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Jan Hubert - One of the best experts on this subject based on the ideXlab platform.

  • differences in the bacterial community of laboratory and wild populations of the predatory mite Cheyletus eruditus acarina cheyletidae and bacteria transmission from its prey acarus siro acari acaridae
    Journal of Economic Entomology, 2016
    Co-Authors: Jan Hubert, Radek Aulický, Václav Stejskal, Jan Kopecky, Marta Nesvorna, Tomas Erban
    Abstract:

    The parthenogenetic predatory mite Cheyletus eruditus (Schrank, 1781) is used for biological control against mite pests produced as CHEYLETIN. Although there is evidence that bacteria are mainly responsible for parthenogeny in several species of predatory mites, the description of association between C. eruditus the specific and parasitic or symbiotic bacteria is still missing. We analyzed the bacterial communities of the predator, C. eruditus , and its prey, Acarus siro L. The 16S rRNA gene was amplified, cloned, and sequenced. The selected bacterial taxa were confirmed by amplification of isolated DNA with taxon-specific primers. The 16S rRNA gene sequences from the predatory and prey mites formed a total of 20 different bacterial taxa. Of these taxa, the predator and prey shared four taxa, six taxa were specific for the predatory, and 10 taxa for the prey mites. Cardinium - and Bartonella -like bacteria were found in both mite species. The reproductive parasite Wolbachia was found only in the predatory mite, and A. siro hosted Solitalea -like (Sphingobacteriales) bacteria that were not detected in C. eruditus . We focused on Cardinium occurrence in the field samples of C. eruditus. Using Cardinium -specific primers, 128 clones were obtained. Cardinium was found in seven field samples of C. eruditus as well as in the laboratory population that was used to produce CHEYLETIN. Phylogenetic analysis of the Cardinium clones identified three separate clusters: two clusters showed high similarity to the Cardinium sequences from astigmatid mites, and one cluster contained only the clones from C. eruditus . Sequences of both Cardinium and Wolbachia were found in the both adults and eggs of C. eruditus , indicating maternal transfer of these endosymbiotic bacteria.

  • prey range of the predatory mite Cheyletus malaccensis acari cheyletidae and its efficacy in the control of seven stored product pests
    Biological Control, 2009
    Co-Authors: Ruth Cebolla, Stanislav Pekar, Jan Hubert
    Abstract:

    Abstract The prey range of the predatory mite Cheyletus malaccensis was evaluated on the basis of its population growth on various prey species under laboratory conditions. The prey species were selected from pest species syntopically occurring in stored grain habitats in central Europe. The laboratory experiments were carried out in vials containing 100 g of wheat grain and either 100 individuals of a mite pest species (Acarus siro, Aleuroglyphus ovatus, Caloglyphus redickorzevi, Lepidoglyphus destructor or Tyrophagus putrescentiae) or 50 eggs of an insect pest species (Tribolium castaneum or Ephestia kuehniella). The predatory mites were introduced at four predator-to-prey ratios: 0, 0.02, 0.04, and 0.1. The vials were maintained under optimal conditions for the pest species’ development (15% m.c. and 25 °C), and the pest and predator densities were checked after 21 days. C. malaccensis consumed all five mite species and some eggs of T. castaneum, but not eggs of E. kuehniella, suggesting a strictly acarophagous predatory habit. At low initial predator/prey ratios, the population of C. malaccensis increased most on diets of C. redickorzevi, A. ovatus or L. destructor, and less on diets of A. siro or T. putrescentiae. The highest control efficacy was achieved on A. ovatus and L. destructor. Thus, we conclude that C. malaccensis is an oligophagous predator of Acari and should be used in the control of mite pest species, particularly A. ovatus and L. destructor.

  • combination of the antifeedant bean flour and the predator Cheyletus malaccensis suppresses storage mites under laboratory conditions
    Biocontrol, 2009
    Co-Authors: Jan Hubert, Stanislav Pekar
    Abstract:

    Stored product mites are pests of serious economic and medical importance. Recently, it has been shown that the biological control of these pests based on the use of natural compounds and predators had a high potential for success. In this study, we investigated the suppression of three pest mites by combination of the predator Cheyletus malaccensis Oudemans, 1913 and bean flour (Phaseolus vulgaris), which is an antifeedant. Wheat grain (100 g) was contaminated with 100 individuals (Acarus siro (Linnaeus, 1758), Aleuroglyphus ovatus (Troupeau, 1878) or Tyrophagus putrescentiae (Schrank, 1781)). We added bean flour in concentrations of 0, 1, 5 and 10 g kg−1 (wt/wt) and/or the predator with initial predator/prey ratios 0, 1/50, 1/25 and 1/10. The experiment was carried out under abiotic conditions that are optimal for pest development. After 21 days, pest and predators numbers were recorded. Application of flour significantly reduced populations of A. siro, slightly reduced populations of T. putrescentiae, the efficiency increased with increasing concentration. A. ovatus was not affect by bean flour. Populations of all mite species were successfully reduced by the sole addition of C. malaccensis, with a higher efficiency at higher Cheyletus ratios. The additive effect of the predator and flour was mainly apparent in the reduction of T. putrescientae. The population of C. malaccensis was not affected by the presence of bean flour. It is therefore recommended to use bean flour for the reduction of A. siro, a combination of bean flour and Cheyletus for the reduction of T. putrescientae, and only Cheyletus for the reduction of A. ovatus.

  • assessing biological control of acarus siro by Cheyletus malaccensis under laboratory conditions effect of temperatures and prey density
    Journal of Stored Products Research, 2008
    Co-Authors: Stanislav Pekar, Jan Hubert
    Abstract:

    Abstract In stored grain, the predatory mite Cheyletus spp. may be used to control the pest mite Acarus siro . The efficiency of control depends on many factors, particularly ambient temperature. In this study we investigated the effects of temperature and initial prey density on the prey–predator system under laboratory conditions. Ratio–response models were fitted to estimate the efficiency of control for three temperatures. At 15 °C a 90% reduction of A. siro was achieved by releasing nine Cheyletus malaccensis individuals into a population of 100 A. siro individuals in 1 kg of grain. At 20 °C, 90% reduction required seven C. malaccensis individuals and at 25 °C, it required three C. malaccensis individuals. Without the predator the intrinsic rates of increase of A. siro populations increased with temperature and were highest for an initial density of 100 individuals, revealing some form of positive interaction among A. siro individuals during food processing. The intrinsic rates of increase of C. malaccensis populations also increased with temperature and decreased with increasing density of the predator, presumably as a result of interference competition among predators. At 15 °C the rate of increase for A. siro was higher than that for C. malaccensis, while at higher temperatures it was the other way around. Lower developmental thresholds were 10 °C for A. siro and 13.6 °C for C. malaccensis . In order to find when an artificial release of C. malaccensis is most efficient we simulated a population increase of A. siro using temperature records from one grain store. In Central Europe this type of biological control can be efficient only when the predator is released at the beginning of storage, i.e. in September and October.

  • combined effect of an antifeedant amylase inhibitor and a predator Cheyletus malaccensis in controlling the stored product mite acarus siro
    Physiological Entomology, 2007
    Co-Authors: Jan Hubert, Jana Hýblova, Ivana Křižkovakudlikova, Lucie Doleckovamaresova, Stanislav Pekar, Zuzana Munzbergova, Václav Stejskal, Marek Mares
    Abstract:

    Acarus siro is the most abundant and frequent mite to infest stored-food products, causing allergies and transmitting mycotoxin producing fungi. The predatory mite Cheyletus malaccensis is a candidate species in the biocontrol programme for this pest. In vitro, the a-amylase inhibitor acarbose is effective against the a-amylase of A. siro but not against that of C. malaccensis. In vivo, the impact of acarbose on a population of A. siro is investigated along with the interaction with the predator. Various densities of adult parthenogenetic females of C. malaccensis are reared on A. siro feeding on either a control diet or a diet containing different acarbose concentrations. The combined action of both factors significantly improved the final biocontrol efficiency with C. malaccensis, compensating for the lower energetic content of the prey on acarbose by increasing the number of prey caught.

Lareschi Marcela - One of the best experts on this subject based on the ideXlab platform.

  • First report of ectoparasites associated with Red Bellied Squirrel Callosciurus erythraeus (Rodentia: Sciuridae) introduced into Argentina
    'Wiley', 2013
    Co-Authors: Gozzi A. C., Guichon M. L., Benitez V., Lareschi Marcela
    Abstract:

    Introduced species usually modify parasite-host dynamics by bringing new parasites or by acquiring local parasites. The loss of parasites may determine the outcome of invasions, if introduced species are liberated from their coevolved parasites in the invaded range. Also, introduced species may pose sanitary risks to humans and other mammals, if they are reservoir of pathogens or carry arthropod vectors. The red-bellied squirrel, Callosciurus erythraeus (Pallas) (Rodentia: Sciuridae), was introduced into Argentina in 1970 and since then, several foci of invasion appeared closely associated with humans. Parasitological fauna of C. erythraeus in Argentina will inform about novel parasite-host dynamics and may provide new insight into their invasion success. The objective of this study was to describe the arthropod parasites of C. erythraeus in Argentina in comparison with previous studies conducted in native and introduced ranges. Occasional host-parasite associations with local arthropod parasites not previously described for C. erythraeus are reported: the mites Androlaelaps fahrenholzi (Ewing) (Parasitiformes: Laelapidae) and Ornithonyssus cf. bacoti (Parasitiformes: Macronyssidae), the flea Polygenis (Polygenis) rimatus Jordan (Siphonaptera: Rhopalopsyllidae) and the botfly Cuterebra Clark (Diptera: Oestridae: Cuterebrinae). Cheyletus sp. mites (Acariformes: Cheyletidae) were also found. Low prevalence and mean intensity of ectoparasite species could influence invasion dynamics.Fil: Gozzi, A. C.. Universidad Nacional de Luján; ArgentinaFil: Guichon, M. L.. Universidad Nacional de Luján; ArgentinaFil: Benitez, V. V.. Universidad Nacional de Luján; ArgentinaFil: Lareschi, Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Estudios Parasitológicos y de Vectores (i); Argentina. Universidad Nacional de La Plata; Argentin

  • Arthropod parasites of the red-bellied squirrel Callosciurus erythraeus (Rodentia: Sciuridae) introduced into Argentina
    'Wiley', 2013
    Co-Authors: Gozzi A. C., Guichon, Maria Laura, Benitez, Verónica Victoria, Lareschi Marcela
    Abstract:

    The introduction of an exotic species usually modifies parasite–host dynamics by the import of new parasites or the exotic species' acquiral of local parasites. The loss of parasites may determine the outcome of an invasion if the introduced species is liberated from co-evolved parasites in its range of invasion. In addition, an introduced species may pose sanitary risks to humans and other mammals if it serves as a reservoir of pathogens or carries arthropod vectors. The red-bellied squirrel, Callosciurus erythraeus (Pallas) (Rodentia: Sciuridae), was introduced into Argentina in 1970, since when several foci of invasion have been closely associated with humans. Investigation of the parasitological fauna of C. erythraeus in Argentina will generate new information about novel parasite–host dynamics and may provide new insight into the reasons for the successful invasion of this species. The objective of this study was to describe the arthropod parasites of C. erythraeus in Argentina in comparison with previous studies of parasites of this species in its native habitat and in the ranges of its invasion. Occasional host–parasite associations with local arthropod parasites not previously described for C. erythraeus are reported; these include the mites Androlaelaps fahrenholzi (Ewing) (Mesostigmata: Laelapidae) and Ornithonyssus cf. bacoti (Mesostigmata: Macronyssidae), the flea Polygenis (Polygenis) rimatus Jordan (Siphonaptera: Rhopalopsyllidae) and the botfly Cuterebra Clark (Diptera: Oestridae: Cuterebrinae). Cheyletus sp. mites (Trombidiformes: Cheyletidae) were also found. The low prevalence and mean intensity of ectoparasite species may influence invasion dynamics.Fil: Gozzi, A. C.. Universidad Nacional de Luján. Departamento de Ciencias Básicas; ArgentinaFil: Guichon, Maria Laura. Universidad Nacional de Luján. Departamento de Ciencias Básicas; ArgentinaFil: Benitez, Verónica Victoria. Universidad Nacional de Luján. Departamento de Ciencias Básicas; ArgentinaFil: Lareschi, Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico La Plata. Centro de Estudios Parasitológicos y de Vectores (i); Argentin

Stanislav Pekar - One of the best experts on this subject based on the ideXlab platform.

  • prey range of the predatory mite Cheyletus malaccensis acari cheyletidae and its efficacy in the control of seven stored product pests
    Biological Control, 2009
    Co-Authors: Ruth Cebolla, Stanislav Pekar, Jan Hubert
    Abstract:

    Abstract The prey range of the predatory mite Cheyletus malaccensis was evaluated on the basis of its population growth on various prey species under laboratory conditions. The prey species were selected from pest species syntopically occurring in stored grain habitats in central Europe. The laboratory experiments were carried out in vials containing 100 g of wheat grain and either 100 individuals of a mite pest species (Acarus siro, Aleuroglyphus ovatus, Caloglyphus redickorzevi, Lepidoglyphus destructor or Tyrophagus putrescentiae) or 50 eggs of an insect pest species (Tribolium castaneum or Ephestia kuehniella). The predatory mites were introduced at four predator-to-prey ratios: 0, 0.02, 0.04, and 0.1. The vials were maintained under optimal conditions for the pest species’ development (15% m.c. and 25 °C), and the pest and predator densities were checked after 21 days. C. malaccensis consumed all five mite species and some eggs of T. castaneum, but not eggs of E. kuehniella, suggesting a strictly acarophagous predatory habit. At low initial predator/prey ratios, the population of C. malaccensis increased most on diets of C. redickorzevi, A. ovatus or L. destructor, and less on diets of A. siro or T. putrescentiae. The highest control efficacy was achieved on A. ovatus and L. destructor. Thus, we conclude that C. malaccensis is an oligophagous predator of Acari and should be used in the control of mite pest species, particularly A. ovatus and L. destructor.

  • combination of the antifeedant bean flour and the predator Cheyletus malaccensis suppresses storage mites under laboratory conditions
    Biocontrol, 2009
    Co-Authors: Jan Hubert, Stanislav Pekar
    Abstract:

    Stored product mites are pests of serious economic and medical importance. Recently, it has been shown that the biological control of these pests based on the use of natural compounds and predators had a high potential for success. In this study, we investigated the suppression of three pest mites by combination of the predator Cheyletus malaccensis Oudemans, 1913 and bean flour (Phaseolus vulgaris), which is an antifeedant. Wheat grain (100 g) was contaminated with 100 individuals (Acarus siro (Linnaeus, 1758), Aleuroglyphus ovatus (Troupeau, 1878) or Tyrophagus putrescentiae (Schrank, 1781)). We added bean flour in concentrations of 0, 1, 5 and 10 g kg−1 (wt/wt) and/or the predator with initial predator/prey ratios 0, 1/50, 1/25 and 1/10. The experiment was carried out under abiotic conditions that are optimal for pest development. After 21 days, pest and predators numbers were recorded. Application of flour significantly reduced populations of A. siro, slightly reduced populations of T. putrescentiae, the efficiency increased with increasing concentration. A. ovatus was not affect by bean flour. Populations of all mite species were successfully reduced by the sole addition of C. malaccensis, with a higher efficiency at higher Cheyletus ratios. The additive effect of the predator and flour was mainly apparent in the reduction of T. putrescientae. The population of C. malaccensis was not affected by the presence of bean flour. It is therefore recommended to use bean flour for the reduction of A. siro, a combination of bean flour and Cheyletus for the reduction of T. putrescientae, and only Cheyletus for the reduction of A. ovatus.

  • assessing biological control of acarus siro by Cheyletus malaccensis under laboratory conditions effect of temperatures and prey density
    Journal of Stored Products Research, 2008
    Co-Authors: Stanislav Pekar, Jan Hubert
    Abstract:

    Abstract In stored grain, the predatory mite Cheyletus spp. may be used to control the pest mite Acarus siro . The efficiency of control depends on many factors, particularly ambient temperature. In this study we investigated the effects of temperature and initial prey density on the prey–predator system under laboratory conditions. Ratio–response models were fitted to estimate the efficiency of control for three temperatures. At 15 °C a 90% reduction of A. siro was achieved by releasing nine Cheyletus malaccensis individuals into a population of 100 A. siro individuals in 1 kg of grain. At 20 °C, 90% reduction required seven C. malaccensis individuals and at 25 °C, it required three C. malaccensis individuals. Without the predator the intrinsic rates of increase of A. siro populations increased with temperature and were highest for an initial density of 100 individuals, revealing some form of positive interaction among A. siro individuals during food processing. The intrinsic rates of increase of C. malaccensis populations also increased with temperature and decreased with increasing density of the predator, presumably as a result of interference competition among predators. At 15 °C the rate of increase for A. siro was higher than that for C. malaccensis, while at higher temperatures it was the other way around. Lower developmental thresholds were 10 °C for A. siro and 13.6 °C for C. malaccensis . In order to find when an artificial release of C. malaccensis is most efficient we simulated a population increase of A. siro using temperature records from one grain store. In Central Europe this type of biological control can be efficient only when the predator is released at the beginning of storage, i.e. in September and October.

  • combined effect of an antifeedant amylase inhibitor and a predator Cheyletus malaccensis in controlling the stored product mite acarus siro
    Physiological Entomology, 2007
    Co-Authors: Jan Hubert, Jana Hýblova, Ivana Křižkovakudlikova, Lucie Doleckovamaresova, Stanislav Pekar, Zuzana Munzbergova, Václav Stejskal, Marek Mares
    Abstract:

    Acarus siro is the most abundant and frequent mite to infest stored-food products, causing allergies and transmitting mycotoxin producing fungi. The predatory mite Cheyletus malaccensis is a candidate species in the biocontrol programme for this pest. In vitro, the a-amylase inhibitor acarbose is effective against the a-amylase of A. siro but not against that of C. malaccensis. In vivo, the impact of acarbose on a population of A. siro is investigated along with the interaction with the predator. Various densities of adult parthenogenetic females of C. malaccensis are reared on A. siro feeding on either a control diet or a diet containing different acarbose concentrations. The combined action of both factors significantly improved the final biocontrol efficiency with C. malaccensis, compensating for the lower energetic content of the prey on acarbose by increasing the number of prey caught.

Eva Žďárková - One of the best experts on this subject based on the ideXlab platform.

  • A model of the biological control of Acarus siro by Cheyletus eruditus (Acari: Acaridae, Cheyletidae) on grain
    Journal of Pest Science, 2004
    Co-Authors: Stano Pekár, Eva Žďárková
    Abstract:

    The aim of the study was to develop a stage-structured within-patch model describing predator-prey interactions of Cheyletus eruditus (Schrank) and Acarus siro L. on stored grain. Parameterisation of the model was done using data from the literature. Due to considerable variance in these data, statistical methods were used to extrapolate the parameters. The results of the simulations were compared with the experimental control of A. siro by C. eruditus on wheat. The results indicated that all life-history studies of A. siro yielded overestimated parameters leading to an unnaturally rapid population growth of A. siro on grain. The main reason seems to be the use of high quality food (wheat germs), which considerably increased fecundity. A new model with reduced fecundity was found to correspond well with the observed dynamics in a granary. The model of C. eruditus , including parameters from different sources, produced dynamics quite similar to the observed one. A simulation of biological control under laboratory conditions, on 45 g of wheat, showed that C. eruditus is able to control A. siro within the observed period. In contrast, simulation of the control in a granary showed a marked difference in comparison with the observed dynamics. The discrepancy is attributed to the effects of spatial factors, such as immigration. The predator-prey model developed here appears to be valid for the prediction of the local (within-patch) population dynamics of A. siro and C. eruditus on wheat grain at 20 °C and 80% RH.

  • Biological Control of Storage Mites by Cheyletus Eruditus
    Integrated Pest Management Reviews, 1998
    Co-Authors: Eva Žďárková
    Abstract:

    A history of the biological control of stored product mites is reviewed. Thirty-five references in the scientific literature were found principally dealing with acarine predators. The first paper to point out the specific value of Cheyletus eruditus as a predator of acaroid mites appeared in 1912. In 1965 biological control utilizing C. eruditus was put into practice for the first time and in 1986 a method of mass rearing the predator was developed.

Lise Roy - One of the best experts on this subject based on the ideXlab platform.

  • no deleterious effect of inundative releases of biological agents on native arthropod assemblages in poultry farms a mesocosm experiment
    Biological Control, 2021
    Co-Authors: Ghais Zriki, Rumsais Blatrix, Liza Dadu, Annesophie Soulie, Jordan Dijoux, David Degueldre, Nathalie Sleeckx, Lise Roy
    Abstract:

    Abstract Augmentative biological control relies on the inundative release of natural enemies of pests that are usually mass-reared in the laboratory. This practice substantially reduces the environmental impact of pest control in agriculture by reducing the use of insecticides. However, there are many reasons to expect more or less deleterious effects on biodiversity: if the enemy is not specific to the pest, the release of large populations of predators can directly affect native assemblages through the predation process itself and/or through competition with their native counterparts. In addition, mass-reared populations of enemies generally come from gene pools that are different from native populations and may, through the effects of hybridization, alter their population dynamics. On the other hand, during mass rearing, populations of natural enemies to be released are subject to different selection pressures from those in the field and may be less adapted than native populations to farm ecosystems. These effects are generally very difficult to assess in agro-ecosystems themselves due to the multiplicity of factors. In order to assess the effects of inundative releases of generalist predatory mites on native assemblages that colonize poultry houses from the surrounding environment, we conducted an experiment over several generations of mites using mesocosms mimicking a piece of a henhouse (mite-proof units, each housing one hen). No deleterious effects on native populations of Androlaelaps casalis and Cheyletus spp. have been detected from the mass introduction of marketed populations of A. casalis and C. eruditus. The mass introduction of marketed predatory mites against D. gallinae appears to be compatible with the conservation of native arthropod assemblages. The mass-reared populations of A. casalis and C. eruditus did not establish their populations under conditions which otherwise allowed their native counterparts (same taxa) to do so.

  • predation interactions among henhouse dwelling arthropods with a focus on the poultry red mite dermanyssus gallinae
    Pest Management Science, 2020
    Co-Authors: Ghais Zriki, Rumsais Blatrix, Lise Roy
    Abstract:

    BACKGROUND Analysis of the poorly explored food webs of henhouse-dwelling arthropods would improve biological control against the poultry red mite (PRM) Dermanyssus gallinae (De Geer). This study aimed to identify trophic links among native predatory arthropods, PRM, and alternative preys. In vitro predation tests were carried out to assess (i) the ability of native predators to feed on PRM juvenile and adult stages in two physiological statuses (unfed and freshly blood-fed) in the absence of any physical barrier, (ii) predator preferences between PRM and astigmatic mites, and (iii) predation interactions between PRM predators. RESULTS Ten arthropod taxa fed on PRM with predation rates ranging from 4% to 95% in our experimental conditions. They belonged to (i) Acari: Androlaelaps casalis (Berlese), Cheyletus spp., Macrocheles muscaedomesticae (Scopoli), M. penicilliger (Berlese), Parasitus fimetorum (Berlese), Dendrolaelaps spp. and Uroobovella fimicola (Berlese); (ii) other Arachnida: Lamprochernes nodosus (Schrank) (Pseudoscorpionida) and a linyphiid spider; and (iii) Insecta: Lyctocoris campestris (Fabricius). These predators varied in their preference for PRM stages and physiological statuses (unfed or freshly blood-fed). When given a choice, most predators preferred to feed on PRM than astigmatic mites. Bidirectional predation occurred within two pairs of PRM predators (M. penicilliger-Lamprochernes nodosus and A. casalis-Cheyletus spp.), and M. penicilliger had a 100% predation rate on A. casalis. CONCLUSION Our study highlights the potential of various arthropod predators occurring naturally in poultry houses for conservation and augmentative biological control of PRM. Predation interactions between these predators should be accounted for before developing biocontrol agents against PRM. © 2020 Society of Chemical Industry.