Pachycrepoideus Vindemmiae Research Articles

Annotated checklist and illustrated key to parasitoids (Hymenoptera: Diapriidae, Eulophidae and Pteromalidae) of fruit flies (Diptera, Tephritidae) in Brazil.

The hymenopteran parasitoids of pest species of Tephritidae in Brazil are best known by their most prominent species, members of Braconidae and Figitidae. Species in the less-studied families Diapriidae, Eulophidae and Pteromalidae, which are mostly pupal parasitoids, have been largely neglected and the literature on these groups is sparse and scattered. Therefore, their importance as natural enemies of fruit flies is likely underestimated. Here, we present a parasitoid-host-plant checklist of all diapriids, eulophids and pteromalids that parasitize fruit flies of economic importance in Brazil, namely Anastrepha species and Ceratitis capitata. A compilation of information of the seven species of these parasitoids occurring in Brazil-Coptera haywardi Loiácono and Trichopria anastrephae Lima (Diapriidae), Tetrastichus giffardianus Silvestri (Eulophidae), Pachycrepoideus vindemmiae (Rondani), Spalangia endius Walker, S. gemina Bouček and S. simplex Perkins (Pteromalidae)-including their taxonomic status, general biology, and potential as biocontrol agents, is presented. Additionally, we provide an illustrated key to species, aiming to highlight key morphological features and facilitate identification at species level, stimulating future research on these groups.

Host searching and host preference of resident pupal parasitoids of Drosophila suzukii in the invaded regions

In its invaded regions, Drosophila suzukii (Matsumura) is a novel host for the community of resident parasitoids of Drosophila. To attain a high parasitization rate on the novel host, the parasitoids have to locate it and accept it in the presence of other Drosophila hosts. We conducted a laboratory choice experiment and a semifield trial to investigate host searching and host preference of the three pupal parasitoid species Trichopria drosophilae (Perkins), Pachycrepoideus vindemmiae (Rondani) and Spalangia erythromera Förster. All three parasitoid species preferred D. suzukii over two common native hosts in the choice experiment. In field cages, most parasitoid offspring emerged from D. suzukii hosts. While P. vindemmiae mainly parasitized hosts in the foliage, most T. drosophilae offspring emerged from pupae presented on the ground. Both P. vindemmiae and T. drosophilae have the potential to find and parasitize D. suzukii in the field. If released early in the season, possible nontarget effects on native Drosophila should be minimal.

Landscape Vegetation Productivity Influences Population Dynamics of Key Pests in Small Avocado Farms in Kenya.

Avocado (Persea americana Mill.) production contributes to the economic growth of East Africa. However, poor fruit quality caused by infestations of tephritid fruit flies (Tephritidae) and the false codling moth, Thaumatotibia leucotreta (Meyrick), hampers access to lucrative export markets. Remote sensing and spatial analysis are increasingly applied to crop pest studies to develop sustainable and cost-effective control strategies. In this study, we assessed pest abundance in Muranga, Kenya, across three vegetation productivity classes, viz., low, medium and high, which were estimated using the normalised difference vegetation index at a landscape scale. Population densities of the oriental fruit fly, Bactrocera dorsalis (Hendel) and T. leucotreta in avocado farms were estimated through specific baited traps and fruit rearing. The population density of T. leucotreta varied across the vegetation productivity classes throughout the study period, although not significantly. Meanwhile, B. dorsalis showed a clear trend of decrease over time and was significantly lower in high vegetation productivity class compared to low and medium classes. Ceratitis cosyra (Walker) was the most abundant pest reared from fruit with few associated parasitoids, Pachycrepoideus vindemmiae (Rondani) and Toxeumorpha nigricola (Ferriere).

Peppermint essential oil inhibits Drosophila suzukii emergence but reduces Pachycrepoideus vindemmiae parasitism rates

Spotted Wing Drosophila (Drosophila suzukii; Matsumura) is an invasive fruit fly with the ability to oviposit in a broad range of agriculturally valuable fruits. Volatile organic compounds (VOCs) produced by botanical oils may reduce D. suzukii’s attraction to hosts and decrease survival, but it is unknown whether their efficacy varies across D. suzukii life stages or affects the survival and success of higher trophic levels. Through a series of laboratory bioassays, we evaluated the effects of peppermint (Mentha arvensis L.) oil produced VOCs on D. suzukii survival and the survival of and parasitism rates by a pupal parasitoid wasp, Pachycrepoideus vindemmiae (Rondani). First, we determined whether fumigation with peppermint oil VOCs at the pupal stage reduced adult emergence, and whether this depended on environmental conditions (i.e. soil moisture). Second, we evaluated whether fumigation with peppermint oil VOCs reduced or enhanced parasitism by the pupal parasitoid and whether this depended on the timing of peppermint oil VOC exposure (i.e. before, during, or after parasitoid access). Fumigation with VOCs of 4.5 mg of peppermint oil reduced D. suzukii emergence under moist soil conditions but dry soil had a similar effect on reducing adult emergence as peppermint oil presence. Peppermint oil VOC fumigation was toxic to adult P. vindemmiae, but developing P. vindemmiae were unaffected by peppermint oil VOC fumigation. Using peppermint essential oil as a fumigant may reduce D. suzukii emergence from the pupal stage. However, this could negatively impact P. vindemmiae dependent on the timing of application.

Multiscale Determinants Drive Parasitization of Drosophilidae by Hymenopteran Parasitoids in Agricultural Landscapes.

(1) The management of agricultural landscapes for pest suppression requires a thorough understanding of multiple determinants controlling their presence. We investigated the ecological preferences of indigenous parasitoids and their drosophilid hosts to understand the role of native parasitoids as biological control agents of the invasive frugivorous Drosophila suzukii. (2) Using data from an extensive field survey across different habitat types we analyzed the influence of abiotic and biotic factors on parasitoid and drosophilid communities at multiscale levels. (3) Eight parasitoid and 27 drosophilid species were identified. Thirty-four percent variation in drosophilid communities was explained by factors at the landscape scale, and 52% of significant variation of parasitoids by local distribution of three drosophilid species, mainly collected in woodland. Parasitoid communities were significantly influenced by microhabitat type (ground versus canopy) rather than habitat type. All parasitoids except Pachycrepoideus vindemmiae preferred the ground microhabitat. All parasitoids, with the exception of Trichopria drosophilae and Spalangia erythromera, displayed significant preferences among the drosophilid species used in the baited traps. (4) Since they can tolerate a broad range of habitat factors, altogether pupal parasitoids investigated in this study could play a role in biological control programs to suppress D. suzukii, but non-target effects have to be regarded.

Diversity of parasitoids associated with fruit flies on cultivated and wild plants in southern Togo

Fruit flies (Diptera: Tephritidae) are major constraints on the production and marketing of fruits in African tropical and subtropical countries. In a perspective to manage these fly pests, an inventory of parasitoids associated with fruit flies was carried out from 2009 to 2011 in southern Togo through various fruit incubations. Nine species of native hymenopteran parasitoids associated with eight fly species belonging to five genera Bactrocera, Ceratitis, Dacus, Trirhithrum and Zeugodacus were recovered. Trichopria sp. (Diapriidae) was the most abundant parasitoid. However, the numbers of Braconidae (Diachasmimorpha fullawayi Silvestri, Fopius caudatus Szepligeti and Asobara sp.), Figitidae (Aganaspis sp.), Pteromalidae (Pachycrepoideus vindemmiae Rondani and Spalangia sp.), Eulophidae (Tetrastichus giffardianus Silvestri) and Chalcididae (Dirhinus giffardii Silvestri) species were relatively low. The rate of parasitism of different species of recovered parasitoids ranged from 0.6 to 40%. This is an asset for future surveys in the center and northern regions and studies of interactions between fruit flies and their natural enemies in Togo.

Frugivorous flies and their parasitoids associated with native fruits in an urban area

This study aimed to know the species of frugivorous flies (Tephritidae and Lonchaeidae) and their parasitoids associated with fruits in home orchards. It was conducted in the Gurgueia Valley, municipality of Bom Jesus, Piauí, Brazil. Fruit collection was carried out from April to December 2016. A total of 959 fruits (12 kg) belonging to seven fruit species were sampled, such as acerola (Malpighia glabra), carambola (Averrhoa carambola), lime (Citrus aurantifolia), balsam pear (Momordica charantia), cherry of the Rio Grande (Eugenia involucrata), umbu-cajá (Spondias bahiensis), and purple mombin (Spondias purpurea). Only three among these species (acerola, umbu-cajá, and purple mombin) were host, with 2,770 frugivorous flies. Umbu-cajá hosted 316 specimens of Anastrepha obliqua, from which puparia have emerged 84 specimens of Opius bellus and four of Pachycrepoideus vindemmiae. Purple mombin hosted Ceratitis capitata (2,384 specimens), Neosilba pendula (69 specimens), and Anastrepha sp. (one male). Eleven specimens of Tetrastichus giffardianus emerged from the puparia of C. capitata. Acerola hosted only one female of C. capitata and six specimens of N. pendula. Ceratitis capitata and N. pendula were recorded for the first-time infesting fruits of purple mombin in Piauí. Tetrastichus giffardianus parasitizing C. capitata in purple mombin was first recorded in the state of Piauí. Pachycrepoideus vindemmiae is a new record in A. obliqua in umbu-cajá in Brazil.

Identification and Comparative Analysis of Venom Proteins in a Pupal Ectoparasitoid, Pachycrepoideus vindemmiae.

Parasitoid wasps inject venom containing complex bioactive compounds to regulate the immune response and development of host arthropods and sometime paralyze host arthropods. Although extensive studies have been conducted on the identification of venom proteins in larval parasitoids, relatively few studies have examined the pupal parasitoids. In our current study, a combination of transcriptomic and proteomic methods was used to identify 64 putative venom proteins from Pachycrepoideus vindemmiae, an ectoparasitoid of Drosophila. Expression analysis revealed that 20 tested venom proteins have 419-fold higher mean expression in the venom apparatus than in other wasp tissues, indicating their specialization to venom. Comparisons of venom proteins from P. vindemmiae and other five species spanning three parasitoid families detected a core set of “ancient” orthologs in Pteromalidae. Thirty-five venom proteins of P. vindemmiae were assigned to the orthologous groups by reciprocal best matches with venoms of other pteromalids, while the remaining 29 were not. Of the 35 categories, twenty-seven have orthologous relationships with Nasonia vitripennis venom proteins and 25 with venoms of Pteromalus puparum. More distant relationships detected that five and two venom proteins of P. vindemmiae are orthologous with venoms of two Figitidae parasitoids and a Braconidae representative, respectively. Moreover, twenty-two venoms unique to P. vindemmiae were also detected, indicating considerable interspecific variation of venom proteins in parasitoids. Phylogenetic reconstruction based on a set of single-copy genes clustered P. vindemmiae with P. puparum, N. vitripennis, and other members of the family Pteromalidae. These findings provide strong evidence that P. vindemmiae venom proteins are well positioned for future functional and evolutionary studies.

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The document associated with this DOI has been withdrawn.

Pupal parasitoids associated with Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) in a semiarid environment in Brazil

Fruit flies (Diptera: Tephritidae) are important pests that affect the fruit-growing worldwide. In the northeastern Brazil, where a semiarid climate predominates and the production of tropical fruits for export is concentrated, some fruit flies, including Anastrepha spp. and Ceratitis capitata (Wiedemann), are considered pests due to economic damage and quarantine restrictions. In several parts of the world, fruit fly population regulation is carried out with the support of hymenopteran parasitoids. In Brazil, some information exists about larval parasitoids of fruit flies, but little is known about pupal parasitoids of these tephritids, especially in Brazilian semiarid environments. Therefore, the main objective of this study was to know the pupal parasitoids associated with C. capitata in a semiarid environment in Brazil. The parasitoid survey was carried out in a semiarid region in the states of Rio do Norte and Ceará. To obtain the parasitoids, pupae (sentinels) of C. capitata from the laboratory, Applied Entomology Laboratory of Universidade Federal Rural do Semi-Árido, were exposed to natural parasitism in the field. Six parasitoid (Hymenoptera) species were obtained: Pachycrepoideus vindemmiae (Rondani), Spalangia simplex Perkins, Spalangia gemina Boucek, Spalangia leiopleura Gibson, and Spalangia impunctata Howard (Pteromalidae); Trichopria anastrephae Lima (Diapriidae). These are the first records of pupal parasitoids associated with the fruit fly C. capitata in Brazil.

WITHDRAWN

The document associated with this DOI has been withdrawn.

WITHDRAWN

The document associated with this DOI has been withdrawn.

WITHDRAWN

The document associated with this DOI has been withdrawn.

New records of the parasitoids of Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae) in newly invaded areas in Turkey: molecular identification

Drosophila suzukii (Matsumura, 1931) (Diptera: Drosophilidae) is an invasive pest species of various fruit crops in the USA and Europe. Although D. suzukii has been recently reported in strawberry in Erzurum and other newly invaded areas in Turkey (e.g., Ankara, Bolu, Canakkale and Duzce), there is only limited information on its indigenous parasitoids. In this study, four hymenopteran parasitoids, the larval parasitoids of Leptopilina boulardi (Barbotin, Carton & Kelner-Pillault, 1979), Leptopilina heterotoma (Thomson, 1862) (Figitidae) and the pupal parasitoids of Pachycrepoideus vindemmiae (Rondani, 1875) (Pteromalidae) and Trichopria drosophilae (Perkins, 1910) (Diapriidae), were collected from frugivorous drosophilid species. Leptopilina boulardi and T. drosophilae were found for the first time in Turkey. Leptopilina heterotoma and P. vindemmiae were the most common parasitoid species, reared from field-collected fruit samples in this study. The laboratory assays revealed that both pupal parasitoids developed from D. suzukii pupae, but the association of L. heterotoma and L. boulardi with D. suzukii is yet to be confirmed. The PCR amplification of the cytochrome c oxidase subunit I loci of mtDNA of the representative four parasitoid samples produced different lengths of DNA fragments, ranging from 633 bp to 658 bp. BLASTn queries based on the COI of the parasitoid samples showed that the sequences were 99-100% identical to those of the corresponding species in the GenBank database.

The Pupal Ectoparasitoid Pachycrepoideus vindemmiae Regulates Cellular and Humoral Immunity of Host Drosophila melanogaster.

The immunological interaction between Drosophila melanogaster and its larval parasitoids has been thoroughly investigated, however, little is known about the interaction between the host and its pupal parasitoids. Pachycrepoideus vindemmiae, a pupal ectoparasitoid of D. melanogaster, injects venom into its host while laying eggs on the puparium, which regulates host immunity and interrupts host development. To resist the invasion of parasitic wasps, various immune defense strategies have been developed in their hosts as a consequence of co-evolution. In this study, we mainly focused on the host immunomodulation by P. vindemmiae and thoroughly investigated cellular and humoral immune response, including cell adherence, cell viability, hemolymph melanization and the Toll, Imd, and JAK/STAT immune pathways. Our results indicated that venom had a significant inhibitory effect on lamellocyte adherence and induced plasmatocyte cell death. Venom injection and in vitro incubation strongly inhibited hemolymph melanization. More in-depth investigation revealed that the Toll and Imd immune pathways were immediately activated upon parasitization, followed by the JAK/STAT pathway, which was activated within the first 24 h post-parasitism. These regulatory effects were further validated by qPCR. Our present study manifested that P. vindemmiae regulated the cellular and humoral immune system of host D. melanogaster in many aspects. These findings lay the groundwork for studying the immunological interaction between D. melanogaster and its pupal parasitoid.

Toxicity of Bacterial Isolates on Adults of Zaprionus indianus (Diptera: Drosophilidae) and Parasitoids Trichopria anastrephae (Hymenoptera: Diapriidae) and Pachycrepoideus vindemmiae (Hymenoptera: Pteromalidae).

Bacillus thuringiensis (Berliner) has demonstrated potential use in insect pest management. We evaluated the toxicity and sublethal effects of formulations of toxic baits composed of bacterial isolates (Bt) B. thuringiensis var. oswaldo cruzi (Bto), B. thuringiensis var. israelensis (Bti), B. thuringiensis var. kurstaki (Btk), and B. circulars (Bc) in combination with three food attractants 50% grape juice, 7% sugar cane molasses, and 7% hydrolyzed protein on adults of Zaprionus indianus (Gupta, 1970), the main pest of fig fruit (Ficus carica) in Brazil. Likewise, we evaluated the toxicity on the parasitoids Trichopria anastrephae Lima, 1940 and Pachycrepoideus vindemmiae (Rondani, 1875) in ingestion bioassays. Adults of Z. indianus showed high susceptibility to Bacterial isolates. However, the Bto isolate (1013 CFU. ml-1) caused adult mortality of 100%, in 72 h after exposure, with LT50 values of ≈20 h. By using the lethal concentrations (LC90) of the Bto isolate, estimated via the concentration-response curves with the food attractants, a significant reduction (40 to 50%) in the total fecundity and in the embryonic viability of eggs from females fed with the toxic baits was observed. The food attractants + Bto (80 × 108 CFU. ml-1) did not cause significant mortality of T. anastrephae and P. vindemmiae adults (mortality < 20%). The bacterial isolates Bti, Btk, Bc, and Bto are considered promising for the formulation of toxic baits, because, besides providing toxic effect on adults of Z. indianus, they showed no toxicity on T. anastrephae and P. vindemmiae adults.

Factors affecting the biology of Pachycrepoideus vindemmiae (Hymenoptera: Pteromalidae), a parasitoid of spotted-wing drosophila (Drosophila suzukii).

Pachycrepoideus vindemmiae is a wasp that parasitizes and host-feeds on pupae of the invasive spotted-wing drosophila (SWD, Drosophila suzukii). Few studies have addressed interactions between these two species and little is known about the potential of this parasitoid as a biocontrol agent of SWD and the different variables that may affect it. Here, we investigated the impact of extrinsic and intrinsic factors on life-history traits of P. vindemmiae. Both constant (entire adulthood) and limited (30 minutes) supplies of water + honey, honey, or host increased parasitoid survival compared to controls (water or fasting). Water + honey caused the highest parasitoid survivals (35-60 days), independent of supply period, sex, and host availability. Females were intrinsically more resistant to water- and honey-deprivation than males, and host-feeding elevated such resistance even higher. Constant honey supply (either with or without water) supported the highest host-killing capacities (= capacity to kill hosts) (ca. 600 SWD pupae/wasp). However, in young females (4-9 days old), the impact of honey availability (with or without water) was insignificant while water deprivation (either with or without honey) caused the highest host-killing potential. This indicates that although sugar becomes a critical nutritional resource as females age, young females depend more on water than sugar to reproduce. Neither water nor honey affected the sex ratio of young females, but when we considered the entire adulthood, the availability of honey caused the lowest proportion of females (0.50), independent of water availability. Neither water nor honey affected parasitoid emergence rate (0.97), independent of female age. Based on survival and host-killing capacity, we conclude that P. vindemmiae has a tremendous biocontrol potential against SWD. Both limited and constant supply of water, sugar, and host increase parasitoid survival, while constant supply of water and/or honey enhance its host-killing potential and decrease sex ratio depending on maternal age.

Ability of Muscidifurax raptorellus and Other Parasitoids and Predators to Control Drosophila suzukii Populations in Raspberries in the Laboratory.

Drosophila suzukii is an invasive pest and economic threat to berry crops in Europe and the Americas. Current methods of control of this pest rely primarily on frequent applications of insecticides; therefore, there is a need for alternative control methods to reduce insecticide reliance. In this study, we evaluated the biological control potential of three parasitoid wasps: Diglyphus isaea, Muscidifurax raptorellus and Pachycrepoideus vindemmiae, and four predators: Chrysoperla carnea, Dicyphus hesperus, Orius insidiosus and Podisus maculiventris. Experiments were conducted for 15 days under controlled conditions in experimental arenas with D. suzukii females and raspberries, allowing for all life stages of D. suzukii to be available to natural enemies. Results showed the first evidence of M. raptorellus’s ability to parasitize D. suzukii, resulting in a 40% reduction. Orius insidiosus, P. vindemmiae and C. carnea were also efficient, reducing D. suzukii numbers by 49%, 43% and 32%, respectively. Predator preferences for each D. suzukii life stage were assessed. The clutch size, sex ratio and adult size variability of D. suzukii pupal parasitoids were also evaluated. This study expands the list of species that can effectively parasitize D. suzukii and provides new insights into the biological responses of M. raptorellus to D. suzukii pupae.

Water-Deprived Parasitic Wasps (Pachycrepoideus vindemmiae) Kill More Pupae of a Pest (Drosophila suzukii) as a Water-Intake Strategy

Most organisms must ingest water to compensate for dehydration. In parasitic wasps, the importance of water and the behaviors driving its consumption are poorly understood. Here, we describe a water-intake strategy of Pachycrepoideus vindemmiae, a parasitoid of spotted-wing drosophila (SWD, Drosophila suzukii). Longevity measurements indicated that P. vindemmiae benefits from drinking water and from host-feeding on the water-rich hemolymph of SWD pupae. After exposing wasps to different water regimens, we observed increased host-feeding in water-deprived wasps despite honey availability. This resulted in greater SWD mortality because the host-feeding process killed the pupae, and because wasps that engaged in greater host-feeding parasitized more hosts. Behavioral observations showed that the host-feeding time of water-deprived wasps doubled compared to water-fed individuals. Host-feeding did not affect parasitoid offspring mortality. We conclude that P. vindemmiae benefits from ingesting water and that it host-feeds on SWD pupae as a water-intake strategy. These are interesting findings not only because water has rarely been reported as a critical nutrient for adult parasitoids, but especially because preying for the purpose of hydration is not a common strategy in nature. This strategy enhances parasitoid survival and reproduction, with positive consequences for its host-killing capacity and potential as a biocontrol agent.

Insecticide Toxicity to Drosophila suzukii (Diptera: Drosophilidae) parasitoids: Trichopria anastrephae (Hymenoptera: Diapriidae) and Pachycrepoideus vindemmiae (Hymenoptera: Pteromalidae).

Drosophila suzukii (Matsumura) is an important pest of small fruits, which has been causing significant damage to commercial crops in North America, Europe, and South America. This pest is mainly controlled with insecticide applications because of its highly biotic potential and polyphagy. However, studies conducted in crops infested by D. suzukii have shown that this species is attacked by parasitoids that may serve as effective biological controls for this pest. The aim of the current study is to assess the lethal time (LT10 and LT50) and parasitism potential of exposed adults (F0): sex ratio and longevity (F1) of Trichopria anastrephae Lima and Pachycrepoideus vindemmiae (Rondani) when exposed to dry residues of different commercial insecticides. Abamectin, acetamiprid, thiamethoxam, malathion, phosmet, deltamethrin, spinetoram, and spinosad were evaluated. Pachycrepoideus vindemmiae was more sensitive to insecticides than T. anastrephae, showing higher mortality rates in a shorter period of time, as well as a significant reduction in parasitism. Spinosyns (spinosad and spinetoram) and abamectin caused high P. vindemmiae mortality rates, but were harmless to T. anastrephae. Neonicotinoids, organophosphates, and pyrethroids caused high mortality rates regardless of the species. Treatments did not affect D. suzukii offspring longevity and sex ratio (F1). The current study provides information needed for the implementation of D. suzukii management programs focused on the conservation of natural enemies.