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Harry K. Kaya - One of the best experts on this subject based on the ideXlab platform.
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food preference of sancassania polyphyllae acari acaridae living entomopathogenic nematodes or insect tissues
Biocontrol Science and Technology, 2010Co-Authors: Zeynep Ipek Ekmen, Mehmet Karagoz, Nurdan Ozer, Selcuk Hazir, Ibrahim Cakmak, Harry K. KayaAbstract:Abstract Sancassania polyphyllae (Acari: Acaridae) adult female mites will feed on insect cadavers and infective juveniles (IJs) of entomopathogenic nematodes. Our objective was to determine whether S. polyphyllae has a food preference when offered a choice between tissues of Polyphylla fullo (Coleoptera: Scarabaeidae) or Galleria mellonella (Lepidoptera: Pyralidae), or IJs of Steinernema feltiae (Rhabditida: Steinernematidae) or IJs of Heterorhabditis bacteriophora (Rhabditida: Heterorhabditidae). When offered a choice between no food and one of the different food sources, P. fullo, G. mellonella or S. feltiae IJs, S. polyphyllae had a significant preference for food sources compared to no food. When it was offered either no food or H. bacteriophora, there was no significant difference in the mite distribution. When offered two different food choices, P. fullo or G. mellonella, P. fullo or S. feltiae, and P. fullo or H. bacteriophora, the mite showed significant preferences for P. fullo larvae. In S. fel...
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entomopathogenic nematodes steinernematidae and Heterorhabditidae for biological control of soil pests
Turkish Journal of Biology, 2003Co-Authors: Selcuk Hazir, Harry K. Kaya, Patricia S Stock, Nevin KeskinAbstract:Several species of entomopathogenic nematodes in the families Steinernematidae (Steinernema) and Heterorhabditidae (Heterorhabditis) are being produced commercially and used as biological control agents against many soil insect pests and insects in cryptic habitats in many parts of the world. These nematodes, which are mutualistically associated with bacteria (Steinernema with Xenorhabdus bacteria and Heterorhabditis with Photorhabdus bacteria), offer a number of advantages because they have a broad host range, kill their hosts within 48 h, can be easily produced in vivo and in vitro, can be applied with standard spray equipment, are safe to humans and other non-target organisms, have no known negative effects on the environment, and do not require registration in many countries. We present a general overview on the current state of knowledge of entomopathogenic nematodes and their mutualistically associated bacteria. In addition, we examine the potential of these nematodes, which are commonly found in Turkish soils, as biological control agents against insect pests in Turkey.
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diversity and distribution of entomopathogenic nematodes rhabditida steinernematidae and Heterorhabditidae in turkey
Biodiversity and Conservation, 2003Co-Authors: Selcuk Hazir, Harry K. Kaya, Patricia S Stock, Nevin Keskin, Servet OzcanAbstract:The diversity and distribution of entomopathogenic nematodes in thefamilies Steinernematidae and Heterorhabditidae were assessed throughout anextensive soil survey in Turkey during 1999 and 2000. Entomopathogenic nematodeswere recovered from six out of seven regions sampled, with 22 positive sites(2%) out of 1080 sites sampled. A single nematode isolate was recovered at eachof the positive sites, of which 15 were steinernematid isolates and seven wereheterorhabditid isolates representing a total of four species. Based onmorphometric and molecular data, the nematode species were identified asHeterorhabditis bacteriophora, Steinernemafeltiae, S. affine, andSteinernema n. sp. The most common species was S.feltiae, which was isolated from 10 sites in six regions, followed byH. bacteriophora from seven sites in five regions,S. affine from four sites in two regions, andSteinernema n. sp. from one site. Heterorhabditisbacteriophora and S. feltiae have been found inmany parts of the world, whereas S. affine, so far, hasonly been recovered in Europe until our survey. Steinernemaaffine was isolated from the European (Marmara) as well as theAsiatic region (Middle Anatolia) of Turkey. A new undescribedSteinernema sp. was isolated from the most eastern region(East Anatolia) of Turkey. Soils of the positive sites were classified as sandy,sandy loam, or loam (68.2%) and sandy–clay–loam or clay loam (31.8%) and the pHranged from 5.6 to 7.9. The habitats from which the entomopathogenic nematodeswere isolated were broadly classified as disturbed (59.1%), which includedagricultural fields and poplar planted for lumber and wind breaks, andundisturbed (40.9%), which included pine forest, grassland, marsh and reed sites.Steinernema feltiae, S. affine, andH. bacteriophora were recovered from both disturbed andundisturbed habitats. The new Steinernema sp. was recoveredfrom grassland. Our survey showed that these nematodes occur widely throughoutTurkey, but at a frequency below that reported for other parts of the world.
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variation in entomopathogenic nematode steinernematidae and Heterorhabditidae infective stage jumping behaviour
Nematology, 2002Co-Authors: James F Campbell, Harry K. KayaAbstract:Species and strains of entomopathogenic nematodes (Heterorhabditidae and Steinernematidae) were assessed for the expression of standing and jumping behaviour. Jumping occurred in 11 species of Steinernema, but the rate of jumping varied considerably among the species. Variation in the duration of crawling bouts, the tendency to body wave, the rate of standing, the duration of standing bouts, and the tendency to jump after standing contributed to the differences in frequency of jumping among species. Within a species, nematodes that jumped were similar in size, infectivity and sex ratio to those that did not jump, but jumpers tended to be more infective and to have lost their sheath (i.e., the second stage cuticle). This comparison of species is an important first step in assessing the adaptive value of jumping behaviour as part of the foraging strategies of entomopathogenic nematodes.
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Distribution of entomopathogenic nematodes (Steinernematidae and Heterorhabditidae) in natural habitats in California, USA
Biodiversity & Conservation, 1999Co-Authors: S. Patricia Stock, Barry M. Pryor, Harry K. KayaAbstract:A total of 270 soil samples from 30 different habitats in 10 geographic regions of California were evaluated for the presence of rhabditid entomopathogenic nematodes. Nematodes were isolated from 26.3% of the samples. The recovered isolates were identified as Steinernema carpocapsae, S. feltiae, S. kraussei, S. longicaudum, S. oregonense, Heterorhabditis marelatus and H.bacteriophora. Among the steinernematids, S. kraussei and S. feltiae were the most commonly encountered species, generally occurring in acidic soils high in organic matter. Among the heterorhabditids, H. bacteriophora was isolated along the southern coast, whereas H. marelatus was recovered along the northern coast of California. Steinernematids were recovered from coniferous forests, oak woodlands and grasslands whereas heterorhabditids were isolated from coastal marshes.
Selcuk Hazir - One of the best experts on this subject based on the ideXlab platform.
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food preference of sancassania polyphyllae acari acaridae living entomopathogenic nematodes or insect tissues
Biocontrol Science and Technology, 2010Co-Authors: Zeynep Ipek Ekmen, Mehmet Karagoz, Nurdan Ozer, Selcuk Hazir, Ibrahim Cakmak, Harry K. KayaAbstract:Abstract Sancassania polyphyllae (Acari: Acaridae) adult female mites will feed on insect cadavers and infective juveniles (IJs) of entomopathogenic nematodes. Our objective was to determine whether S. polyphyllae has a food preference when offered a choice between tissues of Polyphylla fullo (Coleoptera: Scarabaeidae) or Galleria mellonella (Lepidoptera: Pyralidae), or IJs of Steinernema feltiae (Rhabditida: Steinernematidae) or IJs of Heterorhabditis bacteriophora (Rhabditida: Heterorhabditidae). When offered a choice between no food and one of the different food sources, P. fullo, G. mellonella or S. feltiae IJs, S. polyphyllae had a significant preference for food sources compared to no food. When it was offered either no food or H. bacteriophora, there was no significant difference in the mite distribution. When offered two different food choices, P. fullo or G. mellonella, P. fullo or S. feltiae, and P. fullo or H. bacteriophora, the mite showed significant preferences for P. fullo larvae. In S. fel...
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diversity and distribution of entomopathogenic nematodes steinernematidae Heterorhabditidae in south africa
Journal of Invertebrate Pathology, 2009Co-Authors: Justin Hatting, Patricia S Stock, Selcuk HazirAbstract:A total of 1506 soil samples from different habitats in seven geographic regions of South Africa were evaluated for the presence of entomopathogenic nematodes (EPN). Nematodes were isolated from 5% of the samples. Among the steinernematids, four Steinernema sp. were recovered including Steinernema khoisanae and three new undescribed species. Although steinernematids were recovered from both humid subtropical and semiarid regions, this family accounted for 80% of EPN recovered from the semiarid climate zones characterised by sandy, acidic soils. Eight isolates of S. khoisanae were recovered from the Western Cape province. One of the new undescribed steinernematids (Steinernema sp. 1) was recovered only from the Free State and KwaZulu-Natal provinces where humid subtropical conditions prevail and soils are generally less acidic with higher clay content. A high level of adaptation, however, was noted with Steinernema sp. 2, which was recovered from a wide range of soil conditions and habitats ranging from semiarid (Western Cape province) to humid subtropical (KwaZulu-Natal province). A third undescribed steinernematid, Steinernema sp. 3, seemed better adapted to heavier soils with more than 80% of isolates recovered from fruit orchards in the Free State province. Heterorhabditis bacteriophora was the only heterorhabditid recovered during this survey. This species was particularly prevalent in four provinces ranging from humid subtropical to semiarid regions. Isolation of EPN directly from insect cadavers included Steinernema sp. 2 and one H. bacteriophora from an unidentified white grub (Scarabaeidae) cadaver (i.e., dual infection) and H. bacteriophora from the black vine weevil, Otiorhynchus sulcatus.
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entomopathogenic nematodes steinernematidae and Heterorhabditidae for biological control of soil pests
Turkish Journal of Biology, 2003Co-Authors: Selcuk Hazir, Harry K. Kaya, Patricia S Stock, Nevin KeskinAbstract:Several species of entomopathogenic nematodes in the families Steinernematidae (Steinernema) and Heterorhabditidae (Heterorhabditis) are being produced commercially and used as biological control agents against many soil insect pests and insects in cryptic habitats in many parts of the world. These nematodes, which are mutualistically associated with bacteria (Steinernema with Xenorhabdus bacteria and Heterorhabditis with Photorhabdus bacteria), offer a number of advantages because they have a broad host range, kill their hosts within 48 h, can be easily produced in vivo and in vitro, can be applied with standard spray equipment, are safe to humans and other non-target organisms, have no known negative effects on the environment, and do not require registration in many countries. We present a general overview on the current state of knowledge of entomopathogenic nematodes and their mutualistically associated bacteria. In addition, we examine the potential of these nematodes, which are commonly found in Turkish soils, as biological control agents against insect pests in Turkey.
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diversity and distribution of entomopathogenic nematodes rhabditida steinernematidae and Heterorhabditidae in turkey
Biodiversity and Conservation, 2003Co-Authors: Selcuk Hazir, Harry K. Kaya, Patricia S Stock, Nevin Keskin, Servet OzcanAbstract:The diversity and distribution of entomopathogenic nematodes in thefamilies Steinernematidae and Heterorhabditidae were assessed throughout anextensive soil survey in Turkey during 1999 and 2000. Entomopathogenic nematodeswere recovered from six out of seven regions sampled, with 22 positive sites(2%) out of 1080 sites sampled. A single nematode isolate was recovered at eachof the positive sites, of which 15 were steinernematid isolates and seven wereheterorhabditid isolates representing a total of four species. Based onmorphometric and molecular data, the nematode species were identified asHeterorhabditis bacteriophora, Steinernemafeltiae, S. affine, andSteinernema n. sp. The most common species was S.feltiae, which was isolated from 10 sites in six regions, followed byH. bacteriophora from seven sites in five regions,S. affine from four sites in two regions, andSteinernema n. sp. from one site. Heterorhabditisbacteriophora and S. feltiae have been found inmany parts of the world, whereas S. affine, so far, hasonly been recovered in Europe until our survey. Steinernemaaffine was isolated from the European (Marmara) as well as theAsiatic region (Middle Anatolia) of Turkey. A new undescribedSteinernema sp. was isolated from the most eastern region(East Anatolia) of Turkey. Soils of the positive sites were classified as sandy,sandy loam, or loam (68.2%) and sandy–clay–loam or clay loam (31.8%) and the pHranged from 5.6 to 7.9. The habitats from which the entomopathogenic nematodeswere isolated were broadly classified as disturbed (59.1%), which includedagricultural fields and poplar planted for lumber and wind breaks, andundisturbed (40.9%), which included pine forest, grassland, marsh and reed sites.Steinernema feltiae, S. affine, andH. bacteriophora were recovered from both disturbed andundisturbed habitats. The new Steinernema sp. was recoveredfrom grassland. Our survey showed that these nematodes occur widely throughoutTurkey, but at a frequency below that reported for other parts of the world.
Patricia S Stock - One of the best experts on this subject based on the ideXlab platform.
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in vivo and in vitro rearing of entomopathogenic nematodes steinernematidae and Heterorhabditidae
Journal of Visualized Experiments, 2014Co-Authors: John G Mcmullen, Patricia S StockAbstract:Entomopathogenic nematodes (EPN) (Steinernematidae and Heterorhabditidae) have a mutualistic partnership with Gram-negative Gamma-Proteobacteria in the family Enterobacteriaceae. Xenorhabdus bacteria are associated with steinernematids nematodes while Photorhabdus are symbionts of heterorhabditids. Together nematodes and bacteria form a potent insecticidal complex that kills a wide range of insect species in an intimate and specific partnership. Herein, we demonstrate in vivo and in vitro techniques commonly used in the rearing of these nematodes under laboratory conditions. Furthermore, these techniques represent key steps for the successful establishment of EPN cultures and also form the basis for other bioassays that utilize these organisms for research. The production of aposymbiotic (symbiont–free) nematodes is often critical for an in-depth and multifaceted approach to the study of symbiosis. This protocol does not require the addition of antibiotics and can be accomplished in a short amount of time with standard laboratory equipment. Nematodes produced in this manner are relatively robust, although their survivorship in storage may vary depending on the species used. The techniques detailed in this presentation correspond to those described by various authors and refined by P. Stock’s Laboratory, University of Arizona (Tucson, AZ, USA). These techniques are distinct from the body of techniques that are used in the mass production of these organisms for pest management purposes.
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soil sampling and isolation of entomopathogenic nematodes steinernematidae Heterorhabditidae
Journal of Visualized Experiments, 2014Co-Authors: Rousel A Orozco, Ming Min Lee, Patricia S StockAbstract:Entomopathogenic nematodes (a.k.a. EPN) represent a group of soil-inhabiting nematodes that parasitize a wide range of insects. These nematodes belong to two families: Steinernematidae and Heterorhabditidae. Until now, more than 70 species have been described in the Steinernematidae and there are about 20 species in the Heterorhabditidae. The nematodes have a mutualistic partnership with Enterobacteriaceae bacteria and together they act as a potent insecticidal complex that kills a wide range of insect species. Herein, we focus on the most common techniques considered for collecting EPN from soil. The second part of this presentation focuses on the insect-baiting technique, a widely used approach for the isolation of EPN from soil samples, and the modified White trap technique which is used for the recovery of these nematodes from infected insects. These methods and techniques are key steps for the successful establishment of EPN cultures in the laboratory and also form the basis for other bioassays that consider these nematodes as model organisms for research in other biological disciplines. The techniques shown in this presentation correspond to those performed and/or designed by members of S. P. Stock laboratory as well as those described by various authors.
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diversity and distribution of entomopathogenic nematodes steinernematidae Heterorhabditidae in south africa
Journal of Invertebrate Pathology, 2009Co-Authors: Justin Hatting, Patricia S Stock, Selcuk HazirAbstract:A total of 1506 soil samples from different habitats in seven geographic regions of South Africa were evaluated for the presence of entomopathogenic nematodes (EPN). Nematodes were isolated from 5% of the samples. Among the steinernematids, four Steinernema sp. were recovered including Steinernema khoisanae and three new undescribed species. Although steinernematids were recovered from both humid subtropical and semiarid regions, this family accounted for 80% of EPN recovered from the semiarid climate zones characterised by sandy, acidic soils. Eight isolates of S. khoisanae were recovered from the Western Cape province. One of the new undescribed steinernematids (Steinernema sp. 1) was recovered only from the Free State and KwaZulu-Natal provinces where humid subtropical conditions prevail and soils are generally less acidic with higher clay content. A high level of adaptation, however, was noted with Steinernema sp. 2, which was recovered from a wide range of soil conditions and habitats ranging from semiarid (Western Cape province) to humid subtropical (KwaZulu-Natal province). A third undescribed steinernematid, Steinernema sp. 3, seemed better adapted to heavier soils with more than 80% of isolates recovered from fruit orchards in the Free State province. Heterorhabditis bacteriophora was the only heterorhabditid recovered during this survey. This species was particularly prevalent in four provinces ranging from humid subtropical to semiarid regions. Isolation of EPN directly from insect cadavers included Steinernema sp. 2 and one H. bacteriophora from an unidentified white grub (Scarabaeidae) cadaver (i.e., dual infection) and H. bacteriophora from the black vine weevil, Otiorhynchus sulcatus.
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first record of entomopathogenic nematodes steinernematidae and Heterorhabditidae in costa rica
Journal of Invertebrate Pathology, 2005Co-Authors: Lorena Uribelorio, Marielos Mora, Patricia S StockAbstract:A survey of entomopathogenic nematodes was conducted in the north Pacific (Guanacaste Conservation Area) and southeast Caribbean (Gandoca-Manzanillo Natural Refuge) regions of Costa Rica. Out of a total of 41 soil samples, 5 were positive for entomopathogenic nematodes (20.5%), with 3 (12.3%) containing Steinernema and 2 (8.2%) Heterorhabditis isolates. Morphological and molecular studies were undertaken to characterize these isolates. The Heterorhabditis isolates were identified as Heterorhabditis indica and the three Steinernema isolates were identified as two new undescribed species. H. indica was recovered from a coastal dry forest. Steinernema n. sp. 1 was isolated from a rainforest valley, between volcanoes. Steinernema sp. n. 2 was isolated from sand dunes in the Caribbean Coast (Punta Uva) near the rainforest strip along the coast. Although limited to two geographic regions, this study suggests entomopathogenic nematodes may be diverse and perhaps widely distributed in Costa Rica. A more intensive survey, covering all geographic regions is currently undergoing.
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entomopathogenic nematodes steinernematidae and Heterorhabditidae for biological control of soil pests
Turkish Journal of Biology, 2003Co-Authors: Selcuk Hazir, Harry K. Kaya, Patricia S Stock, Nevin KeskinAbstract:Several species of entomopathogenic nematodes in the families Steinernematidae (Steinernema) and Heterorhabditidae (Heterorhabditis) are being produced commercially and used as biological control agents against many soil insect pests and insects in cryptic habitats in many parts of the world. These nematodes, which are mutualistically associated with bacteria (Steinernema with Xenorhabdus bacteria and Heterorhabditis with Photorhabdus bacteria), offer a number of advantages because they have a broad host range, kill their hosts within 48 h, can be easily produced in vivo and in vitro, can be applied with standard spray equipment, are safe to humans and other non-target organisms, have no known negative effects on the environment, and do not require registration in many countries. We present a general overview on the current state of knowledge of entomopathogenic nematodes and their mutualistically associated bacteria. In addition, we examine the potential of these nematodes, which are commonly found in Turkish soils, as biological control agents against insect pests in Turkey.
Ulrich Kuhlmann - One of the best experts on this subject based on the ideXlab platform.
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Influence of soil on the efficacy of entomopathogenic nematodes in reducing Diabrotica virgifera virgifera in maize
Journal of Pest Science, 2010Co-Authors: Stefan Toepfer, B. Kurtz, Ulrich KuhlmannAbstract:The use of entomopathogenic nematodes is one potential non-chemical approach to control the larvae of the invasive western corn rootworm ( Diabrotica virgifera virgifera LeConte, Coleoptera: Chrysomelidae) in Europe. This study investigated the efficacy of Heterorhabditis bacteriophora Poinar (Rhabditida: Heterorhabditidae), Heterorhabditis megidis Poinar, Jackson and Klein (Rh., Heterorhabditidae) and Steinernema feltiae Filipjev (Rh., Steinernematidae) in reducing D. v. virgifera as a function of soil characteristics. A field experiment was repeated four times in southern Hungary using artificially infested maize plants potted into three different soils. Sleeve gauze cages were used to assess the number of emerging adult D. v. virgifera from the treatments and untreated controls. Results indicate that nematodes have the potential to reduce D. v. virgifera larvae in most soils; however, their efficacy can be higher in maize fields with heavy clay or silty clay soils than in sandy soils, which is in contrast to the common assumption that nematodes perform better in sandy soils than in heavy soils.
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Comparative susceptibility of larval instars and pupae of the western corn rootworm to infection by three entomopathogenic nematodes
BioControl, 2008Co-Authors: B. Kurtz, Ulrich Kuhlmann, I. Hiltpold, T. C. J. Turlings, Stefan ToepferAbstract:As a first step towards the development of an ecologically rational control strategy against western corn rootworm (WCR; Diabrotica virgifera virgifera LeConte, Coleoptera: Chrysomelidae) in Europe, we compared the susceptibility of the soil living larvae and pupae of this maize pest to infection by three entomopathogenic nematode (EPN) species. In laboratory assays using sand-filled trays, Heterorhabditis bacteriophora Poinar and H. megidis Poinar, Jackson & Klein (both Rhabditida: Heterorhabditidae) caused comparable mortality among all three larval instars and pupae of D. v. virgifera . In soil-filled trays, H. bacteriophora was slightly more effective against third larval instars and pupae, and H. megidis against third larval instars, compared to other developmental stages. In both sand and soil, Steinernema feltiae (Filipjev) (Rh.: Steinernematidae) was least effective against second instars. In conclusion, all larval instars of D. v. virgifera show susceptibility to infection by all three nematodes tested. It is predicted that early application against young larval instars would be most effective at preventing root feeding damage by D. v. virgifera . Applications of nematodes just before or during the time period when third instars are predominant in the field are likely to increase control efficacy. According to our laboratory assays, H. bacteriophora and H. megidis appear to be the most promising candidates for testing in the field.
Dawn H Gouge - One of the best experts on this subject based on the ideXlab platform.
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parasitism of subterranean termites isoptera rhinotermitidae termitidae by entomopathogenic nematodes rhabditida steinernematidae Heterorhabditidae
Journal of Economic Entomology, 2006Co-Authors: Dawn H Gouge, Paul B BakerAbstract:Abstract In laboratory bioassays, Steinernema riobrave Cabanillas, Poinar and Raulston (355 strain), Steinernema carpocapsae (Weiser) (Mexican 33 strain), Steinernema feltiae (Filipjev) (UK76 strain), and Heterorhabditis bacteriophora Poinar (HP88 strain) were all capable of infecting and killing three termite species, Heterotermes aureus (Snyder), Gnathamitermes perplexus (Banks), and Reticulitermes flavipes (Kollar) in laboratory sand assays. S. riobrave and S. feltiae caused low levels of Reticulitermes virginicus (Banks) mortality under the same conditions. At 22°C, significant mortality (≥80%) of worker H. aureus and G. perplexus was caused by S. riobrave, in sand assays, indicating the need for further study. Because of the short assay time (3 d maximum), reproduction of the nematodes in the target host species was not recorded. All nematode species were observed to develop to fourth-stage juveniles, preadult stages, or adults in all termite species with the exception of R. virginicus. Only S. riobr...
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temporal association of entomopathogenic nematodes rhabditida steinernematidae and Heterorhabditidae and bacteria
Journal of Invertebrate Pathology, 2006Co-Authors: Dawn H Gouge, Jennifer SnyderAbstract:Galleria mellonella L. larvae were infected with three species (seven strains) of Steinernema spp. or three species (three strains) of Heterorhabditis spp. Infected larvae were incubated at 22, 27, and 32 degrees C. Larvae were dorsally dissected every 6h over a 48-h period. Hemolymph was collected and streaked on tryptic soy agar plates. Several non-symbiotic bacterial species were identified from infected insect cadavers: Enterobacter gergoviae, Vibrio spp., Pseudomonas fluorescens type C, Serratia marcescens, Citrobacter freundii, and Serratia proteomaculans. At 18-24 h incubation, the nematode-associated symbiont occurred almost exclusively. Bacterial associates generally appeared outside the 18-24 h window. Infective juveniles of Steinernema feltiae (Filipjev) (27), Steinernema riobrave Cabanillas, Poinar, and Raulston (Oscar), or Steinernema carpocapsae (Weiser) (Kapow) were left untreated, or surface sterilized using thimerosal, then pipetted under sterile conditions onto tryptic soy agar plates. Several additional species of associated bacteria were identified using this method compared with the less extensive range of species isolated from infected G. mellonella. There was no difference in bacterial species identified from non-sterile or surface sterilized nematodes, suggesting that the bacteria identified originated from either inside the nematode or between second and third stage juvenile cuticles. Infective juveniles of S. feltiae (Cowles), S. carpocapsae (Cowles), and H. bacteriophora Poinar (Cowles) were isolated from field samples. Nematodes were surface-sterilized using sodium hypochlorite, mixed with G. mellonella hemolymph, and pipetted onto Biolog BUG (with blood) agar. Only the relevant symbionts were isolated from the limited number of samples available. The nematodes were then cultured in the laboratory for 14 months (sub-cultured in G. mellonella 7-times). Other Enterobacteriaceae could then be isolated from the steinernematid nematodes including S. marcescens, Salmonella sp., and E. gergoviae, indicating the ability of the nematodes to associate with other bacteria in laboratory culture.
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parasitism of bark scorpion centruroides exilicauda scorpiones buthidae by entomopathogenic nematodes rhabditida steinernematidae Heterorhabditidae
Journal of Economic Entomology, 2005Co-Authors: Dawn H Gouge, Jennifer SnyderAbstract:In laboratory bioassays, Steinernema glaseri Steiner, Steinernema riobrave Cabanillas, Poinar & Raulston, Heterorhabditis bacteriophora Poinar, and Heterorhabditis marelatus Liu & Berry were capable of infecting and killing the bark scorpion, Centruroides exilicauda (Wood). Steinernema feltiae (Filipjev) and Steinernema carpocapsae (Weiser) failed to infect C. exilicauda at 22°C. S. glaseri, H. marelatus, and H. bacteriophora caused significant mortality at 22°C, indicating the potential role of these parasites as a biocontrol option. Efficacy of S. glaseri and H. bacteriophora was reduced in an assay conducted at 25°C. Only S. glaseri was able to reproduce in the target host. Dissection of scorpions at the end of the experimental periods revealed inactive juvenile S. riobrave, H. marelatus, and H. bacteriophora nematodes. Both mermithid and oxyurid nematodes have been documented as nematode parasites of scorpions, but rhabditids have not been reported until now. Field studies are warranted to assess the usefulness of entomopathogenic nematodes as biocontrol agents of bark scorpions.
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effect of temperature and lepidopteran host species on entomopathogenic nematode nematoda steinernematidae Heterorhabditidae infection
Environmental Entomology, 1999Co-Authors: Dawn H Gouge, L L Lee, T J HenneberryAbstract:Experiments were conducted to determine the effect of temperature on entomopathogenic nematode infection of in insect host. Late instars of Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), Heliothis virescens (F.) (Lepidoptera: Noctuidae), Trichoplusia ni (Hubner) (Lepidoptera: Noctuidae), and Spodoptera exigua (Hubner) (Lepidoptera: Noctuidae) were incubated at 10 temperatures ranging between 9.9 and 40 degrees C, and exposed to 150 infective juvenile entomopathogenic nematodes (Nematoda: Steinernematidae; Heterorhabditidae) per larva. The number of infecting Steinernema riobrave Cabanillas, Poinar & Raulston, S. carpocapsae (Weiser) (Kapow) and Heterorhabditis bacteriophora (Poinar) (Cruiser), nematodes was recorded. Temperature, nematode species, and target insect all significantly affected, the number of infective juvenile nematodes invading host insects. The temperature supporting the highest levels of nematode infection varied depending on insect host species. Larvae of P. gossypiella were then incubated at the same range of temperatures, and exposed to 2 dose rates (100 and 200 infective juveniles per larva) of S. riobrave, S. carpocapsae (Guardian). H. bacteriophora (Cruiser), or H. bacteriophora (Lawn Patrol). Increasing nematode dosage had no effect on the temperature at which nematode infection of P. gossypiella was highest. Doubling the nematode dose rate did not result in a significant increase in the number of infective juveniles infecting larvae for the nematode species tested with the exception of S. riobrave. The optimum temperature for the control of insect targets by a nematode will vary among target species. Assuming existing nematode temperature optima and applying the same conditions to untested insect species may not result in maximum biocontrol efficacy.