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Mustafa Yaman - One of the best experts on this subject based on the ideXlab platform.

Renate Radek - One of the best experts on this subject based on the ideXlab platform.

  • A MICROSPORIDIAN PATHOGEN OF THE PREDATORY BEETLE RHIZOPHAGUS GRANDIS (COLEOPTERA: RHIZOPHAGIDAE)
    2016
    Co-Authors: Mustafa Yaman, Renate Radek, Jaroslav Weiser, Cicek Aydin
    Abstract:

    Abstract. A new Microsporidium sp. infects Rhizophagus gran� dis Gyllenhall, a beetle which preys on the bark beetle Den� droctonus micans Kugellan in Turkey. Mature spores are sin-gle, uninucleate, oval in shape (3.75 ± 0.27 µm in length by 2.47 ±  0.13 µm in width),  with a subapically fixed polar filament. The polar filament is anisofilar,  coiled in 7–8 normal and 3–4 re-duced coils. Other characteristic features of the microsporidium are the four/five nuclear divisions to form 16/32 (commonly 16) spores, subpersistent sporophorous vesicles (pansporoblasts) remaining till formation of the endospore, and the vesicles dis-solved with free mature spores. The polaroplast is divided into three zones: an amorphous zone, dense layers, and a lamellar-tubular area extending to the central part of the spore. The beetle Rhizophagus grandis Gyllenhall is an important predator of the bark beetle Dendroctonus micans in Turkey an

  • First record of the insect pathogenic alga Helicosporidium sp. (Chlorophyta: Trebouxiophyceae) infection in larvae and pupae of Rhizophagus grandis Gyll. (Coleoptera, Rhizophaginae) from Turkey
    Journal of invertebrate pathology, 2009
    Co-Authors: Mustafa Yaman, Renate Radek, Onur Tosun, Cicek Aydin, Ömer Ertürk
    Abstract:

    The predator beetle Rhizophagus grandis Gyll. (Coleoptera, Rhizophaginae) is one of the most important biological control agents, mass-bred and used to suppress populations of an important pest: the great spruce bark beetle, Dendroctonus micans. The achlorophyllous alga Helicosporidium sp. was first discovered in the pest. Later it was also found in the predator, but only in the adults. In this study, the pathogenic alga Helicosporidium sp. was discovered in larvae and early pupae of R. grandis for the first time. The morphological characteristics of the pathogenic alga were revealed by light and electron microscopy. Infection rates of Helicosporidium sp. in the larvae and pupae of R. grandis were 23.5% and 6.25%, respectively.

  • identification distribution and occurrence of the ascomycete metschnikowia typographi in the great spruce bark beetle Dendroctonus micans
    Folia Microbiologica, 2008
    Co-Authors: Mustafa Yaman, Renate Radek
    Abstract:

    This is the first report on the ascomycete Metschnikowia typographi from the adults and larvae of the great spruce bark beetle Dendroctonus micans in Turkey. In total, 910 of 1928 adults and 44 of 149 larvae investigated during the two years were infected by the pathogen. In a fresh smear the asci of the pathogen measure 18.5 ± 2.05 μm (14.7–22.3) in length and 2.1 ± 0.4 μm in width (n = 35). The ascospores are about 2 μm shorter than asci, having an average length of 16.4 ± 1.5 μm (14.2–18.0). The total infection rate of D. micans was 47.2 %. The prevalence of M. typographi infections differed between localities and years. Different infection rates of male and female beetles of D. micans were not recognized.

  • helicosporidium infection of the great european spruce bark beetle Dendroctonus micans coleoptera scolytidae
    European Journal of Protistology, 2005
    Co-Authors: Mustafa Yaman, Renate Radek
    Abstract:

    Abstract An infection of the great European spruce bark beetle Dendroctonus micans (from Turkey) by the parasitic green alga Helicosporidium is described. This is the first time that Helicosporidium has been found to infect a bark beetle (Scolytidae) and the first time that a naturally infected beetle has been reported for the Eurasian continent. The typical cysts of Helicosporidium contain three ovoid cells and one helical, filamentous cell. The morphological characteristics are revealed by light and electron microscopy. Distinct electron-dense inclusions with a peculiar ultrastructure may represent pyrenoids. Since D. micans is an important pest, the discovery of a natural pathogen may offer a chance for biological control.

Jean-claude Grégoire - One of the best experts on this subject based on the ideXlab platform.

  • bacterial and fungal symbionts of parasitic Dendroctonus bark beetles
    FEMS Microbiology Ecology, 2016
    Co-Authors: Loic Dohet, Jean-claude Grégoire, Aileen Berasategui, Martin Kaltenpoth, Peter Bphw Biedermann
    Abstract:

    Bark beetles (Curculionidae: Scolytinae) are one of the most species-rich herbivorous insect groups with many shifts in ecology and host-plant use, which may be mediated by their bacterial and fungal symbionts. While symbionts are well studied in economically important, tree-killing species, little is known about parasitic species whose broods develop in living trees. Here, using culture-dependent and independent methods, we provide a comprehensive overview of the associated bacteria, yeasts and filamentous fungi of the parasitic Dendroctonus micans , D. punctatus and D. valens , and compare them to those of other tree-inhabiting insects. Despite inhabiting different geographical regions and/or host trees, the three species showed similar microbial communities. Enterobacteria were the most prevalent bacteria, in particular Rahnella , Pantoea and Ewingella , in addition to Streptomyces . Likewise, the yeasts Candida/Cyberlindnera were the most prominent fungi. All these microorganisms are widespread among tree-inhabiting insects with various ecologies, but their high prevalence overall might indicate a beneficial role such as detoxification of tree defenses, diet supplementation or protection against pathogens. As such, our results enable comparisons of symbiont communities of parasitic bark beetles with those of other beetles, and will contribute to our understanding of how microbial symbioses facilitate dietary shifts in insects.

  • Aligned sequences
    2016
    Co-Authors: François Mayer, Jean-claude Grégoire, Frédéric B. Piel, Anna Cassel-lundhagen, Natalia Kirichenko, Laurent Grumiau, Bjørn Økland, Coralie Bertheau, Patrick Mardulyn
    Abstract:

    Aligned sequences for Ips typographus (COI, EF1a, G6PD, AK, Wg) and for Dendroctonus micans (COI

  • biocontrol of Dendroctonus micans by rhizophagus grandis gyll col rhizophagidae in the massif central france a first appraisal of the mass rearing and release methods
    Journal of Applied Entomology, 2009
    Co-Authors: Jean-claude Grégoire, Joel Merlin, Jacques Pasteels, R Jaffuel, Gerard Vouland, D Schvester
    Abstract:

    Dendroctonus micans, recently arrived in the French Massif Central has reached outbreak level in many spruce stands in the Haute Loire, Ardeche and Lozere, causing important damage. An effort is being made to introduce the specific predator, Rhizophagus grandis, which, in regions where D. micans is endemic, is held to be one of the principal agents that effectively control the pest. Two breeding methods are briefly described, one on spruce logs infested by the prey, the other one in less natural, more controlled conditions. A first medium-scale release of 2,350 predators was made in 1983, subsequent samplings indicatings that they have dispersed and settled. These first results and a survey of the situation of the predator in the region allow a discussion of the strategy for further releases. These latter should preferably be made on the edge of the prey's present range, in situations of incipient infestation and low prey density, so that an area of effective biocontrol could be established to impede the pest's progression from the outbreak region to neighbouring, as yet untouched, stands. There has been a first application of this strategy this year on Mount Aigoual (Lozere and Gard). Resume Dendroctonus micans colonise depuis une vingtaine d'annees les departements de Haute-Loire, d'Ardeche et de Lozere, dans le Massif Central, et y cause d'importants degâts. Des efforts ont ete entrepris depuis quelques annees afin d'introduire dans la region le predateur specifique Rhizophagus grandis qui est considere dans les pays ou D. micans est endemique comme un facteur de regulation de premiere importance. Deux methodes d'elevage du predateur sont decrites, l'une sur des rondins d'epicea infestes par la proie, l'autre dans des conditions moins naturelles mais mieux controlees. Un premier lâcher de moyenne importance a ete realise en 1983 (2.350 insectes). Des echantillonages ulterieurs ont montre que les predateurs se sont correctement etablis. Ces premiers resultats, ainsi que ceux d'un bilan plus general de la situation de Rh. grandis dans la region, permettent la discussion d'une strategie a suivre pour les lâchers suivants. Ceux-ci devront etre effectues de preference sur le front de progression du scolyte, dans des peuplements qui connaissent tout juste un debut d'infestation. De la sorte, une zone de controle effectif pourrait etre etablie et permettrait de freiner la progression du depredateur vers les peuplements indemnes encore en dehors de son aire de distribution. Une premiere application de cette strategie a ete faite cette annee: des lâchers ont ete effectues sur le Mont Aigoual (Depts de Lozere et du Gard). Zusammenfassung Zur biologischen Bekampfung von Dendroctonus micans Kug. (Col., Scolytidae) mit Rhizophagus grandis Gyll. (Col., Rhizophagidae) im franzosischen Centralmassiv: eine erste Bewertung von Massenzucht- und Freilassungsmethoden D. micans, der in jungster Zeit im franzosischen Centralmassiv auftrat, erreichte in Fichtenbestanden von Haute Loire, Ardeche und Lozere so hohe Dichtewerte, das es zu bedeutenden Schaden kam. Es wurden Anstrengungen unternommen, den spezifischen Feind Rh. grandis einzufuhren, der in den endemischen D. micans-Gebieten als einer der Hauptregulatoren des Borkenkafers gilt. Zwei Zuchtmethoden werden kurz beschrieben: eine in Fichtenabschnitten und eine unter weniger naturlichen und mehr kontrollierten Bedingungen. Eine erste Freilassung von 2350 Pradatoren erfolgte 1983, die, wie die Kontrollen zeigten, zur Ansiedlung und Ausbreitung des Pradators fuhrte. Diese ersten Ergebnisse sowie eine Betrachtung der Situation des Pradators im Gebiet erlauben eine Diskussion uber die Strategie weiterer Freilassungen. Solche sollten vorzugsweise am Rande des gegenwartigen Gebietes erfolgen, bei erst beginnendem Befall und noch niedriger Beutedichte, um damit einen Bereich wirksamer Biokontrolle zu schaffen, der einen Schadlingsubergriff auf die noch unbefallenen Nachbarbereiche unterbindet. Eine erste Anwendung dieser Strategie erfolgte im vergangenen Jahr auf dem Mount Aigoual (Lozere und Gard).

  • kairomone traps a tool for monitoring the invasive spruce bark beetle Dendroctonus micans coleoptera scolytinae and its specific predator rhizophagus grandis coleoptera monotomidae
    Journal of Applied Ecology, 2008
    Co-Authors: Nicolas Meurisse, Daniel Couillien, Jean-claude Grégoire
    Abstract:

    Summary 1. The Eurasian spruce bark beetle Dendroctonus micans is a major pest of spruce which is expanding its range in France, Turkey, England and Wales. Its monospecific predator Rhizophagus grandis has followed its prey naturally into most areas and since the 1960s has also been mass-produced and released within newly infested locations. Assessing bark-beetle presence at previously uninfested sites, or predator establishment after release or natural spread, currently depends on direct observation of D. micans brood chambers. This is a slow and unreliable process because bark-beetle attacks are solitary, cryptic and occur on living trees. An effective trapping method would thus be most useful. 2. A synthetic lure for R. grandis was first field-tested in release‐recapture experiments. Release points were surrounded by one or two concentric rings of traps baited with either D. micans larval frass or with a blend of synthetic chemicals. Kairomone-trapping using the synthetic lure was then tested in the field, monitoring R. grandis in 58 spruce stands in Belgium and France. 3. In the release‐recapture experiments, up to 65% of the released predators were caught within 48 h. Catches with the synthetic lure and with prey frass were not significantly different. 4. Field-trapping assays showed R. grandis establishment in 30 stands, including areas where the predator had been introduced artificially. Trapping was unsuccessful at the southern and western limits of D. micans ’ range. Combined visual and trapping approaches identified 32 stands containing the predators, with two false negatives with the trapping method, compared to 19 for the visual surveys. 5. Unexpectedly, male and female D. micans adults were trapped in some cases. The combined approach identified 43 attacked stands, among which there were four false negatives with the trapping method and 11 with the visual surveys. 6. Synthesis and applications. To our knowledge, this is one of the first cases of using kairomone traps to monitor a predator after releases for biocontrol. Furthermore, because this predator is strictly prey-specific, this technique also identifies stands colonized by D. micans bark beetles. Following inoculative predator releases, kairomone trapping could be used to survey for D. micans in areas under colonization or in European Union ‘Protected Zones’.

Grégoire Jean-claude - One of the best experts on this subject based on the ideXlab platform.

  • Bacterial and fungal symbionts of parasitic Dendroctonus bark beetles
    'Oxford University Press (OUP)', 2016
    Co-Authors: Dohet Loïc, Grégoire Jean-claude, Aileen Berasategui, Martin Kaltenpoth, Biedermann, Peter Bphw
    Abstract:

    Bark beetles (Curculionidae: Scolytinae) are one of the most species-rich herbivorous insect groups with many shifts in ecology and host-plant use, which may be mediated by their bacterial and fungal symbionts. While symbionts are well studied in economically important, tree-killing species, little is known about parasitic species whose broods develop in living trees. Here, using culture-dependent and independent methods, we provide a comprehensive overview of the associated bacteria, yeasts and filamentous fungi of the parasitic Dendroctonus micans, D. punctatus and D. valens, and compare them to those of other tree-inhabiting insects. Despite inhabiting different geographical regions and/or host trees, the three species showed similar microbial communities. Enterobacteria were the most prevalent bacteria, in particular Rahnella, Pantoea and Ewingella, in addition to Streptomyces. Likewise, the yeasts Candida/Cyberlindnera were the most prominent fungi. All these microorganisms are widespread among tree-inhabiting insects with various ecologies, but their high prevalence overall might indicate a beneficial role such as detoxification of tree defenses, diet supplementation or protection against pathogens. As such, our results enable comparisons of symbiont communities of parasitic bark beetles with those of other beetles, and will contribute to our understanding of how microbial symbioses facilitate dietary shifts in insects.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

  • haplotype composition for individuals of Dendroctonus micans
    2015
    Co-Authors: Mayer François, Piel, Frédéric B., Cassel-lundhagen Anna, Kirichenko Natalia, Grumiau Laurent, Økland Bjørn, Bertheau Coralie, Grégoire Jean-claude, Mardulyn Patrick
    Abstract:

    haplotype composition for individuals of Dendroctonus micans (Table S20

  • Data from: Comparative multi-locus phylogeography of two Palaearctic spruce bark beetles: influence of contrasting ecological strategies on genetic variation
    2015
    Co-Authors: Mayer François, Piel, Frédéric B., Cassel-lundhagen Anna, Kirichenko Natalia, Grumiau Laurent, Økland Bjørn, Bertheau Coralie, Grégoire Jean-claude, Mardulyn Patrick
    Abstract:

    While phylogeographic patterns of organisms are often interpreted through past environmental disturbances, mediated by climate changes, and geographic barriers, they may also be strongly influenced by species-specific traits. To investigate the impact of such traits, we focused on two Eurasian spruce bark beetles that share a similar geographic distribution, but differ in their ecology and reproduction. Ips typographus is an aggressive tree-killing species characterized by strong dispersal, whereas Dendroctonus micans is a discrete inbreeding species (sib mating is the rule), parasite of living trees and a poor disperser. We compared genetic variation between the two species over both beetles’ entire range in Eurasia with five independent gene fragments, to evaluate whether their intrinsic differences could have an influence over their phylogeographic patterns. We highlighted widely divergent patterns of genetic variation for the two species and argue that the difference is indeed largely compatible with their contrasting dispersal strategies and modes of reproduction. In addition, genetic structure in I. typographus divides European populations in a northern and a southern group, as was previously observed for its host plant, and suggests past allopatric divergence. A long divergence time was estimated between East Asian and other populations of both species, indicating their long-standing presence in Eurasia, prior to the last glacial maximum. Finally, the strong population structure observed in D. micans for the mitochondrial locus provides insights into the recent colonization history of this species, from its native European range to regions where it was recently introduced

  • Comparative multi-locus phylogeography of two Palaearctic spruce bark beetles: influence of contrasting ecological strategies on genetic variation
    'Wiley', 2015
    Co-Authors: Mayer François, Cassel-lundhagen Anna, Kirichenko Natalia, Grumiau Laurent, Bertheau Coralie, Grégoire Jean-claude, Piel Frédéric, Mardulyn Patrick
    Abstract:

    International audienceWhile phylogeographic patterns of organisms are often interpreted through past environmental disturbances, mediated by climate changes, and geographic barriers, they may also be strongly influenced by species-specific traits. To investigate the impact of such traits, we focused on two Eurasian spruce bark beetles that share a similar geographic distribution, but differ in their ecology and reproduction. Ips typographus is an aggressive tree-killing species characterized by strong dispersal, whereas Dendroctonus micans is a discrete inbreeding species (sib mating is the rule), parasite of living trees and a poor disperser. We compared genetic variation between the two species over both beetles’ entire range in Eurasia with five independent gene fragments, to evaluate whether their intrinsic differences could have an influence over their phylogeographic patterns. We highlighted widely divergent patterns of genetic variation for the two species and argue that the difference is indeed largely compatible with their contrasting dispersal strategies and modes of reproduction. In addition, genetic structure in I. typographus divides European populations in a northern and a southern group, as was previously observed for its host plant, and suggests past allopatric divergence. A long divergence time was estimated between East Asian and other populations of both species, indicating their long-standing presence in Eurasia, prior to the last glacial maximum. Finally, the strong population structure observed in D. micans for the mitochondrial locus provides insights into the recent colonization history of this species, from its native European range to regions where it was recently introduced

  • Comparative multi-locus phylogeography of two Palaearctic spruce bark beetles: influence of contrasting ecological strategies on genetic variation.
    'Wiley', 2015
    Co-Authors: Mayer François, Cassel-lundhagen Anna, Kirichenko Natalia, Grumiau Laurent, Økland Bjørn, Bertheau Coralie, Grégoire Jean-claude, Piel Frédéric, Mardulyn Patrick
    Abstract:

    While phylogeographic patterns of organisms are often interpreted through past environmental disturbances, mediated by climate changes, and geographic barriers, they may also be strongly influenced by species-specific traits. To investigate the impact of such traits, we focused on two Eurasian spruce bark beetles that share a similar geographical distribution, but differ in their ecology and reproduction. Ips typographus is an aggressive tree-killing species characterized by strong dispersal, whereas Dendroctonus micans is a discrete inbreeding species (sib-mating is the rule), parasite of living trees and a poor disperser. We compared genetic variation between the two species over both beetles' entire range in Eurasia with five independent gene fragments, to evaluate whether their intrinsic differences could have an influence over their phylogeographic patterns. We highlighted widely divergent patterns of genetic variation for the two species, and argue that the difference is indeed largely compatible with their contrasting dispersal strategies and modes of reproduction. In addition, genetic structure in I. typographus divides European populations in a northern and a southern group, as was previously observed for its host plant, and suggests past allopatric divergence. A long divergence time was estimated between East Asian and other populations of both species, indicating their long-standing presence in Eurasia, prior to the last glacial maximum. Finally, the strong population structure observed in D. micans for the mitochondrial locus provides insights into the recent colonization history of this species, from its native European range to regions where it was recently introduced. This article is protected by copyright. All rights reserved.SCOPUS: re.jFLWINinfo:eu-repo/semantics/publishe

Voisin Paul - One of the best experts on this subject based on the ideXlab platform.