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Carmen Gutiérrez - One of the best experts on this subject based on the ideXlab platform.
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a laboratory study on the activity of steinernema feltiae Rhabditida steinernematidae rioja strain against horticultural insect pests
Journal of Pest Science, 2009Co-Authors: Raquel Camposherrera, Carmen GutiérrezAbstract:The potential of the entomopathogenic nematode Steinernema feltiae (Filipjev) (Rhabditida: Steinernematidae) Rioja strain was assessed under laboratory conditions. Last instar larvae of Leptinotarsa decemlineata Say (Coleptera: Chrysomelidae), Spodoptera littoralis Boisdouval (Lepidoptera: Noctuidae) and Trichoplusia ni Hubner (Lepidoptera: Noctuidae) were exposed to infective juveniles (IJs) under laboratory conditions. Larval mortality, days to larval death, infection cycle length, and reproductive potential were recorded. Efficacy was assessed performing dose–response experiments. The results indicate that control of L. decemlineata with S. feltiae Rioja strain is not economically profitable (LC50 = 99.61 IJs/cm2), whereas results obtained for T. ni (LC50 = 0.27 IJs/cm2) are promising. Due to the life cycle of this insect, the efficacy needs to be investigated in foliar application studies. The effects on S. littoralis (LC50 = 0.69 IJs/cm2) was considered the most suitable for development of the Rioja strain as a biocontrol agent for soil application.
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morphological and ecological characterization of steinernema feltiae Rhabditida steinernematidae rioja strain isolated from bibio hortulanus diptera bibionidae in spain
Journal of Nematology, 2006Co-Authors: Raquel Camposherrera, Miguel Escuer, Lee Robertson, Carmen GutiérrezAbstract:A new strain of Steinernema feltiae (Rhabditida: Steinernematidae) was isolated in La Rioja (Spain) from larvae of Bibio hortulanus (Diptera: Bibionidae). A comparative morphometric analysis of this new strain and four additional S. feltiae isolates was performed. Although significant differences in morphometric measurements were observed, PCR-RFLP profiles and sequence analysis of the ITS region of rDNA confirmed the identity of the new strain as A2 RFLP type of S. feltiae. A comparative morphometric study among nematodes from three hosts, Galleria mellonella (Lepidoptera: Pyralidae), Spodoptera littoralis (Lepidoptera: Noctuidae) and B. hortulanus, was conducted. Ecological characterization of the Rioja isolate was performed in G. mellonella larvae. Larval mortality was 75.3 and 78.12% in penetration and sand column assays, respectively, and the percentage of penetrating infective juveniles was 12.0 and 2.8% in these assays. Larval mortality in the one-on-one bioassay was 4.2%, and in exposure-time bioassays, it was 50% at 11.25 hours. Relationships between morphometric characteristics and host mortality are discussed for this new strain of entomopathogenic nematode.
Raquel Camposherrera - One of the best experts on this subject based on the ideXlab platform.
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biocontrol potential of the entomopathogenic nematodes heterorhabditis bacteriophora and steinernema carpocapsae on cucurbit fly dacus ciliatus diptera tephritidae
Biocontrol Science and Technology, 2013Co-Authors: Shokoofeh Kamali, Raquel Camposherrera, Javad Karimi, Mojtaba Hosseini, L W DuncanAbstract:Entomopathogenic nematodes (EPNs) from the families Steinernematidae and HereroRhabditidae are considered excellent biological control agents against many insects that damage the roots of crops. In a regional survey, native EPNs were isolated, and laboratory and greenhouse experiments were conducted to determine the infectivity of EPNs against the cucurbit fly, Dacus ciliatus Loew (Diptera: Tephritidae). Preliminary experiments showed high virulence by a native strain of Heterorhabditis bacteriophora Poinar (Rhabditida: HeteroRhabditidae) and a commercial strain of Steinernema carpocapsae Weiser (Rhabditida: Steinernematidae). These two strains were employed for further analysis while another native species, Steinernema feltiae, was excluded due to low virulence. In laboratory experiments, larvae and adult flies were susceptible to nematode infection, but both nematode species induced low mortality on pupae. S. carpocapsae had a significantly lower LC50 value against larvae than H. bacteriophora in filter...
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a laboratory study on the activity of steinernema feltiae Rhabditida steinernematidae rioja strain against horticultural insect pests
Journal of Pest Science, 2009Co-Authors: Raquel Camposherrera, Carmen GutiérrezAbstract:The potential of the entomopathogenic nematode Steinernema feltiae (Filipjev) (Rhabditida: Steinernematidae) Rioja strain was assessed under laboratory conditions. Last instar larvae of Leptinotarsa decemlineata Say (Coleptera: Chrysomelidae), Spodoptera littoralis Boisdouval (Lepidoptera: Noctuidae) and Trichoplusia ni Hubner (Lepidoptera: Noctuidae) were exposed to infective juveniles (IJs) under laboratory conditions. Larval mortality, days to larval death, infection cycle length, and reproductive potential were recorded. Efficacy was assessed performing dose–response experiments. The results indicate that control of L. decemlineata with S. feltiae Rioja strain is not economically profitable (LC50 = 99.61 IJs/cm2), whereas results obtained for T. ni (LC50 = 0.27 IJs/cm2) are promising. Due to the life cycle of this insect, the efficacy needs to be investigated in foliar application studies. The effects on S. littoralis (LC50 = 0.69 IJs/cm2) was considered the most suitable for development of the Rioja strain as a biocontrol agent for soil application.
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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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.
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Effect of steinernematid and heterorhabditid nematodes (Rhabditida: Steinernematidae and HeteroRhabditidae) on nontarget arthropods.
Environmental Entomology, 1991Co-Authors: Ramon Georgis, Harry K. Kaya, Randy GauglerAbstract:The effect of entomopathogenic nematodes on nontarget arthropods in the laboratory, field soils, and a stream were assessed. In the laboratory, adult predators were less susceptible to the nematodes Steinernema carpocapsae (Weiser) (Rhabditida: Steinernematidae) and Heterorhabditis bacteriophora Poinar (Rhabditida: HeteroRhabditidae) than the immature stages. In field tests, entomopathogenic nematodes that had significantly suppressed pest populations ( Popillia japonica Newman, Japanese beetle, Scapteriscus vicinus Scudder, tawny mole cricket, Otiorhynchus sulcatus (F.), black vine weevil, Delia radicum (L.), cabbage maggot, and Diabrotica virgifera virgifera LeConte, western corn rootworm) did not adversely affect the numbers of nontarget soil arthropods in comparison with the untreated control. In contrast, broad-spectrum chemical insecticides (isofenphos, ethoprop, or chlorpyrifos used as chemical checks) significantly reduced or showed a tendency to reduce nontarget arthropod populations. In a stream trial, S. carpocapsae significantly reduced black fly larval populations, but the nontarget insects often increased in the treatment sites. Decreases in nontarget populations were matched by approximately equal or greater reductions in the upstream controls. We conclude that entomopathogenic nematodes do not adversely affect nontarget arthropods when used for short-term control of insect pests.
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effect of host condition and soil texture on host finding by the entomogenous nematodes heterorhabditis bacteriophora Rhabditida heteroRhabditidae and steinernema carpocapsae Rhabditida steinernematidae
Environmental Entomology, 1991Co-Authors: Mary E Barbercheck, Harry K. KayaAbstract:Laboratory experiments were conducted to determine the effect of soil texture and condition of Galleria mellonella larvae (infected with Beauveria bassiana , uninfected and alive, or uninfected and killed by freezing) on host-finding by the entomogenous nematodes, Heterorhabditis bacteriophora and Steinernema carpocapsae, H. bacteriophora was more motile than S. carpocapsae in organic and fine sandy loam soils, but less motile in clay soil. In soil-filled tubes, H. bacteriophora and S. carpocapsae usually occurred more frequently near healthy hosts when healthy hosts were present in choice tests. When a Beauveria -infected host was included in a choice test, nematodes tended to occur more frequently at the host not infected with B. bassiana . This behavior may minimize antagonistic interactions between entomogenous nematodes and B. bassiana in soil.
Keyun Zhang - One of the best experts on this subject based on the ideXlab platform.
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serratia nematodiphila sp nov associated symbiotically with the entomopathogenic nematode heterorhabditidoides chongmingensis Rhabditida Rhabditidae
International Journal of Systematic and Evolutionary Microbiology, 2009Co-Authors: Chongxing Zhang, Jingrui Liu, Jie Sun, Shouyun Yang, Ren Lai, Huan Liu, Hui Liu, Fei Kan, Jing Sun, Keyun ZhangAbstract:A novel red-pigmented, Gram-negative, motile, fluorescent, rod-shaped strain, DZ0503SBS1(T), with a single lateral flagellum, was isolated from the intestine of the nematode Heterorhabditidoides chongmingensis. Comparative 16S rRNA gene sequence analysis indicated that the strain is a member of the genus Serratia, sharing highest sequence similarities with Serratia marcescens subsp. sakuensis JCM 11315(T) (99.8 %), S. marcescens subsp. marcescens DSM 30121(T) (99.5 %) and Serratia ureilytica LMG 22860(T) (98.3 %). Similarities between the rpoB gene sequence of strain DZ0503SBS1(T) and those of S. marcescens subsp. sakuensis JCM 11315(T), S. marcescens subsp. marcescens DSM 30121(T) and S. ureilytica LMG 22860(T) were 98.0, 97.4 and 98.3 %, respectively. DNA-DNA hybridization values of strain DZ0503SBS1(T) with S. marcescens subsp. sakuensis JCM 11315(T), S. marcescens subsp. marcescens DSM 30121(T) and S. ureilytica LMG 22860(T) were 68.2, 65.1 and 53.0 %, respectively. The major isoprenoid quinone of strain DZ0503SBS1(T) was Q-8 and the predominant fatty acids were C(16 : 0) (34.76 %), cyclo-C(17 : 0) (20.03 %) and cyclo-C(19 : 0)omega8c (17.24 %). The cyclo-C(19 : 0)omega8c content (17.24 %) was significantly different from those found in S. marcescens subsp. sakuensis JCM 11315(T) and S. marcescens subsp. marcescens DSM 30121(T). Some characteristics of strain DZ0503SBS1(T), i.e. fluorescence and its symbiotic association with nematodes, have not been reported previously in any species of the genus Serratia. Phenotypic and biochemical characteristics and molecular data show that strain DZ0503SBS1(T) represents a novel species, for which the name Serratia nematodiphila sp. nov. is proposed; the type strain is DZ0503SBS1(T) (=KCTC 22130(T) =CGMCC 1.6853(T)).
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heterorhabditidoides chongmingensis gen nov sp nov Rhabditida Rhabditidae a novel member of the entomopathogenic nematodes
Journal of Invertebrate Pathology, 2008Co-Authors: Chongxing Zhang, Jingrui Liu, Jie Sun, Shouyun Yang, Guofu Gao, Maosong Lin, Ren Lai, Keyun ZhangAbstract:During a recent soil sample survey in Eastern China, a new entomopathogenic nematode species, collected from the Chongming Islands in the southern-eastern area of Shanghai, was discovered. Morphological characteristics of different developmental stages of the nematode combined with molecular data showed that this nematode is a new genus of Rhabditidae, and described as Heterorhabditidoides chongmingensis gen. nov., sp. nov., for that it shares more morphological characteristics with heterorhabditids than with steinernematids. For males, the papillae formula of bursa is 1, 2, 3, 3, with constant papillae number in the terminal group, stoma tubular-shaped and about 1.5 head width; cheilorhabdions cuticularized, esophageal collar present and long, median bulb present. For infective juveniles, EP=90 (80-105)microm, ES=104 (92-120)microm, tail length=111 (89-159)microm, and a=19.1 (15-21). The percentages of the nucleotides A, T, C and G in the ITS1 regions of the new species are significantly different from those of heterorhabditids and other rhabditids. Molecular phylogenetic trees based on 18S rDNA and the internal transcribed spacer (ITS) sequences data revealed that the new entomopathogenic nematode species forms a monophyletic group, which is a sister group of the clade comprised of some genera of Rhabditidae.
Steven A. Nadler - One of the best experts on this subject based on the ideXlab platform.
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Asian horned frogs (Megophrys montana)
2016Co-Authors: Denise M. Imai, Steven A. Nadler, Deena Brenner, Taryn A. Donovan, Allan P. PessierAbstract:Abstract. Between 2006 and 2008, 4 captive Asian horned frogs (Megophrys montana) were diagnosed with ocular and neurologic disease associated with rhabditid nematodiasis. Mortality, either spontaneous or by humane euthanasia, was high (3/4, 75%). Gross and histologic findings included varying degrees of ulcerative keratitis, histiocytic uveitis and retinitis, meningoencephalomyelitis, and epidermal chromatophore (iridophore) hyperplasia with intralesional nematodes. Entry into the host was presumed to be by direct invasion of the skin and the cornea with migration through the optic nerve to the brain and spinal cord. One frog was diagnosed with rhabditid nematodiasis antemortem, and clinical signs and lesions in the frog did not progress after unilateral enucleation and anthelminthic treatment were completed. Gross and tissue morphology of the nematodes were consistent with the order Rhabditida. DNA was extracted separately from 2 individual nematodes that were isolated from frozen and ethanol-preserved eye and brain tissue. These DNA templates were used for polymerase chain reaction amplification and sequencing of nuclear 28S large subunit (LSU) and internal transcribed spacer (ITS) ribosomal DNA regions. Comparison of the LSU and ITS sequences to those deposited in GenBank revealed an exact match for Caenorhabditis elegans
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sensitivity of ribosomal rna character sampling in the phylogeny of Rhabditida
Journal of Nematology, 2015Co-Authors: Oleksandr Holovachov, Lauren Camp, Steven A. NadlerAbstract:Near-full-length 18S and 28S rRNA gene sequences were obtained for 33 nematode species. Datasets were constructed based on secondary structure and progressive multiple alignments, and clades were compared for phylogenies inferred by Bayesian and maximum likelihood methods. Clade comparisons were also made following removal of ambiguously aligned sites as determined using the program ProAlign. Different alignments of these data produced tree topologies that differed, sometimes markedly, when analyzed by the same inference method. With one exception, the same alignment produced an identical tree topology when analyzed by different methods. Removal of ambiguously aligned sites altered the tree topology and also reduced resolution. Nematode clades were sensitive to differences in multiple alignments, and more than doubling the amount of sequence data by addition of 28S rRNA did not fully mitigate this result. Although some individual clades showed substantially higher support when 28S data were combined with 18S data, the combined analysis yielded no statistically significant increases in the number of clades receiving higher support when compared to the 18S data alone. Secondary structure alignment increased accuracy in positional homology assignment and, when used in combination with paired-site substitution models, these structural hypotheses of characters and improved models of character state change yielded high levels of phylogenetic resolution. Phylogenetic results included strong support for inclusion of Daubaylia potomaca within Cephalobidae, whereas the position of Fescia grossa within Tylenchina varied depending on the alignment, and the relationships among Rhabditidae, Diplogastridae, and Bunonematidae were not resolved.
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monophyly of clade iii nematodes is not supported by phylogenetic analysis of complete mitochondrial genome sequences
BMC Genomics, 2011Co-Authors: Joongki Park, Tahera Sultana, Seokha Kang, Steven A. NadlerAbstract:The orders Ascaridida, Oxyurida, and Spirurida represent major components of zooparasitic nematode diversity, including many species of veterinary and medical importance. Phylum-wide nematode phylogenetic hypotheses have mainly been based on nuclear rDNA sequences, but more recently complete mitochondrial (mtDNA) gene sequences have provided another source of molecular information to evaluate relationships. Although there is much agreement between nuclear rDNA and mtDNA phylogenies, relationships among certain major clades are different. In this study we report that mtDNA sequences do not support the monophyly of Ascaridida, Oxyurida and Spirurida (clade III) in contrast to results for nuclear rDNA. Results from mtDNA genomes show promise as an additional independently evolving genome for developing phylogenetic hypotheses for nematodes, although substantially increased taxon sampling is needed for enhanced comparative value with nuclear rDNA. Ultimately, topological incongruence (and congruence) between nuclear rDNA and mtDNA phylogenetic hypotheses will need to be tested relative to additional independent loci that provide appropriate levels of resolution. For this comparative phylogenetic study, we determined the complete mitochondrial genome sequences of three nematode species, Cucullanus robustus (13,972 bp) representing Ascaridida, Wellcomia siamensis (14,128 bp) representing Oxyurida, and Heliconema longissimum (13,610 bp) representing Spirurida. These new sequences were used along with 33 published nematode mitochondrial genomes to investigate phylogenetic relationships among chromadorean orders. Phylogenetic analyses of both nucleotide and amino acid sequence datasets support the hypothesis that Ascaridida is nested within Rhabditida. The position of Oxyurida within Chromadorea varies among analyses; in most analyses this order is sister to the Ascaridida plus Rhabditida clade, with representative Spirurida forming a distinct clade, however, in one case Oxyurida is sister to Spirurida. Ascaridida, Oxyurida, and Spirurida (the sampled clade III taxa) do not form a monophyletic group based on complete mitochondrial DNA sequences. Tree topology tests revealed that constraining clade III taxa to be monophyletic, given the mtDNA datasets analyzed, was a significantly worse result. The phylogenetic hypotheses from comparative analysis of the complete mitochondrial genome data (analysis of nucleotide and amino acid datasets, and nucleotide data excluding 3rd positions) indicates that nematodes representing Ascaridida, Oxyurida and Spirurida do not share an exclusive most recent common ancestor, in contrast to published results based on nuclear ribosomal DNA. Overall, mtDNA genome data provides reliable support for nematode relationships that often corroborates findings based on nuclear rDNA. It is anticipated that additional taxonomic sampling will provide a wealth of information on mitochondrial genome evolution and sequence data for developing phylogenetic hypotheses for the phylum Nematoda.