Anastrepha Fraterculus Research Articles

Molecular evolution and genetic diversity of defective chorion 1 in Anastrepha fraterculus and Anastrepha obliqua (Diptera, Tephritidae).

The family Tephritidae comprises numerous fruit fly species, some of which are economically significant, such as several in the genus Anastrepha. Most pest species in this genus belong to the fraterculus group, characterized by closely related species that are difficult to differentiate due to recent divergence and gene flow. Identifying genetic markers for their study is paramount for understanding the group's evolution and eventual phytosanitary control. Because there is variation in eggshell morphology among species in the genus, the study of the rapidly evolving defective chorion 1 (dec-1) gene, which is crucial for chorion formation and reproduction, could provide relevant information for Anastrepha differentiation. We compared transcriptome sequences of dec-1 from two of the most important pest species in the genus, Anastrepha fraterculus and Anastrepha obliqua to dec-1 sequences from Anastrepha ludens, which was used for structure prediction. Furthermore, we amplified a conserved exon across populations of these species. These data revealed three alternative transcripts in A. fraterculus and A. obliqua, consistent with patterns found in other Tephritidae; we obtained orthologous sequences for these other tephritids from NCBI to investigate patterns of selection affecting this gene at different hierarchical levels using different methods. These analyses show a general pattern of purifying selection across the whole gene and throughout its history at different hierarchical levels, from populations to more distantly related species. That notwithstanding, we still found evidence of positive and episodic diversifying selection at different levels. Different parts of the gene have shown distinct evolutionary rates, which were associated with the diverse proproteins produced by posttranslational changes of DEC-1, with proproteins that are incorporated in the chorion earlier in egg formation being in general more conserved than others that are incorporated later. This correlation appears more evident in certain lineages, including the branch that separates Anastrepha, as well as other internal branches that differentiate species within the genus. Our data showed that this gene shows remarkable variation across its different exons, which has proven to be informative at different evolutionary levels. These changes hold promise not only for studying differentiation in Anastrepha but also for the eventual management of selected pest species.

Demographic parameters of Pachycrepoideus vindemiae (Hymenoptera: Pteromalidae) reared on Drosophila suzukii (Diptera: Drosophilidae), Ceratitis capitata (Diptera: Tephritidae), and Anastrepha fraterculus (Diptera: Tephritidae) puparia.

Pachycrepoideus vindemiae (Rondani) is a solitary generalist pupal ectoparasitoid that parasitizes dipterans of various families and genera. This study aimed to evaluate Anastrepha fraterculus (Wiedemann), Ceratitis capitata (Wiedemann), and Drosophila suzukii (Matsumura) to determine the best host for the development and mass production of parasitoid P. vindemiae in the laboratory. The experiments were performed in air-conditioned rooms at a temperature of 25 ± 2 °C, relative humidity of 70% ± 10%, and photophase of 12h. Moreover, 24-h-old pupae of A. fraterculus, C. capitata, and D. suzukii were provided daily to 25 pairs of the parasitoid. The following parameters were determined: percentage of parasitism, percentage of emergence, hind tibia size, sex ratio, and longevity. A fertility life table was established using biological data. Notably, P. vindemiae parasitized the pupae of all 3 hosts but did not affect the sex ratio of the offspring. Parental parasitoids from the pupae of A. fraterculus and C. capitata lived longer than those from the pupae of D. suzukii. However, for all other parameters, parasitoids from D. suzukii showed better performance than those from other hosts, with shorter intervals between generations (T) and a higher net reproduction rate (Ro), intrinsic rate of increase (rm), and finite rate of increase (λ).

Molecular Markers for Analyses of Genetic Diversity within the Anastrepha fraterculus Complex with Emphasis on Argentine Populations.

The South American fruit fly Anastrepha fraterculus (Wiedmann) has a vast range extending from northern Mexico, through Central America, to South America where it is an extremely polyphagous pest of wild and cultivated fruits. It is a complex of cryptic species currently composed of eight recognised morphotypes: "Mexican", "Venezuelan", "Andean", "Peruvian", "Ecuadorian", and the three Brazilian morphotypes "Brazilian-1", "Brazilian-2", and "Brazilian-3". Molecular markers that can identify the member species of the complex are crucial for the implementation of effective pest control measures, such as the sterile insect technique. The object of this study was to evaluate the use of the internal transcribed spacer 2 (ITS2) sequence for discriminating several members of the A. fraterculus cryptic species complex (Mexican, Peruvian, and Brazilian-1) and a related species, Anastrepha schultzi Blanchard. The analysis highlighted significant genetic differentiation between the evaluated morphotypes, allowed their discrimination within the A. fraterculus cryptic species complex, and provided new insights into their genetic relationships. The ITS2 marker provides a basis for the development of taxonomic keys for the discrimination of the cryptic taxa within the A. fraterculus cryptic species complex. ITS2 also represents an important marker for the poorly studied species A. schultzi.

Efficiency of handmade attractants in fruit fly control

Fruit flies (Diptera: Tephritidae) are considered the main pests of fruit crops worldwide, and using traps and attractants are useful tools for their effective monitoring and control. The study's main objective was to evaluate the capacity to capture fruit flies with non-commercially produced attractants and use the Lin and Binns method to evaluate their performance. Five food attractants were evaluated to capture the genera Anastrepha and Ceratitis. The study was carried out in five municipalities of Táchira State, Venezuela, during two semesters, using a completely randomized design with four replications. The experimental unit was represented by a JD EuGo 97 trap, baited with 300 mL of the respective attractant solution. The attractants did not perform equally in all environments, while no variation was observed in the level of trap capture between the two semesters studied. Anastrepha fraterculus was the only species collected at all altitudinal levels, suggesting an adequate capacity to adapt to different environments. The commercial product PedGo plus was the most effective attractant for fly trapping, and it may be an appropriate alternative for use by fruit growers in the control of this pest. Although it was the most efficient attractant in most of the environments studied, molasses + urea proved to be an alternative to replace PedGo plus and Nulure.

Different Protein Sources of Larval Diet on the Rearing of Anastrepha fraterculus (Diptera: Tephritidae): Biological and Nutritional Analyses.

Anastrepha fraterculus (Diptera: Tephritidae) is considered an important pest in Neotropical countries. The laboratory rearing of this species should reproduce conditions in nature; thus, special attention is required to the nutritional quality of diets for larval development. Protein components (wheat germ) are costly and account for most production costs in lab insect rearing. In this sense, this work aimed to identify ingredients to replace wheat germ, without compromising diet quality for the lab rearing of A. fraterculus. We tested diets composed of whole rice flour, corn flour, and a mixture of whole wheat flour + soybean flour as substitutes for wheat germ as well as a raw wheat germ diet, considered the control. The protein sources used in the larval diet influenced the biological performance of both the larval and adult stages of A. fraterculus during six generations. The diet containing corn flour and wheat germ showed similar results in the different developmental parameters. The diet with rice flour also provided adequate biological development for A. fraterculus throughout its life cycle and was nutritionally similar to the control. As it is local product, rice flour can replace wheat germ (costly imported product) in artificial diets for A. fraterculus, reducing production costs by roughly 30% without compromising the biological and nutritional parameters of the insects. Faced with this, the rice flour can be considered suitable for the mass rearing of A. fraterculus in the laboratory.

Species Diversity of Anastrepha Fruit Flies (Diptera: Tephritidae) in Environments with Different Levels of Anthropogenic Changes.

Studies on the diversity of Anastrepha species have been conducted mainly in agricultural orchards due to the economic importance of this insect group, consequently, research on fruit flies in undisturbed environments is scarce. Moreover, very few studies have investigated the diversity of fruit flies in urban areas, where fruit flies survive under native or exotic hosts. Thus, to understand the diversity of Anastrepha species in an environment with different anthropization degrees, surveys were carried out in four areas of the "Luiz de Queiroz" campus, in Piracicaba, São Paulo State (Brazil), using Multilure traps with putrescine and ammonium acetate for 12 months. The software R 3.6.3 was used to characterize the fruit fly community and the faunistic analysis was carried out using the ANAFAU program. The analysis of species richness and total abundance of fruit flies among the sites was carried out using the rarefaction method and adjustment to the generalized linear model (GLM) using the Poisson distribution, respectively. We collected 1,080 females and 14 species of Anastrepha in the four sampled sites. Anastrepha fraterculus and A. obliqua were the predominant species (behavioral patterns). Similar to agricultural sites, A. fraterculus and A. obliqua also show a predominant occurrence in urban environments.

Life history and overwintering in multi‐ and univoltine species of family Tephritidae in a subtropical region of northwestern Argentina

AbstractAmong phytophagous insects, life history often evolves as a strategy to cope with seasonality in host plant availability. Whereas specialization often leads to dormancy, aestivation, or longevity, polyphagous species bridge between periods of host availability by exploiting alternative host plants. The aim of the present work was to characterize the life histories of four species of specialist and generalist uni‐ and multivoltine frugivorous fruit flies – Ceratitis capitata Wiedemann, Anastrepha fraterculus Wiedemann, Rhagoletis blanchardi Aczel, and Rhagoletotrypeta pastranai Aczel (all Diptera: Tephritidae) – inhabiting in sympatry in Las Yungas phytogeographical province in Tucumán (northwestern Argentina). For this purpose, infested host plant fruits were sequentially collected during two consecutive years, and flies recovered from these fruits were subjected to demographic experiments to establish longevity and overwintering mechanisms. The results indicated that life cycles were tightly related to host fruit availability, where multivoltine species sequentially exploit different host plants over the year, whereas univoltine species must undergo pupal dormancy to reach the next host fructification period and may extend the duration of dormancy when climatic conditions are acyclic and unpredictable. The present study may broaden knowledge about diapausing Tephritidae in subtropical regions and may contribute to an increased conceptual basis for the improvement of pest control strategies, such as the sterile insect technique (SIT).

Volatiles of essential oils and yeast derivatives influence mating behaviour of Anastrepha fraterculus males under field cage conditions

AbstractThe sterile insect technique (SIT) is used for the management of tephritid fruit fly pests. The South American fruit fly, Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae), is one potential pest to be targeted by means of SIT. The success of SIT depends, to a large extent, on the sexual performance of sterile males. Various approaches have been evaluated with the aim of improving their sexual performance. These include the exposure to plant‐derived compounds and/or the provision of protein sources in the adults' diet capable of stimulating male mating success. The present study aimed to determine whether exposure to volatiles of Citrus limon (L.) Burm. F. (Rutaceae) essential oil and limonene confers a mating advantage to A. fraterculus laboratory males fed two distinct dietary regimes when competing with wild males for wild females under field cage conditions. Dietary regimes were, one, with non‐hydrolysed brewer's yeast and sugar (1:3 ratio), and the other with brewer's yeast hydrolysate enzymatic and sugar (1:12 ratio). The effect was evaluated in four variables associated with mating success: number of copulas obtained, latency to mate, copula duration, and copula location. Exposure to volatiles did not affect the number of matings achieved, irrespective of the diet given to the males. When laboratory males were fed with brewer's yeast hydrolysate, the effect of volatile exposure was shown in latency to mate, copula duration, and copula location. When the laboratory males were fed with non‐hydrolysed brewer's yeast, the effect of volatile exposure was shown only in copula duration. Laboratory males fed brewer's yeast hydrolysate achieved the same number of matings as wild males, whereas laboratory males fed non‐hydrolysed brewer's yeast had lower performance.

Does the Neotropical‐native parasitoid Ganaspis pelleranoi successfully attack the worldwide invasive pest Drosophila suzukii?

AbstractThe Asian Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is a harmful invasive pest widespread throughout Argentinian fruit‐producing regions. It coexists with both pests, the sub‐Saharan African Ceratitis capitata (Wiedemann) and the Neotropical‐native Anastrepha fraterculus (Wiedemann) (both Diptera: Tephritidae), in northwestern Argentina. The Neotropical‐native parasitoid Ganaspis pelleranoi (Brèthes) (Hymenoptera: Figitidae) is frequently found in non‐crop fruit infested by those frugivorous dipterans. The northwestern Argentinian region is known for producing and exporting berries and citrus, which are affected by those pests. Thus, eco‐friendly control strategies are under assessment. This study mainly assessed the potential of the G. pelleranoi population lineage from Tucumán (GpTuc) as a D. suzukii biocontrol agent. First, both the host‐killing effectiveness and the reproductive success of GpTuc on larvae of D. suzukii, C. capitata, A. fraterculus, and Drosophila melanogaster Meigen were compared in no‐choice tests under laboratory conditions. Then, the GpTuc host preference was evaluated in dual‐choice tests (D. suzukii vs. C. capitata or A. fraterculus) under laboratory and field conditions. Naive parasitoid females were allowed to forage for 8 h on screen‐covered Petri dishes filled with host larvae under laboratory conditions and for 48 h on peaches inoculated with host larvae under field conditions. Host puparia dissections were performed to determine the number and condition of parasitoid eggs, first and second instars, such as alive/dead, without/with melanization process, and proportions of parasitized, superparasitized, and dead puparia. Drosophila suzukii was not a suitable host for the successful development of GpTuc immature stages as they did not overcome the host's immune system. However, GpTuc performed efficiently regarding D. suzukii mortality, but parasitoid specificity was restricted to both tephritid species as only thriving offspring were achieved from them. Interestingly, the effectiveness of GpTuc on D. suzukii increased when it co‐occurred with C. capitata instead of A. fraterculus, the preferred host.

Genome report: chromosome-scale genome assembly of the West Indian fruit fly Anastrepha obliqua (Diptera: Tephritidae).

The West Indian fruit fly, Anastrepha obliqua, is a major pest of mango in Central and South America and attacks more than 60 species of host fruits. To support current genetic and genomic research on A. obliqua, we sequenced the genome using high-fidelity long-read sequencing. This resulted in a highly contiguous contig assembly with 90% of the genome in 10 contigs. The contig assembly was placed in a chromosomal context using synteny with a closely related species, Anastrepha ludens, as both are members of the Anastrepha fraterculus group. The resulting assembly represents the five autosomes and the X chromosome which represents 95.9% of the genome, and 199 unplaced contigs representing the remaining 4.1%. Orthology analysis across the structural annotation sets of high quality tephritid genomes demonstrates the gene annotations are robust, and identified genes unique to Anastrepha species that may help define their pestiferous nature that can be used as a starting point for comparative genomics. This genome assembly represents the first of this species and will serve as a foundation for future genetic and genomic research in support of its management as an agricultural pest.

The Population Dynamics and Parasitism Rates of Ceratitis capitata, Anastrepha fraterculus, and Drosophila suzukii in Non-Crop Hosts: Implications for the Management of Pest Fruit Flies.

Understanding the seasonal dynamics inherent to non-crop host-fruit fly-parasitoid interactions is vitally important for implementing eco-friendly pest control strategies. This study assessed the abundance and seasonal infestation levels of three pest fly species, Ceratitis capitata (Wiedemann), Anastrepha fraterculus (Wiedemann), Drosophila suzukii (Matsumura), as well as the related saprophytic drosophilids, and their natural parasitism in a disturbed wild habitat characterized by non-crop hosts in northwestern Argentina over 40 months. Juglans australis Griseb (walnut), Citrus aurantium L. (sour orange), Eriobotrya japonica (Thunb.) Lindley (loquat), Prunus persica (L.) Batsch (peach), and Psydium guajava L. (guava) were sampled throughout their fruiting seasons. Fruits were collected from both the tree canopies and the ground. The most abundant puparia was A. fraterculus, followed by C. capitata and D. suzukii. Drosophila species from the D. melanogaster group were highly abundant only in fallen fruits. Spatiotemporal overlaps of different host fruit availability provided suitable sources for pest proliferation throughout the year. The populations of both invasive pests peaked from December to January, and were related to the highest ripe peach availability, whereas the A. fraterculus population peaked from February to April, overlapping with the guava fruiting period. The three pest fly species were parasitized mainly by three generalist resident parasitoids, which are potential biocontrol agents to use within an integrated pest management approach.

Efficacy of alkaline hydrolyzed torula yeast for monitoring Anastrepha spp.

AbstractAnastrepha fruit flies (Diptera: Tephritidae) are important pests of several crops in the Americas. Alkaline hydrolysis of proteins represents a potential source of novel attractants. Previous studies revealed a higher response by Anastrepha obliqua (Macquart) to alkaline hydrolyzed torula yeast compared with other attractants. Under field conditions, captures of Anastrepha fraterculus (Wiedemann), Anastrepha ludens (Loew), and Anastrepha serpentina (Wiedemann) were significantly higher in traps baited with alkaline hydrolyzed torula yeast than in traps baited with acid hydrolyzed protein (Captor) + borax. Fly attraction to alkaline hydrolyzed torula yeast varied with species but was higher in the 1st week and decreased after 2 or 3 weeks of use in the field. The release of ammonia gas from alkaline hydrolyzed torula yeast and CeraTrap was reduced after 3 weeks, but CeraTrap remained effective in the capture of flies whereas alkaline hydrolyzed torula yeast did not. No improvement in fly captures was observed for aged alkaline hydrolyzed torula yeast when 1% ammonium acetate was added to traps. The addition of propylene glycol or benzalkonium chloride did not improve trap captures over time. Although CeraTrap has advantages in attractiveness and durability, the attraction, simplicity, and low cost make alkaline hydrolyzed torula yeast a promising attractant when compared with the standard Captor + borax in short‐term monitoring programs targeted at Anastrepha pests.

Responses of two Anastrepha species' immature stages infesting preferential hosts to different temperature exposures.

Anastrepha fraterculus (Wiedemann) and A. obliqua (Macquart) are important pests of fruit crops. In Brazil, these species cause damage to fruit growing in the South (annual average temperature of 20.9°C) and Northeast (average yearly temperature of 24°C). We evaluated the effect of temperature on the viability and development time of A. fraterculus and A. obliqua immature stages in their respective preferred hosts, guava (Psidium guajava L., Myrtaceae) and mango (Mangifera indica L., Anacardiaceae). The duration of egg and pupal stages, egg to pre-pupa, and viability of egg and pupal stages under different temperatures (15, 20, 25, 30, and 35°C) were assessed. For both species, development time decreased with increasing temperature. Viability in the evaluated stages was only observed between 15 and 30°C. However, the species responded differently to the exposure temperatures (15 and 30°C), especially in the pupal stage and from egg to pre-pupa. Anastrepha fraterculus showed a lower tolerance to high temperatures, especially in the pupal stage and from egg to pre-pupa, which may explain its lower importance and economic impact in warmer Brazilian regions. Anastrepha obliqua had a lower tolerance at 15°C, indicating greater adequacy for temperatures above 20°C, characteristic of Northeast Brazil, suggesting the capacity to spread to cooler areas with rising temperatures.

Moscas frugívoras (Diptera: Tephritidae; Lonchaeidae) associadas a goiabeira: diversidade de espécies, parasitoides e flutuação populacional no Espírito Santo, Brasil

ABSTRACT The commercial cultivation of guava tree (Psidium guajava L.) occurs in all Brazilian regions, where fruit flies cause direct losses to production and affect fresh fruit exports due to quarantine restrictions. This study aimed to determine the incidence, diversity and population fluctuations of frugivorous fly species that infest guava trees, as well as to survey their associated parasitoids, in the Espírito santo state, Brazil. Fruits and flies captured in traps were sampled in three guava-producing regions. Anastrepha fraterculus (Wied.) was the main species associated with guava trees, particularly in the coastal region. Anastrepha chiclayae was recorded for the first time associated with guava trees in Brazil. Medfly was not considered an important species. Neosilba zadolicha was the most common Lonchaeidae species collected, but with low importance. Higher populations of frugivorous flies were found in hot and humid areas. Two population peaks of A. fraterculus were observed during October (spring) and from March to April (summer-autumn). Tephritid flies occurred in all surveyed regions, with higher infestations in the coastal area, followed by the northern and mountain regions, respectively. Doryctobracon areolatus and Aganaspis pelleranoi were the most common species of parasitoids; however, the natural biological control of frugivorous flies in guava trees was very low and had little impact on fruit fly populations.

Diversity of Anastrepha spp. (Diptera: Tephritidae) in the Chaco Biome.

Species of the genus Anastrepha cause injuries to several fruits and vegetables in the Nearctic and Neotropical regions. Among these species, many are present in Brazil. In this study, we surveyed the existing Anastrepha species in the Brazilian Chaco Biome. We evaluated possible influences of climate and vegetation on the occurrence of Anastrepha spp. For this, we used traps and hydrolyzed protein as bait. Collections were carried out in three distinct floristic compositions in the Chaco biome, from permanently dry areas to flooded sites. We identified Anastrepha fraterculus (Wiedemann, 1830), A. sororcula Zucchi 1979, A. undosa Stone 1942, and A. daciformis Bezzi 1909. The dry and flooded environment did not influence the occurrence of Anastrepha species. The presence of multiple hosts increases the number of species. The richness and abundance of Anastrepha species are lower in the Brazilian Chaco than in other native environments.

New native host plant records for frugivorous flies (Diptera: Tephritidae, Lonchaeidae) in Northeastern Brazil

The fruit flies Anastrepha fraterculus (Wiedemann, 1830), Anastrepha sororcula Zucchi, 1979, Ceratitis capitata (Wiedemann, 1824) (Diptera: Tephritidae) and Neosilba pendula (Bezzi, 1989) (Diptera: Lonchaeidae) are recorded for the first time emerging from Campomanesia dichotoma (O.Berg) Mattos and Campomanesia ilhoensis Mattos (Myrtaceae), two native species occurring in fragments of Atlantic Forest over dunes, in the northernmost limit of this biome in the state of Rio Grande do Norte, Brazil. The flies emerged from fruit samples obtained at the conservation area at Parque Estadual Dunas do Natal. The parasitoids that emerged from the puparia were also recorded, with Aganaspis pelleranoi (Brèthes) being recorded for the first time for the state. These records are of importance for monitoring and further understanding of the cycles on alternative hosts especially where these species are considered agricultural pests.

Toxicity and residual effects of spinetoram on adults and larvae of Anastrepha fraterculus and Ceratitis capitata (Diptera: Tephritidae)

The use of organophosphate insecticides is one of the main strategies for the chemical control of Anastrepha fraterculus and Ceratitis capitata (Diptera: Tephritidae) in Brazil. Although organophosphate insecticides are effective in population suppression, their constant use (up to 5 applications/harvest) may favor pest resistance. Nevertheless, some organophosphate insecticides are highly toxic to natural enemies and thus their use has been banned. In this study, we investigated acute and residual toxicity of different doses of insecticide spinetoram for the control of larvae and adults of A. fraterculus and C. capitata under laboratory and field conditions. Spinetoram (Delegate 250WG™) showed high toxicity to adults and larvae of A. fraterculus and C. capitata (mortality>80%), based on topical application and ingestion bioassays. At the highest dose evaluated, 5.0 g a.i. (active ingredient) per 100 L of water, spinetoram was statistically similar to organophosphate (Lorbans 480BR™), but superior to neonicotinoid (Eleitto™), standard products for fruit fly control in Brazil. In addition, at doses 3.75 and 5 g a.i.100 L-1, spinetoram showed significant toxicity (mortality>70%) via tarsal contact for both species. Furthermore, toxic effects at depth were observed on larvae of 1st, 2nd, and 3rd instars of fly species in apple and peach fruits, reducing adult emergence by up to 90%. In the field, the highest dose evaluated (spinetoram 5 g a.i.100 L-1) reduced infestation of A. fraterculus by 90%. The results show that spinetoram could be used in the management of A. fraterculus and C. capitata, also as an alternative control for insect resistance management programs.

Rapid cryptic divergence of the Anastrepha fraterculus complex in the Late Pleistocene: a phylogeographical–ecological approach

Abstract The Anastrepha fraterculus complex (AF complex) is a complex of fruit fly species consisting of eight morphotypes distributed across the Americas. In this study, landscape genetics, phylogeographical inferences and coalescence simulations were used to unveil the evolutionary history of the AF complex. Nuclear ribosomal ITS1 sequences from 331 samples distributed in 10 American countries throughout 32 ecoregions and seven biomes were analysed. Results showed high levels of diversity, intraspecific divergence and structuring associated with the different morphotypes of the complex. The analysis of gene flow and genetic diversity showed a clear geographical and environmental pattern. The morphotype–environment association suggested that the cryptic divergence process has involved local adaptation as a mechanism to withstand harsh, novel or variable conditions. The analysis showed a rapid divergence between morphotypes. Haplotypes have been diverging for ~27 000 years before the present, probably enhanced by environmental changes during the Last Glacial Maximum. Diversity estimators and neutrality tests revealed that populations have been experiencing a recent linear growth, starting in the Early Holocene (~11 500 years before the present). The Bayesian phylogeographical and ecological clustering approach detected five spatially separated and ecologically differentiated clusters. Additionally, equatorial Amazonia was indicated to be the most probable ancestral centre of origin for the AF complex.

Development of a Hydrothermal Treatment to Control Fruit Flies (Diptera: Tephritidae) and Maintain the Quality of ‘Fuyu’ Persimmons

Because of fruit fly incidence, importing countries impose phytosanitary barriers to prevent the entry and spread of infested fruits. When fruits are not grown in fruit fly-free areas, some countries require quarantine treatments for fruit disinfestation before or during shipping. The objective of this study was to evaluate the use of a hydrothermal treatment as a quarantine treatment for ‘Fuyu’ persimmons infested with two fruit fly species to maintain fruit quality. Hot water treatment (HWT) was applied to eggs and third-instar larvae of Ceratitis capitata and Anastrepha fraterculus in vitro at 42º, 44º, 46º, 48º, and 50 ºC for 20, 30, 40, 50, 60, and 90 min. Persimmon fruit infested by C. capitata and A. fraterculus eggs and third-instar larvae were subjected to 44 ºC for 60 and 90 min, 46 °C for 20 and 30 min; and 48 °C for 20 min. Untreated infested fruits were used to estimate the rate of fruit fly infestation. Pulp firmness, skin and pulp colors, titratable acidity, pH, and total soluble solids were measured to evaluate the effect of HWT on fruit quality. The increase in temperature and immersion time decreased the pupation and emergence of adults of C. capitata and A. fraterculus in vitro. C. capitata eggs treated in vitro at temperatures ≥ 46 ºC for 30 min did not produce pupae. A. fraterculus eggs treated in vitro at 46 ºC for 20 min exhibited no larval hatching. No pupae were obtained from third-instar larvae of both fruit fly species treated at 44 ºC for 60 min. Infested ‘Fuyu’ persimmons treated at 44 ºC for 90 min did not exhibit the emergence of adults of C. capitata or A. fraterculus. Except for pH, in general, ‘Fuyu’ persimmons subjected to HWT demonstrated no alterations of skin or pulp texture, skin coloration, titratable total acidity, or total soluble solids. The results suggest that HWT is a potential quarantine treatment for the export of ‘Fuyu’ persimmons.

Phylogenomic analysis provides diagnostic tools for the identification of Anastrepha fraterculus (Diptera: Tephritidae) species complex.

Insect pests cause tremendous impact to agriculture worldwide. Species identification is crucial for implementing appropriate measures of pest control but can be challenging in closely related species. True fruit flies of the genus Anastrepha Schiner (Diptera: Tephritidae) include some of the most serious agricultural pests in the Americas, with the Anastrepha fraterculus (Wiedemann) complex being one of the most important due to its extreme polyphagy and wide distribution across most of the New World tropics and subtropics. The eight morphotypes described for this complex as well as other closely related species are classified in the fraterculus species group, whose evolutionary relationships are unresolved due to incomplete lineage sorting and introgression. We performed multifaceted phylogenomic approaches using thousands of genes to unravel the evolutionary relationships within the A. fraterculus complex to provide a baseline for molecular diagnosis of these pests. We used a methodology that accommodates variable sources of data (transcriptome, genome, and whole-genome shotgun sequencing) and developed a tool to align and filter orthologs, generating reliable datasets for phylogenetic studies. We inferred 3031 gene trees that displayed high levels of discordance. Nevertheless, the topologies of the inferred coalescent species trees were consistent across methods and datasets, except for one lineage in the A. fraterculus complex. Furthermore, network analysis indicated introgression across lineages in the fraterculus group. We present a robust phylogeny of the group that provides insights into the intricate patterns of evolution of the A. fraterculus complex supporting the hypothesis that this complex is an assemblage of closely related cryptic lineages that have evolved under interspecific gene flow. Despite this complex evolutionary scenario, our subsampling analysis revealed that a set of as few as 80 loci has a similar phylogenetic resolution as the genome-scale dataset, offering a foundation to develop more efficient diagnostic tools in this species group.