Fruit Fly Larvae Research Articles

Drosophila larval glue sticks to anything

Sticking to a surface is all part of the rite of passage from larva to adult for fruit flies (Drosophila melanogaster). After spitting out their sticky secretions, the larvae wriggle around to ensure that their salivary adhesive is smeared evenly between their body and the surface before it cures to form a secure bond. ‘The glue is composed of a small number of proteins called salivary gland secreted proteins’, says Virgine Courtier-Orgogozo, from the Institut Jacques Monod, France, who wants to identify the genes involved in glue adhesion to understand how the adhesive has evolved. However, before she could begin unravelling the details, Courtier-Orgogozo and her PhD student Flora Borne teamed up with insect attachment experts Alexander Kovalev and Stanislav Gorb from the University of Kiel, Germany, to find out how well the adhesive attaches to different surfaces.Using glass slides, which water spreads across with ease, slides treated to make them water-repellent and electrically chargeable epoxy resin surfaces, the team allowed 328 fruit fly larvae to settle on the different surfaces and secure themselves in preparation for pupation. Then, the scientists attached a force transducer to each pupa, before tugging on them to find out how tightly they had adhered, with only 56 detaching cleanly as the glue gave way. Calculating the force required to tear the pupae free, Courtier-Orgogozo was amazed that the adhesive could hold on with a force of ∼217 mN, 15,500 times the weight of a pupa. But she was most intrigued that the adhesive took hold successfully on all of the different surfaces, regardless of how water-repellent or chargeable they were.‘Amazing! How lucky to have such a universal glue at hand!’ exclaimed Courtier-Orgogozo, who is now eager to find out how well the adhesive adheres to more natural surfaces. And she is also keen to find out if she can learn how the adhesive gained its strength. ‘Our study paves the way for a genetic dissection of the components of D. melanogaster glue that confer its particular adhesive properties’, she says.

Recruitment of an insect and its nematode natural enemy by olfactory cues from a saprophytic fungus

Olfactory signals are critical for soil inhabitants to communicate and respond to the environment. In addition to the well-documented volatile cues from herbivores and herbivory-induced plants, attraction of both entomopathogenic nematodes (EPNs) and insect prey was recently shown to be induced by a saprophytic fungus Fusarium solani. Here, we used headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS), to identify two volatile organic compounds (VOCs), 1-pentanol and 1-octen-3-ol (octenol), from F. solani. In olfactometer bioassays, the infective juvenile stage of the EPN Steinernema diaprepesi was attracted to both VOCs. Although octenol was highly attractive to fungivorous Drosophila melanogaster fruit fly larvae, the non-fungivorous Diaprepes abbreviatus root weevil larvae were repelled by the compound. In soil microcosms, the VOCs delayed the infection of root weevil larvae by S. diaprepesi but facilitated S. diaprepesi infection of fly larvae. Presumably octenol attracted the flies and EPNs to a common locale, while provoking greater separation of EPNs and root weevils than occurred in the absence of the chemical. EPNs may have evolved to exploit these VOCs as a means of encountering fungivorous insects, whereas non-fungivorous arthropods may have evolved to avoid the compounds.

Multiple Requirements for Rab GTPases in the Development of Drosophila Tracheal Dorsal Branches and Terminal Cells.

The tracheal epithelium in fruit fly larvae is a popular model for multi- and unicellular migration and morphogenesis. Like all epithelial cells, tracheal cells use Rab GTPases to organize their internal membrane transport, resulting in the specific localization or secretion of proteins on the apical or basal membrane compartments. Some contributions of Rabs to junctional remodelling and governance of tracheal lumen contents are known, but it is reasonable to assume that they play important further roles in morphogenesis. This pertains in particular to terminal tracheal cells, specialized branch-forming cells that drastically reshape both their apical and basal membrane during the larval stages. We performed a loss-of-function screen in the tracheal system, knocking down endogenously tagged alleles of 26 Rabs by targeting the tag via RNAi. This revealed that at least 14 Rabs are required to ensure proper cell fate specification and migration of the dorsal branches, as well as their epithelial fusion with the contralateral dorsal branch. The screen implicated four Rabs in the subcellular morphogenesis of terminal cells themselves. Further tests suggested residual gene function after knockdown, leading us to discuss the limitations of this approach. We conclude that more Rabs than identified here may be important for tracheal morphogenesis, and that the tracheal system offers great opportunities for studying several Rabs that have barely been characterized so far.

Diversity of Bactrocera spp. on some mango varieties at Kecamatan Talun, Kabupaten Cirebon

Fruit fly (Bactrocera spp.) is a major pest of horticultural crops, especially fruits. Fruit fly larvae feed on the flesh of fruit, and cause the decrease of both quantity and quality of the production. Fruit fly species on certain fruit in an area is important to be identified to make a right decision in choosing the control methods. The objectives of this study were to identify the fruit fly species, and determine the dominant species and diversity index of fruit flies on mangoes Gedong Gincu, Cengkir, and Arumanis at Kecamatan Talun, Kabupaten Cirebon, Indonesia. The survey was carried out by collecting samples of mango fruit attacked by fruit flies from field, wholesaler, and retailer at Kecamatan Talun. The results showed that there were four species that attack mangoes Gedong Gincu, Cengkir, and Arumanis at Kecamatan Talun, namely B. dorsalis; B. carambolae; interspesific hybrids of B. carambolae and B. dorsalis; and B. albistrigata. The dominant species was B. dorsalis. Diversity index (H’) of fruit fly species was 0,05 ≤ H’ ≤ 0,48 (H’ < 1,5), so that the diversity was considered low.

Occurrence, Identification, and Virulence of Native Fungal Pathogens Isolated From Mexican Fruit Fly (Diptera: Tephritidae) Larvae From Soils of Three Cropping Systems.

The Mexican fruit fly, Anastrepha ludens Loew, is a significant pest in mango and citrus production areas of Mexico. In this study, we evaluated the effects of some geographic characteristics, rainfall period, soil micro-environmental, and soil coverage variables on the occurrence of entomopathogenic fungi (EPF) associated with A. ludens larvae in soils of mango, grapefruit and mixed crops in central Veracruz state, Mexico. EPF isolates were characterized morphologically and identified by sequence analysis of elongation factor (EF1-1018F, EF1-1620R). We recorded four species of EPF (Metarhizium robertsii J.F. Bisch, S.A. Rehner & Humber [Hypocreales: Cordycipitaceae], M. brunneum Petch [Hypocreales: Cordycipitaceae], M. pinghaense Q.T. Chen & H.L. Guo [Hypocreales: Cordycipitaceae], and Beauveria bassiana (Balsamo) Vuillemin [Hypocreales: Cordycipitaceae]), of which Metarhizium robertsii was the most abundant and the most virulent. Also, we found that rainfall period, organic matter, coverage of herbs and forbs, and calcium levels modulated EPF occurrence. We estimated lethal concentrations for A. ludens larvae of the four most promising isolates, V3-123, V3-160, V1-332, and V3-369. Our results suggest that M. robertsii obtained from agricultural soils holds potential as a biological control agent for A. ludens.

Gamma Irradiation Treatment of Bactrocera dorsalis Hendel (Diptera: Tephritidae) in Snake Fruit

Snake fruit (Salacca zalacca) is a unique fruit and it has decadent prospects to be developed as an export commodity. Nevertheless, oriental fruit fly, Bactrocera dorsalis Hendel seems to decrease the quantity and quality of this fruit. On the other side, irradiation has been developed as a standard quarantine treatment to disinfest fruit fly on fruit. The objective of this research was to determine impact of irradiation by Cobalt-60 gamma-ray on the development and survivorship of eggs and the third instar of fruitfly larvae using in-vitro and in-vivo approaches and minimum dose of Cobalt-60 gamma rays applied for snake fruit. Six doses of gamma-ray, i.e. 0 (control), 25, 50, 75, 100, 125 and 150 Gy were used in this experiment. The results showed that Cobalt-60 disturbed development and survivor rate of B. dorsalis. The development of eggs into pupa was failed when treated with Cobalt-60 at any doses, while the third instar larvae failed to become adult when irradiated with 75, 100 and 150 Gy of gamma-ray. The impacts were increased with the increment of dose. Furthermore, impact of gamma-ray irradiation was greater on eggs compared to the third instar of larvae. The minimum dose of irradiation to prevent adults emerge was 118 Gy.

Diversity of Fruit Flies (Diptera: Tephritoidea) and Their Host Plants in a Conservation Unit from Midwestern Brazil

Fruit flies (Diptera: Tephritidae and Lonchaeidae) are among the principal phytophagous insects of fruit and vegetables. Their larvae feed on the pulp or seeds of fruits to complete their development, which favors the entry of pathogens and early fall of the fruits, damaging fruit production. The objectives of this research were to determine the richness of fruit fly species and their associations with their host fruits in the Serra da Bodoquena National Park (Mato Grosso do Sul State, Brazil) and surrounding areas. To obtain the fruit fly species from their hosts, monthly collections of fruits were made. Leaf samples were prepared and identified by botanists. The collected fruits were transported to the Laboratorio de Insetos Frugivoros, where they were counted and weighed. The species of fruit flies were identified, and their trophic interactions with their hosts analyzed. Thirty-nine plant species from 29 plant families were collected. Twelve fruit species were hosts to fruit fly larvae. The survey resulted in the recovery of 1,476 larvae and 968 adult fruit flies. Among the adults, 878 were Tephritidae and 90 Lonchaidae. Nine species from the genus Anastrepha (Diptera: Tephritidae) and 3 from Neosilba (Diptera: Lonchaeidae) were obtained. These are the first reports for Anastrepha serpentina (Wiedemann), Anastrepha fraterculus (Wiedemann), and Anastrepha obliqua (Macquart) (all Diptera: Tephritidae) infesting fruits of Eugenia myrcianthes Nied (Myrtaceae); Anastrepha striata Schiner (Diptera: Tephritidae) infesting Jacaratia spinosa Aubl. (Caricaceae); Anastrepha zenildae Zucchi (Diptera: Tephritidae) infesting Campomanesia guazumifolia (Cambess) O. Berg. (Myrtaceae); Neosilba glaberrima (Wiedemann) and Neosilba zadolicha McAlpine & Steyskal are recorded for the first time infesting Persea americana Miller (Lauraceae), and Neosilba certa (Walker) (all Diptera: Lonchaeidae) infesting Chrysophyllum gonocarpum (Mart. & Eichler) Engl. (Sapotaceae), Anastrepha barbiellinii Lima (Diptera: Tephritidae) is recorded for the first time infesting Pereskia aculeata Miller (Cactaceae) in Mato Grosso do Sul State.

Purification of a trypsin inhibitor from Psoralea corylifolia seeds and its influence on developmental physiology of Bactrocera cucurbitae

A trypsin inhibitor was purified from the seeds of Psoralea corylifolia by ion-exchange and affinity chromatography. The purified fractions were subjected to RP- HPLC which resolved into a single peak. SDS-PAGE analysis gave an apparent molecular weight of 18 kDa. P. corylifolia trypsin inhibitor (PCTI) was found to be a competitive inhibitor and was active over a broad temperature (10–100 °C) and pH (6–11) range. It was shown to have a deleterious effect on growth and development of larvae of the melon fruit fly, Bactrocera cucurbitae, when incorporated in artificial diet using various concentrations. The larval, pupal, total development period and larval mortality significantly increased during the treatment. Inhibitory effects were also observed on percentage emergence which was significantly reduced. Nutritional indices namely food assimilated (FA) and mean relative growth rate (MRGR) also decreased significantly with increase in concentration of PCTI. qRT-PCR results indicated that the expression of trypsin and chymotrypsin genes were down-regulated while elastase, catalase, GST, SOD and AP were up-regulated. PCTI was also effective against certain bacterial strains. These results indicated that the peptidase inhibitor from P. corylifolia may be a potential bio-control agent which can decrease the damage caused by B. cucurbitae and other related destructive pests.

A Single MicroRNA-Hox Gene Module Controls Equivalent Movements in Biomechanically Distinct Forms of Drosophila

SummaryMovement is the main output of the nervous system. It emerges during development to become a highly coordinated physiological process essential to survival and adaptation of the organism to the environment. Similar movements can be observed in morphologically distinct developmental stages of an organism, but it is currently unclear whether or not these movements have a common molecular cellular basis. Here we explore this problem in Drosophila, focusing on the roles played by the microRNA (miRNA) locus miR-iab4/8, which we previously showed to be essential for the normal corrective response displayed by the fruit fly larva when turned upside down (self-righting). Our study shows that miR-iab4 is required for normal self-righting across all three Drosophila larval stages. Unexpectedly, we also discover that this miRNA is essential for normal self-righting behavior in the adult fly, an organism with different morphology, neural constitution, and biomechanics. Through the combination of gene expression, optical imaging, and quantitative behavioral approaches, we provide evidence that miR-iab4 exerts its effects on adult self-righting behavior in part through repression of the Hox gene Ultrabithorax (Ubx) in a specific set of adult motor neurons, the NB2-3/lin15 neurons. Our results show that miRNA controls the function, rather than the morphology, of these neurons and demonstrate that post-developmental changes in Hox gene expression can modulate behavior in the adult. Our work reveals that a common miRNA-Hox genetic module can be re-deployed in different neurons to control functionally equivalent movements in biomechanically distinct organisms and describes a novel post-developmental role of the Hox genes in adult neural function.

Foraging decisions as multi-armed bandit problems: Applying reinforcement learning algorithms to foraging data

Finding resources is crucial for animals to survive and reproduce, but the understanding of the decision-making underlying foraging decisions to explore new resources and exploit old resources remains lacking. Theory predicts an ‘exploration-exploitation trade-off’ where animals must balance their effort into either stay and exploit a seemingly good resource or move and explore the environment. To date, however, it has been challenging to generate flexible yet tractable statistical models that can capture this trade-off, and our understanding of foraging decisions is limited. Here, I suggest that foraging decisions can be seen as multi-armed bandit problems, and apply deterministic (i.e., the Upper-Confidence-Bound or ‘UCB’) and Bayesian algorithms (i.e., Thompson Sampling or ‘TS’) to demonstrate how these algorithms generate testable a priori predictions from simulated data. Next, I use UCB and TS to analyse empirical foraging data from the tephritid fruit fly larvae Bactrocera tryoni to provide a qualitative and quantitative framework to quantify animal foraging behaviour. Qualitative analysis revealed that TS display shorter exploration period than UCB, although both converged to similar qualitative results. Quantitative analysis demonstrated that, overall, UCB is more accurate in predicting the observed foraging patterns compared with TS, even though both algorithms failed to quantitatively estimate the empirical foraging patterns in high-density groups (i.e., groups with 50 larvae and, more strikingly, groups with 100 larvae), likely due to the influence of intraspecific competition on animal behaviour. The framework proposed here demonstrates how reinforcement learning algorithms can be used to model animal foraging decisions.

Is it possible to reconstruct an accurate cell lineage using CRISPR recorders?

This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).

Native parasitoids (Hymenoptera: Braconidae) of fruit flies (Diptera: Tephritidae) in Serra da Bodoquena National Park-MS, Brazil

Abstract: Fruit flies are among the main groups of phytophagous insects. Their larvae, when feeding on the pulp or seeds of the host fruits, can cause rot and favor the entrance of pathogens. Thus, the objectives of this study was: (1) To know the trophic associations between species of parasitoids and fruit flies in the Parque Nacional da Serra da Bodoquena (PNSB)-MS, Brazil. (2) To inventory the parasitoid species associated with fruit flies in fruit trees in the Parque Nacional da Serra da Bodoquena. Monthly expeditions were carried out (From Jan 2017 to Feb 2018) in order to collect the fruits and obtain the fruit flies (Tephritidae) and their respective parasitoids. The collected fruits were transported to the laboratory of frugivorous insects (LIF) of the Universidade Federal da Grande Dourados (UFGD)-MS. The fruit fly larvae were daily collected and placed in transparent acrylic cups containing sterilized sand, where they remained till the emergence of adults and their parasitoids. Twenty-Three adult Tephritid parasitoids were recovered, represented by two species of Braconidae: Doryctobracon areolatus (18) and Utetes anastrephae (5), both infesting Anastrepha species: Anastrepha fraterculus, A. sororcula and A. striata in Myrtaceae: Psidium guajava and Eugenia myrcianthes. Doryctobracon areolatus and Utetes anastrephae are reported for the first time parasiting Anastrepha species in Eugenia myrcianthes.

Recording Neural Activity in Unrestrained Animals with Three-Dimensional Tracking Two-Photon Microscopy

SUMMARYOptical recordings of neural activity in behaving animals can reveal the neural correlates of decision making, but brain motion, which often accompanies behavior, compromises these measurements. Two-photon point-scanning microscopy is especially sensitive to motion artifacts, and two-photon recording of activity has required rigid coupling between the brain and microscope. We developed a two-photon tracking microscope with extremely low-latency (360 μs) feedback implemented in hardware. This microscope can maintain continuous focus on neurons moving with velocities of 3 mm/s and accelerations of 1 m/s2 both in-plane and axially. We recorded calcium dynamics of motor neurons and inter-neurons in unrestrained freely behaving fruit fly larvae, correlating neural activity with stimulus presentations and behavioral outputs, and we measured light-induced depolarization of a visual interneuron in a moving animal using a genetically encoded voltage indicator. Our technique can be extended to stabilize recordings in a variety of moving substrates.

Efficacy of entomopathogenic nematodes Steinernema kraussei to control the fruit fly larvae

Efficacy of entomopathogenic nematodes Steinernema kraussei to control the fruit fly larvae

Statistical modelling of navigational decisions based on intensity versus directionality in Drosophila larval phototaxis

Organisms use environmental cues for directed navigation. Understanding the basic logic behind navigational decisions critically depends on the complexity of the nervous system. Due to the comparably simple organization of the nervous system of the fruit fly larva, it stands as a powerful model to study decision-making processes that underlie directed navigation. We have quantitatively measured phototaxis in response to well-defined sensory inputs. Subsequently, we have formulated a statistical stochastic model based on biased Markov chains to characterize the behavioural basis of negative phototaxis. Our experiments show that larvae make navigational decisions depending on two independent physical variables: light intensity and its spatial gradient. Furthermore, our statistical model quantifies how larvae balance two potentially-contradictory factors: minimizing exposure to light intensity and at the same time maximizing their distance to the light source. We find that the response to the light field is manifestly non-linear, and saturates above an intensity threshold. The model has been validated against our experimental biological data yielding insight into the strategy that larvae use to achieve their goal with respect to the navigational cue of light, an important piece of information for future work to study the role of the different neuronal components in larval phototaxis.

Near full-length 16S rRNA gene next-generation sequencing revealed Asaia as a common midgut bacterium of wild and domesticated Queensland fruit fly larvae

BackgroundGut microbiota affects tephritid (Diptera: Tephritidae) fruit fly development, physiology, behavior, and thus the quality of flies mass-reared for the sterile insect technique (SIT), a target-specific, sustainable, environmentally benign form of pest management. The Queensland fruit fly, Bactrocera tryoni (Tephritidae), is a significant horticultural pest in Australia and can be managed with SIT. Little is known about the impacts that laboratory-adaptation (domestication) and mass-rearing have on the tephritid larval gut microbiome. Read lengths of previous fruit fly next-generation sequencing (NGS) studies have limited the resolution of microbiome studies, and the diversity within populations is often overlooked. In this study, we used a new near full-length (> 1300 nt) 16S rRNA gene amplicon NGS approach to characterize gut bacterial communities of individual B. tryoni larvae from two field populations (developing in peaches) and three domesticated populations (mass- or laboratory-reared on artificial diets).ResultsNear full-length 16S rRNA gene sequences were obtained for 56 B. tryoni larvae. OTU clustering at 99% similarity revealed that gut bacterial diversity was low and significantly lower in domesticated larvae. Bacteria commonly associated with fruit (Acetobacteraceae, Enterobacteriaceae, and Leuconostocaceae) were detected in wild larvae, but were largely absent from domesticated larvae. However, Asaia, an acetic acid bacterium not frequently detected within adult tephritid species, was detected in larvae of both wild and domesticated populations (55 out of 56 larval gut samples). Larvae from the same single peach shared a similar gut bacterial profile, whereas larvae from different peaches collected from the same tree had different gut bacterial profiles. Clustering of the Asaia near full-length sequences at 100% similarity showed that the wild flies from different locations had different Asaia strains.ConclusionsVariation in the gut bacterial communities of B. tryoni larvae depends on diet, domestication, and horizontal acquisition. Bacterial variation in wild larvae suggests that more than one bacterial species can perform the same functional role; however, Asaia could be an important gut bacterium in larvae and warrants further study. A greater understanding of the functions of the bacteria detected in larvae could lead to increased fly quality and performance as part of the SIT.

Effects of anoxia on survival and gene expression in Bactrocera dorsalis

The oriental fruit fly (Bactrocera dorsalis) larvae may commonly experience a hypoxia microenvironment and have evolved the ability to survive in the low oxygen condition with some physiological and biochemical mechanisms. However, little is known about the response of B. dorsalis to hypoxia or anoxia. In this study, the effect of anoxia on the survival of B. dorsalis was investigated. The results showed that the B. dorsalis larvae were quite tolerant to anoxia conditions and can tolerate up to 24 h of anoxia exposure without a significant reduction in survival, 100% mortality was reached after 84 h of anoxia exposure. The cDNA of hypoxia inducible factor (HIF) 1α and HIF-1β is 2912 and 3618 bp in length, encoding 766 and 648 amino acid residues, respectively. Both HIF-1α and HIF-1β contain conserved basic helix-loop-helix (bHLH) domain and Per-Arnt-Sim (PAS) domain. HIF-1α can be induced by hypoxia, whereas HIF-1β expression was not significantly changed with the oxygen concentration. Three major heat shock proteins (Hsps) expression increased significantly during anoxia and recovery and Hsp70 was the most responsive to anoxia. Four superoxide dismutase (SOD) genes expression were also up-regulated during anoxia exposure. These data suggest that B. dorsalis has a strategy to induce HIF-1α and HIF-1-responsive genes to survive in the low oxygen condition.

Structural and Molecular Properties of Insect Type II Motor Axon Terminals

A comparison between the axon terminals of octopaminergic efferent dorsal or ventral unpaired median neurons in either desert locusts (Schistocerca gregaria) or fruit flies (Drosophila melanogaster) across skeletal muscles reveals many similarities. In both species the octopaminergic axon forms beaded fibers where the boutons or varicosities form type II terminals in contrast to the neuromuscular junction (NMJ) or type I terminals. These type II terminals are immunopositive for both tyramine and octopamine and, in contrast to the type I terminals, which possess clear synaptic vesicles, only contain dense core vesicles. These dense core vesicles contain octopamine as shown by immunogold methods. With respect to the cytomatrix and active zone peptides the type II terminals exhibit active zone-like accumulations of the scaffold protein Bruchpilot (BRP) only sparsely in contrast to the many accumulations of BRP identifying active zones of NMJ type I terminals. In the fruit fly larva marked dynamic changes of octopaminergic fibers have been reported after short starvation which not only affects the formation of new branches (“synaptopods”) but also affects the type I terminals or NMJs via octopamine-signaling (Koon et al., 2011). Our starvation experiments of Drosophila-larvae revealed a time-dependency of the formation of additional branches. Whereas after 2 h of starvation we find a decrease in “synaptopods”, the increase is significant after 6 h of starvation. In addition, we provide evidence that the release of octopamine from dendritic and/or axonal type II terminals uses a similar synaptic machinery to glutamate release from type I terminals of excitatory motor neurons. Indeed, blocking this canonical synaptic release machinery via RNAi induced downregulation of BRP in neurons with type II terminals leads to flight performance deficits similar to those observed for octopamine mutants or flies lacking this class of neurons (Brembs et al., 2007).

Drosophila larvae fed palm fruit juice (PFJ) delay pupation via expression regulation of hormetic stress response genes linked to ageing and longevity

Palm fruit juice (PFJ) containing oil palm phenolics is obtained as a by-product from oil palm (Elaeis guineensis) fruit milling. It contains shikimic acid, soluble fibre and various phenolic acids including p-hydroxybenzoic acid and three caffeoylshikimic acid isomers. PFJ has also demonstrated beneficial health properties in various biological models. Increasing concentrations of PFJ and different PFJ fractions were used to assess growth dynamics and possible anti-ageing properties in fruit flies (Drosophila melanogaster) genotype w1118. Microarray gene expression analysis was performed on whole fruit fly larvae and their fat bodies, after the larvae were fed a control Standard Brandeis Diet (SBD) with or without PFJ. Transcripts from Affymetrix GeneChips were utilised to identify the possible mechanisms involved, with genes having fold changes > |1.30| and p < 0.05 considered differentially expressed. PFJ dose-dependently delayed larval growth and pupation, but not percent eclosion from pupae. Eclosed male fruit flies fed PFJ or its fractions during the larval stage tended to have 20–40% improved survival ratings over controls when allowed to age on the control diet (SBD). Microarray analysis of whole fruit fly larvae revealed that 127 genes were up-regulated, while 67 were down-regulated by PFJ. Functional analysis revealed transport and metabolic processes were up-regulated, while development and morphogenesis processes, including the nutrient-sensing Tor gene, were down-regulated by PFJ, whereas microarray analysis of larval fat bodies found 161 genes were up-regulated, while 84 genes were down-regulated. Genes involved in defence response and determination of adult lifespan, including those encoding various heat shock proteins and the antioxidant enzyme Sod2, were up-regulated, while cell cycle and growth genes were down-regulated. Thus, PFJ supplementation lengthened the growth stages in fruit fly larvae that was reflected in extended ageing of adult flies, suggesting that larval expression of hormetic stress response genes was linked to subsequent ageing and longevity.

Description of the Larvae of Anastrepha curitis, Anastrepha pickeli and Anastrepha pulchra (Diptera: Tephritidae)

We describe and illustrate for the first time the third-instar larvae of three Anastrepha species, Anastrepha pickeli Lima, Anastrepha pulchra Stone, and Anastrepha curitis Stone, and also the second instar of A. curitis. Structures such as the cephalopharyngeal skeleton and spiracles are described using optical and scanning electron microscopy. We describe characteristics of the ventral surface of the mandible for the first time for fruit fly larvae.