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Background: The Tephritidae family, commonly referred to as true fruit flies, comprises of a substantial group within order Diptera. Numerous species within this family are major agricultural pests, with a tendency to infest a wide array of fruits and vegetables in tropical and sub- tropical regions, leading to considerable damage and consequent reductions in the market value of the crops. Methods and results: The current study was aimed to propose a promising solution to the menace posed by fruit flies by offering rapid, accurate and reliable species identification by using character-based DNA barcode methodology. The Tephritid specimens were collected from Cucurbitaceous plants of southern parts of West Bengal, India, and a total of eight species from Tephritidae family were obtained belonging to three genera, namely Bactrocera (Macquart, 1835), Dacus (Fabricius, 1805) and Zeugodacus (Hendel, 1927). Their morphological features were meticulously studied based on available literature, along with genetic analysis based on mitochondrial COI and ND1 gene sequences. A total of 30 uniquely variable sites at nucleotide position 42,48,51,60,66,72, 105,111,144,198,207,243, 273,297,307,318,345,357, 375,378,381,387,399,400, 402,436,444,450,453 and 460 in COI gene were discerned among Tephritid species in the present study. Conclusions: The character-based DNA barcode holds the potential to differentiate closely related species of fruit flies and morphologically look-a-like ones. The novel method will be very significant in terms of rapid, precise and reliable species identification and might be extremely essential for early detection during pest outbreaks by facilitating timely intervention strategies to mitigate crop damage. [ABSTRACT FROM AUTHOR]

Simple Summary: The Mediterranean fruit fly (medfly) is an extremely polyphagous pest, capable of infesting over 300 host plants, making it one of the most significant threats to fruit production globally. The aim of this study was to investigate how developmental temperature and host fruit type affect adult longevity and fecundity in medflies from six geographically distinct populations across Southern to Central Europe. The findings highlight the influence of environmental factors, such as temperature and host fruit, on the life history traits of Ceratitis capitata and underscore the species' ability to adapt to different environments. This work offers important insights into how such adaptations contribute to the spread of this pest species and informs potential strategies for its management, especially in light of ongoing climate change. Temperature and host fruit availability are key factors influencing the life history traits of the Mediterranean fruit fly (medfly) (Ceratitis capitata). This study examines how developmental temperature and host fruit type affect adult longevity and fecundity in medflies from six populations spanning Southern to Central Europe. Larvae were reared on apples and bitter oranges at three constant temperatures (15, 20, and 25 °C), with pupae maintained under the same thermal conditions until adult emergence. Adults were then kept at 25 °C, with longevity and fecundity recorded daily. The results showed that higher developmental temperatures increased adult lifespan across all populations, regardless of host fruit. Similarly, fecundity rates in ovipositing females were higher at higher temperatures. Reproductive periods (pre-oviposition, oviposition, and post-oviposition) varied among populations, indicating population-specific responses. These findings underscore how temperature and host fruit availability shape medfly invasion dynamics, highlighting the species' biological plasticity and adaptation to different environments. This research provides valuable insights for pest management, particularly in the context of climate change, offering strategies to mitigate the spread of medflies into new regions. [ABSTRACT FROM AUTHOR]

The sterile insect technique (SIT) is an environmentally friendly and species-specific method widely used to control agriculturally important fruit flies (Diptera: Tephritide). Previous studies have focused on the effects of releasing a higher proportion of sterile males relative to fertile males on Bactrocera dorsalis populations. In this study, we focused on the impact of releasing a small percentage of sterile males relative to fertile males on B. dorsalis populations. The results showed that when the ratio of wild to sterile males was 1:3, the number of eggs produced within 12 days (5166 eggs) and hatching rate (66%) were significantly lower than those of the control group (6680 eggs and 85%). When the males were released at a ratio of 1:3 for the second time, the hatching and pre-adult survival rates of B. dorsalis progeny were 43% and 37%, respectively. There were also significant decreases in R0, r, λ, and T compared with the control, and after 90 days the population size predicted using the TIMING-MSChart program was reduced by 63%. Overall, these findings indicate that the release of sterile males as a small proportion relative to fertile males resulted in the collapse of the B. dorsalis population. This study establishes a scientific foundation for the release of sterile males in the field and the environmentally friendly prevention and control of B. dorsalis infestations. [ABSTRACT FROM AUTHOR]

BACKGROUND: Many studies have demonstrated that tephritid fruit fly larvae are highly susceptible to entomopathogenic nematodes (EPNs) and may become infected as they enter the soil to pupate. However, the susceptibility of adult tephritids and their suitability as EPN targets have been less studied. We performed laboratory assays with 12 Australian EPN strains of Heterorhabditis bacteriophora, Heterorhabditis indica and Heterorhabditis zealandica in adults of the Queensland fruit fly, Bactrocera tryoni. Infective juveniles were delivered in a yeast hydrolysate solution that is attractive to flies. We also measured the flight ability of adults up to 3 days after treatment. RESULT: Flies that consumed the EPN‐yeast preparation experienced 72.8–84% mortality. Between 33.5% and 46.2% of EPN‐treated adults were still able to fly before death following treatment, mostly within the first day, thereby contributing to EPN dispersal. Another 31.9–39.9% of EPN‐treated flies that were unable to fly died as a result of EPN treatment. Overall, >65% of flies that died following EPN treatment had visible signs of infection and EPN reproduction. CONCLUSION: Our study is foundational to the development of attract‐and‐kill and autodissemination approaches involving EPNs in fruit fly control. Furthermore, H. indica and H. zealandica strains showed the highest potential as biocontrol agents against adult flies. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The evolution of phytophagous insects has resulted in the development of feeding specializations that are unique to this group. The majority of current research on insect palatability has concentrated on aspects of ecology and biology, with relatively little attention paid to the role of insect gut symbiotic bacteria. Symbiont bacteria have a close relationship with their insect hosts and perform a range of functions. This research aimed to investigate the relationship between insect host plant range and gut symbiotic bacteria. A synthesis of the extant literature on the intestinal commensal bacteria of monophagous, oligophagous, and polyphagous tephritids revealed no evidence of a positive correlation between the plant host range and the diversity of larval intestinal microbial species. The gut symbionts of same species were observed to exhibit discrepancies between different literature sources, which were attributed to variations in multiple environmental factors. However, following beta diversity analysis, monophagy demonstrated the lowest level of variation in intestinal commensal bacteria, while polyphagous tephritids exhibited the greatest variation in intestinal commensal bacteria community variation. In light of these findings, this study proposes the hypothesis that exclusive or closely related plant hosts provide monophagy and oligophagy with a stable core colony over long evolutionary periods. The core flora is closely associated with host adaptations in monophagous and oligophagous tephritids, including nutritional and detoxification functions. This is in contrast to polyphagy, whose dominant colony varies in different environments. Our hypothesis requires further refinement of the data on the gut commensal bacteria of monophagy and oligophagy as the number of species and samples is currently limited. [ABSTRACT FROM AUTHOR]

The olive fruit fly Bactrocera oleae (Diptera: Tephritidae) is a main pest of olives, we monitored its dynamics and reproduction from October 2021 to January 2024 using four sampling techniques and control strategies, to prevent economic losses and preserve the olive crop in Biskra region. Mass trapping was the most effective in reducing adult olive fly populations. Pheromone traps, yellow sticky traps, and ammonia phosphate traps were less effective. We recommend the application of integrated management strategies to achieve the best results in controlling olive fruit fly dynamics. [ABSTRACT FROM AUTHOR]

In order to study the biodiversity of fruit flies (Diptera, Tephritidae) in two pomegranate agroecosystems in M'sila (North East of Algeria) and to monitor the dynamics of their populations, we used two types of trapping between October 2017 and November 2018. The first type is based on McPhail traps baited with the pheromone trimedlure and is exclusively intended for the study of the dynamics of the populations of the ceratitis. The second is mass trapping based on a network of olipe traps baited with diammonium phosphate, intended to study both the biodiversity of other fruit flies captured by this trap and their population dynamics. The inventory of Tephritidae revealed the presence of six species namely: Acanthiophilus helianthi (Rossi, 1794), Bactrocera oleae (Rossi, 1790), Ceratitis capitata (Wiedemann, 1824), Dacus frontalis (Becker, 1922), Tephritis nigricauda (Loew, 1856) and Tephritis praecox (Loew, 184 4). We note the rediscovery of D. frontalis 22 years after its first report. Two species of Tephritidae marked their dominance in the traps of the massive trapping network, namely: T. praecox and B. oleae. The use of the density of flies per trap and per day was assessed by calculating the FTD: number of flies per trap per day which constitutes a tool for indicating the level of the population and its monitoring, for phytosanitary alerts related to fruit flies. The FTD values of the fruit fly attracted by the McPhail trap according to the field trips were between 0.1190 at the end of June and 10.7083 (peak) at the beginning of October for the Boukhmissa orchard and between 0.0159 at the end of June and 3.1429 (peak) at the end of October for the Ouled Addi orchard. [ABSTRACT FROM AUTHOR]

Trapping is the cornerstone of the Medfly control strategy, both to monitor population level and as a control method, i.e. mass trapping. This tactic, which is an essential component of IPM against Medfly in Tunisia as in other countries, relies on powerful food-baits that target females. However, these lures are expensive and imported, making the low-income countries dependant to foreign suppliers. Moreover, bait costs is a constraint to scaling-up IPM, particularly for for small-scale farmers. This study presents an attempt to valorize brewer's yeast from a Tunisian brewery, in order to make low cost food-baits for Medfly. Brewer's yeast was processed with papain (0.4 and 0.8%) and ammonium acetate (AA) (1%) into five formulations. The physicochemical composition of the initial product and the baits obtained was determined. A field trial was then carried out to compare the brewer's yeast baits with Biolure®, a standard food-attractant for Medfly. Baits were assessed according three parameters: total Medfly captures, % of Medfly females and selectivity to non-target arthropods (NTA). The best formulations were those with papain and AA that were comparable to Biolure® for Medflies captured; for their selectivity towards NTA, further improvements are needed. The results obtained are encouraging, and research should be continued to improve the quality of brewer's yeast based-attractants, then to assess their performance in reducing Medfly damage when used in mass trapping. Such an initiative, can pave the way for the valorization of brewer's waste, in locally manufactured food-lures for Medfly, thus enhancing the adoption of IPM. [ABSTRACT FROM AUTHOR]

Simple Summary: In this article, we have reviewed and analysed all the available information, including in historical records, on the phenology and infestation rate of fruits by the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann 1824; Diptera, Tephritidae), in the Balkan Peninsula, to illustrate and understand the path of invasion and spread dynamics in the northern Mediterranean region and Central Europe. After the medfly was first discovered in an area of the Aegean Sea in 1915, the pest was then detected in the Peloponnese in the early 1930s, along the entire Adriatic coast in the 1950s, and has been found in the Black Sea area since 2005. Since 2000, a significant increase in the frequency of detections has been recorded in the interior of the Balkan Peninsula, including occasional outbreaks in areas with unfavourable climatic conditions for overwintering, which seems to reduce the reproduction of the pest in summer and autumn. In the last 20 years, the medfly has spread to more northern areas and has been detected at higher altitudes. There are 25 host plant species that have been reported as host plants of the medfly in this area. Considering the extremely high invasiveness of the medfly and its wide distribution in several areas of the Balkan Peninsula with different climatic conditions, we can assume that it is adapting to new climatic conditions and infesting new host plants. The Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann 1824; Diptera, Tephritidae), is considered one of the most important pests, infesting more than 300 species of fresh fruit and vegetables worldwide. The medfly is an important invasive species, which has spread from the eastern part of sub-Saharan Africa to all of the world's continents in recent centuries. Currently, the medfly is expanding its geographical range to cooler, temperate areas of the world, including northern areas of Mediterranean countries and continental areas of Central Europe. We collected and analysed all the available information, including in historical records, on the phenology of the medfly in the Balkan Peninsula, to map and understand the path of invasion and spread dynamics on the northern Mediterranean coast and in Central Europe. The medfly was first recorded in the Balkan Peninsula in 1915, in the Aegean area on the island of Aigina, followed by a few records on its presence in the Peloponnese in the early 1930s and throughout the Adriatic coastal area in the 1950s; it was first detected on the Croatian coast in 1947. By 2010, the medfly had been detected along the entire Ionian coast, while the first record of its presence on the Balkan coast of the Black Sea was made in 2005. Since 2000 to date, there has been a significant increase in the frequency of medfly detections in the interior of the Balkan Peninsula, including occasional detections in areas with unfavourable climatic conditions for overwintering, which seems to be favourable for reproduction during the summer and lead to significant infestation of late ripening fruits (late summer and autumn). In the last 20 years, the medfly has spread to more northerly areas (43 to 45 degrees latitude) and has been detected at higher altitudes (>200 to 600 m). Along the Balkan Peninsula, the infestation of fruits from 25 host plant species, from 14 genera and 10 plant families, has been reported. Considering the extremely high invasiveness of the medfly and its wide distribution in several Balkan regions with different climatic conditions, we can assume that it is adapting to new climatic conditions and infesting new host plants. [ABSTRACT FROM AUTHOR]

Simple Summary: This study assessed the genetic diversity of carambola fruit fly populations in Brazil and Suriname, comparing them with Asian populations. The results suggest that Indonesia is the likely source of this species' introduction into South America, and the low genetic diversity supports the hypothesis of a recent introduction of a single lineage. Additionally, our findings may be useful for invasion risk assessment and for establishing priorities in the control and management of this important pest species. The carambola fruit fly, Bactrocera carambolae Drew & Hancock, is native to Southeast Asia, infests about 150 plant species, and is considered a quarantine pest insect in several regions of the world. Bactrocera carambolae has invaded Suriname, French Guyana, and northern Brazil. In Brazil, it was first recorded in 1996 and has been restricted to the states of Amapá and Roraima due to official control efforts of the Ministry of Agriculture and Food Supply (Ministério da Agricultura e Pecuária—MAPA). This is the first study to estimate the genetic structure and diversity of South American populations of B. carambolae. A total of 116 individuals from 11 localities in Brazil and 7 localities in Suriname were analyzed. Additional sequences available at GenBank from Indonesia (Lampung) and Thailand (San Pa Tong and Muang District) were also used in the analysis. We sequenced a fragment of the mitochondrial gene cytochrome oxidase subunit I. A total of 35 haplotypes were found. Haplotypes from Indonesia were closest to the haplotypes from South America, separated only by a few mutational steps. This suggests that Indonesia is the likely source for the introduction of B. carambolae into South America. The Southeast Asian populations appeared as the most ancestral group in the phylogenetic trees. The high similarity and sharing of several haplotypes among populations within South America indicate a lack of genetic structure. The mismatch distribution and neutrality tests suggest that South American populations have undergone a rapid growth and expansion following a single founder event. The low genetic diversity and the population expansion evidenced by the neutrality tests lend support to the hypothesis of a recent introduction of a single lineage of the carambola fruit fly into South America. [ABSTRACT FROM AUTHOR]

The pumpkin fruit fly, Bactrocera tau (Walker) (Diptera: Tephritidae) is one of the most serious insect pests of fruits, vegetables and nuts over the world due to its polyphagous nature and high reproductive rate. To gain insight into their sensory system, the external morphology, typology, density, and distribution of sensilla on full bodies of both adult male and female B. tau were observed using a scanning electron microscope. The observed sensilla showed organ as well as sex specific differences. Seven previously described sensilla (two non-olfactory, five olfactory with 17 subtypes) and a new sensillum named as "branched sensilla" (two subtypes) were identified and observed on the different body parts. Olfactory sensilla named as sensilla trichodea and sensilla basiconica were reported on the compound eyes for the first time. Majority of the olfactory sensilla were reported on the head appendages. The presence of species-specific as well as sex-specific branched sensilla in females showed different typology patterns of sensilla. The potential roles of observed sensilla were hypothesized through comparative analysis with prior research. The current findings can provide a reference for understanding the diversity of various olfactory and non-olfactory sensilla in B. tau as well as sex-specific morphological differences and functions of various body parts; thereby, aiding in the development of precise methods for regulating and managing insect behaviour. [ABSTRACT FROM AUTHOR]

The recent discovery of a sesquiterpene, β-caryophyllene (CP) as a male attractant of the guava fruit fly, Bactrocera correcta (Bezzi) (Diptera: Tephritidae) prompted investigations into the attractancy of CP to the Oriental fruit fly, B. dorsalis (Hendel). This is because males of both species of fruit flies are attracted to, and feed on a phenylpropanoid compound, methyl eugenol (ME). Although CP was a more potent attractant than ME for B. correcta, it is not known if males of B. dorsalis are also attracted to CP. The possible attraction of B. dorsalis to CP as a sesquiterpene may indicate its wide host range through its attraction to different groups of plant volatiles i.e., phenylpropanoids and sesquiterpenes. In this paper, we report that males of B. dorsalis were also attracted to, and feed on CP. Subsequently, we conducted a probit regression analysis to determine the quantal response of sexually mature male flies that were attracted to CP in cage bioassays. Therefore, as a measure of male B. dorsalis' sensitivity of CP, the median dose of CP required to elicit a positive response in 50% of the tested B. dorsalis population (ED50) was calculated as 3.7 mg. This value was over 10,000x higher than known ED50 of B. dorsalis' male attraction ME (between 171 and 268 ng). We propose that the attraction of male B. dorsalis flies to CP was much weaker than to ME. Further, we suggest that in any fruit fly surveillance and monitoring programme, application of lures must consider the specificity and potency of each compound to target fruit fly species. The probit regression analysis of male fly quantal response to lure offers such information. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome of Sphaeniscus atilius was characterized and annotated in this study. The mitogenome was 16,854 bp in length and encoded 37 typical mitochondrial genes, including 13 protein-coding genes, 22 tRNA genes, 2 ribosomal RNA genes, and 1 control regions. The total length of the 13 PCGs was 11,140 bp, and the AT content was 79.8%. There were five types of start codons, ATT (nad2, nad3, nad5, and nad6), ATG (cox2, cox3, atp6, nad4, nad4l, and cob), CGA (cox1), as well as ATC (atp8) and ATA (nad1). Most of the PCGs had typical TAA stop codons, except nad5 which terminated with incomplete forms T-. Ile, Phe, Leu and Asn were the most frequently used amino acids in mitochondrial PCGs. Most tRNA genes could be folded into the typical cloverleaf structure, except trnS1 and trnT which lacked the dihydrouridine (DHU) and TΨC arms, respectively. Phylogenetic analyses based on 13 protein-coding genes among the available sequenced species of family Tephritidae by maximum likelihood and bayesian inference methods suggested the genus relationship of Tephritidae: ((Bactrocera, Dacus, Zeugodacus), Felderimyia, Anastrepha), (Acrotaeniostola, (Neoceratitis, Ceratitis), Euleia, Rivellia), (Procecidochares, (Tephritis, Sphaenisscus))))). Our results presented the first mitogenome from Sphaeniscus and provide insights into the species identification, taxonomy and phylogeny of S. atilius. [ABSTRACT FROM AUTHOR]

Insects that evolved in mesic regions may have difficulty establishing in xeric regions. Rhagoletis pomonella (Walsh) (Diptera: Tephritidae) was introduced into drier western North America from mesic eastern North America while Rhagoletis indifferens Curran is native to western North America. Here, we predicted that R. indifferens survives water deprivation longer than R. pomonella, as R. indifferens is more abundant than R. pomonella in dry central Washington (WA) State, USA. Sweet and bitter cherry-origin R. indifferens and apple- and hawthorn-origin R. pomonella from xeric central or mesic western WA were provided water throughout or were water-deprived at 2–4 and 14–18 d old and held at 20°C or 30/31°C and daily survival recorded. At 20°C and 30°C, western WA apple-origin R. pomonella provided water survived longer than sweet cherry-origin R. indifferens. When water-deprived, however, 2–4 d old R. indifferens, although smaller, survived significantly longer than western WA apple-origin R. pomonella of the same age. This was also generally true for 14–18 d old flies, although differences were less often significant. Central WA large-thorn hawthorn-origin R. pomonella survived water deprivation significantly longer than western WA apple-origin R. pomonella, and as long as R. indifferens. Water-deprived flies of both species survived longer at 20°C than 30/31°C. Survival analyses suggest that low water availability rather than high temperature contributes to lower R. pomonella than R. indifferens abundances in central WA, with R. pomonella populations in that region differing from western WA R. pomonella with respect to tolerance of xeric climates. [ABSTRACT FROM AUTHOR]

Fruit volatiles play a crucial role in the host localization by the oriental fruit fly, Bactrocera dorsalis Hendel (Diptera: Tephritidae). This study focused on identifying the fruit volatiles from Sanyue plum and Sanhua plum (Prunus salicina Lindl.), which are 2 varieties of the same species, and examined their impact on the behavior of B. dorsalis by using a Y-olfactometer. A total of 35 and 54 volatiles from Sanyue plum and Sanhua plum were identified, respectively. Among these, 23 volatiles elicited electroantennographic (EAG) responses by B. dorsalis adults, showing concentration-dependent effects in males and females. Ethyl butyrate, butyl acetate, butyl hexanoate, ethyl caproate, ethyl hexanoate, and hexyl acetate significantly attracted B. dorsalis compared to liquid paraffin, while nonaldehyde was avoided. There was no significant difference in the behavioral responses of both sexes to sorbitol esters, hexyl isobutyrate, and 1-tetradecene compared with the control liquid paraffin group. Interestingly, (3 Z)-C-3-hexenyl acetate significantly attracted females, but not males. The above findings suggest that plum fruit volatiles are likely to facilitate the localization of host fruit by B. dorsalis adults and may even aid in mate-finding. This study opens up new avenues for exploring novel plant-based attractants that might be of value for the integrated management of B. dorsalis. [ABSTRACT FROM AUTHOR]

tFirst records of Tephritidae spp. (Diptera) for selected areas of European Russia are presented: Chaetostomella rossica Hendel, 1927 for Ulyanovsk and Samara regions, Euleia rotundiventris (Fallén, 1814) for Ulyanovsk Region and Mordovia, Urophora stylata (Fabricius, 1775) for Samara Region and Mordovia. Tephritis neesii (Meigen, 1830) is recorded from Armenia and Transcaucasia for the frst time. Two species of Asteraceae from Armenia, Centaurea takhtajanii Gabrieljan et Tonjan and Psephellus pulcherrimus (Willd.) Wagenitz, were identifed as new host plants of Acanthiophilus helianthi (Rossi, 1794) and Terellia odontolophi Korneyev, 1993, respectively

Abstract The olive fly, Bactrocera oleae (Rossi, 1790), is the major insect pest of olives attacking both cultivated and wild olive. Bactrocera oleae carries a primary and vertically transmitted symbiont, the bacterium Candidatus Erwinia dacicola. As any primary symbiont, it plays an important role in the reproduction and lifespan of the fly. The genetic 16S rRNA diversity of the primary symbiont and the mitochondrial haplotype variation of the insect host were simultaneously examined in 54 olive fly populations. The aim was to unravel the biogeographic patterns of this economically relevant host-bacteria interaction across a wide distribution area. Three symbiont haplotypes were identified. The primary symbiont showed a lower haplotype diversity than that of its host, a characteristic indicative of a long-term interaction. A significant genetic and geographic association between host and primary symbiont was observed, with an East-West genetic differentiation pattern in the Mediterranean basin, coinciding with the historical genetic distribution of the olive tree. The study shows promise, informing and aiding the development of future tools for the control of the olive fly.

Here, we present novel high quality genome assemblies for five invasive tephritid species of agricultural concern: Ceratitis capitata, C. quilicii, C. rosa, Zeugodacus cucurbitae and Bactrocera zonata (read depths between 65 and 78x). Three assemblies ( C. capitata, C. quilicii and Z. cucurbitae) were scaffolded with chromosome conformation data and annotated using RNAseq reads. For some species this is the first reference genome available ( B. zonata, C. quilicii and C. rosa), for others we have published improved annotated genomes ( C. capitata and Z. cucurbitae). Together, the new references provide an important resource to advance research on genetic techniques for population control, develop rapid species identification methods, and explore eco-evolutionary studies.

Environmental cues that predict increased risk of herbivory can prime plant defenses; however, few studies have explored how such cues elicit broader plant responses, including potential effects on plant growth and other resource allocations that may affect tolerance to herbivore damage. We exposed goldenrod plants (Solidago altissima) to varying concentrations of the putative sex pheromone of a gall‐inducing herbivore, which has previously been implicated in defense priming. In experiments with two plant genotypes and three herbivore populations, any level of exposure to the pheromone enhanced tolerance of galling, rescuing flower production to levels observed for ungalled plants. Exposure to low doses of the pheromone elicited greater resistance to galling than exposure to high doses, with unexposed plants exhibiting intermediate resistance, suggesting a nonlinear relationship between exposure and defense priming. These findings suggest plant responses to environmental cues associated with biotic stressors are broader and more complex than previously appreciated. [ABSTRACT FROM AUTHOR]

Anastrepha ludens (Mexican fruit-fly) is a highly polyphagous fruit fly species (Tephritidae) attacking wild and commercial fruit from Mexico to Panama. Here we report on a recent habitat and host range expansion as A. ludens lately started to attack apples (Malus domestica) in Mexico, a phenomenon likely influenced by global warming. We document natural infestations in apple-growing regions in the States of Nuevo León and Hidalgo, Mexico where A. ludens has started to attack the cultivars 'Golden Delicious', 'Rayada' and 'Criolla'. No infestations were found in the apple-growing region of Zacatlán, Puebla. To determine apple cultivar susceptibility to the attack of this emerging pest, we ran forced infestation assays in enclosed fruit-bearing branches in all three apple-growing regions and studied the metabolome of all fruit. A clear pattern emerged indicating that the cultivar 'Golden Delicious' was the most susceptible, with 'Criolla' exhibiting complete resistance in one location (Puebla). Although A. ludens can develop in this new host, development rates (egg—adult) and adult emergence were affected when compared with the performance in the natural host 'Marsh' grapefruit. Warmer temperatures and specific secondary metabolites of some apple cultivars are likely contributing to the territorial and host expansion of A. ludens. [ABSTRACT FROM AUTHOR]

In insects, aging produces deterioration in physiological and cellular functioning, affecting their reproductive potential. Anastrepha fraterculus and Ceratitis capitata are two fruit fly species where overwintering adults resume their reproductive activity in spring, giving old individuals the possibility of mating with young adults. Most age studies focus on male reproductive capacity; however, we lack information on how the interaction between the ages of both sexes can determine post‐mating processes. Here, we studied sex and age effects on (i) female fecundity and fertility, (ii) failure to leave viable offspring (reproductive failure), and (iii) female remating behavior. We found that young pairs of both species had higher fecundity, but young C. capitata males mated with old females had the lowest fecundity. This suggests that overwintering flies in this species will not substantially contribute to the next generation. We also found in C. capitata more prevalent reproductive failure in hetero‐age combinations, which could be due to age recognition between mates, resulting perhaps in differential ejaculate allocation. Copula duration was positively associated with female age, yet it was longer for older A. fraterculus females and shorter for C. capitata females. Female remating was lower when young females mated with old males in C. capitata. This would imply that males perceive young females of "good quality" and thus invest and transfer all the ejaculate possible to ensure the delay of renewal of female receptivity. Aging does not always cause a decline in reproductive potential, which may be important in species that overwinter as adults. Complex interactions between female physiology and male ejaculate senescence can impact postcopulatory behaviors that affect reproductive success for both sexes. [ABSTRACT FROM AUTHOR]

Simple Summary: The oriental fruit fly, Bactrocera dorsalis, pupates in the soil, and the depth at which it pupates influences its susceptibility to natural enemies, which plays a key role in biological control programs. This laboratory study examined the relationship between temperature and pupation depth, showing that even small changes in temperature lead to significant variations in pupation depth. This result suggests that temperature may affect interactions between B. dorsalis and its natural enemies in ways that were previously overlooked. The oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), is a notable agricultural pest that undergoes pupation in the soil. Mortality risk from predation and parasitism decreases as the depth of the pupal location increases from the ground surface, with a one-centimetre increase in depth causing a significant change. Soil properties, such as moisture and hardness, influence pupation depth, but the effect of temperature has not been fully tested. This laboratory study examined whether a biologically important variation in pupation depth (e.g., one centimetre) is caused by naturally experienced temperature variations (20 to 35 °C) in B. dorsalis. The temperature–pupation depth relationship revealed a unimodal pattern, with the deepest pupation occurring at intermediate temperature levels and shallower pupation at the two extreme temperature ranges. Strong quantitative effects were observed, with the highest mean pupation depth of 40.8 mm at 27.5 °C and the lowest mean pupation depth of 15 mm at 35 °C. The observed quantitative effect suggests that temperature can strongly affect pupal mortality from predators and parasitoids by influencing pupation depth. Future studies that reveal the ability of biological control agents to forage underground for pupae at different temperatures are awaited, as this is key information for evaluating the effectiveness of these agents. [ABSTRACT FROM AUTHOR]

Biotic and abiotic factors influence how insects respond to stimuli. This can make it challenging to interpret captures in traps used to monitor pest abundance in management programmes. To address this, the lure response of three pest fruit flies (Diptera: Tephritidae) was evaluated in a semi-field setting with respect to several physiological and environmental factors. Using standardised methods with known fly numbers in field cages, the response to Biolure (food-based lure) was evaluated for Ceratitis capitata, Ceratitis cosyra and Bactrocera dorsalis. Response to the male lures was tested: E.G.O PheroLure for C. capitata and C. cosyra, Trimedlure for C. capitata, and methyl eugenol for B. dorsalis. The physiological variables evaluated were fly age, sex, weight, and total body nutritional composition. The environmental effects of temperature, relative humidity and light intensity were also assessed. Protein-deprived adults responded more strongly to Biolure. The response to Biolure was not sex-specific. Fly age influenced the response of all species to all tested lures. However, this effect was species and lure specific. Temperature was the most influential environmental factor, with response generally increasing with temperature. Lower thresholds for lure response, despite the proximity of responsive flies, range from 12.21 to 22.95 °C depending on the species and lure tested. These results indicate that trapping systems and management activity thresholds must take physiological and environmental variation into account to increase their accuracy. [ABSTRACT FROM AUTHOR]

BACKGROUND: Insecticide resistance among invasive tephritid fruit flies poses a great risk to national food security and has the potential to disrupt quarantine and eradication programs, which rely on the efficacy of Spinosad to prevent widespread establishment in North America. During 2022 to 2023 we surveyed the extent of Spinosad resistance of two key species, oriental fruit fly Bactrocera dorsalis, and melon fly Zeugodacus cucurbitae, from 20 sites across five Hawaiian Islands including Kaua'i, O'ahu, Maui, Molokai and the "Big Island" (Hawai'i). RESULTS: We used topical thoracic applications of eight concentrations of Spinosad ranging from 0.028 to 3.6 mg/mL to evaluate the lethal concentration (LC50 and LC99) required to kill wild‐caught males. Resistance ratios (RR) were calculated by comparing the LC50 of wild flies to laboratory susceptible lines maintained in colony. Our results identified at least two new sites of concern for melon fly resistance on the Big Island, and at least four sites of concern for oriental fruit fly, all of which were located on the Big Island. At these locations RRs were >5. On O'ahu, melon fly RRs were >10. CONCLUSIONS: The persistence of Spinosad resistance is concerning, yet it is a reduction compared to the values reported previously and before changes to Spinosad use recommendations by local extension agents beginning in 2017. For oriental fruit fly, these RR values are the highest levels that have been detected in wild Hawai'i populations. These data suggest that expanded Spinosad reduction and replacement programs are warranted given the ongoing issues with Spinosad resistance in Hawai'i and expansion in the number of species affected. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

The relationship of Bactrocera oleae Rossi with fruit phenolic compound concentration and fruit size was assessed in four Greek cultivars ('Mastoidis', 'Amfissis', 'Kalamon', 'Koroneiki') for two consecutive years. The flies preferred to rest in the foliage of 'Amfissis' and 'Kalamon' rather than 'Koroneiki', regardless of the fruit load. Female adults seemed to prefer 'Amfissis' olives for their offspring development as indicated by the significantly higher alive infestation, higher number and heavier pupae. The concentration of oleuropein, total phenolic compounds, and o-diphenols in the flesh of the fruit seemed to be inversely related to cultivar susceptibility, and this was particularly evident in table olives 'Amfissis', which presented a low concentration of phenolic compounds, but a high fly infestation. The role of anthocyanins was also important, as 'Kalamon' with low oleuropein content, but high anthocyanin one, presented intermediate infestation. Likewise, 'Koroneiki' with the smallest fruit weight and intermediate phenolic concentration, exhibited low fly infestation. It seems that phenolic compounds play a significant role in the susceptibility or tolerance of a cultivar to fly attack while other factors, biochemical and/or physiological ones, can also contribute. [ABSTRACT FROM AUTHOR]

Plant galls are thought to evolve under natural selection as extended phenotypes of the insects that induce them. An evolutionary response to selection requires that the phenotypic variance in the selected trait be caused by underlying heritable genetic variance. We used a one-generation artificial selection experiment to verify heritable variation in the size of the gall induced by the tephritid Eurosta solidaginis (Fitch, 1855) on the stems of tall goldenrod, Solidago altissima L. (Asteraceae). Previous work under greenhouse conditions demonstrated that gall size is a heritable trait of species of EurostaLoew, 1873, but two questions remain. Foremost, is the genetic signal that is evident in a uniform, controlled environment still detectable in heterogenous natural environments? And secondarily, since galls initiated later in the season are known to grow to a smaller size, is genetic variance in gall size attributable to genetic variance in Eurosta phenology? We imposed upward and downward selection on size by populating isolated goldenrod patches with parental flies emerging from either large diameter (> 24 mm) or small diameter (< 17 mm) or galls. Galls produced by the offspring in upward-selected patches were ~19% larger than those in downward sites. While gall size declined with later initiation dates, there was no evidence that the upward- and downward-selected sites varied in either oviposition date or gall initiation date; thus, genetic variance in gall size is not rooted in genetic variance for phenology. Our results support the notion that while the gall is plant tissue, it develops under the influence of the insect's genotype, and thus can evolve as the gallmaker's extended phenotype. [ABSTRACT FROM AUTHOR]

In order to explore the efficient green prevention and control methods for Tephritidae, three kinds of common food attractants for Tephritidae on the market were selected, which were Tephritidae bait spindle (food attractant 1), the sugar-vinegar liquid (sugar: vinegar: wine: water = 5: 3: 2: 10) (food attractant 2), and Tephritidae concentrated bait (food attractant 3). The trapping effects of different species of Tephritidae were tested in the watermelon and luffa planting bases, thus to evaluate their trapping effects on three common species of Tephritidae. The results showed that the three kinds of food attractants for Tephritidae had attractive effects on Bactrocera cucurbitae, Bactrocera minax and Bactrocera dorsalis. However, the trapping effect of the food attractant 3 on the three kinds of Tephritidae was the best. The total number of three kinds of Tephritidae trapped by the food attractant 3 was 2.93 times higher than that by the food attractant 1 and 9.50 times higher than that by the food attractant 2. The trapping amount of female adults by the food attractant 3 and the food attractant 1 was higher than that of male adults. The study screened a food attractant insecticide that had a significant attractive effect on female and male adults, especially on female adults, which met the production needs of fruit growers. [ABSTRACT FROM AUTHOR]

Simple Summary: Bactrocera dorsalis (Hendel) is a notorious horticultural pest. The male annihilation technique (MAT) is a key strategy in the pest management program of B. dorsalis. However, there is currently no method to monitor the effectiveness of MAT in real time. In this study, it was discovered under a microscope that sperms can be detected in the spermathecae and the ventral receptacle of mated B. dorsalis females. Furthermore, sperms are more easily observed in the spermathecae and can be retained there for more than 50 days. Field investigations demonstrated that the proportion of mated females was less than 81.2% in an abandoned mango orchard, while it was reduced to less than 36.4% in another mango orchard where MAT was applied. This indicates that dissecting the spermathecae to observe the presence of sperms is a reliable method to accurately monitor the proportion of mated B. dorsalis females in the fields. This method can be used in real time and accurately assess the control efficiency of MAT in B. dorsalis management. The male annihilation technique (MAT) plays a crucial role in the pest management program of the oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae). However, a suitable method for real-time and accurate assessment of MAT's control efficiency has not been established. Laboratory investigations found that motile sperms can be observed clearly under the microscope when the spermathecae dissected from mated females were torn, and no sperms were found in the spermathecae of virgin females. Furthermore, it was confirmed that sperms can be preserved in the spermathecae for more than 50 days once females have mated. Laboratory results also indicated that proportion of mated females decreased from 100% to 2% when the sex ratio (♀:♂) was increased from 1:1 to 100:1. Further observation revealed that there were no significant differences in the superficial area of the ovary or spermatheca between mated females and virgin females. Field investigations revealed that the proportion of mated females (PMF) could reach 81.2% in abandoned mango orchards, whereas the PMF was less than 36.4% in mango orchards where MAT was applied. This indicates that the PMF of the field population can be determined by examining the presence of sperms in the spermathecae. Therefore, we suggest that this method can be used to monitor the control efficiency when MAT is used in the field. [ABSTRACT FROM AUTHOR]

Certain species of true fruit flies (Diptera: Tephritidae) cause tremendous damage to commercially important fruits and vegetables, and many countries operate continuous trapping programs which rely on male-specific lures such as trimedlure (TML), methyl eugenol (ME), and cue-lure (CL). Traditionally, these attractants have been applied as liquids to cotton wicks inside traps, although this results in high evaporative loss of the lure. Slow-release, polymeric plugs have been widely adopted for TML, but such devices are not widely used for ME or CL. Recent data, however, suggest that ME and CL plugs may be attractive for as long as 12 wk in the field. The present study investigates whether ME and CL plugs weathered for 18 or 24 wk are effective in capturing males of Bactrocera dorsalis (Hendel) and Zeugodacus cucurbitae (Coquillett), respectively. For B. dorsalis , 6 g ME plugs were as effective as the control treatment (fresh liquid on a wick) after 12 wk of weathering but not after 18 or 24 wk. For Z. cucurbitae , 3 g CL plugs were as effective as the control treatment (fresh CL plugs) after 12 and 18 wk of weathering but not after 24 wk. The residual content and release rate of the 2 lures were also measured over time, but, with the exception of the residual content of ME, we did not find a direct correlation between these parameters and numbers of flies captured. [ABSTRACT FROM AUTHOR]

Sterile insect technique (SIT) is a useful strategy for preventing and mitigative establishment of invasive insect species. SIT of the pest tephritid Mediterranean fruit fly, Ceratitis capitata (Wiedemann, 1824) WiedemannWiedemann , has been effective in preventing population establishment in vulnerable agricultural areas of the United States. However, irradiation-induced sterilization can have detrimental impacts resulting in reduced performance metrics. Mediterranean fruit fly males reared for SIT have been shown to have differences in their microbiomes relative to other population sources, which has been postulated to be a factor in how well flies compete with wild conspecifics. To identify baseline performance metrics on the effects of irradiation on the gut microbiome of mass-reared flies in Hawai'i, a study was performed to assess performance metrics and microbiome (bacterial 16S rRNA) variation across multiple timepoints. Mediterranean fruit fly pupae were selected from mass-reared trays intended for release, and paired samples were either irradiated or remained as controls and transported to the laboratory for evaluation. Irradiated flies exhibited fewer successful fliers, more rapid mortality rates, and were less active relative to control nonirradiated flies. Contrary to initial expectations, irradiation did not exert substantial impacts on the composition or diversity of bacterial reads. Samples were primarily comprised of sequences classified as Klebsiella and there were low levels of both read and taxonomic diversity relative to other 16S surveys of medfly. Although this study does not demonstrate a strong effect of irradiation alone on the Mediterranean fruit fly microbiome, there are several explanations for this discrepancy. [ABSTRACT FROM AUTHOR]

Zeugodacus tau (Walker) (Diptera: Tephritidae) is an important agricultural pest currently managed primarily through the application of insecticides due to limited control strategies. Bait station devices are target specific and have emerged as a behaviorally based alternative to traditional insecticide sprays for managing Z. tau. In this study, we designed a bait station by integrating female-biased olfactory, visual, and gustatory elements, and a killing agent in a wax-matrix. Our results showed that the wax-matrix integrated with spinetoram showed the highest toxicity to immature and mature Z. tau females. Furthermore, the color and shape of the spinetoram bait station significantly influenced its attractiveness and toxicity to female Z. tau. Green sausage-shaped exteriors were the most effective color and shape examined. Subsequent experiments showed a length-dependent effect on mortality and visiting frequencies of Z. tau females when the bait stations were 9–13 cm long. The addition of the olfactory stimulus of 5% ammonium acetate to the bait station attracted a higher number of mature Z. tau females than the control. The killing efficacy of the weathered bait station was similar to that of the fresh station within an 8-week period (over 794 mm of rainfall). The bait station developed herein would provide new insight into the attract-and-kill strategy for Z. tau and alleviate the pressure of the actual management program for this pest. [ABSTRACT FROM AUTHOR]

Insects collected in dry traps can degrade rapidly, especially in warm, humid environments where many biodiversity and biosecurity surveillance activities are undertaken. Degradation can severely impact diagnostics, as trap catches can become difficult to identify to species level using morphological characters or, of increasing importance, molecular approaches. This is especially problematic for biosecurity surveillance of exotic tephritid fruit flies, where diagnostics are heavily reliant on morphological characters. We tested the effects of differing temperature and humidity conditions on mock samples of tephritid fruit flies in a controlled environment and compared our results to field trap catches. DNA degradation was quantified using real-time PCR assays, including one assay newly developed and tested here. We observed a correlation between increasing DNA degradation and increasing temperature and humidity. The greatest DNA degradation occurred under combined high humidity (90% relative humidity) and constant high temperature (35 °C). Unexpectedly, fluctuating temperature did not have a significant impact on DNA. Other factors, such as trap design, time in the field, and rainfall, did not significantly correlate with DNA quality across the field samples tested. When plotted against mock samples, field samples clustered together, with no clear pattern or predictability regarding the quantity of DNA preserved, indicating other untested environmental variables may be at play. Predictably, increased exposure time was found to have a detrimental effect on DNA quality for all treatments. These findings will improve the delivery of surveillance activities through the implementation of shorter trap clearance timeframes and improved trap designs and procedures. [ABSTRACT FROM AUTHOR]

Fruit flies attack numerous crops, including cherry tomatoes (Solanum lycopersicum var. cerasiforme). The potential presence of the immature stages of fruit fly species inside tomatoes during export hinders their international market access. Therefore, phytosanitary treatment must be performed before export to prevent fruit fly species from entering countries where they are not naturally found. We developed a phytosanitary cold disinfestation treatment protocol to eliminate oriental fruit fly (Bactrocera dorsalis Hendel), melon fly (Zeugodacus cucurbitae Coquillett), and pumpkin fruit fly (Zeugodacus tau Walker) concealed inside cherry tomatoes without causing critical damage to the fruit. We determined that the third instar of Z. cucurbitae exhibited the highest cold tolerance among the various development stages of the three fruit fly species. Thus, we performed a small-scale disinfestation test on Z. cucurbitae in two cultivars of tomato. We achieved complete disinfestation after 15 days of cold treatment at 1°C–1.5°C. The confirmatory test revealed the elimination of more than 80,000 treated third instar of Z. cucurbitae in each tomato variety. The developed phytosanitary cold treatment allows the tomatoes to retain their commercial value. This study provides a standard phytosanitary cold treatment protocol for cherry tomatoes, ensuring the disinfestation of fruit flies before their export to international markets. [ABSTRACT FROM AUTHOR]

The Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann), one of the most important invasive pests of fresh fruits and vegetables from the coastal Mediterranean habitats, is expanding its current geographic distribution to cooler more temperate areas of Europe. Every year since 2010 the fly is detected in the area of Vienna, Austria. However, whether it can establish permanent populations is not known. In this current paper, the capacity of C. capitata to overwinter in Vienna, Austria (48.1° northern latitude) was studied over 2 consecutive winter seasons (2020–2022). Overwintering trials with different life stages (larva, pupa, and adult) of C. capitata were performed in the open field and in the protected environment of a basement without a heating system. Control flies were kept under constant conditions in a climate chamber (25 °C, 60% RH, 14:10 L:D). Our data showed that no life stage of the Mediterranean fruit fly was able to survive the Austrian winter in the open field. However, in the protected environment C. capitata outlived the winter months in all studied life stages at least in small numbers and several surviving females were able to lay eggs at the time of the following fruiting season. Implications of these findings for the ongoing geographic range expansion of the pest in temperate European countries are discussed. [ABSTRACT FROM AUTHOR]

The olive fly, Bactrocera oleae (Rossi, 1790), is the major insect pest of olives attacking both cultivated and wild olive. Bactrocera oleae carries a primary and vertically transmitted symbiont, the bacterium Candidatus Erwinia dacicola. As any primary symbiont, it plays an important role in the reproduction and lifespan of the fly. The genetic 16S rRNA diversity of the primary symbiont and the mitochondrial haplotype variation of the insect host were simultaneously examined in 54 olive fly populations. The aim was to unravel the biogeographic patterns of this economically relevant host-bacteria interaction across a wide distribution area. Three symbiont haplotypes were identified. The primary symbiont showed a lower haplotype diversity than that of its host, a characteristic indicative of a long-term interaction. A significant genetic and geographic association between host and primary symbiont was observed, with an East-West genetic differentiation pattern in the Mediterranean basin, coinciding with the historical genetic distribution of the olive tree. The study shows promise, informing and aiding the development of future tools for the control of the olive fly. [ABSTRACT FROM AUTHOR]

The peach fruit fly (PFF), Bactrocera zonata (Saunders, 1841) (Diptera: Tephritidae) is a destructive polyphagous pest infesting a lot of horticultural fruits and some vegetables. At Damietta governorate, Egypt, the present study aimed to maximize the efficiency of the male annihilation technique (MAT) by estimating different types of blocks (as dispensers) impregnated with different doses (3, 6, and 9 cm³/block) of methyl eugenol to attract PFF males in guava orchards. Two different types of blocks [Hard woodpulpluff (HWF) and plant fibers] were selected for the present study. These blocks were tested as uncovered blocks and covered with aluminum polyethylene polyester. The study was carried out over eight successive weeks (from 27th September to 15th November 2023). The obtained results showed that the covered HWF blocks impregnated with the dose of 9 cm³/block were superior in attracting PFF males all over the investigation period followed by uncovered plant fibers, uncovered HWF, and covered plant fibers' blocks. There were positive relationships between the captured PFF males and the concentration of methyl eugenol. The covered HWF blocks were relatively more stable against elapsed time in comparison with uncovered HWF or plant fibers' blocks. In conclusion, the covered HWF blocks were more effective dispensers all over eight weeks for methyl eugenol to attract PFF males in comparison with uncovered HWF blocks and plant fibers. [ABSTRACT FROM AUTHOR]

Simple Summary: The olive fruit fly, Bactrocera oleae Gmelin (Diptera: Tephritidae), is one of the most harmful olive pests in Mediterranean countries and worldwide, and its control is mainly based on chemical insecticides. Volatile organic compounds (VOCs) emitted from the olive fruit affect the physiology and behavior of the olive fly and could be an effective tool for its control. In this study, we determined the effect of certain olive fruit VOCs on attraction to olives, egg production, and longevity of B. oleae females, under a series of temperatures. The results show that the exposure of female flies to certain VOCs either increased or decreased the number of landings on the olives, egg production, and longevity. These findings are poised to advance our understanding of the role of olive fruit volatiles on olive fly behavior and may contribute to the improvement of bait or repellent products for its control. Females of the olive fruit fly Bactrocera oleae use various contact and volatile plant stimuli to find olive fruits and lay their eggs on them. We detected certain volatile organic compounds (VOCs) emitted from the olive fruit and studied their effect on female landings on olive fruits, egg production, and longevity under a series of different temperatures from 15 °C to 35 °C. When female flies were maintained at temperatures from 17 °C to 30 °C and exposed to different fruit VOCs either increased or decreased, depending on the substance tested, their landings on olives, egg production, and longevity. Temperature significantly affected the females' responses to fruit VOCs. The highest responses of the flies to fruit VOCs were observed at 30 °C, except for longevity. By contrast, at 15 °C or 35 °C, the flies did not show any response to VOCs. Our results may contribute to a better understanding of the olive fly positive or negative responses to fruit VOCs and the improvement of its control. [ABSTRACT FROM AUTHOR]

Simple Summary: Bactrocera dorsalis is an invasive fruit fly pest that causes significant damage to vegetables and fruits in Southern China. Insecticides have been used for many years to effectively control B. dorsalis, leading to the development of varying degrees of resistance to a wide range of insecticides. In this study, we monitored the resistance of 11 different populations of B. dorsalis to seven commonly used insecticides in Southern China from 2010 to 2013 and followed up in 2023. We found that the resistance dynamics to each of the seven insecticides were unique. Antibiotic insecticides showed the most rapid increase in resistance, while organophosphates exhibited a decreasing trend. These findings will aid in the development of more effective resistance management strategies to improve the efficiency and sustainability of agricultural pest management. Bactrocera dorsalis is a highly invasive and destructive pest distributed worldwide. Chemical insecticides remain the primary measure for their control; however, this species has already developed resistance to several insecticides. In recent years, there have been several reports of monitoring B. dorsalis resistance in China, but continuous monitoring results are lacking and do not even span a decade. In this study, we monitored the dynamics of resistance to seven insecticides among 11 geographically distinct Chinese populations of B. dorsalis (2010–2013; follow-up in 2023). The 11 populations were found to adapt rapidly to antibiotic insecticides (spinosad, emamectin benzoate, and avermectin), reaching high levels of insecticide resistance in several areas. Overall, a decreasing trend in resistance to organophosphorus insecticides (chlorpyrifos and trichlorfon) was observed, whereas pyrethroid (beta-cypermethrin and cyhalothrin) resistance trends were observed to both increase and decrease. The monitoring of field resistance among different B. dorsalis populations over the duration of this study is important for improving the efficiency and sustainability of agricultural pest management, and the results provide a scientific basis for the development of more effective resistance management strategies. [ABSTRACT FROM AUTHOR]

Among 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). [ABSTRACT FROM AUTHOR]

Walnut orchards face challenges from various pests that compromises fruit quality. The Walnut Husk Fly (WHF), Rhagoletis completa Cresson (Diptera: Tephritidae), which infests the Green Walnut Husk (GWH), is one of them. The dietary requirements of WHF larvae, as well as the nutritional information regarding the GWH are scarce, affecting the ability to fully rear this species under laboratory conditions for research purposes. In this study, we analysed the content in macronutrients, inorganics, and vitamins, and the profiles of free sugars, amino acids, fatty acids, and sterols of GWH from Juglans regia L. (cv. 'Franquette'). These findings will serve as valuable guidance for the development of larval diets in WHF rearing. [ABSTRACT FROM AUTHOR]

The invasive spread of the Bactrocera dorsalis (Hendel), (Diptera, Tephritidae) (the oriental fruit fly), is intensifying globally. After sporadic interceptions in Europe, the first field findings occurred in Italy in 2018-2019. Despite a record-free period from 2020 to 2021, catches in Campania surged from June 2022 onwards. In response, a series of research activities began in Campania, aiming to delineate the infested zone, evaluate dispersion, assess population dynamics, identify the epicenter, and determine prevalent host fruits. Over 250 traps of various types, baited with diverse attractants, along with fruit samplings, led to the capture of the first B. dorsalis females and the identification of the first active infestation in Europe during the summer of 2022. Results reveal a rapid increase in captures from June 2022 to January 2023, with over 3,000 adults captured, reaching the peak in October. The expansion of the infested zone reached 48.24 km2, indicating a localized hotspot. Active infestations primarily occurred in specific locations, with Citrus spp. being the most frequently infested fruits. The sex ratio of captured specimens indicates a bias towards males, particularly due to the lure used. The study identifies a narrow 14.04 km2 area, concentrating 97.4% of catches, as the probable epicenter. Specific anthropized localities play a crucial role in sustaining the population. Bactrocera dorsalis specimens exhibited a potential movement range of about 7 km, but the movement of infested fruits can greatly expand this range. The high number of recorded catches suggests the existence of a substantial nucleus of individuals, possibly facilitating the acclimatization of the species in Italy. [ABSTRACT FROM AUTHOR]

Oriental fruit fly, Bactrocera dorsalis (Diptera: Tephritidae), is an infamous invasive pest species with a broad host range. The pest has spread to most territories worldwide in the last decades, posing an increasing threat to global fruit and vegetable production. Here, we reviewed the current knowledge, control methods and prospects of Integrated Pest Management (IPM) strategies against B. dorsalis based on a survey on the pest status, damages and current practices conducted in the Asia region. The outcome of the survey pointed to B. dorsalis as a major concern as it causes heavy damage in most of the participating countries. Current IPM strategies involve multiple control tactics, but often with over reliance on chemical pesticides. Behaviour-based monitoring and control measures are commonly employed in this region because of ease-of-use and cost-effectiveness, which serve as the key component of the IPM strategies. The sterile insect technique application, though environmental-friendly, sustainable and compatible with IPM, is limited because of high operational cost, ineffective government policy and low social acceptance. Public knowledge and technology transfer, training and hands-on guidance, relevant stakeholder community participation, acceptance and cooperation, are the key levers for sustainable and successful IPM against B. dorsalis. More initiatives and research efforts for developing non-chemical control tactics and biopesticides will optimize the existing IPM strategies. Lastly, effective quarantine and phytosanitary measures towards better border biosecurity should be taken to intercept and curtail the risk of B. dorsalis expanding its current geographical boundary in the face of global climate change. [ABSTRACT FROM AUTHOR]

Numerous insects are attracted to low levels of ammonia, utilizing it as a cue to locate food sources. The Ammonium Transporter (Amt), a highly conserved, atypical olfactory receptor, has been shown to mediate the detection of ammonia in insects. While the attraction of Tephritidae to ammonia is well established, knowledge about the Amt in this family is limited. The species Bactrocera dorsalis (Hendel 1912), Bactrocera cucurbitae (Coquillett 1899), Bactrocera correcta Bezzi 1916 and Bactrocera tau (Walker 1849), which are common agricultural pests within Tephritidae, exhibit numerous ecological similarities, offering a solid foundation for studying Amt characteristics in this family. In this study, we elucidated the sequences, evolutionary relationships, and expression patterns of Amt in these four species. The results indicated that these Amts share the same open reading frame, containing 1770 bp that encode a protein of 589 amino acid residues. These Amt proteins exhibit the typical structural characteristics of Amts, including an 11-transmembrane domain with an extracellular N-terminus and an intracellular C-terminus. They also have the ability to form trimers in the membrane. Additionally, they contain three conserved amino acid residues essential for ammonia transport: A189, H195, and H352. Phylogenetic and expression pattern analyses showed that they are highly conserved in Diptera and are significantly expressed in antennae. This study is the first report characterizing the Amt gene in four Tephritidae species. These findings provide a foundation for further exploration into the roles of these genes in their particular biological contexts. [ABSTRACT FROM AUTHOR]

BACKGROUND: The melon fly, Zeugodacus cucurbitae (Coquillett), is an invasive Tephritidae pest with robust fertility. The male accessory glands (MAGs) form a vital organ that ensures insect reproductive efficiency. Most of the secreted proteins by MAGs exhibit a male bias expression. Takeout, one of these proteins, is abundantly present in the MAGs of many insects. RESULTS: In this study, we identified 32 takeout genes in Z. cucurbitae. The phylogenetic analysis and multiple sequence alignment results showed that Zctakeout1 is the most related homolog to the MAGs‐specific takeout in Tephritidae. The real‐time quantitative PCR results showed that Zctakeout1 was exclusively expressed in the male adult stage, and its expression level gradually increased with the increase in age and then remained stable at the sexually matured stage. The distribution among tissues demonstrated the specific expression of Zctakeout1 in the MAGs, and fluorescence immunohistochemical results confirmed the presence of Zctakeout1 in close proximity to binuclear cells of the mesoderm epidermal MAGs. In continuation, CRISPR/Cas9‐mediated genome editing was employed, resulting in successfully generating a homozygous strain with an +8 bp insertion. The mating experiments with the Zctakeout1−/− males resulted in significant reductions in both the mating rate and egg production of females. CONCLUSION: These findings prove that the MAGs‐specific Zctakeout1 is essential in regulating fecundity in female Z. cucurbitae fruit flies. Our data suggests its utilization in future essential insect‐specific gene‐directed sterility insect technique (SIT) by the genetic manipulation to keep these important Tephritidae populations under control. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The olive fruit fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae), causes significant damage to olive crops worldwide. However, the factors affecting its survival under water deprivation have not been studied yet. In this study, the water deprivation resistance of male and female olive fruit flies was measured at three ages in virgin and mated adults fed either a full or a restricted diet. The experiments (24 treatments) were conducted under constant laboratory conditions, using insects collected in the wild and reared on olives. Additionally, a baseline experiment was conducted to provide data on the insects' life expectancy under no-stress conditions. Our findings revealed that males showed much less resistance under water deprivation compared to females. Younger adults endured for longer than older ones, and adults fed a restricted diet endured water deprivation longer than those fed a full diet. Our results suggest that during periods of water scarcity, releasing sterile males is most effective, because the wild male population decreases. Since females of reproductive age are more resistant, this should ensure a higher number of matings with sterile males. These findings can be used to formulate improved pest control strategies that enhance olive product quality while relying less on insecticides. [ABSTRACT FROM AUTHOR]

The solanum fruit fly Bactrocera latifrons (Diptera: Tephritidae) is an invasive alien insect that causes huge economic losses to pepper and other solanaceous plant industries. It is mainly distributed in South and Southeast Asia, SW Europe, Western USA, and in some African countries. However, the potential global geographical distribution of B. latifrons is unknown. Therefore, in this study, based on the current (1981–2010) and future (2040–2059) climatic scenarios determined using the CNRM-CM5, Access1.0, GFDL-ESM-2M, and NorESM1-M models, we used a species distribution model (CLIMEX 4.0) to project the potential global geographic distribution of B. latifrons to prevent further invasion and harm. In the current climate scenario, South America (1286.06 × 104 km2), Africa (1435.47 × 104 km2), and Oceania (410.66 × 104 km2) have the largest proportions of suitable land areas for B. latifrons colonization. Under all four future climate models, the global potential suitable area for Bactrocera latifrons is projected to decrease and shift towards higher latitudes. This study provides an important baseline upon which researchers, quarantine personnel, and governments can develop the appropriate control strategies against B. latifrons. [ABSTRACT FROM AUTHOR]

Tephritid fruit fly pests pose an increasing threat to the agricultural industry due to their global dispersion and a highly invasive nature. Here we showcase the feasibility of an early-detection SEPARATOR sex sorting approach through using the non-model Tephritid pest, Ceratitis capitata. This system relies on female-only fluorescent marker expression, accomplished through the use of a sex-specific intron of the highly-conserved transformer gene from C. capitata and Anastrepha ludens. The herein characterized strains have 100% desired phenotype outcomes, allowing accurate male-female separation during early development. Overall, we describe an antibiotic and temperature-independent sex-sorting system in C. capitata, which, moving forward, may be implemented in other non-model Tephritid pest species. This strategy can facilitate the establishment of genetic sexing systems with endogenous elements exclusively, which, on a wider scale, can improve pest population control strategies like sterile insect technique.