Mediterranean Fruit Fly Ceratitis Capitata Research Articles

Mediterranean fruit fly population phenological patterns are strongly affected by elevation and host presence

The Mediterranean fruit fly (medfly) (Ceratitis capitata, Diptera: Tephritidae), is an extremely polyphagous pest that threatens the fruit production and trading industry worldwide. Monitoring C. capitata populations and analysing its dynamics and phenology is considered of outmost importance for designing and implementing sound management approaches. The aim of this study was to investigate the factors regulating the population dynamics of the C. capitata in a coastal and semi-mountainous area. We focused on effects of topography (e.g. elevation), host presence and seasonal patterns of ripening on the phenological patterns considering data collected in 2008. The experimental area is characterized by mixed fruit orchards, and Mediterranean climate with mild winters. Two trap types were used for population monitoring. The female targeted McPhail type and the male targeted Jackson type. Traps were placed in farms located at different elevations and landscape morphology (coastal and semi-mountainous areas). The main crops included citrus, apples, peaches, plums, pears, figs, quinces and apricots. Adult captures were first recorded in May, peaked in mid-summer and mid-autumn and almost ceased at the end of the season (January 2008). Captures in the coastal areas preceded that of highlands by 15 days. Most of the adults detected during the fruit ripening of late stone fruit cultivars (first peak) and citrus (second peak). The probability of capturing the first adults preceded almost three weeks the peak of adult captures either considering the elevation or host focus analyses. The results provide valuable information on the seasonal population trend of C. capitata in mixed fruit Mediterranean orchards and can support the set-up of IPM systems in areas with various landscapes and different hosts throughout the fruit growing season.

Evidence that recent climatic changes have expanded the potential geographical range of the Mediterranean fruit fly

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

Gene drive and genetic sex conversion in the global agricultural pest Ceratitis capitata

Homing-based gene drives are recently proposed interventions promising the area-wide, species-specific genetic control of harmful insect populations. Here we characterise a first set of gene drives in a tephritid agricultural pest species, the Mediterranean fruit fly Ceratitis capitata (medfly). Our results show that the medfly is highly amenable to homing-based gene drive strategies. By targeting the medfly transformer gene, we also demonstrate how CRISPR-Cas9 gene drive can be coupled to sex conversion, whereby genetic females are transformed into fertile and harmless XX males. Given this unique malleability of sex determination, we modelled gene drive interventions that couple sex conversion and female sterility and found that such approaches could be effective and tolerant of resistant allele selection in the target population. Our results open the door for developing gene drive strains for the population suppression of the medfly and related tephritid pests by co-targeting female reproduction and shifting the reproductive sex ratio towards males. They demonstrate the untapped potential for gene drives to tackle agricultural pests in an environmentally friendly and economical way.

RNAi-mediated silencing of Mediterranean fruit fly (Ceratitis capitata) endogenous genes using orally-supplied double-stranded RNAs produced in Escherichia coli.

The Mediterranean fruit fly (medfly), Ceratitis capitata Wiedemann, is a major pest affecting fruit and vegetable production worldwide, whose control is mainly based on insecticides. Double-stranded RNA (dsRNA) able to down-regulate endogenous genes, thus affecting essential vital functions via RNA interference (RNAi) in pests and pathogens, is envisioned as a more specific and environmentally-friendly alternative to traditional insecticides. However, this strategy has not been explored in medfly yet. Here, we screened seven candidate target genes by injecting in adult medflies gene-specific dsRNA hairpins transcribed in vitro. Several genes were significantly down-regulated, resulting in increased insect mortality compared to flies treated with a control dsRNA targeting the green fluorescent protein (GFP) complementary DNA (cDNA). Three of the dsRNAs, homologous to the beta subunit of adenosine triphosphate (ATP) synthase (ATPsynbeta), a vacuolar ATPase (V-ATPase), and the ribosomal protein S13 (RPS13), were able to halve the probability of survival in only 48 h after injection. We then produced new versions of these three dsRNAs and that of the GFP control as circular molecules in Escherichia coli using a two-self-splicing-intron-based expression system and tested them as orally-delivered insecticidal compounds against medfly adults. We observed a significant down-regulation of V-ATPase and RPS13 messenger RNAs (mRNAs) (approximately 30% and 90%, respectively) compared with the control medflies after 3 days of treatment. No significant mortality was recorded in medflies, but egg laying and hatching reduction was achieved by silencing V-ATPase and RPS13. In sum, we report the potential of dsRNA molecules as oral insecticide in medfly. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Smart insect monitoring based on YOLOV5 case study: Mediterranean fruit fly Ceratitis capitata and Peach fruit fly Bactrocera zonata

The agricultural sector in Egypt is adversely affected by factors such as inadequate soil fertility and environmental hazards such as pestilence and diseases. The implementation of early pest prediction techniques has the potential to enhance agricultural yield. Bactrocera zonata and Ceratitis capitata, known as peach fruit fly and Mediterranean fruit fly, respectively, are the predominant pests that cause significant damage to fruits on a global scale. The present study proposes a deep learning-based approach for the detection and quantification of pests. The proposed approach entails the retrieval of data pertaining to the adhesive trap condition, followed by its examination and presentation through a mobile application. The YOLOV5 model has been implemented for the purpose of pest classification, localization, and quantification. In order to address the issue of a restricted dataset, a hybrid technique of transfer learning and data augmentation (copy and paste) was employed. The proposed approach offers an intelligent real time pest detection, thereby facilitating the prediction of treatment options. An application for smartphones has been developed to aid farmers and agricultural professionals in the management and treatment of pests. The proposed approach has the potential to aid farmers in identifying the existence of pests, thereby diminishing the duration and resources needed for farm inspection. As per the results of the conducted experiments, the proposed approach demonstrates a noteworthy increase in performance. The weighted average accuracy reaches 84%, while precision (P), mean average precision (mAP), and F1-score show enhancements of up to 15%, 18%, and 7% respectively.

Prioritisation of quarantine pest list for the Caribbean using a multi-criteria decision approach

Quarantine plant pests are socially, economically and environmentally important due to their impact on food security, human health, global trade and crop production costs. The increase in global trade and tourism, frequent occurrence of natural disasters and climate changes have exacerbated the rate of entry, establishment and spread of plant pests regionally and globally. It has, therefore, become exigent to develop a list of pests of quarantine importance at the regional and national levels to prioritise and allocate the limited available resources to manage the associated risks. In the present study, the Technical Committee on the Formulation and Prioritisation of a Regional Priority Pest List for the Caribbean, in collaboration with the National Plant Protection Organisation of the Caribbean countries and the United States Department of Agriculture - Animal and Plant Health Inspection Service (USDA-APHIS), developed and prioritised a quarantine pest list using a multi-criteria decision-making approach. The technical committee successfully evolved the process in 2014 and 2018 and developed a list of the top 10 pests of quarantine importance for the Caribbean Region, employing the Delphi Technique (DT) and Analytical Hierarchy Process (AHP) through the assignment of criteria that are relevant to the region. The Mediterranean fruit fly (Ceratitis capitata), frosty pod rot (Moniliophthora roreri) and the tomato leaf miner (Tuta absoluta), listed as top quarantine pest threats, were subsequently detected in the region. This exercise guided the authorities in advance to allocate resources and to develop response plans including capacity building for surveillance and detection of priority pests. This has demonstrated the significance and appropriateness of the multi-criteria decision approach to determine priority pest lists and prepare the region for development of better management practices.

Female Sex Determination Factors in Ceratitis capitata: Molecular and Structural Basis of TRA and TRA2 Recognition.

In the model system for genetics, Drosophila melanogaster, sexual differentiation and male courtship behavior are controlled by sex-specific splicing of doublesex (dsx) and fruitless (fru). In vitro and in vivo studies showed that female-specific Transformer (TRA) and the non-sex-specific Transformer 2 (TRA2) splicing factors interact, forming a complex promoting dsx and fru female-specific splicing. TRA/TRA2 complex binds to 13 nt long sequence repeats in their pre-mRNAs. In the Mediterranean fruitfly Ceratitis capitata (Medfly), a major agricultural pest, which shares with Drosophila a ~120 million years old ancestor, Cctra and Cctra2 genes seem to promote female-specific splicing of Ccdsx and Ccfru, which contain conserved TRA/TRA2 binding repeats. Unlike Drosophila tra, Cctra autoregulates its female-specific splicing through these putative regulatory repeats. Here, a yeast two-hybrid assay shows that CcTRA interacts with CcTRA2, despite its high amino acid divergence compared to Drosophila TRA. Interestingly, CcTRA2 interacts with itself, as also observed for Drosophila TRA2. We also generated a three-dimensional model of the complex formed by CcTRA and CcTRA2 using predictive approaches based on Artificial Intelligence. This structure also identified an evolutionary and highly conserved putative TRA2 recognition motif in the TRA sequence. The Y2H approach, combined with powerful predictive tools of three-dimensional protein structures, could use helpful also in this and other insect species to understand the potential links between different upstream proteins acting as primary sex-determining signals and the conserved TRA and TRA2 transducers.

Microbial Biotransformation of Male Specific Pheromone α-Copaene with Cunninghamella elegans and Antibacterial Activity of Its Transformed Products

Pharmaceutical industries are increasingly turning to microbial transformation instead of chemical methods. This is because microbial biotransformation is a more effective way to produce pharmacologically active molecules with high specificity and efficient yield. Additionally, it is a step towards eco-friendly synthesis. α-Copaene (1), a tricyclic sesquiterpene, is a potent attractant of the male Mediterranean fruit fly Ceratitis capitata. This paper presents the utilization of the filamentous fungus Cunninghamella elegans TSY 0865 for large-scale biotransformation of 1. α-Copaene (1) has been incubated with Cunninghamella elegans for 11 days and extracted with CH2Cl2. Four new hydroxylated metabolites 10,13-dihydroxycopaene (2); 11,13-dihydroxycopaene (3); 11-hydroxycopaen-5-one (4); and 11-hydroxy-13-copaenic acid (5) were afforded. The structures of the new metabolites were elucidated by 1D (1H, 13C) and 2D NMR (COSY, HMBC, HMQC, and NOESY) techniques and MS analyses. Metabolite 5 exhibited significant antibacterial activity against Bacillus subtilis and Pseudomonas aeruginosa.

Iğdır İli Meyve Bahçelerinde Ceratitis capitata (Wiedemann, 1824) (Diptera: Tephritida)’nın Popülasyon Gelişimi, Yoğunluğu ve Bulaşıklık Oranının Belirlenmesi

Bu çalışma, Akdeniz meyvesineği (Ceratitis capitata (Wiedemann, 1824) (Diptera: Tephritidae))’nin ergin popülasyon gelişimi ve kültür bitkilerindeki zarar oranını belirlemek amacıyla 2021 yılında Iğdır ili Merkez ilçeye bağlı köylerde elma, armut, şeftali ve nektarin bahçelerinde yürütülmüştür. Zararlının popülasyonu bölgeyi temsilen Bayraktutan, Çalpala, Kuzugüden ve Küllük köylerinde birer meyve bahçesinde feromon ihtiva eden delta tuzak + McPhail tipi tuzaklar kullanılarak takip edilmiştir. Bahçelere yerleştirilen tuzaklar yerden 1.5 – 2.0 m yükseklikte ağaçların dışa bakan dallarının güney ve güney doğu yönüne yerleştirilmiştir. Tuzaklarda yakalanan erginlerin sayımı 5 Eylül 2021 ile 21 Kasım 2021 tarihleri arasında haftada bir kez yapılmıştır. Meyvelerdeki zarar oranı erginlerin tuzaklarda görülmeye başladığı tarihten itibaren iki haftada bir bahçelerden rastgele seçilen 50 armut, elma, şeftali veya nektarin meyveleri incelenerek belirlenmiştir. Akdeniz meyve sineği ergin popülasyonunun en yüksek seviyesi 24 Ekim 2021 tarihinde kayıt edilmiştir. İlk erginler 5 Eylül tarihinde görülmüştür. Zararlı popülasyonu 24 Ekim tarihinde tuzak başına en fazla yoğunluğa 200 ergin/hafta ile ulaşırken, 14 Kasım tarihinde 73 ergin/hafta ile ikinci en yüksek popülasyon yoğunluğuna ulaşıldığı tespit edilmiştir. Meyve bahçelerine göre en yüksek hasar oranı olan meyve türü, Bayraktutan lokasyonunda nektarin %17.6, Çalpala lokasyonunda şeftali %12, Kuzuguden lokasyonunda %8.4, Küllük lokasyonunda şeftali %18.4 olarak belirlenmiştir.

Nanoformulations with exopolysaccharides from cyanobacteria: enhancing the efficacy of bioactive molecules in the Mediterranean fruit fly control

The increasing demand for food has required intensive use of pesticides which are hazardous to the ecosystem. A valid alternative is represented by biopesticides; however, these molecules are often insoluble in water, and poorly bioavailable. Nanopesticides can be engineered to reach a selected target with controlled release of the active principle. In this work, capsaicin, an irritant alkaloid from hot chili peppers, and hydroxytyrosol, a phenolic compound obtained from extra-virgin olive oil by-products, were loaded into innovative nanocarriers. These were designed ad hoc combining exopolysaccharides from the cyanobacteria Neocyanospira capsulata, and a lipid component, i.e., egg phosphatidylcholine. The polysaccharide was chosen for chemical affinity with the chitin of insect exoskeleton, while the lipids were introduced to modulate the carrier rigidity. The newly formed nanosystems were characterized by physico-chemical techniques and tested for their possible use in pest control programs. The Mediterranean Fruit Fly Ceratitis capitata Wiedemann, 1824 (Diptera, Tephriditae), a pest of the Mediterranean Region causing high economic losses, was used as a model insect. We found that the nanoformulations nanocarriers prepared in this work, were able to increase the ovicidal effect of hydroxytyrosol. Moreover, the formulation encapsulating either hydroxytyrosol or capsaicin were able to reduce the number of females landing on treated apricots.Graphical

Early and off-season biological control of medfly with entomopathogenic nematodes: From laboratory experiments to successful field trials

The Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) is an important pest of citrus and other deciduous fruit trees. There is a need for sustainable pest management tools and the use of entomopathogenic nematodes have been explored for controlling the stages of medfly that occur in the soil. We have investigated further this approach by assessing the efficacy of commercially available entomopathogenic nematodes applied early season or off-season when the medfly populations are passing through their annual bottleneck period, aiming at reducing their population before the growing season. In laboratory experiments, the efficacy of commercial strains of Steinernema carpοcapsae, Steinernema feltiae, Heterοrhabditis bacteriοphοra and H. downesi at doses of 1.5 × 106 IJs/m2 and 2.5 × 106 IJs/m2, at 15C° and 25C° was assessed. Steinernema feltiae was found to result in up to 70 % reduction of adult medfly emergence at a dose of 2.5 × 106 IJs/m2 and lower temperatures, confirming its superiority over other commercially available species. Field trials in citrus groves in Corinthos, Greece in Spring 2021 (early season) and Autumn 2021 (off-season) showed that a single application of S. feltiae at moderate dose regimes can provide about 62–65 % suppression of adult medlfies. Therefore, a single, moderate dose application of entomopathogenic nematodes early or off-season, which is more economically feasible can provide significant suppression of overwintering medflies and can be safely integrated with other tools for medfly management.

Efficiency of some Weather Factors on the Activity of Mediterranean Fruit Fly Ceratitis Capitata (Wiedemann) (Diptera: Tephritidae) on Guava Orchards at El-Dakhlia and Kafr El-Shaikh Governorate.

Efficiency of some Weather Factors on the Activity of Mediterranean Fruit Fly Ceratitis Capitata (Wiedemann) (Diptera: Tephritidae) on Guava Orchards at El-Dakhlia and Kafr El-Shaikh Governorate.

Effect of climate change on the spatio-temporal distribution of the Mediterranean fruit fly Ceratitis capitata Wiedemann (1824) in Algeria

This study was carried out in order to determine the initial distribution of Mediterranean fruit fly Ceratitis capitata Wiedemann (1824) (Diptera, Tephrididae) in Algeria, the area now occupied and assess the role of climate change in determining its current distribution. The various surveys and trapping of adults indicate that in addition to the coastal, sub-coastal and Argan regions, this fly is also present in oases. It is reported in all the traditional oases where fruit trees are intercropped with date palm. From the 2000s, the area occupied by this fruit fly increased and spread into provinces where it was not previously reported. Gradually, it increased in abundance and became an important pest. The climate data recorded in the province of Batna (Aurès Mountains, Saharan Atlas) indicate there has been a change in climate. The annual and monthly average temperatures and relative humidity for the period 2000–2018, in this province became more favourable for this fruit fly than in the period 1913–1937, in particular, during the months of March, April, October and November. The results also indicate that in orchards where there are several types of fruit, the numbers of this fly are higher than where mainly apples are grown.

Determination of the Physiological Age in Two Tephritid Fruit Fly Species Using Artificial Intelligence.

The Mexican fruit fly (Anastrepha ludens, Loew, Diptera: Tephritidae) and the Mediterranean fruit fly (Ceratitis capitata, Wiedemann, Diptera: Tephritidae) are among the world's most damaging pests affecting fruits and vegetables. The Sterile Insect Technique (SIT), which consists in the mass-production, irradiation, and release of insects in affected areas is currently used for their control. The appropriate time for irradiation, one to two days before adult emergence, is determined through the color of the eyes, which varies according to the physiological age of pupae. Age is checked visually, which is subjective and depends on the technician's skill. Here, image processing and Machine Learning techniques were implemented as a method to determine pupal development using eye color. First, Multi Template Matching (MTM) was used to correctly crop the eye section of pupae for 96.2% of images from A. ludens and 97.5% of images for C. capitata. Then, supervised Machine Learning algorithms were applied to the cropped images to classify the physiological age according to the color of the eyes. Algorithms based on Inception v1, correctly identified the physiological age of maturity at 2 d before emergence, with a 75.0% accuracy for A. ludens and 83.16% for C. capitata, respectively. Supervised Machine Learning algorithms based on Neural Networks could be used as support in determining the physiological age of pupae from images, thus reducing human error and uncertainty in decisions as when to irradiate. The development of a user interface and an automatization process could be further developed, based on the data obtained on this study.

Comparative efficacy of a spider knottin insecticide, GS‐omega/kappa‐Hxtx‐Hv1a, against four species of invasive tropical tephritids

AbstractInvasive tephritid fruit flies collectively pose a significant economic challenge to agricultural pest management globally. Insecticide resistance to a number of previously effective chemical classes has increased the risk these pests pose as management options become limited. We evaluated the efficacy of a peptide‐based biorational insecticide with a unique mode of action, containing the active ingredient, GS‐omega/kappa‐Hxtx‐Hv1a (GS‐Hv1a), against four of tephritid species, oriental fruit fly (Bactrocera dorsalis), melon fly (Zeugodacus cucurbitae), Mediterranean fruit fly (Ceratitis capitata, ‘Medfly’), and Malaysian fruit fly (Bactrocera latrifrons). This assessment aimed to determine whether GS‐Hv1a has the potential for effective management of tropical tephritids, particularly in regions where insecticide resistance has developed to other products. We conducted two sets of screening assays with different methods of exposure, oral and topical and compared survival over time in response to increasing concentrations of GS‐Hv1a up to 3.86 mg/ml. We found that efficacy was species dependent: Ceratitis capitata was susceptible following topical exposure, while the other species of fruit fly were not. While Medfly survival decreased following oral ingestion as well, the amount required to achieve this was greater than the concentration used in the topical bioassay. We observed that survival continued to decline up to 72 h after exposure, indicating a delayed effect similar to other reduced‐risk insecticidal products such as fipronil. For this reason, GS‐Hv1a may be useful as a horizontal transfer tool in conjunction with C. capitata male pheromone lures.

Effect of Wolbachia Infection and Adult Food on the Sexual Signaling of Males of the Mediterranean Fruit Fly Ceratitis capitata.

Simple SummaryThe Mediterranean fruit fly (medfly) can infest many plant species and survive in different climatic conditions, thus leading to its invasion in new geographical regions and causing great economic losses in fruit production. Insecticides have been the major approach for the suppression of medfly populations for decades. However, concerns regarding insecticide impact on the environment led to the development of environmentally friendly techniques that rely on field releases of sterile males that produce no viable offspring when mated with wild females. One method of male sterilization is their infection with bacteria such as Wolbachia that induce sterility in infected males when crossed with uninfected wild females. The released sterile males should be competitive with wild males for mating with wild females. Therefore, it is important to evaluate the effect of Wolbachia on traits that determine male mating success, such as sexual pheromone signaling, and assess potential ways to improve mating success (i.e., enrichment of male diet with protein). In this study, we demonstrate that Wolbachia infection decreases sexual signaling frequency, but protein-enriched diets cannot counteract this negative effect. Our results contribute to the assessment of Wolbachia infection as an additional tool for population suppression of insect pests.Sexual signaling is a fundamental component of sexual behavior of Ceratitis capitata that highly determines males’ mating success. Nutritional status and age are dominant factors known to affect males’ signaling performance and define the female decision to accept a male as a sexual partner. Wolbachia pipientis, a widespread endosymbiotic bacterium of insects and other arthropods, exerts several biological effects on its hosts. However, the effects of Wolbachia infection on the sexual behavior of medfly and the interaction between Wolbachia infection and adult food remain unexplored. This study was conducted to determine the effects of Wolbachia on sexual signaling of protein-fed and protein-deprived males. Our findings demonstrate that: (a) Wolbachia infection reduced male sexual signaling rates in both food regimes; (b) the negative effect of Wolbachia infection was more pronounced on protein-fed than protein-deprived males, and it was higher at younger ages, indicating that the bacterium regulates male sexual maturity; (c) Wolbachia infection alters the daily pattern of sexual signaling; and (d) protein deprivation bears significant descent on sexual signaling frequency of the uninfected males, whereas no difference was observed for the Wolbachia-infected males. The impact of our findings on the implementation of Incompatible Insect Technique (IIT) or the combined SIT/IIT towards controlling insect pests is discussed.

Evaluation of insecticidal activity of Lavandula coronopifolia essential oil against the Mediterranean fruit fly Ceratitis capitata Wiedemann (Diptera: Tephritidae)

The present investigation was aimed to assess the toxicity of Lavandula coronopifolia (Lamiaceae) essential oil (EO) against adult Mediterranean fruit fly. Ceratitis capitata (Wiedemann) (Diptera Tephritidae) is one of the most destructive fruit pests in Morocco.Essential oil was extracted from leaves of lavender (L. coronopifolia) by hydrodistillation and analyzed by GC and GC/MS. The main compound is carvacrol (48.9%) followed by E-caryophyllene (10.8%) and caryophyllene oxide (7.7%).The EO was examined in the laboratory for 7 days to assess their activity against Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) adults by ingestion toxicity. We also conducted oviposition bioassay in the laboratory, testing the oviposition deterrence of essential oils.The oil showed 75% mortality of adults at the concentration of 150 µl/g after 24 h of exposure. Great differences in insect mortality were observed depending on the sex of the insects, oil concentrations and exposure time.The ingestion toxicity potential of L. coronopifolia on adults was higher (LC 50 = 86.34 µl/g, LC 95 = 236.07 µl/g) and also, deterred significantly the oviposition by C. capitata, reducing the number of eggs laid by about 94% compared with the controls for the concentration of 55µl/g.Results suggested that L. coronopifolia EOs may have potential as a control agent against this major stored product insect.

Determination of Quality Parameters and Sensory Attributes of ‘Jaffa’ Oranges Irradiated as Postharvest Quarantine Treatment Throughout Long-Term Cold Storage

The Mediterranean fruit fly (Ceratitis capitata) is one of the major problems in the citrus producing and trading countries including Turkey. Commercial application of radiation processing can be the alternative and effective solution to overcome this problem. The objective of the present study was the determination the sensory attributes, quality parameters and also cold storage shelf-life of ‘Jaffa’ oranges (Citrus sinensis (L) Osbeck) irradiated (0, 0.5, 1.0 and 1.5 kGy) as considering postharvest quarantine treatment for the Mediterranean fruit fly (Ceratitis capitata). The quality parameters of the control and irradiated oranges were determined in terms of weight loss, pH, titratable acidity, total soluble solids, reducing sugars, vitamin C content, total carotenoids, pectin, color of fruit during cold storage at 4 ± 0.1 oC and 85 - 90 % relative humidity (RH) on the 0, 15, 30 and 45 d of storage. Obtained results showed that, low dose irradiation is applicable regarding as other significant quality parameters of ‘Jaffa’ oranges such as vitamin C, total carotenoids, invert sugars, pectin, weight loss, pH, acidity and total soluble solids did not affect consumption and commercial value of ‘Jaffa’ sweet oranges up to 45 d of storage at 4 oC. According to overall sensory attributes, irradiated fruit were still acceptable as judged by panelists and ≤1.0 kGy irradiation dose more suitable for keeping important attributes of processed ‘Jaffa’ orange fruit.

Rearrangements in the musculature correlate with jumping behaviour in legless Mediterranean fruit fly larvae Ceratitis capitata (Tephritidae)

Larvae of holometabolic insects evolved different crawling strategies depending on the presence or absence of larval legs or life style. A rather unusual mode of locomotion has independently evolved in legless larvae of several dipteran species. Maggots of the Mediterranean fruit fly Ceratitis capitata developed an effective jumping mechanism to increase locomotion speed or to deter predators during the search for suitable pupation sites. Here, we use high-speed videography to visualize even the fastest movements during jump preparation and take-off. Quantification of kinetic and biometric parameters reveal that maggots jump up to 15-fold of their body length from a standing position and gain speed with 27 times the acceleration of gravity. Videos at high spatial resolution show the mechanism of latch formation and release in unprecedented detail. Mouth hooks insert in the caudal segment and raise a cuticular fold that serves as a handle to pressurize the body prior to launch. Since locomotion behaviour should be intrinsically linked to neuromuscular systems, we dissected third instar larvae and determined the precise pattern of abdominal muscles fibres. Compared to non-jumping dipteran larvae, such as Drosophila melanogaster, the overall arrangement is highly similar, but a few muscle fibres show characteristic re-arrangements in orientation and strength that are consistent with a role in bending and jumping. These results suggest that body wall muscles show adaptations to jumping behaviour in Ceratitis larvae, and possibly also in other species with different jumping techniques.

Identifying an Optimal Screen Mesh to Enable Augmentorium-Based Enhanced Biological Control of the Olive Fruit Fly Bactrocera oleae (Diptera: Tephritidae) and the Mediterranean Fruit Fly Ceratitis capitata (Diptera: Tephritidae).

The augmentorium is a cost-effective screened enclosure designed to receive fruits infested with insect pests, retain the pests inside but let their natural enemies escape to enhance biological control of pest populations. Screen selection is critical to ensure that an augmentorium is effective for a particular system. Here we tested five types of screens with a mini-augmentorium design and measured the escape of four insect species under laboratory conditions: the pests olive fruit fly Bactocera oleae (Rossi) (Diptera: Tephritidae) and Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), and the parasitoids Psyttalia lounsburyi (Silvestri) (Hymenoptera: Braconidae) and Psyttalia ponerophaga (Silvestri) (Hymenoptera: Braconidae). The sex ratio of insects that escaped the screens was compared to the sex ratio of insects that could not escape. Results showed that one screen type ('crystal mesh') was the best for the purpose of designing a functional augmentorium: it retained 90% of B. oleae adults and 100% of C. capitata adults while letting 72% of Psyttalia lounsburyi adults and 94% of P. ponerophaga adults escape. The other screen types tested were suboptimal, either because they let too many flies freely escape or because they retained too many parasitoids. Sex ratio was almost always similar for insects that managed to escape the screens and insects that were retained, except for P. ponerophaga and the screen type 'light mesh'. These results are promising for the development of a functional augmentorium against the olive fruit fly and further implementation against Mediterranean fruit fly.