antibiotics from the first instar larvae, bacterial diversity changed markedly in the adult stage. Untreated flies laid eggs and needed 20 days before oviposition while the treated flies showed ovary development inhibited and were not able to lay eggs, probably due to the alteration of the microbiota. These findings provide the cornerstone for unexplored research on bacterial function in Z. tau, which will help to develop an environmentally friendly management technique for this kind of harmful insect.


Assuntos
Bactérias/isolamento & purificação , Microbiota , Tephritidae/microbiologia , Tephritidae/fisiologia , Animais , Bactérias/classificação , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Larva/crescimento & desenvolvimento , Larva/microbiologia , Masculino , Óvulo/crescimento & desenvolvimento , Óvulo/microbiologia , Pupa/crescimento & desenvolvimento , Pupa/microbiologia , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Reprodução , Tephritidae/crescimento & desenvolvimento
11.
Insect Sci ; 28(1): 261-270, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32096585

RESUMO

Fruit flies are considered economically important insects due to some species being agricultural pests. However, morphological identification of fruit fly adults and larvae can be difficult requiring a high level of taxonomic expertise, with misidentifications causing problematic false-positive/negative results. While destructive molecular techniques can assist with the identification process, these often cannot be applied where it is mandatory to retain a voucher reference specimen. In this work, we non-destructively (and partial-destructively) processed larvae and adults mostly belonging to the species Dirioxa pornia (Walker, 1849), of the poorly studied nonpest fruit fly tribe Acanthonevrini (Tephritidae) from Australia, to enable molecular identifications whilst retaining morphological vouchers. By retaining the morphological features of specimens, we confirmed useful characters for genus/species-level identification, contributing to improved accuracy for future diagnostics using both molecular and morphological approaches. We provide DNA barcode information for three species of Acanthonevrini known from Australia, which prior to our study was only available for a single species, D. pornia. Our specimen examinations provide new distribution records for three nonpest species: Acanthonevroides variegatus Permkam and Hancock, 1995 in South Australia, Acanthonevroides basalis (Walker, 1853) and D. pornia in Victoria, Australia; as well as new host plant records for D. pornia, from kangaroo apple, apricot and loquat.


Assuntos
Código de Barras de DNA Taxonômico , Controle de Insetos/métodos , Tephritidae/anatomia & histologia , Tephritidae/genética , Distribuição Animal , Animais , Austrália , Complexo IV da Cadeia de Transporte de Elétrons/análise , Proteínas de Insetos/análise , Larva/anatomia & histologia , Larva/genética , Larva/crescimento & desenvolvimento , Tephritidae/crescimento & desenvolvimento
12.
Insect Sci ; 28(1): 153-164, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31904897

RESUMO

We estimated thermal developmental thresholds (T0 ) and degree-day (DD) constants for the immature stages of two tephritid pests, Bactrocera zonata (Saunders) and Ceratitis capitata (Weidenmann). Males of both species were trapped in an Egyptian guava orchard during the fruiting seasons of 2016 and 2017 and trap catches were compared with peak flights predicted by the DD model based on local weather data. Ceratitis capitata had faster development than B. zonata at 20 and 25 °C, but their overall developmental rate was similar at 30 and 35 °C. The thermal threshold of development (T0 ) of B. zonata was higher than that of C. capitata, indicating greater sensitivity to cold. Although 35 °C yielded the fastest development of both species, survival was higher at 30 °C, with B. zonata experiencing a slight advantage, suggesting better tropical adaptation. Immature development of B. zonata and C. capitata was estimated to require 338 and 373 d, respectively, and 616 and 424 DD for a complete generation. Trap catches over both seasons showed good correspondence to peaks of fly activity predicted by the DD models; deviations from expectation ranged from 0 to 7 d for both fly species. Both species had four overlapping generations per season, with B. zonata abundance peaking in the first generation in both years, but only in 2016 for C. capitata. The models predict about eight and 12 generations per year in northeast Egypt for B. zonata and C. capitata, respectively. These models should be useful for timing pest control measures to coincide with periods of peak fly activity in fruit orchards.


Assuntos
Aclimatação , Tephritidae/crescimento & desenvolvimento , Animais , Ceratitis capitata/crescimento & desenvolvimento , Egito , Controle de Insetos , Masculino , Modelos Biológicos , Estações do Ano , Especificidade da Espécie , Temperatura
13.
Bull Entomol Res ; 111(2): 210-216, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32967739

RESUMO

For purposes of mass-rearing fruit flies, nutrient intake through artificial diets is a challenge, artificial food content and processing should promote sufficient absorption and availability to ensure fly fitness. Bulking agents play an essential role in creating a quality diet, but its physical characteristics, such as particle size, may establish a better microenvironment for feeding and development. Currently, there is a lack of information about protein metabolism in mass-reared fruit flies. Therefore, we evaluated whether the particle size of the bulking agent affects the absorption and excretion of the proteins, as well as their effect on the life-history traits of Anastrepha obliqua. We determined the protein content of hemolymph and feces, as well as the presence of nitrogen end-products as indicators of their level of absorption in a diet elaborated with coarse and fine corn cob particles as a bulking agent. The bromatological composition showed that coarse particles increased the bioavailability and content of crude, digestible, and soluble protein for the diet and hemolymph protein of larvae alike. We found an inverse relationship between the protein content of the hemolymph and feces of the larvae. Ammonium was determined to be a product of the catabolism of proteins. Also, A. obliqua improved its development (yield and pupal weight) and fitness (adult emergence and flight ability) when larvae were reared on a coarse particle diet. In conclusion, a diet elaborated with a coarse bulking agent features increased protein bioavailability and nutritional quality, which, in turn, increases the life-history traits of A. obliqua.


Assuntos
Dieta , Estado Nutricional , Tephritidae , Animais , Sangue/metabolismo , Fezes/química , Larva/crescimento & desenvolvimento , Estado Nutricional/fisiologia , Proteínas/metabolismo , Pupa/crescimento & desenvolvimento , Tephritidae/crescimento & desenvolvimento , Tephritidae/metabolismo , Tephritidae/fisiologia , Ácido Úrico/metabolismo
14.
Bull Entomol Res ; 111(2): 238-245, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32967744

RESUMO

With the purpose of broadening knowledge on the evolution of life history strategies and behaviour of fruit flies within the tribe Carpomyini, the natural history and mating behaviour of the poorly known species Rhagoletotrypeta pastranai Aczél, are described for the first time. Larvae of R. pastranai were recovered from infested Celtis tala Gillies ex Planch and Celtis iguanaea (Jacq.) Sarg. during a 2-month fruiting period. Adults emerged from the recovered pupae after an average of 144.9 ± 3.9 days for females and 143.2 ± 3.38 days for males, suggesting that most individuals became dormant. Results of a variable winter length study suggested that environmental factors other than winter length may regulate dormancy/diapause duration in this subtropical species. Under laboratory conditions, R. pastranai adults lived an average of 51.13 ± 3.06 days in case of females and 48.08 ± 3.76 days in case of males, and required 5-15 days to reach sexual maturity. Behavioural observations under confinement revealed scarce sexual activity but sufficed to determine that, as in other members of the tribe Carpomyini, R. pastranai exhibits a male resource defence mating system. We discuss our findings emphasizing the importance of documenting the natural history and behaviour of unknown species of family Tephritidae and additionally, we highlight the necessity of future research to understand factors regulating dormancy/diapause and the evolution of life history strategies and sexual behaviour of subtropical species.


Assuntos
Tephritidae/fisiologia , Animais , Evolução Biológica , Diapausa , Larva/crescimento & desenvolvimento , Larva/fisiologia , Traços de História de Vida , Masculino , Pupa/crescimento & desenvolvimento , Pupa/fisiologia , Reprodução , Estações do Ano , Comportamento Sexual Animal , Tephritidae/crescimento & desenvolvimento
15.
PLoS One ; 15(12): e0244493, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382763

RESUMO

The Chinese citrus fly, Bactrocera minax, is a notorious univoltine pest that causes damage to citrus. B. minax enters obligatory pupal diapause in each generation to resist harsh environmental conditions in winter. Despite the enormous efforts that have been made in the past decade, the understanding of pupal diapause of B. minax is currently still fragmentary. In this study, the 20-hydroxyecdysone solution and ethanol solvent was injected into newly-formed pupae to obtain non-diapause- (ND) and diapause-destined (D) pupae, respectively, and a comparative proteomics analysis between ND and D pupae was performed 1 and 15 d after injection. A total of 3,255 proteins were identified, of which 190 and 463 were found to be differentially abundant proteins (DAPs) in ND1 vs D1 and ND15 vs D15 comparisons, respectively. The reliability and accuracy of LFQ method was validated by qRT-PCR. Functional analyses of DAPs, including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and protein-protein interaction (PPI) network construction, were conducted. The results revealed that the diapause program of B. minax is closely associated with several physiological activities, such as phosphorylation, chitin biosynthesis, autophagy, signaling pathways, endocytosis, skeletal muscle formation, protein metabolism, and core metabolic pathways of carbohydrate, amino acid, and lipid conversion. The findings of this study provide insights into diapause program of B. minax and lay a basis for further investigation into its underlying molecular mechanisms.


Assuntos
Diapausa de Inseto/fisiologia , Proteínas de Insetos/fisiologia , Mapas de Interação de Proteínas/fisiologia , Tephritidae/crescimento & desenvolvimento , Animais , Citrus/parasitologia , Diapausa de Inseto/efeitos dos fármacos , Ecdisterona/farmacologia , Proteínas de Insetos/análise , Doenças das Plantas/parasitologia , Doenças das Plantas/prevenção & controle , Mapeamento de Interação de Proteínas , Proteômica , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento , Tephritidae/efeitos dos fármacos
16.
Insect Biochem Mol Biol ; 127: 103475, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33059019

RESUMO

MicroRNAs (miRNAs) are endogenous small noncoding RNAs (18-25 nt) that are involved in many physiological processes including development, cancer, immunity, apoptosis and host-microbe interactions through post-transcriptional regulation of gene expression. In this study, we measured the profile of small RNAs over the developmental transitions of the oriental fruit fly Bactrocera dorsalis from egg hatching, molting, and pupation to adult eclosion. We identified 250 miRNAs, including 83 known and 167 novel miRNAs, and 47 isomiRNAs. In addition, we identified the miRNAs differentially expressed over the developmental transitions. Interestingly, the miR-309 cluster, the miR-2 cluster/family and the let-7 cluster were among these differentially expressed miRNAs, suggesting a role in the regulation of egg hatching, molting and pupation/adult eclosion, respectively. Moreover, a detailed analysis of the temporal expression patterns of 14 highly expressed miRNAs in the pupal stage revealed three types of expression profiles. Furthermore, injection of a miR-100 mimic in the 3rd instar larvae resulted in a significant decrease in pupation and adult eclosion rates, whereas injection of a miR-317 antagomir resulted in a significant decrease in the pupation rate and a decrease in the pupation time, indicating that miR-100 and miR-317 are involved in the process of pupation. Finally, injection of a miR-100/miR-285 mimic or antagomir in pupae resulted in a significant decrease in the eclosion rate and a significant increase in the prevalence of a partial eclosion phenotype, implying the involvement of miR-100 and miR-285 in the process of adult eclosion. This study identified critical miRNAs involved in the transitions of this important holometabolic model and pest insect B. dorsalis from egg hatching to adult eclosion, thus providing a useful resource for exploring the regulatory role of miRNAs during insect post-embryonic development.


Assuntos
Regulação da Expressão Gênica , MicroRNAs/genética , Muda/genética , Tephritidae/genética , Animais , Perfilação da Expressão Gênica , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , MicroRNAs/metabolismo , Óvulo/crescimento & desenvolvimento , Óvulo/metabolismo , Pupa/genética , Pupa/crescimento & desenvolvimento , Pupa/metabolismo , Tephritidae/crescimento & desenvolvimento , Tephritidae/metabolismo
17.
Eur J Histochem ; 64(3)2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-33029995

RESUMO

The present study investigated the morphology of fresh and brine-cured table olives (TOs) as well as the changes that occur when drupes are attacked by the fruit fly Bactrocera oleae. Morphological analyses were performed using light microscopy (LM) and environmental scanning electron microscopy coupled with energy dispersive spectroscopy (ESEM-EDS). The LM analysis was carried out with visible light to evaluate sections stained with either PAS or Azan mixtures as well as unstained sections observed at fluorescence microscopy. The results of the analyses showed that: i) Azan and PAS staining played a useful complementary role, increasing the information provided by the histological analysis. Indeed, in both fresh and brine-cured TOs, epidermal layers and mesocarpal cells were clearly revealed, including sclereid cells. The histological analysis allowed also to identifying the presence of secoiridoid-biophenols (seco-BPs) in both cell walls and vacuoles, as well as in the drupe regions that had been attacked by fruit flies, where they were found at higher concentrations; ii) in fresh and brine-cured olives, the excitation at 480 nm revealed the distribution of the fluorophores, among which the seco-BP are enclosed; iii) the ESEM-EDS analysis revealed the natural morphology of fresh olives, including the dimensions of their cell layers and the size and depth of the mechanical barriers of suberized or necrotic cells around the larva holes. In addition, the elemental composition of regions of interest of the drupe was determined in fresh and brine-cured TOs. The results highlighted the effectiveness of combined use of LM and ESEM-EDS in order to obtain a picture, as complete as possible, of the structural morphology of TOs. Such analytical combined approach can be used to support multidisciplinary studies aimed at the selection of new cultivars more resistant to fly attack.


Assuntos
Larva/patogenicidade , Olea/citologia , Olea/parasitologia , Tephritidae/patogenicidade , Animais , Infecções/parasitologia , Infecções/patologia , Iridoides/análise , Microscopia Eletrônica de Varredura , Olea/química , Fenóis/análise , Patologia Vegetal , Sais/química , Espectrometria por Raios X , Tephritidae/crescimento & desenvolvimento
18.
Proc Natl Acad Sci U S A ; 117(38): 23960-23969, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32900926

RESUMO

Many organisms enter a dormant state in their life cycle to deal with predictable changes in environments over the course of a year. The timing of dormancy is therefore a key seasonal adaptation, and it evolves rapidly with changing environments. We tested the hypothesis that differences in the timing of seasonal activity are driven by differences in the rate of development during diapause in Rhagoletis pomonella, a fly specialized to feed on fruits of seasonally limited host plants. Transcriptomes from the central nervous system across a time series during diapause show consistent and progressive changes in transcripts participating in diverse developmental processes, despite a lack of gross morphological change. Moreover, population genomic analyses suggested that many genes of small effect enriched in developmental functional categories underlie variation in dormancy timing and overlap with gene sets associated with development rate in Drosophila melanogaster Our transcriptional data also suggested that a recent evolutionary shift from a seasonally late to a seasonally early host plant drove more rapid development during diapause in the early fly population. Moreover, genetic variants that diverged during the evolutionary shift were also enriched in putative cis regulatory regions of genes differentially expressed during diapause development. Overall, our data suggest polygenic variation in the rate of developmental progression during diapause contributes to the evolution of seasonality in R. pomonella We further discuss patterns that suggest hourglass-like developmental divergence early and late in diapause development and an important role for hub genes in the evolution of transcriptional divergence.


Assuntos
Adaptação Fisiológica/genética , Diapausa/genética , Tephritidae , Transcriptoma/genética , Animais , Drosophila melanogaster/genética , Estudo de Associação Genômica Ampla , Estações do Ano , Tephritidae/genética , Tephritidae/crescimento & desenvolvimento
19.
J Insect Physiol ; 126: 104094, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32783957

RESUMO

Methoprene supplements added to diets of yeast hydrolysate and sugar promote early expression of sexual behaviour and mating in male Queensland fruit fly (Bactrocera tryoni; 'Q-fly') and show promise as a pre-release treatment for sterile insect technique programs. Currently it is not known whether the early mating behaviour of methoprene-treated male Q-flies is only behavioural or is coupled with accelerated development of reproductive organs. Accordingly, the present study investigates whether incorporation of methoprene into diets of yeast hydrolysate and sugar (1:3) or sugar alone, accelerate development of testes, ejaculatory apodeme, and accessory glands in male Q-flies and ovaries in females. All organs increased in size as the flies aged and matured, and development rate of all organs was far greater when the flies were provided yeast hydrolysate in addition to sugar. Incorporation of methoprene into diets containing yeast hydrolysate was found to strongly accelerate development of testes and ejaculatory apodeme, but not accessory glands, in males. In the absence of yeast hydrolysate, methoprene treatment had only a modest effect on male organ development. In contrast to males, development of ovaries in female Q-flies did not respond to dietary methoprene supplements, regardless of whether they were fed yeast hydrolysate and sugar or sugar alone. These findings of diet-dependent effects of methoprene supplements on reproductive organs are a close match to previous studies investigating effects of methoprene supplements on mating behaviour. Overall, methoprene supplements substantially enhance the positive effects of protein rich adult diet on the early expression of sexual behaviour and accelerate development of reproductive organs in male, but not female, Q-flies. Methoprene supplements added to pre-release diets of yeast hydrolysate and sugar show promise as a means of accelerating reproductive development of Q-flies released in sterile insect technique programs, and may also bias operational sex ratio in favour of males.


Assuntos
Genitália/efeitos dos fármacos , Metoprene/farmacologia , Tephritidae/crescimento & desenvolvimento , Animais , Dieta , Suplementos Nutricionais , Feminino , Controle de Insetos/métodos , Masculino , Ovário/efeitos dos fármacos , Controle Biológico de Vetores/métodos , Saccharomyces cerevisiae , Razão de Masculinidade , Testículo/efeitos dos fármacos
20.
J Insect Sci ; 20(4)2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32809019

RESUMO

The melon fly, Zeugodacus cucurbitae (Coquillett), is a serious pest of many fruits and vegetables throughout the world. Here we have developed an easy and quick-to-prepare solid medium with multiple benefits including reductions in post-rearing waste, storage space, and labor for rearing Z. cucurbitae larvae. The development time from egg to pupa was 19.11 d when larvae were reared on the artificial diet, slightly longer than 17.73 d on pumpkin and 17.13 d on cucumber. Zeugodacus cucurbitae achieved higher values of pupal weight, length, and width on the artificial diet than two natural diet controls. The rates of pupation and adult emergence of Z. cucurbitae grown on the solid medium were comparable with those on pumpkin and cucumber. Furthermore, determined by age-specific two-sex life table method, the age-specific survival rate of Z. cucurbitae was higher on the artificial diet than cucumber but lower than pumpkin. The reproductive ability and population dynamics of Z. cucurbitae were not significantly affected on the solid medium compared with those on the two natural diets. The results suggest that our solid artificial diet is excellent for rearing Z. cucurbitae larvae in laboratory and may be used for its mass rearing, therefore facilitating its research and control.


Assuntos
Ração Animal/análise , Entomologia/métodos , Controle de Insetos/métodos , Tábuas de Vida , Tephritidae/crescimento & desenvolvimento , Animais , Dieta , Aptidão Genética , Larva/genética , Larva/crescimento & desenvolvimento , Tephritidae/genética
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