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željko Tomanovic - One of the best experts on this subject based on the ideXlab platform.
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resolving the taxonomic status of biocontrol agents belonging to the Aphidius eadyi species group hymenoptera braconidae aphidiinae an integrative approach
Bulletin of Entomological Research, 2019Co-Authors: Andjeljko Petrovic, Petr Starý, Nickolas G. Kavallieratos, Ana Ivanovic, Milana Mitrovic, M E Ghaliow, željko TomanovicAbstract:Species that belong to the Aphidius eadyi group have been used as biocontrol agents against Acyrthosiphon pisum worldwide. However, despite their extensive use, there are still gaps in our knowledge about their taxonomy and distribution. In this study, we employed an integrative taxonomic approach by combining genetic analyses (mtDNA COI barcoding) with standard morphological analyses and geometric morphometrics of forewing shape. We identified three species within the A. eadyi species group, viz., A. smithi, A. eadyi and A. banksae. Genetic separation of all three species was confirmed, with mean genetic distances between species ranging from 5 to 7.4%. The following morphological characters were determined as the most important for separating species of the A. eadyi group: number and shape of costulae on the anterolateral part of the petiole, shape of the central areola on the propodeum, and shape and venation of the forewings. The differences in wing shape of all three species were statistically significant, but with some overlapping. We identified A. banksae as a widely distributed pea aphid parasitoid, whose known range covers most of the western Palaearctic (from the UK to Israel). Aphidius banksae is diagnosed and redescribed.
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Neighbour joining tree of parasitoid species within the Aphidiinae based on sequences of the 5’-region of the cytochrome c oxidase I gene (COI).
2017Co-Authors: Ines M. G. Vollhardt, željko Tomanovic, Michael TraugottAbstract:Bootstrap values (≥ 70%) are indicated on branches. Identical sequences and subtrees with all bootstrap values less than 70% within one species were clustered. Numbers in parentheses refer to the number of sequences include in each cluster. Species abbreviations: Adialytus ambiguus (ADamb), Aphidius avenae (APave), Aphidius colemani (APcol), Aphidius ervi (APerv), Aphidius matricariae (APmat), Aphidius microlophii (APmic), Aphidius rhopalosiphi (APrho), Aphidius uzbekistanicus (APuzb), Binodoxys angelicae (BIang), Diaeretiella rapae (DIrap), Ephedrus persicae (EPper) Ephedrus plagiator (EPpla), Lipolexis gracilis (LIgra), Lysiphlebus fabarum (LYfab), Lysiphlebus testaceipes (LYtes), Monoctonus crepidis (MOcre), Praon abjectum (PRabj), Praon gallicum (PRgal), Praon necans (PRnec), Praon volucre (PRvol), Toxares deltiger (TOdel), Trioxys auctus (TRaus) and Trioxys sp. A (TRspA). Last letter in the specimen code indicates whether sequencing was done in both directions (“B”) or just one direction (“S”—sense strand, “A”—antisense stand).
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Molecular and morphological variability within the Aphidius colemani group with redescription of Aphidius platensis Brethes (Hymenoptera: Braconidae: Aphidiinae).
Bulletin of entomological research, 2014Co-Authors: željko Tomanovic, Petr Starý, Andjeljko Petrović, Milana Mitrović, Nickolas G. Kavallieratos, Ehsan Rakhshani, Rakhshanipour M, Anđelka Popović, A.h. Shukshuk, Ana IvanovićAbstract:We have identified the following three taxa related to the Aphidius colemani species group, which are important biological control agents: Aphidius colemani, Aphidius transcaspicus and Aphidius platensis. Using partial sequences of the mitochondrial cytochrome oxidase subunit I (mtCOI) gene and geometric morphometric analysis of the forewing shape, we have explored the genetic structure and morphological variability of the A. colemani group from different aphid host/plant associations covering a wide distribution area. The topology of the maximum parsimony and maximum likelihood trees were identical with 98-100% bootstrap support, clustering A. colemani, A. platensis and A. transcaspicus into separate species. The distances among the taxa ranged from 2.2 to 4.7%, which is a common rate for the between-species divergence within the subfamily Aphidiinae. Differences in the shape of the forewing investigated within the biotypes of A. colemani group are congruent with their genetic diversification. Both A. platensis and A. colemani share a common host range pattern, and it would be interesting to estimate and compare the role of these two species in future biological control strategies against aphids of economic importance. Our results indicate that 'genetic screening' is a reliable approach for identification within the A. colemani group. The high variation in the wing shape among species, including a significant divergence in the wing shape among specimens that emerged from different hosts, makes the forewing shape and wing venation less reliable for species determination. Aphidius platensis is diagnostified and redescribed, and the key for the A. colemani group is presented.
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the relationship between molecular variation and variation in the wing shape of three aphid parasitoid species Aphidius uzbekistanicus luzhetzki Aphidius rhopalosiphi de stefani perez and Aphidius avenaphis fitch hymenoptera braconidae aphidiinae
Zoologischer Anzeiger – A Journal of Comparative Zoology, 2013Co-Authors: željko Tomanovic, Stanislav Trdan, Petr Starý, Nickolas G. Kavallieratos, Katarina Kos, Andjeljko Petrovic, Jernej Jakse, Vladimir žikic, Ana IvanovicAbstract:Abstract This paper examines the relationship between molecular and phenotypic variability among three closely related cereal aphid parasitoids: Aphidius rhopalosiphi and Aphidius uzbekistanicus from Euro-Asia and Aphidius avenaphis from North America. A. rhopalosiphi has the same distribution and shares the same aphid hosts as A. uzbekistanicus . The genetic variation of these parasitoids was explored using a barcoding area of the mitochondrial COI gene. Phenotypic variability based on the wing shape and stigma shape was explored using geometric morphometrics. Molecular analyses revealed the existence of two distinct clades: the A. rhopalosiphi clade, which is characterized by a high level of within-clade genetic variation, and the A. uzbekistanicus/A. avenaphis clade, which has almost no variation at the barcoding area of the mitochondrial COI gene. Generally, a high level of variation in wing shape has been shown within populations of both clades. Our results indicate that there is no relationship between the level of the variation at the barcoding area of the mitochondrial COI gene and the level of morphological variation. The genetically uniform A. uzbekistanicus/A. avenaphis clade had even greater variation in stigma shape than A. rhopalosiphi clade, which is characterized by a high level of genetic variation.
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on the identity of cereal aphid parasitoid wasps Aphidius uzbekistanicus Aphidius rhopalosiphi and Aphidius avenaphis hymenoptera braconidae aphidiinae by examination of coi mitochondrial gene geometric morphometrics and morphology
Annals of The Entomological Society of America, 2011Co-Authors: Katarina Kos, Stanislav Trdan, Petr Starý, Nickolas G. Kavallieratos, Andjeljko Petrovic, Ana Ivanovic, I Tosevski, Jernej Jakse, željko TomanovicAbstract:ABSTRACT In this study, the relationships among and the taxonomic status of three closely related parasitic wasps that are widely used as biological control agents of cereal aphids, Aphidius uzbekistanicus Luzhetzki, Aphidius rhopalosiphi De Stefani Perez, and Aphidius avenaphis (Fitch), were examined. Genetic divergence at an average of 6% was recorded between A. uzbekistanicus and A. rhopalosiphi by using the mitochondrial (mt) gene cytochrome oxidase I (COI) barcoding region. Identical mtCOI gene sequences were observed in A. uzbekistanicus specimens that originated from Eurasia and in the North American species A. avenaphis. The haplotype fluctuation in A. rhopalosiphi specimens that originated from the west Palaearctic was an average of 1.5% (maximum, 2.4%). In contrast, specimens of A. uzbekistanicus from central and western parts of Eurasia were largely homogenous, with only a single mutation recorded in a specimen from eastern Europe (Serbia). The morphological and genetic diversity found in A. rh...
Maggie Levy - One of the best experts on this subject based on the ideXlab platform.
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pseudozyma aphidis activates reactive oxygen species production programmed cell death and morphological alterations in the necrotrophic fungus botrytis cinerea
Molecular Plant Pathology, 2019Co-Authors: Claudia E Calderon, Raviv Harris, Neta Rotem, David Velacorcia, Maggie LevyAbstract:Many types of yeast have been studied in the last few years as potential biocontrol agents against different phytopathogenic fungi. Their ability to control plant diseases is mainly through combined modes of action. Among them, antibiosis, competition for nutrients and niches, induction of systemic resistance in plants and mycoparasitism have been the most studied. In previous work, we have established that the epiphytic yeast Pseudozyma aphidis inhibits Botrytis cinerea through induced resistance and antibiosis. Here, we demonstrate that P. aphidis adheres to B. cinerea hyphae and competes with them for nutrients. We further show that the secreted antifungal compounds activate the production of reactive oxygen species and programmed cell death in B. cinerea mycelium. Finally, P. aphidis and its secreted compounds negatively affect B. cinerea hyphae, leading to morphological alterations, including hyphal curliness, vacuolization and branching, which presumably affects the colonization ability and infectivity of B. cinerea. This study demonstrates additional modes of action for P. aphidis and its antifungal compounds against the plant pathogen B. cinerea.
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pseudozyma aphidis induces salicylic acid independent resistance to clavibacter michiganensis in tomato plants
Plant Disease, 2015Co-Authors: Omer Barda, Or Shalev, Shanee Alster, Kobi Buxdorf, Aviva Gafni, Maggie LevyAbstract:The ability of plant pathogens to rapidly develop resistance to commonly used pesticides challenges efforts to maximize crop production. Fungal biocontrol agents have become an important alternative to chemical fungicides as a result of environmental concerns regarding conventional pesticides, including resistance issues. The complex mode of action of biocontrol agents reduces the likelihood that pathogens will develop resistance to them. We recently isolated a unique, biologically active isolate of the epiphytic fungus Pseudozyma aphidis. We show that the extracellular metabolites secreted by our P. aphidis isolate can inhibit Xanthomonas campestris pv. vesicatoria, X. campestris pv. campestris, Pseudomonas syringae pv. tomato, Erwinia amylovora, Clavibacter michiganensis, and Agrobacterium tumefaciens in vitro. Moreover, application of Pseudozyma aphidis spores on tomato plants in the greenhouse significantly reduced (by 60%) the incidence of bacterial wilt and canker disease caused by C. michiganensis ...
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biological control of the cucurbit powdery mildew pathogen podosphaera xanthii by means of the epiphytic fungus pseudozyma aphidis and parasitism as a mode of action
Frontiers in Plant Science, 2015Co-Authors: Aviva Gafni, Kobi Buxdorf, Claudia E Calderon, Raviv Harris, Avis Dafaberger, Einat Zeilingerreichert, Maggie LevyAbstract:Epiphytic yeasts, which colonize plant surfaces, may possess activity that can be harnessed to help plants defend themselves against various pathogens. Due to their unique characteristics, epiphytic yeasts belonging to the genus Pseudozyma hold great potential for use as biocontrol agents. We identified a unique, biologically active isolate of the epiphytic yeast Pseudozyma aphidis that is capable of inhibiting Botrytis cinerea via a dual mode of action, namely induced resistance and antibiosis. Here, we show that strain L12 of P. aphidis can reduce the severity of powdery mildew caused by Podosphaera xanthii on cucumber plants with an efficacy of 75%. Confocal and scanning electron microscopy analyses demonstrated P. aphidis proliferation on infected tissue and its production of long hyphae that parasitize the powdery mildew hyphae and spores as an ectoparasite. We also show that crude extract of P. aphidis metabolites can inhibit P. xanthii spore germination in planta. Our results suggest that in addition to its antibiosis mode of action, P. aphidis may also act as an ectoparasite on P. xanthii. These results indicate that P. aphidis strain L12 has the potential to control powdery mildew.
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the epiphytic fungus pseudozyma aphidis induces jasmonic acid and salicylic acid nonexpressor of pr1 independent local and systemic resistance
Plant Physiology, 2013Co-Authors: Kobi Buxdorf, Aviva Gafni, Ido Rahat, Maggie LevyAbstract:Pseudozyma spp. are yeast-like fungi, classified in the Ustilaginales, which are mostly epiphytic or saprophytic and are not pathogenic to plants. Several Pseudozyma species have been reported to exhibit biological activity against powdery mildews. However, previous studies have reported that Pseudozyma aphidis, which can colonize plant surfaces, is not associated with the collapse of powdery mildew colonies. In this report, we describe a novel P. aphidis strain and study its interactions with its plant host and the plant pathogen Botrytis cinerea. This isolate was found to secrete extracellular metabolites that inhibit various fungal pathogens in vitro and significantly reduce B. cinerea infection in vivo. Moreover, P. aphidis sensitized Arabidopsis (Arabidopsis thaliana) plants’ defense machinery via local and systemic induction of PATHOGENESIS-RELATED1 (PR1) and PLANT DEFENSIN1.2 (PDF1.2) expression. P. aphidis also reduced B. cinerea infection, locally and systemically, in Arabidopsis mutants impaired in jasmonic acid (JA) or salicylic acid (SA) signaling. Thus, in addition to direct inhibition, P. aphidis may inhibit B. cinerea infection via induced resistance in a manner independent of SA, JA, and Nonexpressor of PR1 (NPR1). P. aphidis primed the plant defense machinery and induced stronger activation of PDF1.2 after B. cinerea infection. Finally, P. aphidis fully or partially reconstituted PR1 and PDF1.2 expression in npr1-1 mutant and in plants with the SA hydroxylase NahG transgene, but not in a jasmonate resistant1-1 mutant, after B. cinerea infection, suggesting that P. aphidis can bypass the SA/NPR1, but not JA, pathway to activate PR genes. Thus, either partial gene activation is sufficient to induce resistance, or the resistance is not directed solely through PR1 and PDF1.2 but probably through other pathogen-resistance genes or pathways as well.
Francesco Pennacchio - One of the best experts on this subject based on the ideXlab platform.
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an artificial aphid for Aphidius ervi hym braconidae
Journal of Applied Entomology, 2005Co-Authors: Anna Larocca, Francesco Pennacchio, Paolo Fanti, V A Romano, E Marsicovetere, Donatella BattagliaAbstract:: An artificial aphid was developed by making parafilm® bubbles filled with aphid haemolymph and its suitability for parasitoid oviposition was tested. Aphidius ervi accepted the parafilm® aphid and laid eggs on it. By stretching, the thickness of the parafilm could be changed. The thicker the parafilm, the higher was the mean number of ovipositional stings and the lower the mean number of eggs released by A. ervi.
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nutrient absorption by Aphidius ervi larvae
Journal of Insect Physiology, 2005Co-Authors: Silvia Caccia, Francesco Pennacchio, M G Leonardi, Morena Casartelli, A Grimaldi, Magda De Eguileor, Barbara GiordanaAbstract:Abstract It is well documented that in the model system Aphidius ervi Haliday (Hymenoptera, Braconidae)/Acyrthosiphon pisum (Harris) (Homoptera, Aphididae) host regulation by the parasitoid larva induces in the aphid haemolymph major changes of the titer of nutritional compounds such as proteins, acylglycerols and free amino acids, in order to meet the stage-specific demands of the developing larva. Since little is known about how the larva absorbs these mobilized nutritional resources, nutrient absorption by larval stages of A. ervi was studied. In 2nd instar larvae, leucine was ten-fold accumulated in the haemocoel, and tyrosine and glutamine two-fold. Glucose and fructose were readily absorbed and fructose was extensively metabolized by larval tissues. In 3rd instars, the presence of a number of larvae that did not ingest the incubation medium enabled us to determine the respective amounts of substrate absorbed by the epidermis and the midgut. An accumulation of leucine in the haemocoel was observed only when midgut cells were involved in absorption, while the amino acid concentration within body fluids never exceeded that of the incubation medium when the uptake was performed only by epidermal cells. The immunofluorescence analysis, the mutual inhibition exerted on labeled glucose or fructose uptakes by a 100-fold excess of the sugars and the strong inhibition of uptakes induced by 0.2 mM cytochalasin B support the expression of facilitative GLUT2-like transporters in the apical and basal cell membranes of midgut epithelial cells. Taken together, these results prove that both midgut and epidermis are involved in nutrient absorption throughout the parasitoid development, that GLUT2 transporters are responsible for glucose and fructose uptakes and that the chemical gradient that favors the passive influx of the two sugars is maintained by their conversion to other substrates.
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characterization of Aphidius ervi hymenoptera braconidae ribosomal genes and identification of site specific insertion elements belonging to the non ltr retrotransposon family
Insect Biochemistry and Molecular Biology, 1995Co-Authors: Paola Varricchio, Francesco Pennacchio, E Tremblay, Franco Graziani, Giuseppe Gargiulo, Alessandro Manzi, Maria Cristina Digilio, C MalvaAbstract:We performed a molecular analysis of the Aphidius ervi ribosomal gene structure. This insect belongs to a set of closely related Aphidiinae species of the genus Aphidius Nees, of relevant interest in biological control. We constructed A. ervi genomic libraries, cloned and characterized several rDNA repeating units and sequenced different regions of the rDNA cistrons. We have found that insertion sequences interrupt the A. ervi 28S rDNA genes: the sequences of the two 5′ and 3′ insertion-28S junctions show that the elements are present at the position where R1 elements have been found in various insect species. In addition, the insertion of the element produces a duplication of the 14 nt target region. The sequence analysis indicates that the A. ervi elements belong to the R1 retrotransposon family with a highly conserved reverse transcriptase domain.
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host recognition and acceptance behaviour in two aphid parasitoid species Aphidius ervi and Aphidius microlophii hymenoptera braconidae
Bulletin of Entomological Research, 1994Co-Authors: Francesco Pennacchio, E Tremblay, Maria Cristina Digilio, A TranfagliaAbstract:The host preference and acceptance behaviour of populations of Aphidius ervi Haliday and A. microlophii Pennacchio & Tremblay from southern Italy was investigated. In no host-choice conditions, A. ervi females showed significantly higher attack and oviposition rates on the natural host Acyrthosiphon pisum (Harris) than on the non-host aphid Microlophium carnosum (Buckton)(Homoptera: Aphididae). In contrast, A. microlophii , which specifically parasitizes M. carnosum in the field, attacked both aphid species. However, dissections showed that oviposition of A. microlophii occurred only in a few of the attacked Acyrthosiphon pisum and was significantly less frequent than in M. carnosum . These results were confirmed in experimental host-choice conditions, suggesting that Aphidius microlophii oviposition is possibly regulated by a host haemolymphatic kairomone. Hybrids obtained by crossing A. ervi females with A. microlophii males attacked and oviposited in both aphid species, suggesting that these behavioural events have a strong genetic basis. The oviposition into host or non-host aphids did not elicit an immune defence reaction. The presence of the host's food-plant had no evident close-range effects on parasitoid attack and oviposition in non-host aphids. Aphidius microlophii reared on the non-host aphid Acyrthosiphon pisum produced a significant higher number of mummies after a few generations, suggesting a possible role of larval and early adult conditioning in the host selection process. These results, together with those from previous studies, suggest that Aphidius ervi is best considered as a complex of differentiated populations, characterized by a varying degree of genetic divergence.
Petr Starý - One of the best experts on this subject based on the ideXlab platform.
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resolving the taxonomic status of biocontrol agents belonging to the Aphidius eadyi species group hymenoptera braconidae aphidiinae an integrative approach
Bulletin of Entomological Research, 2019Co-Authors: Andjeljko Petrovic, Petr Starý, Nickolas G. Kavallieratos, Ana Ivanovic, Milana Mitrovic, M E Ghaliow, željko TomanovicAbstract:Species that belong to the Aphidius eadyi group have been used as biocontrol agents against Acyrthosiphon pisum worldwide. However, despite their extensive use, there are still gaps in our knowledge about their taxonomy and distribution. In this study, we employed an integrative taxonomic approach by combining genetic analyses (mtDNA COI barcoding) with standard morphological analyses and geometric morphometrics of forewing shape. We identified three species within the A. eadyi species group, viz., A. smithi, A. eadyi and A. banksae. Genetic separation of all three species was confirmed, with mean genetic distances between species ranging from 5 to 7.4%. The following morphological characters were determined as the most important for separating species of the A. eadyi group: number and shape of costulae on the anterolateral part of the petiole, shape of the central areola on the propodeum, and shape and venation of the forewings. The differences in wing shape of all three species were statistically significant, but with some overlapping. We identified A. banksae as a widely distributed pea aphid parasitoid, whose known range covers most of the western Palaearctic (from the UK to Israel). Aphidius banksae is diagnosed and redescribed.
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checklist of aphidiinae hymenoptera braconidae and aphelinus hymenoptera aphelinidae species from belgium with respectively four and three new records
Zootaxa, 2016Co-Authors: Thomas Chevalier Mendes Lopes, Petr Starý, Pierrenicolas Libert, George Japoshvili, Severin Hatt, Frederic FrancisAbstract:Aphid parasitoids have good potential for crop protection. However, they have been poorly studied in Belgium, especially in terms of species diversity. Therefore, the aim of this work was to establish the first checklist for the country. To complete the list, aphid parasitoids were sampled in wheat and pea fields near Gembloux (Belgium), in 2013 and 2014. Among the identified species, Aphelinus asychis Walker, Aphelinus daucicola Kurdjumov, Aphelinus fusciscapus (Forster), Aphidius asteris Haliday, Aphidius eadyi Starý, Gonzalez & Hall, Praon barbatum Mackauer, and Trioxys auctus (Haliday) were recorded for the first time in Belgium. Thirty-two Aphidiinae and seven Aphelinus species were included in the checklist. It is hoped this study will stimulate further research, as species diversity is still low compared with neighbouring countries.
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Molecular and morphological variability within the Aphidius colemani group with redescription of Aphidius platensis Brethes (Hymenoptera: Braconidae: Aphidiinae).
Bulletin of entomological research, 2014Co-Authors: željko Tomanovic, Petr Starý, Andjeljko Petrović, Milana Mitrović, Nickolas G. Kavallieratos, Ehsan Rakhshani, Rakhshanipour M, Anđelka Popović, A.h. Shukshuk, Ana IvanovićAbstract:We have identified the following three taxa related to the Aphidius colemani species group, which are important biological control agents: Aphidius colemani, Aphidius transcaspicus and Aphidius platensis. Using partial sequences of the mitochondrial cytochrome oxidase subunit I (mtCOI) gene and geometric morphometric analysis of the forewing shape, we have explored the genetic structure and morphological variability of the A. colemani group from different aphid host/plant associations covering a wide distribution area. The topology of the maximum parsimony and maximum likelihood trees were identical with 98-100% bootstrap support, clustering A. colemani, A. platensis and A. transcaspicus into separate species. The distances among the taxa ranged from 2.2 to 4.7%, which is a common rate for the between-species divergence within the subfamily Aphidiinae. Differences in the shape of the forewing investigated within the biotypes of A. colemani group are congruent with their genetic diversification. Both A. platensis and A. colemani share a common host range pattern, and it would be interesting to estimate and compare the role of these two species in future biological control strategies against aphids of economic importance. Our results indicate that 'genetic screening' is a reliable approach for identification within the A. colemani group. The high variation in the wing shape among species, including a significant divergence in the wing shape among specimens that emerged from different hosts, makes the forewing shape and wing venation less reliable for species determination. Aphidius platensis is diagnostified and redescribed, and the key for the A. colemani group is presented.
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the relationship between molecular variation and variation in the wing shape of three aphid parasitoid species Aphidius uzbekistanicus luzhetzki Aphidius rhopalosiphi de stefani perez and Aphidius avenaphis fitch hymenoptera braconidae aphidiinae
Zoologischer Anzeiger – A Journal of Comparative Zoology, 2013Co-Authors: željko Tomanovic, Stanislav Trdan, Petr Starý, Nickolas G. Kavallieratos, Katarina Kos, Andjeljko Petrovic, Jernej Jakse, Vladimir žikic, Ana IvanovicAbstract:Abstract This paper examines the relationship between molecular and phenotypic variability among three closely related cereal aphid parasitoids: Aphidius rhopalosiphi and Aphidius uzbekistanicus from Euro-Asia and Aphidius avenaphis from North America. A. rhopalosiphi has the same distribution and shares the same aphid hosts as A. uzbekistanicus . The genetic variation of these parasitoids was explored using a barcoding area of the mitochondrial COI gene. Phenotypic variability based on the wing shape and stigma shape was explored using geometric morphometrics. Molecular analyses revealed the existence of two distinct clades: the A. rhopalosiphi clade, which is characterized by a high level of within-clade genetic variation, and the A. uzbekistanicus/A. avenaphis clade, which has almost no variation at the barcoding area of the mitochondrial COI gene. Generally, a high level of variation in wing shape has been shown within populations of both clades. Our results indicate that there is no relationship between the level of the variation at the barcoding area of the mitochondrial COI gene and the level of morphological variation. The genetically uniform A. uzbekistanicus/A. avenaphis clade had even greater variation in stigma shape than A. rhopalosiphi clade, which is characterized by a high level of genetic variation.
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on the identity of cereal aphid parasitoid wasps Aphidius uzbekistanicus Aphidius rhopalosiphi and Aphidius avenaphis hymenoptera braconidae aphidiinae by examination of coi mitochondrial gene geometric morphometrics and morphology
Annals of The Entomological Society of America, 2011Co-Authors: Katarina Kos, Stanislav Trdan, Petr Starý, Nickolas G. Kavallieratos, Andjeljko Petrovic, Ana Ivanovic, I Tosevski, Jernej Jakse, željko TomanovicAbstract:ABSTRACT In this study, the relationships among and the taxonomic status of three closely related parasitic wasps that are widely used as biological control agents of cereal aphids, Aphidius uzbekistanicus Luzhetzki, Aphidius rhopalosiphi De Stefani Perez, and Aphidius avenaphis (Fitch), were examined. Genetic divergence at an average of 6% was recorded between A. uzbekistanicus and A. rhopalosiphi by using the mitochondrial (mt) gene cytochrome oxidase I (COI) barcoding region. Identical mtCOI gene sequences were observed in A. uzbekistanicus specimens that originated from Eurasia and in the North American species A. avenaphis. The haplotype fluctuation in A. rhopalosiphi specimens that originated from the west Palaearctic was an average of 1.5% (maximum, 2.4%). In contrast, specimens of A. uzbekistanicus from central and western parts of Eurasia were largely homogenous, with only a single mutation recorded in a specimen from eastern Europe (Serbia). The morphological and genetic diversity found in A. rh...
W. Powell - One of the best experts on this subject based on the ideXlab platform.
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learning is involved in the response of parasitic wasps Aphidius ervi haliday hymenoptera braconidae to volatiles from a broad bean plant vicia faba fabaceae infested by aphids acyrthosiphon pisum harris homoptera aphididae
Applied Entomology and Zoology, 2009Co-Authors: Hiroyuki Takemoto, W. Powell, Yooichi Kainoh, J. A. Pickett, Junji TakabayashiAbstract:It has been reported that volatiles from broad bean plants, Vicia faba (cv. ‘the Sutton’) infested by the pea aphid, Acyrthosiphon pisum, attract a specialist parasitoid Aphidius ervi, collected from populations in England, Italy and Bulgaria, which had no previous experience of the host-infested plant volatiles. Aphidius ervi collected in Hokkaido, Japan were also attracted to volatiles from host-infested broad bean plants (cv. ‘Nintoku Issun’) in preference to those from intact plants in a Y-tube olfactometer when the wasps were allowed to emerge on the infested plants, but wasps that had emerged in a clean Petri dish showed no significant choice between the two odor sources. When artificially exposed to the infested plant volatiles during emergence from the mummy, the wasps showed a significant preference for infested plant volatiles over those from intact plants. In further studies in a wind tunnel, significantly more wasps landed on infested plants than on intact plants when wasps were exposed to infested plant volatiles. Naive wasps, however, did not show a higher landing response to infested plants. These data suggest that learning is required by A. ervi of the Hokkaido strain for their response to infested plant volatiles in their host searching behavior.
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chemically mediated intraguild predator avoidance by aphid parasitoids interspecific variability in sensitivity to semiochemical trails of ladybird predators
Journal of Chemical Ecology, 2006Co-Authors: Yoshitaka Nakashima, Michael A Birkett, B J Pye, W. PowellAbstract:The avoidance responses of aphid parasitoids with varying host ranges (Aphidius eadyi, Aphidius ervi, and Praon volucre) to chemical trails deposited by intraguild predatory ladybirds, Coccinella septempunctata and Adalia bipunctata, were investigated. Females of all three parasitoid species avoided leaves previously visited by C. septempunctata or A. bipunctata adults. The avoidance responses shown by the two Aphidius species were stronger to trails of C. septempunctata than to those of A. bipunctata. However, P. volucre avoided trails of both ladybird species to a similar degree. Dose responses of these three parasitoid species to the hydrocarbons n-tricosane (C23H48), n-pentacosane (C25H52), and n-heptacosane (C27H56), which are components of the trails of both C. septempunctata and A. bipunctata, were evaluated. Dual-choice bioassays indicated the following: (1) A. eadyi showed more sensitive avoidance responses to n-tricosane than did the other two parasitoid species, (2) all three species showed similar responses to n-pentacosane across a range of doses, and (3) only P. volucre showed avoidance responses to n-heptacosane. Quantitative analyses of each hydrocarbon in the trails of the two ladybird species showed that n-pentacosane and n-heptacosane occur in significantly greater amounts in C. septempunctata trails than in those of A. bipunctata. The trails of the two species also differ qualitatively in the other hydrocarbons present.
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responses to aphid sex pheromones by the pea aphid parasitoids Aphidius ervi and Aphidius eadyi
Entomologia Experimentalis Et Applicata, 1999Co-Authors: Robert Glinwood, Y J Du, W. PowellAbstract:Aphidius ervi and Aphidius eadyi, two parasitoids of the pea aphid Acyrthosiphon pisum, were attracted to components of the aphid sex pheromone in laboratory bioassays. Pre-test experience with host aphids in the presence of aphid sex pheromone did not affect the response of A. ervi to pheromone in a 4-way olfactometer, compared with that of naive parasitoids. Aphidius ervi females exposed only to the pheromone prior to testing did not respond in the olfactometer, suggesting habituation to the foraging cue by the parasitoid. In a wind tunnel, aphid sex pheromone increased the attraction of A. ervi to the plant-host complex (Vicia faba/A. pisum), suggesting an additive effect when two different foraging cues are present simultaneously.