A new class of ubiquitin extension proteins secreted by the dorsal pharyngeal gland in plant parasitic cyst nematodes.

Science.gov (United States)

Tytgat, Tom; Vanholme, Bartel; De Meutter, Jan; Claeys, Myriam; Couvreur, Marjolein; Vanhoutte, Isabelle; Gheysen, Greetje; Van Criekinge, Wim; Borgonie, Gaetan; Coomans, August; Gheysen, Godelieve

2004-08-01

By performing cDNA AFLP on pre- and early parasitic juveniles, we identified genes encoding a novel type of ubiquitin extension proteins secreted by the dorsal pharyngeal gland in the cyst nematode Heterodera schachtii. The proteins consist of three domains, a signal peptide for secretion, a mono-ubiquitin domain, and a short C-terminal positively charged domain. A gfp-fusion of this protein is targeted to the nucleolus in tobacco BY-2 cells. We hypothesize that the C-terminal peptide might have a regulatory function during syncytium formation in plant roots.

The AAP gene family for amino acid permeases contributes to development of the cyst nematode Heterodera schachtii in roots of Arabidopsis.

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Elashry, Abdelnaser; Okumoto, Sakiko; Siddique, Shahid; Koch, Wolfgang; Kreil, David P; Bohlmann, Holger

2013-09-01

The beet cyst nematode Heterodera schachtii is able to infect Arabidopsis plants and induce feeding sites in the root. These syncytia are the only source of nutrients for the nematodes throughout their life and are a nutrient sink for the host plant. We have studied here the role of amino acid transporters for nematode development. Arabidopsis contains a large number of different amino acid transporters in several gene families but those of the AAP family were found to be especially expressed in syncytia. Arabidopsis contains 8 AAP genes and they were all strongly expressed in syncytia with the exception of AAP5 and AAP7, which were slightly downregulated. We used promoter::GUS lines and in situ RT-PCR to confirm the expression of several AAP genes and LHT1, a lysine- and histidine-specific amino acid transporter, in syncytia. The strong expression of AAP genes in syncytia indicated that these transporters are important for the transport of amino acids into syncytia and we used T-DNA mutants for several AAP genes to test for their influence on nematode development. We found that mutants of AAP1, AAP2, and AAP8 significantly reduced the number of female nematodes developing on these plants. Our study showed that amino acid transport into syncytia is important for the development of the nematodes. Copyright © 2013 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

Suppression of NGB and NAB/ERabp1 in tomato modifies root responses to potato cyst nematode infestation.

Science.gov (United States)

Dąbrowska-Bronk, Joanna; Czarny, Magdalena; Wiśniewska, Anita; Fudali, Sylwia; Baranowski, Łukasz; Sobczak, Mirosław; Święcicka, Magdalena; Matuszkiewicz, Mateusz; Brzyżek, Grzegorz; Wroblewski, Tadeusz; Dobosz, Renata; Bartoszewski, Grzegorz; Filipecki, Marcin

2015-05-01

Plant-parasitic nematodes cause significant damage to major crops throughout the world. The small number of genes conferring natural plant resistance and the limitations of chemical control require the development of new protective strategies. RNA interference or the inducible over-expression of nematicidal genes provides an environment-friendly approach to this problem. Candidate genes include NGB, which encodes a small GTP-binding protein, and NAB/ERabp1, which encodes an auxin-binding protein, which were identified as being up-regulated in tomato roots in a transcriptome screen of potato cyst nematode (Globodera rostochiensis) feeding sites. Real-time reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization confirmed the localized up-regulation of these genes in syncytia and surrounding cells following nematode infection. Gene-silencing constructs were introduced into tomato, resulting in a 20%-98% decrease in transcription levels. Nematode infection tests conducted on transgenic plants showed 57%-82% reduction in the number of G. rostochiensis females in vitro and 30%-46% reduction in pot trials. Transmission electron microscopy revealed a deterioration of cytoplasm, and degraded mitochondria and plastids, in syncytia induced in plants with reduced NAB/ERabp1 expression. Cytoplasm in syncytia induced in plants with low NGB expression was strongly electron translucent and contained very few ribosomes; however, mitochondria and plastids remained intact. Functional impairments in syncytial cytoplasm of silenced plants may result from NGB's role in ribosome biogenesis; this was confirmed by localization of yellow fluorescent protein (YFP)-labelled NGB protein in nucleoli and co-repression of NGB in plants with reduced NAB/ERabp1 expression. These results demonstrate that NGB and NAB/ERabp1 play important roles in the development of nematode-induced syncytia. © 2014 BSPP AND JOHN WILEY & SONS LTD.

The Transcriptome of Nacobbus aberrans Reveals Insights into the Evolution of Sedentary Endoparasitism in Plant-Parasitic Nematodes

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Eves-van den Akker, Sebastian; Lilley, Catherine J.; Danchin, Etienne G. J.; Rancurel, Corinne; Cock, Peter J. A.; Urwin, Peter E.; Jones, John T.

2014-01-01

Within the phylum Nematoda, plant-parasitism is hypothesized to have arisen independently on at least four occasions. The most economically damaging plant-parasitic nematode species, and consequently the most widely studied, are those that feed as they migrate destructively through host roots causing necrotic lesions (migratory endoparasites) and those that modify host root tissue to create a nutrient sink from which they feed (sedentary endoparasites). The false root-knot nematode Nacobbus aberrans is the only known species to have both migratory endoparasitic and sedentary endoparasitic stages within its life cycle. Moreover, its sedentary stage appears to have characteristics of both the root-knot and the cyst nematodes. We present the first large-scale genetic resource of any false-root knot nematode species. We use RNAseq to describe relative abundance changes in all expressed genes across the life cycle to provide interesting insights into the biology of this nematode as it transitions between modes of parasitism. A multigene phylogenetic analysis of N. aberrans with respect to plant-parasitic nematodes of all groups confirms its proximity to both cyst and root-knot nematodes. We present a transcriptome-wide analysis of both lateral gene transfer events and the effector complement. Comparing parasitism genes of typical root-knot and cyst nematodes to those of N. aberrans has revealed interesting similarities. Importantly, genes that were believed to be either cyst nematode, or root-knot nematode, “specific” have both been identified in N. aberrans. Our results provide insights into the characteristics of a common ancestor and the evolution of sedentary endoparasitism of plants by nematodes. PMID:25123114

A novel serine protease, Sep1, from Bacillus firmus DS-1 has nematicidal activity and degrades multiple intestinal-associated nematode proteins.

Science.gov (United States)

Geng, Ce; Nie, Xiangtao; Tang, Zhichao; Zhang, Yuyang; Lin, Jian; Sun, Ming; Peng, Donghai

2016-04-27

Plant-parasitic nematodes (PPNs) cause serious harm to agricultural production. Bacillus firmus shows excellent control of PPNs and has been produced as a commercial nematicide. However, its nematicidal factors and mechanisms are still unknown. In this study, we showed that B. firmus strain DS-1 has high toxicity against Meloidogyne incognita and soybean cyst nematode. We sequenced the whole genome of DS-1 and identified multiple potential virulence factors. We then focused on a peptidase S8 superfamily protein called Sep1 and demonstrated that it had toxicity against the nematodes Caenorhabditis elegans and M. incognita. The Sep1 protein exhibited serine protease activity and degraded the intestinal tissues of nematodes. Thus, the Sep1 protease of B. firmus is a novel biocontrol factor with activity against a root-knot nematode. We then used C. elegans as a model to elucidate the nematicidal mechanism of Sep1, and the results showed that Sep1 could degrade multiple intestinal and cuticle-associated proteins and destroyed host physical barriers. The knowledge gained in our study will lead to a better understanding of the mechanisms of B. firmus against PPNs and will aid in the development of novel bio-agents with increased efficacy for controlling PPNs.

Interactions of Heterodera glycines, Macrophomina phaseolina, and Mycorrhizal Fungi on Soybean in Kansas.

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Winkler, H E; Hetrick, B A; Todd, T C

1994-12-01

The impact of naturally occurring arbuscular mycorrhizal fungi on soybean growth and their interaction with Heterodera glycines were evaluated in nematode-infested and uninfested fields in Kansas. Ten soybean cultivars from Maturity Groups III-V with differential susceptibility to H. glycines were treated with the fungicide benomyl to suppress colonization by naturally occurring mycorrhizal fungi and compared with untreated control plots. In H. glycines-infested soil, susceptible cultivars exhibited 39% lower yields, 28% lower colonization by mycorrhizal fungi, and an eightfold increase in colonization by the charcoal rot fungus, Macrophomina phaseolina, compared with resistant cultivars. In the absence of the nematode, susceptible cultivars exhibited 10% lower yields than resistant cultivars, root colonization of resistant vs. susceptible soybean by mycorrhizal fungi varied with sampling date, and there were no differences in colonization by M. phaseolina between resistant and susceptible cultivars. Benomyl application resulted in 19% greater root growth and 9% higher seed yields in H. glycines-infested soil, but did not affect soybean growth and yield in the absence of the nematode. Colonization of soybean roots by mycorrhizal fungi was negatively correlated with H. glycines population densities due to nematode antagonism to the mycorrhizal fungi rather than suppression of nematode populations. Soybean yields were a function of the pathogenic effects of H. glycines and M. phaseolina, and, to a lesser degree, the stimulatory effects of mycorrhizal fungi.

In planta processing and glycosylation of a nematode CLE effector and its interaction with a CLV2-like receptor to promote parasitism

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Like other biotrophic plant pathogens, plant-parasitic nematodes secrete effector proteins into host cells to facilitate infection. Effector proteins that mimic plant CLAVATA3/ESR (CLE)-like proteins have been identified in several cyst nematodes including the potato cyst nematode (PCN); however, th...

Using SNP markers to dissect linkage disequilibrium at a major quantitative trait locus for resistance to the potato cyst nematode Globodera pallida on potato chromosome V

NARCIS (Netherlands)

Achenbach, U.; Caldas Paulo, M.J.; Ilarionova, E.; Lübeck, J.; Strahwald, J.; Tacke, E.; Hofferbert, H.R.

2009-01-01

The damage caused by the parasitic root cyst nematode Globodera pallida is a major yield-limiting factor in potato cultivation . Breeding for resistance is facilitated by the PCR-based marker 'HC', which is diagnostic for an allele conferring high resistance against G. pallida pathotype Pa2/3 that

Alternative splicing: a novel mechanism of regulation identified in the chorismate mutase gene of the potato cyst nematode Globodera rostochiensis.

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Lu, Shun-Wen; Tian, Duanhua; Borchardt-Wier, Harmony B; Wang, Xiaohong

2008-11-01

Chorismate mutase (CM) secreted from the stylet of plant-parasitic nematodes plays an important role in plant parasitism. We isolated and characterized a new nematode CM gene (Gr-cm-1) from the potato cyst nematode, Globodera rostochiensis. The Gr-cm-1 gene was found to exist in the nematode genome as a single-copy gene that has two different alleles, Gr-cm-1A and Gr-cm-1B, both of which could give rise to two different mRNA transcripts of Gr-cm-1 and Gr-cm-1-IRII. In situ mRNA hybridization showed that the Gr-cm-1 gene was exclusively expressed within the subventral oesophageal gland cells of the nematode. Gr-cm-1 was demonstrated to encode a functional CM (GR-CM-1) potentially having a dimeric structure as the secreted bacterial *AroQ CMs. Gr-cm-1-IRII, generated by retention of intron 2 of the Gr-cm-1 pre-mRNA through alternative splicing (AS), would encode a truncated protein (GR-CM-1t) lacking the CM domain with no CM activity. The quantitative real-time reverse transcription-PCR assay revealed that splicing of the Gr-cm-1 gene was developmentally regulated; Gr-cm-1 was up-regulated whereas Gr-cm-1-IRII was down-regulated in early nematode parasitic stages compared to the preparasitic juvenile stage. Low-temperature SDS-PAGE analysis revealed that GR-CM-1 could form homodimers when expressed in Escherichia coli and the dimerization domain was retained in the truncated GR-CM-1t protein. The specific interaction between the two proteins was demonstrated in yeast. Our data suggested that the novel splice variant might function as a dominant negative isoform through heterodimerization with the full-length GR-CM-1 protein and that AS may represent an important mechanism for regulating CM activity during nematode parasitism.

Prevalence of Pasteuria SP. on Renfirom Nematode in a Georgia Cotton Field

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Pasteuria species are bacterial parasites of nematodes and have been associated with suppression of root-knot, sting, and cyst nematode populations. Little is known about the Pasteuria sp. infecting the reniform nematode. While sampling a cotton field study near Cochran, GA, we found Pasteuria spo...

PsVPS1, a dynamin-related protein, is involved in cyst germination and soybean infection of Phytophthora sojae.

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Delong Li

Full Text Available Plant pathogens secrete effector proteins to suppress plant immunity. However, the mechanism by which oomycete pathogens deliver effector proteins during plant infection remains unknown. In this report, we characterized a Phytophthora sojae vps1 gene. This gene encodes a homolog of the Saccharomyces cerevisiae vacuolar protein sorting gene vps1 that mediates budding of clathrin-coated vesicles from the late Golgi, which are diverted from the general secretory pathway to the vacuole. PsVPS1-silenced mutants were generated using polyethylene glycol-mediated protoplast stable transformation and were viable but had reduced extracellular protein activity. The PsVPS1-silenced mutants showed impaired hyphal growth, and the shapes of the vacuoles were highly fragmented. Silencing of PsVPS1 affected cyst germination as well as the polarized growth of germinated cysts. Silenced mutants showed impaired invasion of susceptible soybean plants regardless of wounding. These results suggest that PsVPS1 is involved in vacuole morphology and cyst development. Moreover, it is essential for the virulence of P. sojae and extracellular protein secretion.

The transcriptome of Nacobbus aberrans reveals insights into the evolution of sedentary endoparasitism in plant-parasitic nematodes.

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Eves-van den Akker, Sebastian; Lilley, Catherine J; Danchin, Etienne G J; Rancurel, Corinne; Cock, Peter J A; Urwin, Peter E; Jones, John T

2014-08-13

Within the phylum Nematoda, plant-parasitism is hypothesized to have arisen independently on at least four occasions. The most economically damaging plant-parasitic nematode species, and consequently the most widely studied, are those that feed as they migrate destructively through host roots causing necrotic lesions (migratory endoparasites) and those that modify host root tissue to create a nutrient sink from which they feed (sedentary endoparasites). The false root-knot nematode Nacobbus aberrans is the only known species to have both migratory endoparasitic and sedentary endoparasitic stages within its life cycle. Moreover, its sedentary stage appears to have characteristics of both the root-knot and the cyst nematodes. We present the first large-scale genetic resource of any false-root knot nematode species. We use RNAseq to describe relative abundance changes in all expressed genes across the life cycle to provide interesting insights into the biology of this nematode as it transitions between modes of parasitism. A multigene phylogenetic analysis of N. aberrans with respect to plant-parasitic nematodes of all groups confirms its proximity to both cyst and root-knot nematodes. We present a transcriptome-wide analysis of both lateral gene transfer events and the effector complement. Comparing parasitism genes of typical root-knot and cyst nematodes to those of N. aberrans has revealed interesting similarities. Importantly, genes that were believed to be either cyst nematode, or root-knot nematode, "specific" have both been identified in N. aberrans. Our results provide insights into the characteristics of a common ancestor and the evolution of sedentary endoparasitism of plants by nematodes. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

The miRNAome dynamics during developmental and metabolic reprogramming of tomato root infected with potato cyst nematode.

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Koter, Marek D; Święcicka, Magdalena; Matuszkiewicz, Mateusz; Pacak, Andrzej; Derebecka, Natalia; Filipecki, Marcin

2018-03-01

Cyst-forming plant-parasitic nematodes are pests threatening many crops. By means of their secretions cyst nematodes induce the developmental and metabolic reprogramming of host cells that lead to the formation of a syncytium, which is the sole food source for growing nematodes. The in depth micro RNA (miRNA) dynamics in the syncytia induced by Globodera rostochiensis in tomato roots was studied. The miRNAomes were obtained from syncytia covering the early and intermediate developmental stages, and were the subject of differential expression analysis. The expression of 1235 miRNAs was monitored. The fold change (log 2 FC) ranged from -7.36 to 8.38, indicating that this transcriptome fraction was very variable. Moreover, we showed that the DE (differentially expressed) miRNAs do not fully overlap between the selected time points, suggesting infection stage specific regulation by miRNA. The correctness of RNA-seq expression profiling was confirmed by qRT-PCR (quantitative Real Time Polymerase Chain Reaction) for seven miRNA species. Down- and up-regulated miRNA species, including their isomiRs, were further used to identify their potential targets. Among them there are a large number of transcription factors linked to different aspects of plant development belonging to gene families, such as APETALA2 (AP2), SQUAMOSA (MADS-box), MYB, GRAS, and AUXIN RESPONSE FACTOR (ARF). The substantial portion of potential target genes belong to the NB-LRR and RLK (RECEPTOR-LIKE KINASE) families, indicating the involvement of miRNA mediated regulation in defense responses. We also collected the evidence for target cleavage in the case of 29 miRNAs using one of three alternative methods: 5' RACE (5' Rapid Amplification of cDNA Ends), a search of tasiRNA within our datasets, and the meta-analysis of tomato degradomes in the GEO (Gene Expression Omnibus) database. Eight target transcripts showed a negative correlation with their respective miRNAs at two or three time points. These

Pasteuria Nishizawae Studies in Tennessee

Science.gov (United States)

Spores of Pasteuria nishizawae were first recovered in Tennessee in 2008 attached to soybean cyst nematode juveniles, Heterodera glycines, and inside cysts extracted from soil collected at Ames Plantation, Grand Junction, TN. The field had a 15% increase from 1997 through 2004 in number of samples ...

Statistical analysis of nematode counts from interlaboratory proficiency tests

NARCIS (Netherlands)

Berg, van den W.; Hartsema, O.; Nijs, Den J.M.F.

2014-01-01

A series of proficiency tests on potato cyst nematode (PCN; n=29) and free-living stages of Meloidogyne and Pratylenchus (n=23) were investigated to determine the accuracy and precision of the nematode counts and to gain insights into possible trends and potential improvements. In each test, each

Techniques for characterization and eradication of potato cyst nematode: a review.

Science.gov (United States)

Bairwa, Aarti; Venkatasalam, E P; Sudha, R; Umamaheswari, R; Singh, B P

2017-09-01

Correct identification of species and pathotypes is must for eradication of potato cyst nematodes (PCN). The identification of PCN species after completing the life cycle is very difficult because it is based on morphological and morphometrical characteristics. Genetically different populations of PCN are morphologically same and differentiated based on the host differential study. Later on these traditional techniques have been replaced by biochemical techniques viz, one and two dimensional gel electrophoresis, capillary gel electrophoresis, isozymes, dot blot hybridization and isoelectric focusing etc. to distinguish both the species. One and two dimensional gel electrophoresis has used to examine inter- and intra-specific differences in proteins of Globodera rostochiensis and G. pallida . Now application of PCR and DNA based characterization techniques like RAPD, AFLP and RFLP are the important tools for differentiating inter- and intra specific variation in PCN and has given opportunities to accurate identification of PCN. For managing the PCN, till now we are following integrated pest management (IPM) strategies, however these strategies are not effective to eradicate the PCN. Therefore to eradicate the PCN we need noval management practices like RNAi (RNA interference) or Gene silencing.

Structural and functional diversity of CLAVATA3/ESR (CLE)-like genes from the potato cyst nematode Globodera rostochiensis.

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Lu, Shun-Wen; Chen, Shiyan; Wang, Jianying; Yu, Hang; Chronis, Demosthenis; Mitchum, Melissa G; Wang, Xiaohong

2009-09-01

Plant CLAVATA3/ESR-related (CLE) peptides have diverse roles in plant growth and development. Here, we report the isolation and functional characterization of five new CLE genes from the potato cyst nematode Globodera rostochiensis. Unlike typical plant CLE peptides that contain a single CLE motif, four of the five Gr-CLE genes encode CLE proteins with multiple CLE motifs. These Gr-CLE genes were found to be specifically expressed within the dorsal esophageal gland cell of nematode parasitic stages, suggesting a role for their encoded proteins in plant parasitism. Overexpression phenotypes of Gr-CLE genes in Arabidopsis mimicked those of plant CLE genes, and Gr-CLE proteins could rescue the Arabidopsis clv3-2 mutant phenotype when expressed within meristems. A short root phenotype was observed when synthetic GrCLE peptides were exogenously applied to roots of Arabidopsis or potato similar to the overexpression of Gr-CLE genes in Arabidopsis and potato hairy roots. These results reveal that G. rostochiensis CLE proteins with either single or multiple CLE motifs function similarly to plant CLE proteins and that CLE signaling components are conserved in both Arabidopsis and potato roots. Furthermore, our results provide evidence to suggest that the evolution of multiple CLE motifs may be an important mechanism for generating functional diversity in nematode CLE proteins to facilitate parasitism.

Use of chemical flocculation and nested PCR for Heterodera glycines detection in DNA extracts from field soils with low population densities

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The soybean cyst nematode (SCN) Heterodera glycines is a major pathogen of soybean world-wide. Distinction between SCN and other members of H. schachtii sensu stricto group based on morphology is a tedious task. A molecular assay was developed to detect SCN in field soils with low population densiti...

Spatial and temporal expression patterns of auxin response transcription factors in the syncytium induced by the beet cyst nematode Heterodera schachtii in Arabidopsis.

Science.gov (United States)

Hewezi, Tarek; Piya, Sarbottam; Richard, Geoffrey; Rice, J Hollis

2014-09-01

Plant-parasitic cyst nematodes induce the formation of a multinucleated feeding site in the infected root, termed the syncytium. Recent studies point to key roles of the phytohormone auxin in the regulation of gene expression and establishment of the syncytium. Nevertheless, information about the spatiotemporal expression patterns of the transcription factors that mediate auxin transcriptional responses during syncytium formation is limited. Here, we provide a gene expression map of 22 auxin response factors (ARFs) during the initiation, formation and maintenance stages of the syncytium induced by the cyst nematode Heterodera schachtii in Arabidopsis. We observed distinct and overlapping expression patterns of ARFs throughout syncytium development phases. We identified a set of ARFs whose expression is predominantly located inside the developing syncytium, whereas others are expressed in the neighbouring cells, presumably to initiate specific transcriptional programmes required for their incorporation within the developing syncytium. Our analyses also point to a role of certain ARFs in determining the maximum size of the syncytium. In addition, several ARFs were found to be highly expressed in fully developed syncytia, suggesting a role in maintaining the functional phenotype of mature syncytia. The dynamic distribution and overlapping expression patterns of various ARFs seem to be essential characteristics of ARF activity during syncytium development. © 2014 BSPP AND JOHN WILEY & SONS LTD.

Cactodera chenopodiae (Nematoda: Heteroderidae), a new species of cyst nematode parasitizing common lambsquarter (Chenopodium album) in Liaoning, China.

Science.gov (United States)

Feng, Yaxing; Wang, Dong; Xiao, Dongxue; Pereira, Tiago josÉ; Xuan, Yuanhu; Wang, Yuanyuan; Liu, Xiaoyu; Chen, Lijie; Duan, Yuxi; Zhu, Xiaofeng

2018-04-11

A new species of cyst nematode, Cactodera chenopodiae n. sp., parasitizing common lambsquarter, Chenopodium album L., is described from native vegetation in Liaoning, China. Cactodera chenopodiae n. sp. has a circumfenestrate pattern typical of the genus and is morphologically similar to C. cacti Krall Krall, 1978. However, in the new species, females and cysts show a larger L/W ratio whereas second-stage juveniles (J2s) have a longer hyaline region. The new species is also morphologically similar to C. milleri Graney Bird, 1990, but the J2s differ by a larger b ratio and longer tail. Based on DNA sequences of the 28S and ITS rRNA, C. chenopodiae n. sp. comes close to C. estonica Krall Krall, 1978, although it is distinct from the latter with respect to the presence of a punctate eggshell and larger b ratio in the J2s. Although morphometric comparisons with additional Cactodera species show the overlapping of diagnostic morphological characters, our phylogenetic analyses based on both rRNA genes support C. chenopodiae n. sp. as a unique lineage.

Females and males of root-parasitic cyst nematodes induce different symplasmic connections between their syncytial feeding cells and the phloem in Arabidopsis thaliana.

Science.gov (United States)

Hofmann, Julia; Grundler, Florian M W

2006-01-01

Root syncytia induced by the beet cyst nematode Heterodera schachtii were thought to be symplasmically isolated. A recent study with mobile and immobile GFP constructs expressed in transgenic Arabidopsis plants under the control of pAtSUC2 showed that only mobile GFP could be detected in syncytia and suggested the existence of plasmodesmata between syncytia and the phloem. In the present study the existence of plasmodesmata between syncytia and the phloem is proven by grafting experiments. This technique rules out the possibility that GFP accumulation in syncytia is due to GFP expression in syncytia. Mobile GFP could be followed from transgenic scions carrying a pAtSUC2-gfp fusion construct via wild-type rootstocks into nematode-induced syncytia. While GFP could be detected in all syncytia associated to female nematodes, it was never observed in syncytia of male juveniles. As no GFP-mRNA could be detected in the rootstock we postulate that GFP as protein entered syncytia of females via plasmodesmata, while the protein was excluded from syncytia of male juveniles by plasmodesmata with a lower size exclusion limit.

Economic impact from unrestricted spread of potato cyst nematodes in australia.

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Hodda, M; Cook, D C

2009-12-01

ABSTRACT Potato cyst nematodes (PCN) (Globodera spp.) are quarantine pests with serious potential economic consequences. Recent new detections in Australia, Canada, and the United States have focussed attention on the consequences of spread and economic justifications for alternative responses. Here, a full assessment of the economic impact of PCN spread from a small initial incursion is presented. Models linking spread, population growth, and economic impact are combined to estimate costs of spread without restriction in Australia. Because the characteristics of the Australian PCN populations are currently unknown, the known ranges of parameters were used to obtain cost scenarios, an approach which makes the model predictions applicable generally. Our analysis indicates that mean annual costs associated with spread of PCN would increase rapidly initially, associated with increased testing. Costs would then increase more slowly to peak at over AUD$20 million per year approximately 10 years into the future. Afterward, this annual cost would decrease slightly due to discounting factors. Mean annual costs over 20 years were $18.7 million, with a 90% confidence interval between AUD$11.9 million and AUD$27.0 million. Thus, cumulative losses to Australian agriculture over 20 years may exceed $370 million without action to prevent spread of PCN and entry to new areas.

Characterization of cereal cyst nematodes (Heterodera spp. in Morocco based on morphology, morphometrics and rDNA-ITS sequence analysis

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Mokrini Fouad

2017-09-01

Full Text Available Morphological and molecular diversity among 11 populations of cereal cyst nematodes from different wheat production areas in Morocco was investigated using light microscopy, species-specific primers, complemented by the ITS-rDNA sequences. Morphometrics of cysts and second-stage juveniles (J2s were generally within the expected ranges for Heterodera avenae; only the isolate from Aïn Jmaa showed morphometrics conforming to those of H. latipons. When using species-specific primers for H. avenae and H. latipons, the specific bands of 109 bp and 204 bp, respectively, confirmed the morphological identification. In addition, the internal transcribed spacer (ITS regions were sequenced to study the diversity of the 11 populations. These sequences were compared with those of Heterodera species available in the GenBank database (www.ncbi.nlm.nih.gov and confirmed again the identity of the species. Ten sequences of the ITS-rDNA were similar (99–100% to the sequences of H. avenae published in GenBank and three sequences, corresponding with one population, were similar (97–99% to H. latipons.

Natural product synthesis: Making nematodes nervous

Science.gov (United States)

Snyder, Scott A.

2011-06-01

A highly inventive route for the synthesis of a key substance that stimulates potato cyst nematodes to hatch has been developed. This discovery has potential to impact food supplies, as treatment of crops with this compound could alleviate the devastating effect of these parasites.

Parasitic nematodes modulate PIN-mediated auxin transport to facilitate infection.

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Wim Grunewald

2009-01-01

Full Text Available Plant-parasitic nematodes are destructive plant pathogens that cause significant yield losses. They induce highly specialized feeding sites (NFS in infected plant roots from which they withdraw nutrients. In order to establish these NFS, it is thought that the nematodes manipulate the molecular and physiological pathways of their hosts. Evidence is accumulating that the plant signalling molecule auxin is involved in the initiation and development of the feeding sites of sedentary plant-parasitic nematodes. Intercellular transport of auxin is essential for various aspects of plant growth and development. Here, we analysed the spatial and temporal expression of PIN auxin transporters during the early events of NFS establishment using promoter-GUS/GFP fusion lines. Additionally, single and double pin mutants were used in infection studies to analyse the role of the different PIN proteins during cyst nematode infection. Based on our results, we postulate a model in which PIN1-mediated auxin transport is needed to deliver auxin to the initial syncytial cell, whereas PIN3 and PIN4 distribute the accumulated auxin laterally and are involved in the radial expansion of the NFS. Our data demonstrate that cyst nematodes are able to hijack the auxin distribution network in order to facilitate the infection process.

Parasitic nematodes modulate PIN-mediated auxin transport to facilitate infection.

Science.gov (United States)

Grunewald, Wim; Cannoot, Bernard; Friml, Jirí; Gheysen, Godelieve

2009-01-01

Plant-parasitic nematodes are destructive plant pathogens that cause significant yield losses. They induce highly specialized feeding sites (NFS) in infected plant roots from which they withdraw nutrients. In order to establish these NFS, it is thought that the nematodes manipulate the molecular and physiological pathways of their hosts. Evidence is accumulating that the plant signalling molecule auxin is involved in the initiation and development of the feeding sites of sedentary plant-parasitic nematodes. Intercellular transport of auxin is essential for various aspects of plant growth and development. Here, we analysed the spatial and temporal expression of PIN auxin transporters during the early events of NFS establishment using promoter-GUS/GFP fusion lines. Additionally, single and double pin mutants were used in infection studies to analyse the role of the different PIN proteins during cyst nematode infection. Based on our results, we postulate a model in which PIN1-mediated auxin transport is needed to deliver auxin to the initial syncytial cell, whereas PIN3 and PIN4 distribute the accumulated auxin laterally and are involved in the radial expansion of the NFS. Our data demonstrate that cyst nematodes are able to hijack the auxin distribution network in order to facilitate the infection process.

Survey of crop losses in response to phytoparasitic nematodes in the United States for 1994.

Science.gov (United States)

Koenning, S R; Overstreet, C; Noling, J W; Donald, P A; Becker, J O; Fortnum, B A

1999-12-01

Previous reports of crop losses to plant-parasitic nematodes have relied on published results of survey data based on certain commodities, including tobacco, peanuts, cotton, and soybean. Reports on crop-loss assessment by land-grant universities and many commodity groups generally are no longer available, with the exception of the University of Georgia, the Beltwide Cotton Conference, and selected groups concerned with soybean. The Society of Nematologists Extension Committee contacted extension personnel in 49 U.S. states for information on estimated crop losses caused by plant-parasitic nematodes in major crops for the year 1994. Included in this paper are survey results from 35 states on various crops including corn, cotton, soybean, peanut, wheat, rice, sugarcane, sorghum, tobacco, numerous vegetable crops, fruit and nut crops, and golf greens. The data are reported systematically by state and include the estimated loss, hectarage of production, source of information, nematode species or taxon when available, and crop value. The major genera of phytoparasitic nematodes reported to cause crop losses were Heterodera, Hoplolaimus, Meloidogyne, Pratylenchus, Rotylenchulus, and Xiphinema.

Nematóides que parasitam a soja na região de Bauru Nematode parasites of soybean in the Bauru region

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Luiz Gonzaga E. Lordello

1956-01-01

Full Text Available Entre os sérios fatôres que atuam contra a expansão da cultura da soja no Estado de São Paulo, acha-se o representado por nematóides parasitos. Dêstes, os que mais têm atraído a atenção dos cultivadores e fitopatologistas são as espécies formadoras de galhas no sistema radicular (Meloidogyne spp.. O estudo do material atacado coligido em Bauru revelou que, naquela região, três formas se acham envolvidas, a saber : Pratylenchus sp., Meloidogyne incognita (Kofoid & White, 1919 Chitwood, 1949 e M. javanica bauruensis n. subsp. Neste trabalho é estudada a nova subespécie, sendo também apresentadas algumas observações sobre a população de M. incognita.One of the serious detriments to soybean (Glycine max (L. Merr. cultivation in the State of S. Paulo, Brazil, are root-parasitic nematodes. A study of infected material collected at Bauru, where at least two distinct soybean varieties were cultivated, disclosed that three forms were involved: a meadow nematode (Pralylenchus sp. and two root-knot nematodes (Meloidogyne incognita (Kofoid & White, 1919 Chitwood, 1949, and M. javanica bauruensis n. subsp.. Silva, Lordello & Miyasaka (3 published some observations about the resistance of several soybean varieties to the attacks by root-knot nematodes in Campinas. A detailed study of the nematodes involved in those experiments, which were considered as related do M. incognita, has not yet been made. One of the varieties tested, La 41-1219, proved to be resistant, thereby providing promising material for further studies and breeding. Unfortunately, such a variety when planted in Bauru, was severely attacked by a root-knot species, which is identified as M. incognita. Attacks by M. javanica bauruensis was not noted in that variety but was noted in another variety (Abura growing adjacent in the same field. The host preference of those two nematodes was specific and very marked. M. incognita attacked only var. La 41-1219 and M. javanica

The suppression of tomato defence response genes upon potato cyst nematode infection indicates a key regulatory role of miRNAs.

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Święcicka, Magdalena; Skowron, Waldemar; Cieszyński, Piotr; Dąbrowska-Bronk, Joanna; Matuszkiewicz, Mateusz; Filipecki, Marcin; Koter, Marek Daniel

2017-04-01

Potato cyst nematode Globodera rostochiensis is an obligate parasite of solanaceous plants, triggering metabolic and morphological changes in roots which may result in substantial crop yield losses. Previously, we used the cDNA-AFLP to study the transcriptional dynamics in nematode infected tomato roots. Now, we present the rescreening of already published, upregulated transcript-derived fragment dataset using the most current tomato transcriptome sequences. Our reanalysis allowed to add 54 novel genes to 135, already found as upregulated in tomato roots upon G. rostochiensis infection (in total - 189). We also created completely new catalogue of downregulated sequences leading to the discovery of 76 novel genes. Functional classification of candidates showed that the 'wound, stress and defence response' category was enriched in the downregulated genes. We confirmed the transcriptional dynamics of six genes by qRT-PCR. To place our results in a broader context, we compared the tomato data with Arabidopsis thaliana, revealing similar proportions of upregulated and downregulated genes as well as similar enrichment of defence related transcripts in the downregulated group. Since transcript suppression is quite common in plant-nematode interactions, we assessed the possibility of miRNA-mediated inverse correlation on several tomato sequences belonging to NB-LRR and receptor-like kinase families. The qRT-PCR of miRNAs and putative target transcripts showed an opposite expression pattern in 9 cases. These results together with in silico analyses of potential miRNA targeting to the full repertoire of tomato R-genes show that miRNA mediated gene suppression may be a key regulatory mechanism during nematode parasitism. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Nematodes from Achatina fulica Bowdich, 1822 (Mollusca: Gastropoda in Argentina

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Valente R.

2016-03-01

Full Text Available The aim of this study is to describe the nematode cysts and larvae found in Achatina fulica, the giant African snail, in the northeast of Argentina. A total of 373 snails were collected from the cities of Puerto Iguazú and Corrientes. Cysts (N= 2958 containing nematodes identified as L3 Strongyluris sp. were found in the mantle cavity of 87 snails from Puerto Iguazú City (Prevalence 23 %; Mean Intensity= 34; Mean Abundance= 8. The shell size correlated with prevalence, mean intensity and mean abundance (p < 0.05 indicating that there is an exposure-infection constant rather than an accidental one. In other hand, the absence of infection in the smallest shell size suggests a threshold of size to be infected. Taking into account that there exist records of A. fulica infected by nematodes of medical and veterinary importance such as Angiostrongylus and Aelurostrongylus in some Brazilian states near Puerto Iguazú, we emphasize the need for snail surveillance.

Top 10 plant-parasitic nematodes in molecular plant pathology.

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Jones, John T; Haegeman, Annelies; Danchin, Etienne G J; Gaur, Hari S; Helder, Johannes; Jones, Michael G K; Kikuchi, Taisei; Manzanilla-López, Rosa; Palomares-Rius, Juan E; Wesemael, Wim M L; Perry, Roland N

2013-12-01

The aim of this review was to undertake a survey of researchers working with plant-parasitic nematodes in order to determine a 'top 10' list of these pathogens based on scientific and economic importance. Any such list will not be definitive as economic importance will vary depending on the region of the world in which a researcher is based. However, care was taken to include researchers from as many parts of the world as possible when carrying out the survey. The top 10 list emerging from the survey is composed of: (1) root-knot nematodes (Meloidogyne spp.); (2) cyst nematodes (Heterodera and Globodera spp.); (3) root lesion nematodes (Pratylenchus spp.); (4) the burrowing nematode Radopholus similis; (5) Ditylenchus dipsaci; (6) the pine wilt nematode Bursaphelenchus xylophilus; (7) the reniform nematode Rotylenchulus reniformis; (8) Xiphinema index (the only virus vector nematode to make the list); (9) Nacobbus aberrans; and (10) Aphelenchoides besseyi. The biology of each nematode (or nematode group) is reviewed briefly. © 2013 BSPP AND JOHN WILEY & SONS LTD.

Heterodera schachtii Tyrosinase-like protein a novel nematode effector modulating plant hormone homeostasis

Czech Academy of Sciences Publication Activity Database

Habash, S.; Radakovic, Z.S.; Vaňková, Radomíra; Siddique, S.; Dobrev, Petre; Gleason, C.; Grundler, F.M.W.; Elashry, A.

2017-01-01

Roč. 7, JUL 31 (2017), č. článku 6874. ISSN 2045-2322 Institutional support: RVO:61389030 Keywords : arabidopsis-thaliana * cyst-nematode * parasitic nematode * transient expression * host plants * sequence * identification * infection * model * transformation Subject RIV: ED - Physiology OBOR OECD: Plant sciences, botany Impact factor: 4.259, year: 2016

A northward colonisation of the Andes by the potato cyst nematode during geological times suggests multiple host-shifts from wild to cultivated potatoes.

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Picard, Damien; Sempere, Thierry; Plantard, Olivier

2007-02-01

The cyst nematode Globodera pallida is a major pest of potato in South America where this specialist parasite is native. To investigate its phylogeography, we have genotyped individuals from 42 Peruvian populations using mitochondrial and nuclear molecular markers. A clear south-to-north phylogeographical pattern was revealed with five well-supported clades. The clade containing the southern populations is genetically more diverse and forms the most basal branch. The large divergence among cytochrome b haplotypes suggests that they diverged before human domestication of potato. As the nematodes studied have been sampled on cultivated potato, multiple host-shifts from wild to cultivated potatoes must have occurred independently in each clade. We hypothesise that this south-to-north pattern took place during the uplift of the Andes beginning 20 My ago and following the same direction. To our knowledge, this is the first study of a plant parasite sampled on cultivated plants revealing an ancient phylogeographical pattern.

Molecular and Pathotype Identification of Potato Cyst Nematodes

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Mulyadi Mulyadi

2014-07-01

Full Text Available In Indonesia, potato cyst nematode (PCN was first reported in Bumiaji, Kota Batu, East Java by PT Syngenta and was identified as Globodera rostochiensis. Based on the surveillances, G. rostochiensis were also found in Batur, Banjarnegara, and Kejajar, Wonosobo, and Pangalengan, Bandung. In addition, in Batur, Banjarnegara, another species which was identified as G. pallida was found. The aim of this research were to identify the species of PCN using molecular method, pathotype identification, and to study the distributions of PCN especially in Java. The PCN are collected from potato planting areas in Kota Batu, East Java; Wonosobo and Banjarnegara, Central Java; and Pangalengan, Bandung, West Java. PCN were extracted and isolated from soil, and then identified by  morphological and molecular analysis. PCN were found in potato planting areas in Kota Batu, East Java; Wonosobo and Banjarnegara, Central Java; and Pangalengan, West Java. Based on the morphological characters, molecular method, and the differential host test, the PCN identified as G. rostochiensis are amplified an approximately 434 bp with pathotype Ro2.   Di Indonesia, nematoda sista kentang (NSK pertama dilaporkan di Bumiaji, Kota Batu, Jawa Timur oleh PT Syngenta yang diidentifikasi sebagai Globodera rostochiensis. Berdasarkan hasil survei, NSK ditemukan di Batur, Banjarnegara dan Kejajar, Wonosobo, Pangalengan. Spesies G. pallida juga ditemukan Batur, Banjarnegara. Penelitian ini bertujuan untuk mengidentifikasi spesies NSK menggunakan metode molekuler, identifikasi patotipe NSK, dan untuk mengetahui penyebaran NSK khususnya di Pulau Jawa. Sampel NSK dikumpulkan dari lahan pertanaman kentang di Bumiaji, Kota Batu, Jawa Timur; Wonosobo dan Banjarnegara, Jawa Tengah; serta Pangalengan, Bandung, Jawa Tengah. NSK diekstraksi dan diisolasi dari tanah yang selanjutnya diidentifikasi secara morfologi dan analisis molekuler. NSK yang terdapat pada lahan pertanaman kentang ditemukan di

Caracterização molecular de populações do nematóide-de-cisto-da-soja com diferentes índices de parasitismo na cultivar Hartwig Molecular characterization of soybean cyst nematode populations with different parasitism index to the Hartwig cultivar

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Ricardo Vilela Abdelnoor

2001-02-01

Full Text Available Recentemente, foi descoberta uma raça do nematóide-de-cisto-da-soja (NCS; Heterodera glycines que apresentou a capacidade de quebrar a resistência da cultivar Hartwig, até então considerada resistente a todas as raças conhecidas do nematóide. Essa população foi coletada no Município de Sorriso, Estado do Mato Grosso, e foi caracterizada como raça 4. Para verificar a diversidade genética entre esta e outras populações pertencentes às raças 4 e 9, foi feita uma caracterização molecular pela técnica de marcadores moleculares RAPD. Foram utilizadas nove populações do NCS, das quais quatro apresentavam a capacidade de parasitar 'Hartwig'. Foi verificado que as populações capazes de parasitar 'Hartwig' foram bastante diferentes das demais. Por meio de análise de agrupamento, com base nas distâncias genéticas encontradas, foram obtidos três grupos: o primeiro, constituído por indivíduos classificados como raça 4, mas que não parasitam 'Hartwig'; o segundo, constituído por quatro populações capazes de parasitar 'Hartwig', e o terceiro, por apenas uma população, classificado como raça 9, e que também não parasita 'Hartwig'. Este estudo confirmou que a população de NCS, encontrada em Sorriso, é geneticamente distinta das demais populações da raça 4 encontradas e constitui uma nova raça, denominada 4+.Recently, a new race of soybean cyst nematode (SCN (Heterodera glycines was discovered, which breaks the resistance of cultivar Hartwig, resistant to all known races of SCN. This population was obtained from soybean plants collected in the Sorriso county, state of Mato Grosso, Brazil, and is characterized as race 4. To verify if this isolate was different from others classified as races 4 and 9, their genetic diversity was analyzed by using the RAPD technique. Nine populations of SCN were analyzed, and only four populations were able to parasitize soybean plants cultivar Hartwig. Based on this study, it was

A Comparative Study of Four Methods for the Detection of Nematode Eggs and Large Protozoan Cysts in Mandrill Faecal Material.

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Pouillevet, Hanae; Dibakou, Serge-Ely; Ngoubangoye, Barthélémy; Poirotte, Clémence; Charpentier, Marie J E

2017-01-01

Coproscopical methods like sedimentation and flotation techniques are widely used in the field for studying simian gastrointestinal parasites. Four parasites of known zoonotic potential were studied in a free-ranging, non-provisioned population of mandrills (Mandrillus sphinx): 2 nematodes (Necatoramericanus/Oesophagostomum sp. complex and Strongyloides sp.) and 2 protozoan species (Balantidium coli and Entamoeba coli). Different coproscopical techniques are available but they are rarely compared to evaluate their efficiency to retrieve parasites. In this study 4 different field-friendly methods were compared. A sedimentation method and 3 different McMaster methods (using sugar, salt, and zinc sulphate solutions) were performed on 47 faecal samples collected from different individuals of both sexes and all ages. First, we show that McMaster flotation methods are appropriate to detect and thus quantify large protozoan cysts. Second, zinc sulphate McMaster flotation allows the retrieval of a higher number of parasite taxa compared to the other 3 methods. This method further shows the highest probability to detect each of the studied parasite taxa. Altogether our results show that zinc sulphate McMaster flotation appears to be the best technique to use when studying nematodes and large protozoa. © 2017 S. Karger AG, Basel.

Effective delivery of a nematode-repellent peptide using a root-cap-specific promoter.

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Lilley, Catherine J; Wang, Dong; Atkinson, Howard J; Urwin, Peter E

2011-02-01

The potential of the MDK4-20 promoter of Arabidopsis thaliana to direct effective transgenic expression of a secreted nematode-repellent peptide was investigated. Its expression pattern was studied in both transgenic Arabidopsis and Solanum tuberosum (potato) plants. It directed root-specific β-glucuronidase expression in both species that was chiefly localized to cells of the root cap. Use of the fluorescent timer protein dsRED-E5 established that the MDK4-20 promoter remains active for longer than the commonly used constitutive promoter CaMV35S in separated potato root border cells. Transgenic Arabidopsis lines that expressed the nematode-repellent peptide under the control of either AtMDK4-20 or CaMV35S reduced the establishment of the beet cyst nematode Heterodera schachtii. The best line using the AtMDK4-20 promoter displayed a level of resistance >80%, comparable to that of lines using the CaMV35S promoter. In transgenic potato plants, 94.9 ± 0.8% resistance to the potato cyst nematode Globodera pallida was achieved using the AtMDK4-20 promoter, compared with 34.4 ± 8.4% resistance displayed by a line expressing the repellent peptide from the CaMV35S promoter. These results establish the potential of the AtMDK4-20 promoter to limit expression of a repellent peptide whilst maintaining or even improving the efficacy of the cyst-nematode defence. © 2010 The Authors. Plant Biotechnology Journal © 2010 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

Morphological, biochemical, and molecular characterization of Meloidogyne spp. populations from Brazilian soybean production regions

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Camilla Martins de Oliveira

Full Text Available ABSTRACT: Soybean is a commodity of great economic importance worldwide, particularly in Brazil, world’s second largest producer. Nematodes, especially those of the Meloidogyne genus, severely limit productivity. Identification of nematode species is important for effective soybean management. Here, 26 populations of root-knot nematode (Meloidogyne spp. from 15 municipalities in the states of Bahia, Mato Grosso, Goias, and Minas Gerais were characterized based on the morphology of the female perineal region, esterase profile, and identification based on amplification of specific regions of the population genome. Among the Meloidogyne spp. populations obtained, M. incognita and M. javanica, were identified. No mixed populations were present in the samples. Diagnosis based on molecular analysis was shown to be reliable and the fastest for characterization of nematode populations compared to other methods analyzed.

Transcriptional profiling of root-knot nematode induced feeding sites in cowpea (Vigna unguiculata L. Walp. using a soybean genome array

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Das Sayan

2010-08-01

Full Text Available Abstract Background The locus Rk confers resistance against several species of root-knot nematodes (Meloidogyne spp., RKN in cowpea (Vigna unguiculata. Based on histological and reactive oxygen species (ROS profiles, Rk confers a delayed but strong resistance mechanism without a hypersensitive reaction-mediated cell death process, which allows nematode development but blocks reproduction. Results Responses to M. incognita infection in roots of resistant genotype CB46 and a susceptible near-isogenic line (null-Rk were investigated using a soybean Affymetrix GeneChip expression array at 3 and 9 days post-inoculation (dpi. At 9 dpi 552 genes were differentially expressed in incompatible interactions (infected resistant tissue compared with non-infected resistant tissue and 1,060 genes were differentially expressed in compatible interactions (infected susceptible tissue compared with non-infected susceptible tissue. At 3 dpi the differentially expressed genes were 746 for the incompatible and 623 for the compatible interactions. When expression between infected resistant and susceptible genotypes was compared, 638 and 197 genes were differentially expressed at 9 and 3 dpi, respectively. Conclusions In comparing the differentially expressed genes in response to nematode infection, a greater number and proportion of genes were down-regulated in the resistant than in the susceptible genotype, whereas more genes were up-regulated in the susceptible than in the resistant genotype. Gene ontology based functional categorization revealed that the typical defense response was partially suppressed in resistant roots, even at 9 dpi, allowing nematode juvenile development. Differences in ROS concentrations, induction of toxins and other defense related genes seem to play a role in this unique resistance mechanism.

Plant actin cytoskeleton re-modeling by plant parasitic nematodes.

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Engler, Janice de Almeida; Rodiuc, Natalia; Smertenko, Andrei; Abad, Pierre

2010-03-01

The cytoskeleton is an important component of the plant's defense mechanism against the attack of pathogenic organisms. Plants however, are defenseless against parasitic root-knot and cyst nematodes and respond to the invasion by the development of a special feeding site that supplies the parasite with nutrients required for the completion of its life cycle. Recent studies of nematode invasion under treatment with cytoskeletal drugs and in mutant plants where normal functions of the cytoskeleton have been affected, demonstrate the importance of the cytoskeleton in the establishment of a feeding site and successful nematode reproduction. It appears that in the case of microfilaments, nematodes hijack the intracellular machinery that regulates actin dynamics and modulate the organization and properties of the actin filament network. Intervening with this process reduces the nematode infection efficiency and inhibits its life cycle. This discovery uncovers a new pathway that can be exploited for the protection of plants against nematodes.

Dispersal of potato cyst nematodes measured using historical and spatial statistical analyses.

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Banks, N C; Hodda, M; Singh, S K; Matveeva, E M

2012-06-01

Rates and modes of dispersal of potato cyst nematodes (PCNs) were investigated. Analysis of records from eight countries suggested that PCNs spread a mean distance of 5.3 km/year radially from the site of first detection, and spread 212 km over ≈40 years before detection. Data from four countries with more detailed histories of invasion were analyzed further, using distance from first detection, distance from previous detection, distance from nearest detection, straight line distance, and road distance. Linear distance from first detection was significantly related to the time since the first detection. Estimated rate of spread was 5.7 km/year, and did not differ statistically between countries. Time between the first detection and estimated introduction date varied between 0 and 20 years, and differed among countries. Road distances from nearest and first detection were statistically significantly related to time, and gave slightly higher estimates for rate of spread of 6.0 and 7.9 km/year, respectively. These results indicate that the original site of introduction of PCNs may act as a source for subsequent spread and that this may occur at a relatively constant rate over time regardless of whether this distance is measured by road or by a straight line. The implications of this constant radial rate of dispersal for biosecurity and pest management are discussed, along with the effects of control strategies.

A synthetic peptide shows retro- and anterograde neuronal transport before disrupting the chemosensation of plant-pathogenic nematodes.

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Dong Wang

2011-03-01

Full Text Available Cyst nematodes are a group of plant pathogens each with a defined host range that cause major losses to crops including potato, soybean and sugar beet. The infective mobile stage hatches from dormant eggs and moves a short distance through the soil to plant roots, which it then invades. A novel strategy for control has recently been proposed in which the plant is able to secrete a peptide which disorientates the infective stage and prevents invasion of the pathogen. This study provides indirect evidence to support the mechanism by which one such peptide disrupts chemosensory function in nematodes. The peptide is a disulphide-constrained 7-mer with the amino acid sequence CTTMHPRLC that binds to nicotinic acetylcholine receptors. A fluorescently tagged version of this peptide with both epifluorescent and confocal microscopy was used to demonstrate that retrograde transport occurs from an aqueous environment along bare-ending primary cilia of chemoreceptive sensilla. The peptide is transported to the cell bodies of these neurons and on to a limited number of other neurons to which they connect. It appears to be localised in both neuronal processes and organelles adjacent to nuclei of some neurons suggesting it could be transported through the Golgi apparatus. The peptide takes 2.5 h to reach the neuronal cell bodies. Comparative studies established that similar but less abundant uptake occurs for Caenorhabditis elegans along its well studied dye-filling chemoreceptive neurons. Incubation in peptide solution or root-exudate from transgenic plants that secrete the peptide disrupted normal orientation of infective cyst nematodes to host root diffusate. The peptide probably undergoes transport along the dye-filling non-cholinergic chemoreceptive neurons to their synapses where it is taken up by the interneurons to which they connect. Coordinated responses to chemoreception are disrupted when the sub-set of cholinergic interneurons secrete the peptide

A synthetic peptide shows retro- and anterograde neuronal transport before disrupting the chemosensation of plant-pathogenic nematodes.

Science.gov (United States)

Wang, Dong; Jones, Laura M; Urwin, Peter E; Atkinson, Howard J

2011-03-07

Cyst nematodes are a group of plant pathogens each with a defined host range that cause major losses to crops including potato, soybean and sugar beet. The infective mobile stage hatches from dormant eggs and moves a short distance through the soil to plant roots, which it then invades. A novel strategy for control has recently been proposed in which the plant is able to secrete a peptide which disorientates the infective stage and prevents invasion of the pathogen. This study provides indirect evidence to support the mechanism by which one such peptide disrupts chemosensory function in nematodes. The peptide is a disulphide-constrained 7-mer with the amino acid sequence CTTMHPRLC that binds to nicotinic acetylcholine receptors. A fluorescently tagged version of this peptide with both epifluorescent and confocal microscopy was used to demonstrate that retrograde transport occurs from an aqueous environment along bare-ending primary cilia of chemoreceptive sensilla. The peptide is transported to the cell bodies of these neurons and on to a limited number of other neurons to which they connect. It appears to be localised in both neuronal processes and organelles adjacent to nuclei of some neurons suggesting it could be transported through the Golgi apparatus. The peptide takes 2.5 h to reach the neuronal cell bodies. Comparative studies established that similar but less abundant uptake occurs for Caenorhabditis elegans along its well studied dye-filling chemoreceptive neurons. Incubation in peptide solution or root-exudate from transgenic plants that secrete the peptide disrupted normal orientation of infective cyst nematodes to host root diffusate. The peptide probably undergoes transport along the dye-filling non-cholinergic chemoreceptive neurons to their synapses where it is taken up by the interneurons to which they connect. Coordinated responses to chemoreception are disrupted when the sub-set of cholinergic interneurons secrete the peptide at synapses that

Two simple methods for the collection of individual life stages of reniform nematode, Rotylenchulus reniformis

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The sedentary semi-endoparasitic nematode Rotylenchulus reniformis, the reniform nematode, is a serious pest of cotton and soybean in the United States. In recent years, interest in the molecular biology of the interaction between R. reniformis and its plant hosts has increased; however, the unusual...

Nematode neuropeptides as transgenic nematicides.

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Neil D Warnock

2017-02-01

Full Text Available Plant parasitic nematodes (PPNs seriously threaten global food security. Conventionally an integrated approach to PPN management has relied heavily on carbamate, organophosphate and fumigant nematicides which are now being withdrawn over environmental health and safety concerns. This progressive withdrawal has left a significant shortcoming in our ability to manage these economically important parasites, and highlights the need for novel and robust control methods. Nematodes can assimilate exogenous peptides through retrograde transport along the chemosensory amphid neurons. Peptides can accumulate within cells of the central nerve ring and can elicit physiological effects when released to interact with receptors on adjoining cells. We have profiled bioactive neuropeptides from the neuropeptide-like protein (NLP family of PPNs as novel nematicides, and have identified numerous discrete NLPs that negatively impact chemosensation, host invasion and stylet thrusting of the root knot nematode Meloidogyne incognita and the potato cyst nematode Globodera pallida. Transgenic secretion of these peptides from the rhizobacterium, Bacillus subtilis, and the terrestrial microalgae Chlamydomonas reinhardtii reduce tomato infection levels by up to 90% when compared with controls. These data pave the way for the exploitation of nematode neuropeptides as a novel class of plant protective nematicide, using novel non-food transgenic delivery systems which could be deployed on farmer-preferred cultivars.

A real-time PCR assay for the detection of Pasteuria nishizawae in soil

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Pasteuria nishizawae is a mycelial, endospore-forming, and obligately parasitic bacterium that has shown a great potential for the biological control of the soybean cyst nematode, Heterodera glycines, in both microplot and field studies. Other than China, Japan, and South Korea, P. nishizawae has be...

Dual roles for the variable domain in protein trafficking and host-specific recognition of Heterodera glycines CLE effector proteins

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Soybean cyst nematodes (Heterodera glycines) produce secreted effector proteins that function as peptide mimics of plant CLAVATA3 / ESR (CLE)-like peptides probably involved in the developmental reprogramming of root cells to form specialized feeding cells called syncytia. The site of action and me...

Invasive Species - A Threat to the Homeland?

Science.gov (United States)

2003-04-07

species of weeds, diseases and organisms on both my farm and the surrounding woodlands. Some of these species include soybean cyst nematode, soybean aphid ...natural enemies in their new environment. Parasites, pathogens , or predators that would inhibit or limit their spread are few or non-existent. In...tested, and fielded to control the genetically modified organism. Serums would be less effective, and diagnosis of human pathogens could change and

PsMPK7, a stress-associated mitogen-activated protein kinase (MAPK) in Phytophthora sojae, is required for stress tolerance, reactive oxygenated species detoxification, cyst germination, sexual reproduction and infection of soybean.

Science.gov (United States)

Gao, Jian; Cao, Mingna; Ye, Wenwu; Li, Haiyang; Kong, Liang; Zheng, Xiaobo; Wang, Yuanchao

2015-01-01

The sensing of stress signals and their transduction into appropriate responses are crucial for the adaptation, survival and infection of phytopathogenic fungi and oomycetes. Amongst evolutionarily conserved pathways, mitogen-activated protein kinase (MAPK) cascades function as key signal transducers that use phosphorylation to convey information. In this study, we identified a gene, designated PsMPK7, one of 14 predicted genes encoding MAPKs in Phytophthora sojae. PsMPK7 was highly transcribed in each tested stage, but was up-regulated in the zoospore, cyst and cyst germination stages. Silencing of PsMPK7 affected the growth of germinated cysts, oospore production and the pathogenicity of soybean. PsMPK7 transcription was induced by stresses from sorbitol, NaCl and hydrogen peroxide. Transformants in which PsMPK7 expression was silenced (PsMPK7-silenced) were significantly more sensitive to osmotic and oxidative stress. Aniline blue and diaminobenzidine staining revealed that the silenced lines did not suppress the host reactive oxygen species (ROS) burst, indicating that either the inoculated plants activated stronger defence responses to the transformants and/or the PsMPK7-silenced transformants failed to overcome plant defences. In addition, extracellular secretion of laccase decreased in the silenced lines. Overall, our results indicate that the PsMPK7 gene encodes a stress-associated MAPK in P. sojae that is important not only for responses to various stresses, but also for ROS detoxification, cyst germination, sexual oospore production and infection of soybean. © 2014 BSPP AND JOHN WILEY & SONS LTD.

Distinguishing Heterodera filipjevi and H. avenae using polymerase chain reaction-restriction fragment length polymorphism and cyst morphology.

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Yan, Guiping; Smiley, Richard W

2010-03-01

The cereal cyst nematodes Heterodera filipjevi and H. avenae impede wheat production in the Pacific Northwest (PNW). Accurate identification of cyst nematode species and awareness of high population density in affected fields are essential for designing effective control measures. Morphological methods for differentiating these species are laborious. These species were differentiated using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) of internal transcribed spacer (ITS)-ribosomal (r)DNA with up to six restriction endonucleases (TaqI, HinfI, PstI, HaeIII, RsaI, and AluI). The method was validated by inspecting underbridge structures of cyst vulval cones. Grid soil sampling of an Oregon field infested by both species revealed that H. filipjevi was present at most of the infested grid sites but mixtures of H. avenae and H. filipjevi also occurred. These procedures also detected and differentiated H. filipjevi and H. avenae in soil samples from nearby fields in Oregon and H. avenae in samples from Idaho and Washington. Intraspecific polymorphism was not observed within H. filipjevi or PNW H. avenae populations based on the ITS-rDNA. However, intraspecific variation was observed between H. avenae populations occurring in the PNW and France. Methods described here will improve detection and identification efficiencies for cereal cyst nematodes in wheat fields.

Influence of Maize Rotations on the Yield of Soybean Grown in Meloidogyne incognita Infested Soil

OpenAIRE

Kinloch, Robert A.

1983-01-01

A replicated field study was conducted from 1972 to 1980 involving soybeans grown in 2-, 3-, and 4-year rotations with maize in soil infested with Meloidogyne incognita. Monocultured soybeans were maintained as controls. Cropping regimes involved root-knot nematode susceptible and resistant soybean cultivars and soybeans treated and not treated with nematicides. Yields of susceptible cultivars declined with reduced length of rotation. Nematicide treatment significantly increased yields of sus...

A parasitic nematode releases cytokinin that controls cell division and orchestrates feeding site formation in host plants.

Science.gov (United States)

Siddique, Shahid; Radakovic, Zoran S; De La Torre, Carola M; Chronis, Demosthenis; Novák, Ondřej; Ramireddy, Eswarayya; Holbein, Julia; Matera, Christiane; Hütten, Marion; Gutbrod, Philipp; Anjam, Muhammad Shahzad; Rozanska, Elzbieta; Habash, Samer; Elashry, Abdelnaser; Sobczak, Miroslaw; Kakimoto, Tatsuo; Strnad, Miroslav; Schmülling, Thomas; Mitchum, Melissa G; Grundler, Florian M W

2015-10-13

Sedentary plant-parasitic cyst nematodes are biotrophs that cause significant losses in agriculture. Parasitism is based on modifications of host root cells that lead to the formation of a hypermetabolic feeding site (a syncytium) from which nematodes withdraw nutrients. The host cell cycle is activated in an initial cell selected by the nematode for feeding, followed by activation of neighboring cells and subsequent expansion of feeding site through fusion of hundreds of cells. It is generally assumed that nematodes manipulate production and signaling of the plant hormone cytokinin to activate cell division. In fact, nematodes have been shown to produce cytokinin in vitro; however, whether the hormone is secreted into host plants and plays a role in parasitism remained unknown. Here, we analyzed the spatiotemporal activation of cytokinin signaling during interaction between the cyst nematode, Heterodera schachtii, and Arabidopsis using cytokinin-responsive promoter:reporter lines. Our results showed that cytokinin signaling is activated not only in the syncytium but also in neighboring cells to be incorporated into syncytium. An analysis of nematode infection on mutants that are deficient in cytokinin or cytokinin signaling revealed a significant decrease in susceptibility of these plants to nematodes. Further, we identified a cytokinin-synthesizing isopentenyltransferase gene in H. schachtii and show that silencing of this gene in nematodes leads to a significant decrease in virulence due to a reduced expansion of feeding sites. Our findings demonstrate the ability of a plant-parasitic nematode to synthesize a functional plant hormone to manipulate the host system and establish a long-term parasitic interaction.

Transgenic Strategies for Enhancement of Nematode Resistance in Plants

Directory of Open Access Journals (Sweden)

Muhammad A. Ali

2017-05-01

Full Text Available Plant parasitic nematodes (PPNs are obligate biotrophic parasites causing serious damage and reduction in crop yields. Several economically important genera parasitize various crop plants. The root-knot, root lesion, and cyst nematodes are the three most economically damaging genera of PPNs on crops within the family Heteroderidae. It is very important to devise various management strategies against PPNs in economically important crop plants. Genetic engineering has proven a promising tool for the development of biotic and abiotic stress tolerance in crop plants. Additionally, the genetic engineering leading to transgenic plants harboring nematode resistance genes has demonstrated its significance in the field of plant nematology. Here, we have discussed the use of genetic engineering for the development of nematode resistance in plants. This review article also provides a detailed account of transgenic strategies for the resistance against PPNs. The strategies include natural resistance genes, cloning of proteinase inhibitor coding genes, anti-nematodal proteins and use of RNA interference to suppress nematode effectors. Furthermore, the manipulation of expression levels of genes induced and suppressed by nematodes has also been suggested as an innovative approach for inducing nematode resistance in plants. The information in this article will provide an array of possibilities to engineer resistance against PPNs in different crop plants.

Lipopolysaccharides of Rhizobium etli strain G12 act in potato roots as an inducing agent of systemic resistance to infection by the cyst nematode Globodera pallida.

Science.gov (United States)

Reitz, M; Rudolph, K; Schröder, I; Hoffmann-Hergarten, S; Hallmann, J; Sikora, R A

2000-08-01

Recent studies have shown that living and heat-killed cells of the rhizobacterium Rhizobium etli strain G12 induce in potato roots systemic resistance to infection by the potato cyst nematode Globodera pallida. To better understand the mechanisms of induced resistance, we focused on identifying the inducing agent. Since heat-stable bacterial surface carbohydrates such as exopolysaccharides (EPS) and lipopolysaccharides (LPS) are essential for recognition in the symbiotic interaction between Rhizobium and legumes, their role in the R. etli-potato interaction was studied. EPS and LPS were extracted from bacterial cultures, applied to potato roots, and tested for activity as an inducer of plant resistance to the plant-parasitic nematode. Whereas EPS did not affect G. pallida infection, LPS reduced nematode infection significantly in concentrations as low as 1 and 0.1 mg ml(-1). Split-root experiments, guaranteeing a spatial separation of inducing agent and challenging pathogen, showed that soil treatments of one half of the root system with LPS resulted in a highly significant (up to 37%) systemic induced reduction of G. pallida infection of potato roots in the other half. The results clearly showed that LPS of R. etli G12 act as the inducing agent of systemic resistance in potato roots.

Nitrogen credits from cowpea, soybean, groundnut and Mucuna to

African Journals Online (AJOL)

komla

fixing capacity. A field study was conducted in 1999 and 2000 at Ejura in the forest savanna transition ..... plants. Soybean, cowpea, and groundnut could be susceptible to various root knot nematode ..... Maize and legumes production guide.

Using SNP markers to dissect linkage disequilibrium at a major quantitative trait locus for resistance to the potato cyst nematode Globodera pallida on potato chromosome V.

Science.gov (United States)

Achenbach, Ute; Paulo, Joao; Ilarionova, Evgenyia; Lübeck, Jens; Strahwald, Josef; Tacke, Eckhard; Hofferbert, Hans-Reinhard; Gebhardt, Christiane

2009-02-01

The damage caused by the parasitic root cyst nematode Globodera pallida is a major yield-limiting factor in potato cultivation . Breeding for resistance is facilitated by the PCR-based marker 'HC', which is diagnostic for an allele conferring high resistance against G. pallida pathotype Pa2/3 that has been introgressed from the wild potato species Solanum vernei into the Solanum tuberosum tetraploid breeding pool. The major quantitative trait locus (QTL) controlling this nematode resistance maps on potato chromosome V in a hot spot for resistance to various pathogens including nematodes and the oomycete Phytophthora infestans. An unstructured sample of 79 tetraploid, highly heterozygous varieties and breeding clones was selected based on presence (41 genotypes) or absence (38 genotypes) of the HC marker. Testing the clones for resistance to G. pallida confirmed the diagnostic power of the HC marker. The 79 individuals were genotyped for 100 single nucleotide polymorphisms (SNPs) at 10 loci distributed over 38 cM on chromosome V. Forty-five SNPs at six loci spanning 2 cM in the interval between markers GP21-GP179 were associated with resistance to G. pallida. Based on linkage disequilibrium (LD) between SNP markers, six LD groups comprising between 2 and 18 SNPs were identified. The LD groups indicated the existence of multiple alleles at a single resistance locus or at several, physically linked resistance loci. LD group C comprising 18 SNPs corresponded to the 'HC' marker. LD group E included 16 SNPs and showed an association peak, which positioned one nematode resistance locus physically close to the R1 gene family.

Phenotypic analysis of apoplastic effectors from the phytopathogenic nematode, Globodera rostochiensis demonstrates that an expansin can induce and suppress host defenses

Science.gov (United States)

The potato cyst nematode Globodera rostochiensis (Woll.) is an important pest of potato. Like other biotrophic pathogens, plant parasitic nematodes are presumed to employ effector proteins, secreted into the apoplast as well as the host cytoplasm to successfully infect their hosts. We have identifie...

Molecular cloning of the potato Gro1-4 gene conferring resistance to pathotype Ro1 of the root cyst nematode Globodera rostochiensis, based on a candidate gene approach.

Science.gov (United States)

Paal, Jürgen; Henselewski, Heike; Muth, Jost; Meksem, Khalid; Menéndez, Cristina M; Salamini, Francesco; Ballvora, Agim; Gebhardt, Christiane

2004-04-01

The endoparasitic root cyst nematode Globodera rostochiensis causes considerable damage in potato cultivation. In the past, major genes for nematode resistance have been introgressed from related potato species into cultivars. Elucidating the molecular basis of resistance will contribute to the understanding of nematode-plant interactions and assist in breeding nematode-resistant cultivars. The Gro1 resistance locus to G. rostochiensis on potato chromosome VII co-localized with a resistance-gene-like (RGL) DNA marker. This marker was used to isolate from genomic libraries 15 members of a closely related candidate gene family. Analysis of inheritance, linkage mapping, and sequencing reduced the number of candidate genes to three. Complementation analysis by stable potato transformation showed that the gene Gro1-4 conferred resistance to G. rostochiensis pathotype Ro1. Gro1-4 encodes a protein of 1136 amino acids that contains Toll-interleukin 1 receptor (TIR), nucleotide-binding (NB), leucine-rich repeat (LRR) homology domains and a C-terminal domain with unknown function. The deduced Gro1-4 protein differed by 29 amino acid changes from susceptible members of the Gro1 gene family. Sequence characterization of 13 members of the Gro1 gene family revealed putative regulatory elements and a variable microsatellite in the promoter region, insertion of a retrotransposon-like element in the first intron, and a stop codon in the NB coding region of some genes. Sequence analysis of RT-PCR products showed that Gro1-4 is expressed, among other members of the family including putative pseudogenes, in non-infected roots of nematode-resistant plants. RT-PCR also demonstrated that members of the Gro1 gene family are expressed in most potato tissues.

Different responses of soybean cyst nematode resistance between ...

Indian Academy of Sciences (India)

2016-12-02

Dec 2, 2016 ... 3Crop Research Institute, Shandong Academy of Agricultural Sciences, Jinan, Shandong 250100, People's Republic of ... SCN race 1 (HG types 2.5.7), while 7605 is highly susceptible. ... nomical and environmental friendly method to control ..... analysis and qualitative mapping of a major partial-resistance.

Functional characterization of CLE peptides from a plant-parasitic nematode Globodera rostochiensis

Science.gov (United States)

Plant CLAVATA3/ESR (CLE) proteins are a large family of secreted peptide ligands that play important roles in plant growth and development. Recent evidence suggests that plant-parasitic cyst nematodes secrete ligand mimics of plant CLE peptides to modify selected host root cells into multinucleate f...

Population Genetics of Hirsutella rhossiliensis, a Dominant Parasite of Cyst Nematode Juveniles on a Continental Scale.

Science.gov (United States)

Wang, Niuniu; Zhang, Yongjie; Jiang, Xianzhi; Shu, Chi; Hamid, M Imran; Hussain, Muzammil; Chen, Senyu; Xu, Jianping; Xiang, Meichun; Liu, Xingzhong

2016-11-01

Hirsutella rhossiliensis is a parasite of juvenile nematodes, effective against a diversity of plant-parasitic nematodes. Its global distribution on various nematode hosts and its genetic variation for several geographic regions have been reported, while the global population genetic structure and factors underlying patterns of genetic variation of H. rhossiliensis are unclear. In this study, 87 H. rhossiliensis strains from five nematode species (Globodera sp., Criconemella xenoplax, Rotylenchus robustus, Heterodera schachtii, and Heterodera glycines) in Europe, the United States, and China were investigated by multilocus sequence analyses. A total of 280 variable sites (frequency, 0.6%) at eight loci and six clustering in high accordance with geographic populations or host nematode-associated populations were identified. Although H. rhossiliensis is currently recognized as an asexual fungus, recombination events were frequently detected. In addition, significant genetic isolation by geography and nematode hosts was revealed. Overall, our analyses showed that recombination, geographic isolation, and nematode host adaptation have played significant roles in the evolutionary history of H. rhossiliensis IMPORTANCE: H. rhossiliensis has great potential for use as a biocontrol agent to control nematodes in a sustainable manner as an endoparasitic fungus. Therefore, this study has important implications for the use of H. rhossiliensis as a biocontrol agent and provides interesting insights into the biology of this species. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Field evaluation of the nematicide fluensulfone for control of the potato cyst nematode Globodera pallida.

Science.gov (United States)

Norshie, Patrick M; Grove, Ivan G; Back, Matthew A

2016-10-01

Three field experiments evaluated the performance of the nematicide fluensulfone against the potato cyst nematode Globodera pallida in Shropshire, England. Experiments 1 and 2 showed reduced root infection and lowered multiplication of G. pallida following fluensulfone (Nimitz 15G(®) ) soil treatments at five rates (1.95, 3.00, 4.05 (full rate), 5.05 and 6.00 kg AI ha(-1) ) and Nimitz 480EC(®) at the full rate. Experiment 3 demonstrated a positive interaction between the full rate of Nimitz 15G and the potato variety Santé in the reduction of G. pallida. The fluensulfone treatments at the full rate had more consistent effects than the lower rates, and there were no greater effects for the treatments higher than this full rate. Generally, fluensulfone was less efficacious than oxamyl or fosthiazate, which suggests that the treatment may not be reliably integrated within shorter potato rotations. The data suggest that fluensulfone soil application could make a useful addition to the few available nematicide treatments for the control of G. pallida rather than be a substitute for these treatments.© 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Laboratory trials to infect insects and nematodes by some acaropathogenic Hirsutella strains (Mycota: Clavicipitaceous anamorphs).

Science.gov (United States)

Bałazy, Stanisław; Wrzosek, Marta; Sosnowska, Danuta; Tkaczuk, Cezary; Muszewska, Anna

2008-02-01

Laboratory assays have been carried out to artificially infect insect larvae of the birch bark-beetle (Scolytus ratzeburgi Jans.-Coleoptera, Scolytidae) and codling moth Cydia pomonella L. -Lepidoptera, Tortricidae) as well as the potato cyst nematode-Globodera rostochiensis Wollenweber, sugar beet nematode-Heterodera schachtii Schmidt and root-knot nematode-Meloidogyne hapla Chif (Nematoda, Heteroderidae), by the phialoconidia of some fungal species of the genus Hirsutella. From among four species tested on insects only H. nodulosa Petch infected about 20% of S. ratzeburgi larvae, whereas H. kirchneri (Rostrup) Minter, Brady et Hall, H. minnesotensis Chen, Liu et Chen, and H. rostrata Bałazy et Wiśniewski did not affect insect larvae. Only single eggs of the root-knot nematode were infected by H. minnesotensis in the laboratory trials, whereas its larvae remained unaffected. No infection cases of the potato cyst nematode (G. rostochiensis) and sugar beet nematode eggs were obtained. Comparisons of DNA-ITS-region sequences of the investigated strains with GenBank data showed no differences between H. minnesotensis isolates from the nematodes Heterodera glycines Ichinohe and from tarsonemid mites (authors' isolate). A fragment of ITS 2 with the sequence characteristic only for H. minnesotensis was selected. Two cluster analyses indicated close similarity of this species to H. thompsonii as sister clades, but the latter appeared more heterogenous. Insect and mite pathogenic species H. nodulosa localizes close to specialized aphid pathogen H. aphidis, whereas the phytophagous mite pathogens H. kirchneri and H. gregis form a separate sister clade. Hirsutella rostrata does not show remarkable relations to the establishment of aforementioned groups. Interrelated considerations on the morphology, biology and DNA sequencing of investigated Hirsutella species state their identification more precisely and facilitate the establishment of systematic positions.

An efficient cDNA-AFLP-based strategy for the identification of putative pathogenicity factors from the potato cyst nematode Globodera rostochiensis.

Science.gov (United States)

Qin, L; Overmars, H; Helder, J; Popeijus, H; van der Voort, J R; Groenink, W; van Koert, P; Schots, A; Bakker, J; Smant, G

2000-08-01

A new strategy has been designed to identify putative pathogenicity factors from the dorsal or subventral esophageal glands of the potato cyst nematode Globodera rostochiensis. Three independent criteria were used for selection. First, genes of interest should predominantly be expressed in infective second-stage juveniles, and not, or to a far lesser extent, in younger developmental stages. For this, gene expression profiles from five different developmental stages were generated with cDNA-AFLP (amplified fragment length polymorphism). Secondly, the mRNA corresponding to such a putative pathogenicity factor should predominantly be present in the esophageal glands of pre-parasitic juveniles. This was checked by in situ hybridization. As a third criterion, these proteinaceous factors should be preceded by a signal peptide for secretion. Expression profiles of more than 4,000 genes were generated and three up-regulated, dorsal gland-specific proteins preceded by signal peptide for secretion were identified. No dorsal gland genes have been cloned before from plant-parasitic nematodes. The partial sequence of these three factors, A4, A18, and A41, showed no significant homology to any known gene. Their presence in the dorsal glands of infective juveniles suggests that these proteins could be involved in feeding cell initiation, and not in migration in the plant root or in protection against plant defense responses. Finally, the applicability of this new strategy in other plant-microbe interactions is discussed.

Cereal Cyst Nematode (Heterodera avenae) on Oats. II. Early Root Development and Nematode Tolerance

OpenAIRE

Volkmar, K. M.

1989-01-01

The effect of Heterodera avenae infestation on early seminal and lateral root growth was examined in four oat genotypes differing in tolerance to H. avenae. Recently emerged seminal roots were inoculated with a range of H. avenae larval densities, then transferred a hydroponic system to remove the effect of later nematode penetration on root development. Intolerance to H. avenae was assessed in terms of impairment of seminal root extension resulting in fewer primary lateral roots emerging fro...

A high-resolution map of the Grp1 locus on chromosome V of potato harbouring broad-spectrum resistance to the cyst nematode species Globodera pallida and Globodera rostochiensis.

Science.gov (United States)

Finkers-Tomczak, Anna; Danan, Sarah; van Dijk, Thijs; Beyene, Amelework; Bouwman, Liesbeth; Overmars, Hein; van Eck, Herman; Goverse, Aska; Bakker, Jaap; Bakker, Erin

2009-06-01

The Grp1 locus confers broad-spectrum resistance to the potato cyst nematode species Globodera pallida and Globodera rostochiensis and is located in the GP21-GP179 interval on the short arm of chromosome V of potato. A high-resolution map has been developed using the diploid mapping population RHAM026, comprising 1,536 genotypes. The flanking markers GP21 and GP179 have been used to screen the 1,536 genotypes for recombination events. Interval mapping of the resistances to G. pallida Pa2 and G. rostochiensis Ro5 resulted in two nearly identical LOD graphs with the highest LOD score just north of marker TG432. Detailed analysis of the 44 recombinant genotypes showed that G. pallida and G. rostochiensis resistance could not be separated and map to the same location between marker SPUD838 and TG432. It is suggested that the quantitative resistance to both nematode species at the Grp1 locus is mediated by one or more tightly linked R genes that might belong to the NBS-LRR class.

Damage-associated responses of the host contribute to defence against cyst nematodes but not root-knot nematodes

NARCIS (Netherlands)

Shah, Syed Jehangir; Anjam, Muhammad Shahzad; Mendy, Badou; Anwer, Muhammad Arslan; Habash, Samer S.; Lozano-Torres, Jose L.; Grundler, Florian M.W.; Siddique, Shahid

2017-01-01

When nematodes invade and subsequently migrate within plant roots, they generate cell wall fragments (in the form of oligogalacturonides; OGs) that can act as damage-associated molecular patterns and activate host defence responses. However, the molecular mechanisms mediating damage responses in

Root-Knot and Cyst Nematodes Activate Procambium-Associated Genes in Arabidopsis Roots

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Yasuka L. Yamaguchi

2017-07-01

Full Text Available Developmental plasticity is one of the most striking features of plant morphogenesis, as plants are able to vary their shapes in response to environmental cues. Biotic or abiotic stimuli often promote organogenesis events in plants not observed under normal growth conditions. Root-knot nematodes (RKNs are known to parasitize multiple species of rooting plants and to induce characteristic tissue expansion called galls or root-knots on the roots of their hosts by perturbing the plant cellular machinery. Galls contain giant cells (GCs and neighboring cells, and the GCs are a source of nutrients for the parasitizing nematode. Highly active cell proliferation was observed in galls. However, the underlying mechanisms that regulate the symptoms triggered by the plant-nematode interaction have not yet been elucidated. In this study, we deciphered the molecular mechanism of gall formation with an in vitro infection assay system using RKN Meloidogyne incognita, and the model plant Arabidopsis thaliana. By taking advantages of this system, we performed next-generation sequencing-based transcriptome profiling, and found that the expression of procambium identity-associated genes were enriched during gall formation. Clustering analyses with artificial xylogenic systems, together with the results of expression analyses of the candidate genes, showed a significant correlation between the induction of gall cells and procambium-associated cells. Furthermore, the promoters of several procambial marker genes such as ATHB8, TDR and WOX4 were activated not only in M. incognita-induced galls, but similarly in M. javanica induced-galls and Heterodera schachtii-induced syncytia. Our findings suggest that phytoparasitic nematodes modulate the host’s developmental regulation of the vascular stem cells during gall formation.

Root-Knot and Cyst Nematodes Activate Procambium-Associated Genes in Arabidopsis Roots.

Science.gov (United States)

Yamaguchi, Yasuka L; Suzuki, Reira; Cabrera, Javier; Nakagami, Satoru; Sagara, Tomomi; Ejima, Chika; Sano, Ryosuke; Aoki, Yuichi; Olmo, Rocio; Kurata, Tetsuya; Obayashi, Takeshi; Demura, Taku; Ishida, Takashi; Escobar, Carolina; Sawa, Shinichiro

2017-01-01

Developmental plasticity is one of the most striking features of plant morphogenesis, as plants are able to vary their shapes in response to environmental cues. Biotic or abiotic stimuli often promote organogenesis events in plants not observed under normal growth conditions. Root-knot nematodes (RKNs) are known to parasitize multiple species of rooting plants and to induce characteristic tissue expansion called galls or root-knots on the roots of their hosts by perturbing the plant cellular machinery. Galls contain giant cells (GCs) and neighboring cells, and the GCs are a source of nutrients for the parasitizing nematode. Highly active cell proliferation was observed in galls. However, the underlying mechanisms that regulate the symptoms triggered by the plant-nematode interaction have not yet been elucidated. In this study, we deciphered the molecular mechanism of gall formation with an in vitro infection assay system using RKN Meloidogyne incognita , and the model plant Arabidopsis thaliana. By taking advantages of this system, we performed next-generation sequencing-based transcriptome profiling, and found that the expression of procambium identity-associated genes were enriched during gall formation. Clustering analyses with artificial xylogenic systems, together with the results of expression analyses of the candidate genes, showed a significant correlation between the induction of gall cells and procambium-associated cells. Furthermore, the promoters of several procambial marker genes such as ATHB8 , TDR and WOX4 were activated not only in M. incognita -induced galls, but similarly in M. javanica induced-galls and Heterodera schachtii -induced syncytia. Our findings suggest that phytoparasitic nematodes modulate the host's developmental regulation of the vascular stem cells during gall formation.

Comparative transcriptome analysis of two races of Heterodera glycines at different developmental stages.

Directory of Open Access Journals (Sweden)

Gaofeng Wang

Full Text Available The soybean cyst nematode, Heterodera glycines, is an important pest of soybeans. Although resistance is available against this nematode, selection for virulent races can occur, allowing the nematode to overcome the resistance of cultivars. There are abundant field populations, however, little is known about their genetic diversity. In order to elucidate the differences between races, we investigated the transcriptional diversity within race 3 and race 4 inbred lines during their compatible interactions with the soybean host Zhonghuang 13. Six different race-enriched cDNA libraries were constructed with limited nematode samples collected from the three sedentary stages, parasitic J2, J3 and J4 female, respectively. Among 689 putative race-enriched genes isolated from the six libraries with functional annotations, 92 were validated by quantitative RT-PCR (qRT-PCR, including eight putative effector encoding genes. Further race-enriched genes were validated within race 3 and race 4 during development in soybean roots. Gene Ontology (GO analysis of all the race-enriched genes at J3 and J4 female stages showed that most of them functioned in metabolic processes. Relative transcript level analysis of 13 selected race-enriched genes at four developmental stages showed that the differences in their expression abundance took place at either one or more developmental stages. This is the first investigation into the transcript diversity of H. glycines races throughout their sedentary stages, increasing the understanding of the genetic diversity of H. glycines.

Superoxide Dismutase as a Tool for the Mulacular Identification of Plant Parasitic Nematodes

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S. Molinari

2004-08-01

Full Text Available Superoxide dismutase (SOD is a constitutive family of enzymes produced by all aerobic organisms. Varying amounts of SOD activity have been found at all life stages of the most diffused plant parasitic nematodes. SOD is important to aerobic metabolism and parasitism of nematodes in that it catalyzes the first step of the neutralization of the highly toxic superoxide anion (O2 •-, which is largely produced in plant-nematode incompatible reactions. SOD has also been shown to be a significant tool to diagnose root-knot, cyst-, and longidorid nematodes. A high SOD polymorphism has been revealed by Native-Page on gradient polyacrylamide gels for Meloidogyne spp. and by isoelectrofocusing for Globodera, Xiphinema and Longidorus spp. The sensitivity of such procedures has been improved by using the PhastSystem (Amersham Biosciences, Piscata, NJ, USA, an automated equipment for electrophoresis. An accurate discrimination of species of all the nematode genera tested has been achieved and an attempt was made to group populations of the Xiphinema americanum-group and to detect Globodera rostochiensis and G. pallida pathotypes.

Transcription of Biotic Stress Associated Genes in White Clover (Trifolium repens L.) Differs in Response to Cyst and Root-Knot Nematode Infection.

Science.gov (United States)

Islam, Afsana; Mercer, Chris F; Leung, Susanna; Dijkwel, Paul P; McManus, Michael T

2015-01-01

The transcription of four members of the Kunitz proteinase inhibitor (KPI) gene family of white clover (Trifolium repens L.), designated as Tr-KPI1, Tr-KPI2, Tr-KPI4 and Tr-KPI5, was investigated at both local infection (roots) and systemic (leaf tissue) sites in white clover in response to infection with the clover root knot nematode (CRKN) Meloidogyne trifoliophila and the clover cyst nematode (CCN) Heterodera trifolii. Invasion by the CRKN resulted in a significant decrease in transcript abundance of Tr-KPI4 locally at both 4 days post-infection (dpi) and at 8 dpi, and an increase in transcription of Tr-KPI1 systemically at 8 dpi. In contrast, an increase in transcript abundance of all four Tr-KPI genes locally at 4 and 8 dpi, and an increase of Tr-KPI1, Tr-KPI2, and Tr-KPI5 at 8 dpi systemically was observed in response to infection with the CCN. Challenge of a resistant (R) genotype and a susceptible (S) genotype of white clover with the CCN revealed a significant increase in transcript abundance of all four Tr-KPI genes locally in the R genotype, while an increase in abundance of only Tr-KPI1, Tr-KPI2, and Tr-KPI5 was observed in the S genotype, and only at 4 dpi. The transcript abundance of a member of the1-AMINOCYCLOPROPANE-1-CARBOXYLATE (ACC) SYNTHASE gene family from white clover (Tr-ACS1) was significantly down-regulated locally in response to CRKN infection at 4 and 8 dpi and at 4 dpi, systemically, while abundance increased locally and systemically at 8 dpi in response to CCN challenge. Conversely, the abundance of the jasmonic acid (JA) signalling gene, CORONATINE-INSENSITIVE PROTEIN 1 from white clover (Tr-COI1) increased significantly at 8 dpi locally in response to CRKN infection, but decreased at 8 dpi in response to CCN infection. The significance of this differential regulation of transcription is discussed with respect to differences in infection strategy of the two nematode species.

Identification of vacuoles containing extraintestinal differentiated forms of Legionella pneumophila in colonized Caenorhabditis elegans soil nematodes.

Science.gov (United States)

Hellinga, Jacqueline R; Garduño, Rafael A; Kormish, Jay D; Tanner, Jennifer R; Khan, Deirdre; Buchko, Kristyn; Jimenez, Celine; Pinette, Mathieu M; Brassinga, Ann Karen C

2015-08-01

Legionella pneumophila, a causative agent of Legionnaires' disease, is a facultative intracellular parasite of freshwater protozoa. Legionella pneumophila features a unique developmental network that involves several developmental forms including the infectious cyst forms. Reservoirs of L. pneumophila include natural and man-made freshwater systems; however, recent studies have shown that isolates of L. pneumophila can also be obtained directly from garden potting soil suggesting the presence of an additional reservoir. A previous study employing the metazoan Caenorhabditis elegans, a member of the Rhabditidae family of free-living soil nematodes, demonstrated that the intestinal lumen can be colonized with L. pneumophila. While both replicative forms and differentiated forms were observed in C. elegans, these morphologically distinct forms were initially observed to be restricted to the intestinal lumen. Using live DIC imaging coupled with focused transmission electron microscopy analyses, we report here that L. pneumophila is able to invade and establish Legionella-containing vacuoles (LCVs) in the intestinal cells. In addition, LCVs containing replicative and differentiated cyst forms were observed in the pseudocoelomic cavity and gonadal tissue of nematodes colonized with L. pneumophila. Furthermore, establishment of LCVs in the gonadal tissue was Dot/Icm dependent and required the presence of the endocytic factor RME-1 to gain access to maturing oocytes. Our findings are novel as this is the first report, to our knowledge, of extraintestinal LCVs containing L. pneumophila cyst forms in C. elegans tissues, highlighting the potential of soil-dwelling nematodes as an alternate environmental reservoir for L. pneumophila. © 2015 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Detection and quantification of Plectosphaerella cucumerina, a potential biological control agent of potato cyst nematodes, by using conventional PCR, real-time PCR, selective media, and baiting.

Science.gov (United States)

Atkins, S D; Clark, I M; Sosnowska, D; Hirsch, P R; Kerry, B R

2003-08-01

Potato cyst nematodes (PCN) are serious pests in commercial potato production, causing yield losses valued at approximately $300 million in the European Community. The nematophagous fungus Plectosphaerella cucumerina has demonstrated its potential as a biological control agent against PCN populations by reducing field populations by up to 60% in trials. The use of biological control agents in the field requires the development of specific techniques to monitor the release, population size, spread or decline, and pathogenicity against its host. A range of methods have therefore been developed to monitor P. cucumerina. A species-specific PCR primer set (PcCF1-PcCR1) was designed that was able to detect the presence of P. cucumerina in soil, root, and nematode samples. PCR was combined with a bait method to identify P. cucumerina from infected nematode eggs, confirming the parasitic ability of the fungus. A selective medium was adapted to isolate the fungus from root and soil samples and was used to quantify the fungus from field sites. A second P. cucumerina-specific primer set (PcRTF1-PcRTR1) and a Taqman probe (PcRTP1) were designed for real-time PCR quantification of the fungus and provided a very sensitive means of detecting the fungus from soil. PCR, bait, and culture methods were combined to investigate the presence and abundance of P. cucumerina from two field sites in the United Kingdom where PCN populations were naturally declining. All methods enabled differences in the activity of P. cucumerina to be detected, and the results demonstrated the importance of using a combination of methods to investigate population size and activity of fungi.

Use of remote sensing, geographic information systems, and spatial statistics to assess spatio-temporal population dynamics of Heterodera glycines and soybean yield quantity and quality

Science.gov (United States)

Moreira, Antonio Jose De Araujo

Soybean, Glycine max (L.) Merr., is an important source of oil and protein worldwide, and soybean cyst nematode (SCN), Heterodera glycines, is among the most important yield-limiting factors in soybean production worldwide. Early detection of SCN is difficult because soybean plants infected by SCN often do not exhibit visible symptoms. It was hypothesized, however, that reflectance data obtained by remote sensing from soybean canopies may be used to detect plant stress caused by SCN infection. Moreover, reflectance measurements may be related to soybean growth and yield. Two field experiments were conducted from 2000 to 2002 to study the relationships among reflectance data, quantity and quality of soybean yield, and SCN population densities. The best relationships between reflectance and the quantity of soybean grain yield occurred when reflectance data were obtained late August to early September. Similarly, reflectance was best related to seed oil and seed protein content and seed size when measured during late August/early September. Grain quality-reflectance relationships varied spatially and temporally. Reflectance measured early or late in the season had the best relationships with SCN population densities measured at planting. Soil properties likely affected reflectance measurements obtained at the beginning of the season and somehow may have been related to SCN population densities at planting. Reflectance data obtained at the end of the growing season likely was affected by early senescence of SCN-infected soybeans. Spatio-temporal aspects of SCN population densities in both experiments were assessed using spatial statistics and regression analyses. In the 2000 and 2001 growing seasons, spring-to-fall changes in SCN population densities were best related to SCN population densities at planting for both experiments. However, within-season changes in SCN population densities were best related to SCN population densities at harvest for both experiments in

Microaspiration of esophageal gland cells and cDNA library construction for identifying parasitism genes of plant-parasitic nematodes.

Science.gov (United States)

Hussey, Richard S; Huang, Guozhong; Allen, Rex

2011-01-01

Identifying parasitism genes encoding proteins secreted from a plant-parasitic nematode's esophageal gland cells and injected through its stylet into plant tissue is the key to understanding the molecular basis of nematode parasitism of plants. Parasitism genes have been cloned by directly microaspirating the cytoplasm from the esophageal gland cells of different parasitic stages of cyst or root-knot nematodes to provide mRNA to create a gland cell-specific cDNA library by long-distance reverse-transcriptase polymerase chain reaction. cDNA clones are sequenced and deduced protein sequences with a signal peptide for secretion are identified for high-throughput in situ hybridization to confirm gland-specific expression.

Scientific Opinion on the risks to plant health posed by European versus non-European populations of the potato cyst nematodes Globodera pallida and Globodera rostochiensis

DEFF Research Database (Denmark)

Baker, R.; Candresse, T.; Dormannsné Simon, E.

2012-01-01

The Panel on Plant Health has delivered a scientific opinion on the different risks posed by European and non-European populations of the potato cyst nematodes (PCN) Globodera pallida and Globodera rostochiensis to solanaceous plants in the EU and on the effectiveness of current control measures...... to place of production freedom and soil origin were noted, and the Panel identified additional risk reduction options for certain plants for planting (e.g. bulbs) and additional requirements to confirm the absence of PCN in places of production. The Panel also identified some problems with the existing...... control measures to reduce the spread of PCN within the EU. A thorough and well-coordinated EU-wide survey using standardized methods would be necessary to evaluate the need to maintain these measures. The monitoring of PCN populations should exploit new diagnostic techniques (e.g. mitochondrial DNA...

Earthworms and Plant Residues Modify Nematodes in Tropical Cropping Soils (Madagascar): A Mesocosm Experiment

International Nuclear Information System (INIS)

Villenave, C.; Kichenin, E.; Djigal, D.; Blanchart, E.; Rabary, B.; Djigal, D.

2010-01-01

Free-living nematodes present several characteristics that have led to their use as bio indicators of soil quality. Analyzing the structure of nematofauna is a pertinent way to understand soil biological processes. Earthworms play an important role in soil biological functioning and organic matter dynamics. Their effects on soil nematofauna have seldom been studied. We studied the effect of the tropical endogeic earthworm, Pontoscolex corethrurus, on nematode community structure in a 5-month field mesocosm experiment conducted in Madagascar. Ten different treatments with or without earthworms and with or without organic residues (rice, soybean) were compared. Organic residues were applied on the soil surface or mixed with the soil. The abundance of nematodes (bacterial and fungal feeders) was higher in presence of P. corethrurus than in their absence. The type of plant residues as well as their localisation had significant effects on the abundance and composition of soil nematodes. The analysis of nematode community structure showed that earthworm activity led to an overall activation of the microbial compartment without specific stimulation of the bacterial or fungal compartment.

Earthworms and Plant Residues Modify Nematodes in Tropical Cropping Soils (Madagascar: A Mesocosm Experiment

Directory of Open Access Journals (Sweden)

Cécile Villenave

2010-01-01

Full Text Available Free-living nematodes present several characteristics that have led to their use as bioindicators of soil quality. Analyzing the structure of nematofauna is a pertinent way to understand soil biological processes. Earthworms play an important role in soil biological functioning and organic matter dynamics. Their effects on soil nematofauna have seldom been studied. We studied the effect of the tropical endogeic earthworm, Pontoscolex corethrurus, on nematode community structure in a 5-month field mesocosm experiment conducted in Madagascar. Ten different treatments with or without earthworms and with or without organic residues (rice, soybean were compared. Organic residues were applied on the soil surface or mixed with the soil. The abundance of nematodes (bacterial and fungal feeders was higher in presence of P. corethrurus than in their absence. The type of plant residues as well as their localisation had significant effects on the abundance and composition of soil nematodes. The analysis of nematode community structure showed that earthworm activity led to an overall activation of the microbial compartment without specific stimulation of the bacterial or fungal compartment.

Management of the potato cyst nematode (Globodera pallida) with bio-fumigants/stimulants.

Science.gov (United States)

Martin, T J G; Turner, S J; Fleming, C C

2007-01-01

Field trials evaluated the effect of four plant-based bio-fumigants/stimulants on population levels of G. pallida and the resulting potato yields and quality. Three formulations contained seaweed biostimulants (Algifol, Nutridip and Metastim) and one bio-fumigant containing mustard and chilli pepper extracts (Dazitol). These were compared with the fumigant nematicide Nemathorin and untreated control plots. The effect of G. pallida on growing potato crops was assessed by recording haulm characteristics which indicated that the nematicide treatment gave most protection. Levels of PCN juveniles and migratory nematodes were assessed during the trial. Plots treated with Nemathorin and Dazitol had fewest PCN, whilst the highest number of migratory nematodes occurred in fallow plots. Sixteen weeks after planting the nematicide treatment produced highest yield and tuber numbers. Dazitol treatment produced a lower yield but the largest tubers.

On the track of transfer cell formation by specialized plant-parasitic nematodes.

Science.gov (United States)

Rodiuc, Natalia; Vieira, Paulo; Banora, Mohamed Youssef; de Almeida Engler, Janice

2014-01-01

Transfer cells are ubiquitous plant cells that play an important role in plant development as well as in responses to biotic and abiotic stresses. They are highly specialized and differentiated cells playing a central role in the acquisition, distribution and exchange of nutrients. Their unique structural traits are characterized by augmented ingrowths of invaginated secondary wall material, unsheathed by an amplified area of plasma membrane enriched in a suite of solute transporters. Similar morphological features can be perceived in vascular root feeding cells induced by sedentary plant-parasitic nematodes, such as root-knot and cyst nematodes, in a wide range of plant hosts. Despite their close phylogenetic relationship, these obligatory biotrophic plant pathogens engage different approaches when reprogramming root cells into giant cells or syncytia, respectively. Both nematode feeding-cells types will serve as the main source of nutrients until the end of the nematode life cycle. In both cases, these nematodes are able to remarkably maneuver and reprogram plant host cells. In this review we will discuss the structure, function and formation of these specialized multinucleate cells that act as nutrient transfer cells accumulating and synthesizing components needed for survival and successful offspring of plant-parasitic nematodes. Plant cells with transfer-like functions are also a renowned subject of interest involving still poorly understood molecular and cellular transport processes.

On the track of transfer cells formation by specialized plant-parasitic nematodes

Directory of Open Access Journals (Sweden)

Natalia eRodiuc

2014-05-01

Full Text Available Transfer cells are ubiquitous plant cells that play an important role in plant development as well as in responses to biotic and abiotic stresses. They are highly specialized and differentiated cells playing a central role in the acquisition, distribution and exchange of nutrients. Their unique structural traits are characterized by augmented ingrowths of invaginated secondary wall material, unsheathed by an amplified area of plasma membrane enriched in a suite of solute transporters. Similar morphological features can be perceived in vascular root feeding cells induced by sedentary plant-parasitic nematodes, such as root-knot and cyst nematodes, in a wide range of plant hosts. Despite their close phylogenetic relationship, these obligatory biotrophic plant pathogens engage different approaches when reprogramming root cells into giant cells or syncytia, respectively. Both nematode feeding-cells types will serve as the main source of nutrients until the end of the nematode life cycle. In both cases, these nematodes are able to remarkably maneuver and reprogram plant host cells. In this review we will discuss the structural, functional and morphogenetic characteristics function and formation of these specialized multinucleate cells that act as nutrient transfer cells to accumulate and synthesize components needed for survival and successful offspring of plant-parasitic nematodes. Plant cells with transfer-like functions are also a renowned subject of interest involving still poorly understood molecular and cellular transport processes.

flp-32 Ligand/receptor silencing phenocopy faster plant pathogenic nematodes.

Science.gov (United States)

Atkinson, Louise E; Stevenson, Michael; McCoy, Ciaran J; Marks, Nikki J; Fleming, Colin; Zamanian, Mostafa; Day, Tim A; Kimber, Michael J; Maule, Aaron G; Mousley, Angela

2013-02-01

Restrictions on nematicide usage underscore the need for novel control strategies for plant pathogenic nematodes such as Globodera pallida (potato cyst nematode) that impose a significant economic burden on plant cultivation activities. The nematode neuropeptide signalling system is an attractive resource for novel control targets as it plays a critical role in sensory and motor functions. The FMRFamide-like peptides (FLPs) form the largest and most diverse family of neuropeptides in invertebrates, and are structurally conserved across nematode species, highlighting the utility of the FLPergic system as a broad-spectrum control target. flp-32 is expressed widely across nematode species. This study investigates the role of flp-32 in G. pallida and shows that: (i) Gp-flp-32 encodes the peptide AMRNALVRFamide; (ii) Gp-flp-32 is expressed in the brain and ventral nerve cord of G. pallida; (iii) migration rate increases in Gp-flp-32-silenced worms; (iv) the ability of G. pallida to infect potato plant root systems is enhanced in Gp-flp-32-silenced worms; (v) a novel putative Gp-flp-32 receptor (Gp-flp-32R) is expressed in G. pallida; and, (vi) Gp-flp-32R-silenced worms also display an increase in migration rate. This work demonstrates that Gp-flp-32 plays an intrinsic role in the modulation of locomotory behaviour in G. pallida and putatively interacts with at least one novel G-protein coupled receptor (Gp-flp-32R). This is the first functional characterisation of a parasitic nematode FLP-GPCR.

flp-32 Ligand/receptor silencing phenocopy faster plant pathogenic nematodes.

Directory of Open Access Journals (Sweden)

Louise E Atkinson

2013-02-01

Full Text Available Restrictions on nematicide usage underscore the need for novel control strategies for plant pathogenic nematodes such as Globodera pallida (potato cyst nematode that impose a significant economic burden on plant cultivation activities. The nematode neuropeptide signalling system is an attractive resource for novel control targets as it plays a critical role in sensory and motor functions. The FMRFamide-like peptides (FLPs form the largest and most diverse family of neuropeptides in invertebrates, and are structurally conserved across nematode species, highlighting the utility of the FLPergic system as a broad-spectrum control target. flp-32 is expressed widely across nematode species. This study investigates the role of flp-32 in G. pallida and shows that: (i Gp-flp-32 encodes the peptide AMRNALVRFamide; (ii Gp-flp-32 is expressed in the brain and ventral nerve cord of G. pallida; (iii migration rate increases in Gp-flp-32-silenced worms; (iv the ability of G. pallida to infect potato plant root systems is enhanced in Gp-flp-32-silenced worms; (v a novel putative Gp-flp-32 receptor (Gp-flp-32R is expressed in G. pallida; and, (vi Gp-flp-32R-silenced worms also display an increase in migration rate. This work demonstrates that Gp-flp-32 plays an intrinsic role in the modulation of locomotory behaviour in G. pallida and putatively interacts with at least one novel G-protein coupled receptor (Gp-flp-32R. This is the first functional characterisation of a parasitic nematode FLP-GPCR.

Evidence of animal mtDNA recombination between divergent populations of the potato cyst nematode Globodera pallida.

Science.gov (United States)

Hoolahan, Angelique H; Blok, Vivian C; Gibson, Tracey; Dowton, Mark

2012-03-01

Recombination is typically assumed to be absent in animal mitochondrial genomes (mtDNA). However, the maternal mode of inheritance means that recombinant products are indistinguishable from their progenitor molecules. The majority of studies of mtDNA recombination assess past recombination events, where patterns of recombination are inferred by comparing the mtDNA of different individuals. Few studies assess contemporary mtDNA recombination, where recombinant molecules are observed as direct mosaics of known progenitor molecules. Here we use the potato cyst nematode, Globodera pallida, to investigate past and contemporary recombination. Past recombination was assessed within and between populations of G. pallida, and contemporary recombination was assessed in the progeny of experimental crosses of these populations. Breeding of genetically divergent organisms may cause paternal mtDNA leakage, resulting in heteroplasmy and facilitating the detection of recombination. To assess contemporary recombination we looked for evidence of recombination between the mtDNA of the parental populations within the mtDNA of progeny. Past recombination was detected between a South American population and several UK populations of G. pallida, as well as between two South American populations. This suggests that these populations may have interbred, paternal mtDNA leakage occurred, and the mtDNA of these populations subsequently recombined. This evidence challenges two dogmas of animal mtDNA evolution; no recombination and maternal inheritance. No contemporary recombination between the parental populations was detected in the progeny of the experimental crosses. This supports current arguments that mtDNA recombination events are rare. More sensitive detection methods may be required to adequately assess contemporary mtDNA recombination in animals.

Enhancement of the efficacy of a carbamate nematicide against the potato cyst nematode, Globodera pallida, through mycorrhization in commercial potato fields.

Science.gov (United States)

Deliopoulos, T; Minnis, S T; Jones, P W; Haydock, P P J

2010-03-01

Two experiments were conducted over 2 years in commercial potato fields in Shropshire, UK, to evaluate the compatibility of the nematicide aldicarb with commercial inocula of arbuscular mycorrhizal fungi (AMF) in the control of the potato cyst nematode Globodera pallida. The AMF used were Vaminoc (mixed-AMF inoculum), Glomus intraradices (BioRize BB-E) and G. mosseae (isolate BEG 12). In the absence of AMF, the in-soil hatch of G. pallida increased 30% (P potato (cv. Golden Wonder) tubers with AMF eliminated this delay in G. pallida hatch by stimulating a mean increase of 32% (P < 0.01) in hatch within 2 wk after planting. In the aldicarb-treated plots in Experiment 1, G. pallida multiplication rate was 38% lower (P < 0.05) in roots of AMF-inoculated than noninoculated plants, but in Experiment 2, this effect was slightly lower (P = 0.07). In these plots, the single AMF inocula showed also a weak trend (P = 0.10) towards greater tuber yields relative to their noninoculated counterparts. Mycorrhization therefore appears to enhance the efficacy of carbamate nematicides against G. pallida and consequently more research is proposed to validate these findings and fully explore the potential of this model.

The Effect of Temperature, Potato Varieties, and The Origin Of Cyst on The Reproductive Biology of Globodera rostochiensis

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Nurjanah Nurjanah

2016-12-01

Full Text Available Potato cyst nematode (Globodera rostochiensis [Wollenweber] Behrens is a nematode species of worldwide regulatory concern. This nematode caused serious economic of potato losses in Indonesia. This research studied by factorial designed to evaluated the effect of temperature (10, 20, and 30ºC, potato varieties (`Granola´, `Margahayu´, and `Cipanas´, and origin of cyst (West, Central, and East Java on reproductive biology of G. rostochiensis in the growth chamber. The research was conducted by observed of produced the new cyst number, reproduction fitness, survival, fecundity, and multiplication of G. rostochiensis. The result showed that all of the potato varieties were infected by G. rostochiensis when they were grown at the temperature ranging of 20 and 30ºC but not at 10ºC. The optimum temperature for maximum number of cysts with the highest reproduction factor, survival, fecundity and multiplication rate for all populations was 20ºC. The origin of cyst did not have any effect on the reproductive rate. The temperature of 20ºC provided is best environment for the life of G. rostochiensis on Granola.   INTISARI Nematoda sista kentang (Globodera rostochiensis [Wollenweber] Behrens adalah spesies nematoda yang mendapatkan perhatian khusus di seluruh dunia. G. rostochiensis menyebabkan kerugian ekonomi yang serius pada pertanaman kentang di Indonesia. Penelitian ini menguji pengaruh perbedaan suhu (10, 20, dan 30ºC, varietas kentang (Granola, Cipanas, dan Margahayu, dan asal sista (Jawa Barat, Jawa Tengah, dan Jawa Timur terhadap biologi reproduksi G. rostochiensis di growth chamber menggunakan rancangan acak lengkap faktorial. Pengamatan dilakukan terhadap jumlah sista baru, kemampuan reproduksi, daya tahan hidup, keperidian dan multiplikasi G. rostochiensis. Seluruh varietas kentang yang diuji terserang G. rostochiensis pada suhu 20 dan 30ºC kecuali pada suhu 10ºC. Kisaran suhu optimum untuk memperoleh jumlah sista baru yang maksimum

The genome and life-stage specific transcriptomes of Globodera pallida elucidate key aspects of plant parasitism by a cyst nematode

KAUST Repository

Cotton, James A; Lilley, Catherine J; Jones, Laura M; Kikuchi, Taisei; Reid, Adam J; Thorpe, Peter; Tsai, Isheng J; Beasley, Helen; Blok, Vivian; Cock, Peter J A; den Akker, Sebastian Eves-van; Holroyd, Nancy; Hunt, Martin; Mantelin, Sophie; Naghra, Hardeep; Pain, Arnab; Palomares-Rius, Juan E; Zarowiecki, Magdalena; Berriman, Matthew; Jones, John T; Urwin, Peter E

2014-01-01

-knot nematodes are the two most important plant parasitic nematode groups and together represent a global threat to food security. Results: We present the complete genome sequence of G. pallida, together with transcriptomic data from most of the nematode life

Validation of microsatellite markers for assisted selection of soybean resistance to cyst nematode races 3 and 14 Validação de marcadores microssatélites para a seleção assistida de resistência de soja ao nematóide-de-cisto raças 3 e 14

Directory of Open Access Journals (Sweden)

Marcia Flores da Silva

2007-08-01

Full Text Available The objective of this work was to validate microsatellite markers associated with resistance to soybean cyst nematode (Heterodera glycines Ichinohe races 3 and 14, in soybean (Glycine max L. genotypes, for use in marker-assisted selection (MAS programs. Microsatellites of soybean linkage groups A2, D2 and G were tested in two populations, and their selection efficiencies were determined. The populations were 65 F2:3 families from Msoy8001 (resistant x Conquista (susceptible cross, and 66 F2:3 families of S5995 (resistant x Renascença (susceptible cross, evaluated for resistance to races 3 and 14, respectively. Families with female index up to 30% were considered moderately resistant. Markers of A2 and G linkage groups were associated with resistance to race 3. Markers Satt309 and GMENOD2B explained the greatest proportion of phenotypic variance in the different groups. The combinations Satt309+GMENOD2B and Satt309+Satt187 presented 100% selection efficiency. Resistance to race 14 was associated with markers of G linkage group, and selection efficiency in the Satt309+Satt356 combination was 100%. The selection differential obtained by phenotypic and marker assisted selection showed that both can result in similar gains.O objetivo deste trabalho foi validar marcadores microssatélites associados à resistência às raças 3 e 14 do nematóide-de-cisto (Heterodera glycines Ichinohe da soja (Glycine max L., para serem utilizados em programas de seleção assistida por marcadores moleculares (SAM. Microssatélites dos grupos de ligação A2, D2 e G da soja foram testados em duas populações, e suas eficiências de seleção foram determinadas. As populações foram 65 famílias F2:3, do cruzamento Msoy8001 (resistente x Conquista (suscetível, e 66 famílias F2:3, do cruzamento S5995 (resistente x Renascença (suscetível, avaliadas para a resistência às raças 3 e 14, respectivamente. Famílias com índice de fêmeas de até 30% foram

A metagenetic approach to determine the diversity and distribution of cyst nematodes at the level of the country, the field and the individual.

Science.gov (United States)

Eves-van den Akker, Sebastian; Lilley, Catherine J; Reid, Alex; Pickup, Jon; Anderson, Eric; Cock, Peter J A; Blaxter, Mark; Urwin, Peter E; Jones, John T; Blok, Vivian C

2015-12-01

Distinct populations of the potato cyst nematode (PCN) Globodera pallida exist in the UK that differ in their ability to overcome various sources of resistance. An efficient method for distinguishing between populations would enable pathogen-informed cultivar choice in the field. Science and Advice for Scottish Agriculture (SASA) annually undertake national DNA diagnostic tests to determine the presence of PCN in potato seed and ware land by extracting DNA from soil floats. These DNA samples provide a unique resource for monitoring the distribution of PCN and further interrogation of the diversity within species. We identify a region of mitochondrial DNA descriptive of three main groups of G. pallida present in the UK and adopt a metagenetic approach to the sequencing and analysis of all SASA samples simultaneously. Using this approach, we describe the distribution of G. pallida mitotypes across Scotland with field-scale resolution. Most fields contain a single mitotype, one-fifth contain a mix of mitotypes, and less than 3% contain all three mitotypes. Within mixed fields, we were able to quantify the relative abundance of each mitotype across an order of magnitude. Local areas within mixed fields are dominated by certain mitotypes and indicate towards a complex underlying 'pathoscape'. Finally, we assess mitotype distribution at the level of the individual cyst and provide evidence of 'hybrids'. This study provides a method for accurate, quantitative and high-throughput typing of up to one thousand fields simultaneously, while revealing novel insights into the national genetic variability of an economically important plant parasite. © 2015 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

A ubiquitin carboxyl extension protein secreted from a plant-parasitic nematode Globodera rostochiensis is cleaved in planta to promote plant parasitism.

Science.gov (United States)

Chronis, Demosthenis; Chen, Shiyan; Lu, Shunwen; Hewezi, Tarek; Carpenter, Sara C D; Loria, Rosemary; Baum, Thomas J; Wang, Xiaohong

2013-04-01

Nematode effector proteins originating from esophageal gland cells play central roles in suppressing plant defenses and in formation of the plant feeding cells that are required for growth and development of cyst nematodes. A gene (GrUBCEP12) encoding a unique ubiquitin carboxyl extension protein (UBCEP) that consists of a signal peptide for secretion, a mono-ubiquitin domain, and a 12 amino acid carboxyl extension protein (CEP12) domain was cloned from the potato cyst nematode Globodera rostochiensis. This GrUBCEP12 gene was expressed exclusively within the nematode's dorsal esophageal gland cell, and was up-regulated in the parasitic second-stage juvenile, correlating with the time when feeding cell formation is initiated. We showed that specific GrUBCEP12 knockdown via RNA interference reduced nematode parasitic success, and that over-expression of the secreted Gr(Δ) (SP) UBCEP12 protein in potato resulted in increased nematode susceptibility, providing direct evidence that this secreted effector is involved in plant parasitism. Using transient expression assays in Nicotiana benthamiana, we found that Gr(Δ) (SP) UBCEP12 is processed into free ubiquitin and a CEP12 peptide (GrCEP12) in planta, and that GrCEP12 suppresses resistance gene-mediated cell death. A target search showed that expression of RPN2a, a gene encoding a subunit of the 26S proteasome, was dramatically suppressed in Gr(Δ) (SP) UBCEP12 but not GrCEP12 over-expression plants when compared with control plants. Together, these results suggest that, when delivered into host plant cells, Gr(Δ) (SP) UBCEP12 becomes two functional units, one acting to suppress plant immunity and the other potentially affecting the host 26S proteasome, to promote feeding cell formation. © 2013 The Authors The Plant Journal © 2013 Blackwell Publishing Ltd.

Nematodes

International Nuclear Information System (INIS)

Suzuki, Kenshi; Ishii, Naoaki

1977-01-01

Utilization of nematodes for a study of radiation biology was considered. Structure, generation, rearing method, and genetic nature of nematodes (Caenorhabditis elegans, Turbatri acetic, etc.) were given an outline. As the advantage of a study using nematodes as materials, shortness of one generation time, simplicity in structure, and smallness of the whole cells, specific regular movement, and heliotaxis to chemical substances and light were mentioned. Effect of x-ray on survival rate of nematodes and effect of ultraviolet on nematodes and their eggs were described. It was suggested that nematodes was useful for studies on aging and radiation biology, and a possibility existed that nematodes would be used in studies of cancer and malformation. (Serizawa, K.)

Genetic and physical mapping of homologues of the virus resistance gene Rx1 and the cyst nematode resistance gene Gpa2 in potato.

Science.gov (United States)

Bakker, E; Butterbach, P; Rouppe van der Voort, J; van der Vossen, E; van Vliet, J; Bakker, J; Goverse, A

2003-05-01

Nine resistance gene homologues (RGHs) were identified in two diploid potato clones (SH and RH), with a specific primer pair based on conserved motifs in the LRR domain of the potato cyst nematode resistance gene Gpa2 and the potato virus X resistance gene Rx1. A modified AFLP method was used to facilitate the genetic mapping of the RGHs in the four haplotypes under investigation. All nine RGHs appeared to be located in the Gpa2/ Rx1 cluster on chromosome XII. Construction of a physical map using bacterial artificial chromosome (BAC) clones for both the Solanum tuberosum ssp. tuberosum and the S. tuberosum ssp. andigena haplotype of SH showed that the RGHs are located within a stretch of less than 200 kb. Sequence analysis of the RGHs revealed that they are highly similar (93 to 95%) to Gpa2 and Rx1. The sequence identities among all RGHs range from 85 to 100%. Two pairs of RGHs are identical, or nearly so (100 and 99.9%), with each member located in a different genotype. Southern-blot analysis on genomic DNA revealed no evidence for additional homologues outside the Gpa2/ Rx1 cluster on chromosome XII.

A high-resolution map of the H1 locus harbouring resistance to the potato cyst nematode Globodera rostochiensis.

Science.gov (United States)

Bakker, Erin; Achenbach, Ute; Bakker, Jeroen; van Vliet, Joke; Peleman, Johan; Segers, Bart; van der Heijden, Stefan; van der Linde, Piet; Graveland, Robert; Hutten, Ronald; van Eck, Herman; Coppoolse, Eric; van der Vossen, Edwin; Bakker, Jaap; Goverse, Aska

2004-06-01

The resistance gene H1 confers resistance to the potato cyst nematode Globodera rostochiensis and is located at the distal end of the long arm of chromosome V of potato. For marker enrichment of the H1 locus, a bulked segregant analysis (BSA) was carried out using 704 AFLP primer combinations. A second source of markers tightly linked to H1 is the ultra-high-density (UHD) genetic map of the potato cross SH x RH. This map has been produced with 387 AFLP primer combinations and consists of 10,365 AFLP markers in 1,118 bins (http://www.dpw.wageningen-ur.nl/uhd/). Comparing these two methods revealed that BSA resulted in one marker/cM and the UHD map in four markers/cM in the H1 interval. Subsequently, a high-resolution genetic map of the H1 locus has been developed using a segregating F(1) SH x RH population consisting of 1,209 genotypes. Two PCR-based markers were designed at either side of the H1 gene to screen the 1,209 genotypes for recombination events. In the high-resolution genetic map, two of the four co-segregating AFLP markers could be separated from the H1 gene. Marker EM1 is located at a distance of 0.2 cM, and marker EM14 is located at a distance of 0.8 cM. The other two co-segregating markers CM1 (in coupling) and EM15 (in repulsion) could not be separated from the H1 gene.

Phloem development in nematode-induced feeding sites: The implications of auxin and cytokinin

Directory of Open Access Journals (Sweden)

Birgit eAbsmanner

2013-07-01

Full Text Available Sedentary plant parasitic nematodes such as root-knot nematodes and cyst nematodes induce giant cells or syncytia, respectively, in their host plant’s roots. These highly specialized structures serve as feeding sites from which exclusively the nematodes withdraw nutrients. While giant cells are symplastically isolated and obtain assimilates by transporter-mediated processes syncytia are massively connected to the phloem by plasmodesmata. To support the feeding sites and the nematode during their development, phloem is induced around syncytia and giant cells. In the case of syncytia the unloading phloem consists of sieve elements and companion cells and in the case of root knots it consists exclusively of sieve elements. We applied immunohistochemistry to identify the cells within the developing phloem that responded to auxin and cytokinin. Both feeding sites themselves did not respond to either hormone. We were able to show that in root knots an auxin response precedes the differentiation of these auxin responsive cells into phloem elements. This process appears to be independent of B-type Arabidopsis response regulators. Using additional markers for tissue identity we provide evidence that around giant cells protophloem is formed and proliferates dramatically. In contrast, the phloem around syncytia responded to both hormones. The presence of companion cells as well as hormone-responsive sieve elements suggests that metaphloem development occurs. The implication of auxin and cytokinin in the further development of the metaphloem is discussed.

Orthokeratinised odontogenic cyst mimicking periapical cyst

OpenAIRE

Rajalakshmi, R; Sreeja, C; Vijayalakshmi, D; Leelarani, V

2013-01-01

Orthokeratinised odontogenic cyst (OOC) denotes the odontogenic cyst that microscopically has an orthokeratinised epithelial lining. OOC is characterised by a less-aggressive behaviour and a low rate of recurrence. This report describes a case of OOC involving posterior part of the mandible that mimicked periapical cyst in a 14-year-old boy. The initial clinical diagnosis was given as periapical cyst based on the clinical and radiographical features. Enucleation of the cyst was performed and ...

Cell wall ingrowths in nematode induced syncytia require UGD2 and UGD3.

Directory of Open Access Journals (Sweden)

Shahid Siddique

Full Text Available The cyst nematode Heterodera schachtii infects roots of Arabidopsis plants and establishes feeding sites called syncytia, which are the only nutrient source for nematodes. Development of syncytia is accompanied by changes in cell wall structures including the development of cell wall ingrowths. UDP-glucuronic acid is a precursor of several cell wall polysaccharides and can be produced by UDP-glucose dehydrogenase through oxidation of UDP-glucose. Four genes in Arabidopsis encode this enzyme. Promoter::GUS analysis revealed that UGD2 and UGD3 were expressed in syncytia as early as 1 dpi while expression of UGD1 and UGD4 could only be detected starting at 2 dpi. Infection assays showed no differences between Δugd1 and Δugd4 single mutants and wild type plants concerning numbers of males and females and the size of syncytia and cysts. On single mutants of Δugd2 and Δugd3, however, less and smaller females, and smaller syncytia formed compared to wild type plants. The double mutant ΔΔugd23 had a stronger effect than the single mutants. These data indicate that UGD2 and UGD3 but not UGD1 and UGD4 are important for syncytium development. We therefore studied the ultrastructure of syncytia in the ΔΔugd23 double mutant. Syncytia contained an electron translucent cytoplasm with degenerated cellular organelles and numerous small vacuoles instead of the dense cytoplasm as in syncytia developing in wild type roots. Typical cell wall ingrowths were missing in the ΔΔugd23 double mutant. Therefore we conclude that UGD2 and UGD3 are needed for the production of cell wall ingrowths in syncytia and that their lack leads to a reduced host suitability for H. schachtii resulting in smaller syncytia, lower number of developing nematodes, and smaller females.

Online Analytical Processing (OLAP: A Fast and Effective Data Mining Tool for Gene Expression Databases

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Alkharouf Nadim W.

2005-01-01

Full Text Available Gene expression databases contain a wealth of information, but current data mining tools are limited in their speed and effectiveness in extracting meaningful biological knowledge from them. Online analytical processing (OLAP can be used as a supplement to cluster analysis for fast and effective data mining of gene expression databases. We used Analysis Services 2000, a product that ships with SQLServer2000, to construct an OLAP cube that was used to mine a time series experiment designed to identify genes associated with resistance of soybean to the soybean cyst nematode, a devastating pest of soybean. The data for these experiments is stored in the soybean genomics and microarray database (SGMD. A number of candidate resistance genes and pathways were found. Compared to traditional cluster analysis of gene expression data, OLAP was more effective and faster in finding biologically meaningful information. OLAP is available from a number of vendors and can work with any relational database management system through OLE DB.

Comparative genome analysis and resistance gene mapping in grain legumes

International Nuclear Information System (INIS)

Young, N.D.

1998-01-01

Using, DNA markers and genome organization, several important disease resistance genes have been analyzed in mungbean (Vigna radiata), cowpea (Vigna unguiculata), common bean (Phaseolus vulgaris), and soybean (Glycine max). In the process, medium-density linkage maps consisting of restriction fragment length polymorphism (RFLP) markers were constructed for both mungbean and cowpea. Comparisons between these maps, as well as the maps of soybean and common bean, indicate that there is significant conservation of DNA marker order, though the conserved blocks in soybean are much shorter than in the others. DNA mapping results also indicate that a gene for seed weight may be conserved between mungbean and cowpea. Using the linkage maps, genes that control bruchid (genus Callosobruchus) and powdery mildew (Erysiphe polygoni) resistance in mungbean, aphid resistance in cowpea (Aphis craccivora), and cyst nematode (Heterodera glycines) resistance in soybean have all been mapped and characterized. For some of these traits resistance was found to be oligogenic and DNA mapping uncovered multiple genes involved in the phenotype. (author)

Online analytical processing (OLAP): a fast and effective data mining tool for gene expression databases.

Science.gov (United States)

Alkharouf, Nadim W; Jamison, D Curtis; Matthews, Benjamin F

2005-06-30

Gene expression databases contain a wealth of information, but current data mining tools are limited in their speed and effectiveness in extracting meaningful biological knowledge from them. Online analytical processing (OLAP) can be used as a supplement to cluster analysis for fast and effective data mining of gene expression databases. We used Analysis Services 2000, a product that ships with SQLServer2000, to construct an OLAP cube that was used to mine a time series experiment designed to identify genes associated with resistance of soybean to the soybean cyst nematode, a devastating pest of soybean. The data for these experiments is stored in the soybean genomics and microarray database (SGMD). A number of candidate resistance genes and pathways were found. Compared to traditional cluster analysis of gene expression data, OLAP was more effective and faster in finding biologically meaningful information. OLAP is available from a number of vendors and can work with any relational database management system through OLE DB.

A multipartite mitochondrial genome in the potato cyst nematode Globodera pallida.

Science.gov (United States)

Armstrong, M R; Blok, V C; Phillips, M S

2000-01-01

The mitochondrial genome (mtDNA) of the plant parasitic nematode Globodera pallida exists as a population of small, circular DNAs that, taken individually, are of insufficient length to encode the typical metazoan mitochondrial gene complement. As far as we are aware, this unusual structural organization is unique among higher metazoans, although interesting comparisons can be made with the multipartite mitochondrial genome organizations of plants and fungi. The variation in frequency between populations displayed by some components of the mtDNA is likely to have major implications for the way in which mtDNA can be used in population and evolutionary genetic studies of G. pallida.

Apoplastic Venom Allergen-like Proteins of Cyst Nematodes Modulate the Activation of Basal Plant Innate Immunity by Cell Surface Receptors

NARCIS (Netherlands)

Lozano Torres, J.L.; Wilbers, R.H.P.; Warmerdam, S.; Finkers-Tomczak, A.M.; Diaz Granados Muñoz, A.; Schaik, van C.C.; Helder, J.; Bakker, J.; Goverse, A.; Schots, A.; Smant, G.

2014-01-01

Despite causing considerable damage to host tissue during the onset of parasitism, nematodes establish remarkably persistent infections in both animals and plants. It is thought that an elaborate repertoire of effector proteins in nematode secretions suppresses damage-triggered immune responses of

Analysis of putative apoplastic effectors from the nematode, Globodera rostochiensis, and identification of an expansin-like protein that can induce and suppress host defenses.

Science.gov (United States)

Ali, Shawkat; Magne, Maxime; Chen, Shiyan; Côté, Olivier; Stare, Barbara Gerič; Obradovic, Natasa; Jamshaid, Lubna; Wang, Xiaohong; Bélair, Guy; Moffett, Peter

2015-01-01

The potato cyst nematode, Globodera rostochiensis, is an important pest of potato. Like other pathogens, plant parasitic nematodes are presumed to employ effector proteins, secreted into the apoplast as well as the host cytoplasm, to alter plant cellular functions and successfully infect their hosts. We have generated a library of ORFs encoding putative G. rostochiensis putative apoplastic effectors in vectors for expression in planta. These clones were assessed for morphological and developmental effects on plants as well as their ability to induce or suppress plant defenses. Several CLAVATA3/ESR-like proteins induced developmental phenotypes, whereas predicted cell wall-modifying proteins induced necrosis and chlorosis, consistent with roles in cell fate alteration and tissue invasion, respectively. When directed to the apoplast with a signal peptide, two effectors, an ubiquitin extension protein (GrUBCEP12) and an expansin-like protein (GrEXPB2), suppressed defense responses including NB-LRR signaling induced in the cytoplasm. GrEXPB2 also elicited defense response in species- and sequence-specific manner. Our results are consistent with the scenario whereby potato cyst nematodes secrete effectors that modulate host cell fate and metabolism as well as modifying host cell walls. Furthermore, we show a novel role for an apoplastic expansin-like protein in suppressing intra-cellular defense responses.

Analysis of putative apoplastic effectors from the nematode, Globodera rostochiensis, and identification of an expansin-like protein that can induce and suppress host defenses.

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Shawkat Ali

Full Text Available The potato cyst nematode, Globodera rostochiensis, is an important pest of potato. Like other pathogens, plant parasitic nematodes are presumed to employ effector proteins, secreted into the apoplast as well as the host cytoplasm, to alter plant cellular functions and successfully infect their hosts. We have generated a library of ORFs encoding putative G. rostochiensis putative apoplastic effectors in vectors for expression in planta. These clones were assessed for morphological and developmental effects on plants as well as their ability to induce or suppress plant defenses. Several CLAVATA3/ESR-like proteins induced developmental phenotypes, whereas predicted cell wall-modifying proteins induced necrosis and chlorosis, consistent with roles in cell fate alteration and tissue invasion, respectively. When directed to the apoplast with a signal peptide, two effectors, an ubiquitin extension protein (GrUBCEP12 and an expansin-like protein (GrEXPB2, suppressed defense responses including NB-LRR signaling induced in the cytoplasm. GrEXPB2 also elicited defense response in species- and sequence-specific manner. Our results are consistent with the scenario whereby potato cyst nematodes secrete effectors that modulate host cell fate and metabolism as well as modifying host cell walls. Furthermore, we show a novel role for an apoplastic expansin-like protein in suppressing intra-cellular defense responses.

Characterization of susceptibility and resistance responses to potato cyst nematode (Globodera spp.) infection of tomato lines in the absence and presence of the broad-spectrum nematode resistance Hero gene.

Science.gov (United States)

Sobczak, Miroslaw; Avrova, Anna; Jupowicz, Justyna; Phillips, Mark S; Ernst, Karin; Kumar, Amar

2005-02-01

The tomato Hero A gene is the only member of a multigene family that confers a high level (>80%) of resistance to all the economically important pathotypes of potato cyst nematode (PCN) species Globodera rostochiensis and G. pallida. Although the resistance levels of transgenic tomato lines were similar to those of the tomato line LA1792 containing the introgressed Hero multigene family, transgenic potato plants expressing the tomato Hero A gene are not resistant to PCNs. Comparative microscopy studies of in vitro infected roots of PCN-susceptible tomato cv. Money Maker, the resistant breeding line LA1792, and transgenic line L10 with Ro1 pathotype have revealed no statistically significant difference in the number of juveniles invading roots. However, syncytia (specialized feeding cells) induced in LA1792 and L10 roots mostly were found to have degenerated a few days after their induction, and a few surviving syncytia were able to support only the development of males rather than females. Thus, the ratio between males and females was biased towards males on LA1792 and L10 roots. A series of changes occur in resistant plants leading to formation of a layer of necrotic cells separating the syncytium from stellar conductive tissues and this is followed by degradation of the syncytium. Although the Hero A gene is expressed in all tissues, including roots, stems, leaves, and flower buds, its expression is upregulated in roots in response to PCN infection. Moreover, the expression profiles of the Hero A correlates with the timing of death of the syncytium.

In Planta Processing and Glycosylation of a Nematode CLAVATA3/ENDOSPERM SURROUNDING REGION-Like Effector and Its Interaction with a Host CLAVATA2-Like Receptor to Promote Parasitism1[OPEN

Science.gov (United States)

Chen, Shiyan; Lang, Ping; Chronis, Demosthenis; Zhang, Sheng; De Jong, Walter S.; Mitchum, Melissa G.

2015-01-01

Like other biotrophic plant pathogens, plant-parasitic nematodes secrete effector proteins into host cells to facilitate infection. Effector proteins that mimic plant CLAVATA3/ENDOSPERM SURROUNDING REGION-related (CLE) proteins have been identified in several cyst nematodes, including the potato cyst nematode (PCN); however, the mechanistic details of this cross-kingdom mimicry are poorly understood. Plant CLEs are posttranslationally modified and proteolytically processed to function as bioactive ligands critical to various aspects of plant development. Using ectopic expression coupled with nanoliquid chromatography-tandem mass spectrometry analysis, we show that the in planta mature form of proGrCLE1, a multidomain CLE effector secreted by PCN during infection, is a 12-amino acid arabinosylated glycopeptide (named GrCLE1-1Hyp4,7g) with striking structural similarity to mature plant CLE peptides. This glycopeptide is more resistant to hydrolytic degradation and binds with higher affinity to a CLAVATA2-like receptor (StCLV2) from potato (Solanum tuberosum) than its nonglycosylated forms. We further show that StCLV2 is highly up-regulated at nematode infection sites and that transgenic potatoes with reduced StCLV2 expression are less susceptible to PCN infection, indicating that interference of the CLV2-mediated signaling pathway confers nematode resistance in crop plants. These results strongly suggest that phytonematodes have evolved to utilize host cellular posttranslational modification and processing machinery for the activation of CLE effectors following secretion into plant cells and highlight the significance of arabinosylation in regulating nematode CLE effector activity. Our finding also provides evidence that multidomain CLEs are modified and processed similarly to single-domain CLEs, adding new insight into CLE maturation in plants. PMID:25416475

Inflammatory dentigerous cyst mimicking a periapical cyst

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Priya Gupta

2016-01-01

Full Text Available Odontogenic cysts are the most common form of cystic lesions that affect the maxillofacial region. The low frequency of dentigerous cysts in children has been reported in dental literature. Dentigerous cysts arise as a result of cystic change in the remains of the enamel organ after the process of enamel formation is complete. They enclose the crown of an unerupted tooth and are attached to the cementoenamel junction. Although most dentigerous cysts are considered developmental cysts, some cases seem to have an inflammatory origin. The purpose of this report is to present a case of an 8-year-old male patient with a dentigerous cyst of inflammatory origin.

Discrimination of plant-parasitic nematodes from complex soil communities using ecometagenetics.

Science.gov (United States)

Porazinska, Dorota L; Morgan, Matthew J; Gaspar, John M; Court, Leon N; Hardy, Christopher M; Hodda, Mike

2014-07-01

Many plant pathogens are microscopic, cryptic, and difficult to diagnose. The new approach of ecometagenetics, involving ultrasequencing, bioinformatics, and biostatistics, has the potential to improve diagnoses of plant pathogens such as nematodes from the complex mixtures found in many agricultural and biosecurity situations. We tested this approach on a gradient of complexity ranging from a few individuals from a few species of known nematode pathogens in a relatively defined substrate to a complex and poorly known suite of nematode pathogens in a complex forest soil, including its associated biota of unknown protists, fungi, and other microscopic eukaryotes. We added three known but contrasting species (Pratylenchus neglectus, the closely related P. thornei, and Heterodera avenae) to half the set of substrates, leaving the other half without them. We then tested whether all nematode pathogens-known and unknown, indigenous, and experimentally added-were detected consistently present or absent. We always detected the Pratylenchus spp. correctly and with the number of sequence reads proportional to the numbers added. However, a single cyst of H. avenae was only identified approximately half the time it was present. Other plant-parasitic nematodes and nematodes from other trophic groups were detected well but other eukaryotes were detected less consistently. DNA sampling errors or informatic errors or both were involved in misidentification of H. avenae; however, the proportions of each varied in the different bioinformatic pipelines and with different parameters used. To a large extent, false-positive and false-negative errors were complementary: pipelines and parameters with the highest false-positive rates had the lowest false-negative rates and vice versa. Sources of error identified included assumptions in the bioinformatic pipelines, slight differences in primer regions, the number of sequence reads regarded as the minimum threshold for inclusion in analysis

In planta processing and glycosylation of a nematode CLAVATA3/ENDOSPERM SURROUNDING REGION-like effector and its interaction with a host CLAVATA2-like receptor to promote parasitism.

Science.gov (United States)

Chen, Shiyan; Lang, Ping; Chronis, Demosthenis; Zhang, Sheng; De Jong, Walter S; Mitchum, Melissa G; Wang, Xiaohong

2015-01-01

Like other biotrophic plant pathogens, plant-parasitic nematodes secrete effector proteins into host cells to facilitate infection. Effector proteins that mimic plant CLAVATA3/ENDOSPERM SURROUNDING REGION-related (CLE) proteins have been identified in several cyst nematodes, including the potato cyst nematode (PCN); however, the mechanistic details of this cross-kingdom mimicry are poorly understood. Plant CLEs are posttranslationally modified and proteolytically processed to function as bioactive ligands critical to various aspects of plant development. Using ectopic expression coupled with nanoliquid chromatography-tandem mass spectrometry analysis, we show that the in planta mature form of proGrCLE1, a multidomain CLE effector secreted by PCN during infection, is a 12-amino acid arabinosylated glycopeptide (named GrCLE1-1Hyp4,7g) with striking structural similarity to mature plant CLE peptides. This glycopeptide is more resistant to hydrolytic degradation and binds with higher affinity to a CLAVATA2-like receptor (StCLV2) from potato (Solanum tuberosum) than its nonglycosylated forms. We further show that StCLV2 is highly up-regulated at nematode infection sites and that transgenic potatoes with reduced StCLV2 expression are less susceptible to PCN infection, indicating that interference of the CLV2-mediated signaling pathway confers nematode resistance in crop plants. These results strongly suggest that phytonematodes have evolved to utilize host cellular posttranslational modification and processing machinery for the activation of CLE effectors following secretion into plant cells and highlight the significance of arabinosylation in regulating nematode CLE effector activity. Our finding also provides evidence that multidomain CLEs are modified and processed similarly to single-domain CLEs, adding new insight into CLE maturation in plants. © 2015 American Society of Plant Biologists. All Rights Reserved.

Orthokeratinised odontogenic cyst mimicking periapical cyst.

Science.gov (United States)

Rajalakshmi, R; Sreeja, C; Vijayalakshmi, D; Leelarani, V

2013-10-07

Orthokeratinised odontogenic cyst (OOC) denotes the odontogenic cyst that microscopically has an orthokeratinised epithelial lining. OOC is characterised by a less-aggressive behaviour and a low rate of recurrence. This report describes a case of OOC involving posterior part of the mandible that mimicked periapical cyst in a 14-year-old boy. The initial clinical diagnosis was given as periapical cyst based on the clinical and radiographical features. Enucleation of the cyst was performed and the specimen was sent for histopathological examination. A definite diagnosis of OOC was made by histopathological examination of the biopsy specimen. This case emphases on including OOC in the differential diagnosis of radiolucencies occurring in the periapical region of non-vital tooth.

Biofumigation with Brassica juncea, Raphanus sativus and Eruca sativa for the management of field populations of the potato cyst nematode Globodera pallida.

Science.gov (United States)

Ngala, Bruno M; Haydock, Patrick P J; Woods, Simon; Back, Matthew A

2015-05-01

The viability of potato cyst nematode (PCN) populations (Globodera pallida) was evaluated in three field experiments using Brassica juncea, Raphanus sativus and Eruca sativa amendments. These species were summer cultivated and autumn incorporated in experiment 1; in experiment 2, overwintered brassicaceous cover crops were spring incorporated. Experiment 3 involved determination of effects of metconazole application on biomass/glucosinolate production by B. juncea and R. sativus and on PCN pre- and post-incorporation. Glucosinolate contents were determined before incorporation. Following cover crop incorporation, field plots were planted with susceptible potatoes to evaluate the biofumigation effects on PCN reproduction. In experiment 1, PCN population post-potato harvest was reduced (P = 0.03) in B. juncea-treated plots, while R. sativus prevented further multiplication, but in experiment 2 there were no significant effects on PCN reproduction. In experiment 3, B. juncea or R. sativus either untreated or treated with metconazole reduced PCN populations. Glucosinolate concentrations varied significantly between different plant regions and cultivation seasons. Metconazole application increased the sinigrin concentration in B. juncea tissues. Glucosinolate concentrations correlated positively with PCN mortality for summer-cultivated brassicaceous plants. The results demonstrated that B. juncea and R. sativus green manures can play an important role in PCN management, particularly if included in an integrated pest management scheme. © 2014 Society of Chemical Industry.

7 CFR 301.86-2 - Regulated articles.

Science.gov (United States)

2010-01-01

... SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Pale Cyst Nematode § 301.86-2 Regulated articles. The following are regulated articles: (a) Pale cyst nematodes.2 2 Permit and other requirements for the interstate movement of pale cyst nematodes are contained in part 330 of this chapter. (b) The...

7 CFR 301.86-3 - Quarantined areas.

Science.gov (United States)

2010-01-01

... SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Pale Cyst Nematode § 301.86-3 Quarantined... be infested with pale cyst nematode, each field that has been found to be associated with an infested... State as a quarantined area will prevent the interstate spread of the pale cyst nematode. (c) Criteria...

Host resistance in potato to three Globodera species

Science.gov (United States)

Potato cyst nematodes (PCN) under quarantine in the U.S. and Canada are the pale cyst nematode (Globodera pallida) and the golden cyst nematode (G. rostochiensis). A new species, G. ellingtonae was discovered in Oregon and Idaho in 2008 and is not currently a quarantine pest. In 2006 detection of ...

Simple bone cyst of mandible mimicking periapical cyst.

Science.gov (United States)

Hs, Charan Babu; Rai, Bhagawan Das; Nair, Manju A; Astekar, Madhusudan S

2012-05-29

Simple bone cysts (SBC) are pseudocysts occurring less commonly in the maxillofacial region. The uncertain and unclear etiopathogenesis led to numerous synonyms to refer this particular cyst. These cysts are devoid of an epithelial lining and are usually empty or contain blood or straw-colored fluid. In jaws initially it mimics a periapical cyst and later can lead to cortical bone expansion warranting for radical approach, which is seldom required. SBC is predominantly diagnosed in first two decades of life. Here we report a case of solitary bone cyst mimicking a periapical cyst of a mandibular molar in a 37-year-old patient.

Cryphodera sinensis n. sp. (Nematoda: Heteroderidae), a non-cyst-forming parasitic nematode from the root of ramie Boehmeria nivea in China.

Science.gov (United States)

Zhuo, K; Wang, H H; Ye, W; Peng, D L; Liao, J L

2014-12-01

Cryphodera sinensis n. sp. is described from ramie (Boehmeria nivea) based on the morphology and molecular analyses of rRNA small subunit (SSU), D2D3 expansion domains of large subunit (LSU D2D3) and internal transcribed spacer (ITS). This new species is characterized by oval females with a distinct subcrystalline layer and pronounced and protruding vulval lip, distinctly concave vulva-anus profile and a vulva-anus distance of 29.5-35.8 μm. Males possess two annuli in the lip region, a stylet 27-32.5 μm in length with round knobs sloping slightly posteriorly, lateral fields with three lines, spicules 20-28 μm long and the presence of a short cloacal tube. Second-stage juveniles possess three lip annuli, a stylet 28-31 μm in length with well-developed knobs projected anteriorly and three lines along the lateral field. The pointed tail, 52-65 μm long, possesses a mucro-like tip and a hyaline region, 24.5-35 μm long. Large phasmids with a lens-like structure are located 2-6 annuli posterior to the anus. Phylogenetic analysis shows that the species has unique SSU, LSU D2D3 and ITS rRNA sequences. Phylogenetic relationships of the three rDNA sequences of C. sinensis n. sp. and other cystoid/cyst nematodes are analysed together with a comparison of other species within the genus Cryphodera.

Conjoint effect of oil-seed cakes and Pseudomonas fluorescens on the growth of chickpea in relation to the management of plant-parasitic nematodes

Directory of Open Access Journals (Sweden)

Rose Rizvi

2012-12-01

Full Text Available Soil application of organics has been explored as an alternative means of organic management of plant-parasitic nematodes. Efficiency of different oil-seed cakes of neem (Azadirachta indica, castor (Ricinus communis, groundnut (Arachis hypogaea, linseed (Linum usitatissimum, sunflower (Helianthus annuus and soybean (Glycine max were evaluated in field conditions with association of Pseudomonas fluorescens in relation to growth parameters of chickpea and population of plant-parasitic nematodes. Their efficacious nature was highly effective in reducing the population of these dominant soil nematodes. Significant improvement was observed in plant-growth parameters such as plant weight, percent pollen fertility, pod numbers, root-nodulation and chlorophyll content of chickpea, seemed to be due to reduction in disease incidence and might be due to growth promoting substances secreted by P. fluorescens. The multiplication rate of nematodes was less in the presence of P. fluorescens as compared to its absence. Most effective combination of P. fluorescens was observed with neem cake.

Effect of winter cover crops on nematode population levels in north Florida.

Science.gov (United States)

Wang, K-H; McSorley, R; Gallaher, R N

2004-12-01

Two experiments were conducted in north-central Florida to examine the effects of various winter cover crops on plant-parasitic nematode populations through time. In the first experiment, six winter cover crops were rotated with summer corn (Zea mays), arranged in a randomized complete block design. The cover crops evaluated were wheat (Triticum aestivum), rye (Secale cereale), oat (Avena sativa), lupine (Lupinus angustifolius), hairy vetch (Vicia villosa), and crimson clover (Trifolium incarnatum). At the end of the corn crop in year 1, population densities of Meloidogyne incognita were lowest on corn following rye or oat (P rye or lupine was planted into field plots with histories of five tropical cover crops: soybean (Glycine max), cowpea (Vigna unguiculata), sorghum-sudangrass (Sorghum bicolor x S. sudanense), sunn hemp (Crotalaria juncea), and corn. Population densities of M. incognita and Helicotylenchus dihystera were affected by previous tropical cover crops (P cover crops present at the time of sampling. Plots planted to sunn hemp in the fall maintained the lowest M. incognita and H. dihystera numbers. Results suggest that winter cover crops tested did not suppress plant-parasitic nematodes effectively. Planting tropical cover crops such as sunn hemp after corn in a triple-cropping system with winter cover crops may provide more versatile nematode management strategies in northern Florida.

7 CFR 301.86-1 - Definitions.

Science.gov (United States)

2010-01-01

..., DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Pale Cyst Nematode § 301.86-1 Definitions... been found to be at risk for infestation with pale cyst nematode in accordance with § 301.86-3(c)(2... specified regulated article is free of pale cyst nematode and may be moved interstate to any destination...

Association analysis of resistance to cereal cyst nematodes (Heterodera avenae) and root lesion nematodes (Pratylenchus neglectus and P. thornei) in CIMMYT advanced spring wheat lines for semi-arid conditions.

Science.gov (United States)

Dababat, Abdelfattah A; Ferney, Gomez-Becerra Hugo; Erginbas-Orakci, Gul; Dreisigacker, Susanne; Imren, Mustafa; Toktay, Halil; Elekcioglu, Halil I; Mekete, Tesfamariam; Nicol, Julie M; Ansari, Omid; Ogbonnaya, Francis

2016-12-01

To identify loci linked to nematode resistance genes, a total of 126 of CIMMYT advanced spring wheat lines adapted to semi-arid conditions were screened for resistance to Heterodera avenae , Pratylenchus neglectus , and P. thornei , of which 107 lines were genotyped with 1,310 DArT. Association of DArT markers with nematode response was analyzed using the general linear model. Results showed that 11 markers were associated with resistance to H. avenae (pathotype Ha21), 25 markers with resistance to P. neglectus , and 9 significant markers were identified to be linked with resistance to P. thornei . In this work we confirmed that chromosome 4A (~90-105 cM) can be a source of resistance to P. thornei as has been recently reported. Other significant markers were also identified on chromosomal regions where no resistant genes have been reported for both nematodes species. These novel QTL were mapped to chromosomes 5A, 6A, and 7A for H. avenae ; on chromosomes 1A, 1B, 3A, 3B, 6B, 7AS, and 7D for P. neglectus ; and on chromosomes 1D, 2A, and 5B for P. thornei and represent potentially new loci linked to resistance that may be useful for selecting parents and deploying resistance into elite germplasm adapted to regions where nematodes are causing problem.

The cyst nematode SPRYSEC protein RBP-1 elicits Gpa2- and RanGAP2-dependent plant cell death.

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Melanie Ann Sacco

2009-08-01

Full Text Available Plant NB-LRR proteins confer robust protection against microbes and metazoan parasites by recognizing pathogen-derived avirulence (Avr proteins that are delivered to the host cytoplasm. Microbial Avr proteins usually function as virulence factors in compatible interactions; however, little is known about the types of metazoan proteins recognized by NB-LRR proteins and their relationship with virulence. In this report, we demonstrate that the secreted protein RBP-1 from the potato cyst nematode Globodera pallida elicits defense responses, including cell death typical of a hypersensitive response (HR, through the NB-LRR protein Gpa2. Gp-Rbp-1 variants from G. pallida populations both virulent and avirulent to Gpa2 demonstrated a high degree of polymorphism, with positive selection detected at numerous sites. All Gp-RBP-1 protein variants from an avirulent population were recognized by Gpa2, whereas virulent populations possessed Gp-RBP-1 protein variants both recognized and non-recognized by Gpa2. Recognition of Gp-RBP-1 by Gpa2 correlated to a single amino acid polymorphism at position 187 in the Gp-RBP-1 SPRY domain. Gp-RBP-1 expressed from Potato virus X elicited Gpa2-mediated defenses that required Ran GTPase-activating protein 2 (RanGAP2, a protein known to interact with the Gpa2 N terminus. Tethering RanGAP2 and Gp-RBP-1 variants via fusion proteins resulted in an enhancement of Gpa2-mediated responses. However, activation of Gpa2 was still dependent on the recognition specificity conferred by amino acid 187 and the Gpa2 LRR domain. These results suggest a two-tiered process wherein RanGAP2 mediates an initial interaction with pathogen-delivered Gp-RBP-1 proteins but where the Gpa2 LRR determines which of these interactions will be productive.

Simple bone cyst of mandible mimicking periapical cyst

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Charan Babu HS

2012-05-01

Full Text Available Simple bone cysts (SBC are pseudocysts occurring less commonly in the maxillofacial region. The uncertain and unclear etiopathogenesis led to numerous synonyms to refer this particular cyst. These cysts are devoid of an epithelial lining and are usually empty or contain blood or straw-colored fluid. In jaws initially it mimics a periapical cyst and later can lead to cortical bone expansion warranting for radical approach, which is seldom required. SBC is predominantly diagnosed in first two decades of life. Here we report a case of solitary bone cyst mimicking a periapical cyst of a mandibular molar in a 37-year-old patient.

Tropical rotation crops influence nematode densities and vegetable yields.

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McSorley, R; Dickson, D W; de Brito, J A; Hochmuth, R C

1994-09-01

The effects of eight summer rotation crops on nematode densities and yields of subsequent spring vegetable crops were determined in field studies conducted in north Florida from 1991 to 1993. The crop sequence was as follows: (i) rotation crops during summer 1991; (ii) cover crop of rye (Secale cereale) during winter 1991-92; (iii) 'Lemondrop L' squash (Cucurbita pepo) during spring 1992; (iv) rotation crops during summer 1992; (v) rye during winter 1992-93; (vi) 'Classic' eggplant (Solanum melongena) during spring 1993. The eight summer crop rotation treatments were as follows: 'Hale' castor (Ricinus communis), velvetbean (Mucuna deeringiana), sesame (Sesamum indicum), American jointvetch (Aeschynomene americana), weed fallow, 'SX- 17' sorghum-sudangrass (Sorghum bicolor x S. sudanense), 'Kirby' soybean (Glycine max), and 'Clemson Spineless' okra (Hibiscus esculentus) as a control. Rotations with castor, velvetbean, American jointvetch, and sorghum-sudangrass were most effective in maintaining the lowest population densities of Meloidogyne spp. (a mixture of M. incognita race 1 and M. arenaria race 1), but Paratrichodorus minor built up in the sorghum-sudangrass rotation. Yield of squash was lower (P crops evaluated here may be useful for managing nematodes in the field and for improving yields of subsequent vegetable crops.

The relationship between temperature and development in Globodera ellingtonae

Science.gov (United States)

A new cyst nematode species, Globodera ellingtonae, was recently described from populations in Oregon and Idaho; this nematode has been shown to reproduce on potato. Because of this nematodes close relationship to the potato cyst nematodes, G. rostochiensis and G. pallida, an understanding of the ri...

Nematode-Trapping Fungi.

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Jiang, Xiangzhi; Xiang, Meichun; Liu, Xingzhong

2017-01-01

Nematode-trapping fungi are a unique and intriguing group of carnivorous microorganisms that can trap and digest nematodes by means of specialized trapping structures. They can develop diverse trapping devices, such as adhesive hyphae, adhesive knobs, adhesive networks, constricting rings, and nonconstricting rings. Nematode-trapping fungi have been found in all regions of the world, from the tropics to Antarctica, from terrestrial to aquatic ecosystems. They play an important ecological role in regulating nematode dynamics in soil. Molecular phylogenetic studies have shown that the majority of nematode-trapping fungi belong to a monophyletic group in the order Orbiliales (Ascomycota). Nematode-trapping fungi serve as an excellent model system for understanding fungal evolution and interaction between fungi and nematodes. With the development of molecular techniques and genome sequencing, their evolutionary origins and divergence, and the mechanisms underlying fungus-nematode interactions have been well studied. In recent decades, an increasing concern about the environmental hazards of using chemical nematicides has led to the application of these biological control agents as a rapidly developing component of crop protection.

Origin and genetic diversity of Western European populations of the potato cyst nematode (Globodera pallida) inferred from mitochondrial sequences and microsatellite loci.

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Plantard, O; Picard, D; Valette, S; Scurrah, M; Grenier, E; Mugniéry, D

2008-05-01

Native to South America, the potato cyst nematode Globodera pallida is one of the principal pests of Andean potato crops and is also an important global pest following its introduction to Europe, Africa, North America, Asia and Oceania. Building on earlier work showing a clear south to north phylogeographic pattern in Peruvian populations, we have been able to identify the origin of Western European populations with high accuracy. They are all derived from a single restricted area in the extreme south of Peru, located between the north shore of the Lake Titicaca and Cusco. Only four cytochrome b haplotypes are found in Western Europe, one of them being also found in some populations of this area of southern Peru. The allelic richness at seven microsatellite loci observed in the Western European populations, although only one-third of that observed in this part of southern Peru, is comparable to the allelic richness observed in the northern region of Peru. This result could be explained by the fact that most of the genetic variability observed at the scale of a field or even of a region is already observed at the scale of a single plant within a field. Thus, even introduction via a single infected potato plant could result in the relatively high genetic variability observed in Western Europe. This finding has important consequences for the control of this pest and the development of quarantine measures.

Soybean supplementation increases the resilience of microbial and nematode communities in soil to extreme rainfall in an agroforestry system.

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Sun, Feng; Pan, Kaiwen; Li, Zilong; Wang, Sizhong; Tariq, Akash; Olatunji, Olusanya Abiodun; Sun, Xiaoming; Zhang, Lin; Shi, Weiyu; Wu, Xiaogang

2018-06-01

A current challenge for ecological research in agriculture is to identify ways in which to improve the resilience of the soil food web to extreme climate events, such as severe rainfall. Plant species composition influence soil biota communities differently, which might affect the recovery of soil food web after extreme rainfall. We compared the effects of rainfall stress up on the soil microbial food web in three planting systems: a monoculture of the focal species Zanthoxylum bungeanum and mixed cultures of Z. bungeanum and Medicago sativa or Z. bungeanum and Glycine max. We tested the effect of the presence of a legume on the recovery of trophic interactions between microorganisms and nematodes after extreme rainfall. Our results indicated that all chemical properties of the soil recovered to control levels (normal rainfall) in the three planting systems 45 days after exposure to extreme rain. However, on day 45, the bulk microbial community differed from controls in the monoculture treatment, but not in the two mixed planting treatments. The nematode community did not fully recover in the monoculture or Z. bungeanum and M. sativa treatments, while nematode populations in the combined Z. bungeanum and G. max treatment were indistinguishable from controls. G. max performed better than M. sativa in terms of increasing the resilience of microbial and nematode communities to extreme rainfall. Soil microbial biomass and nematode density were positively correlated with the available carbon and nitrogen content in soil, demonstrating a link between soil health and biological properties. This study demonstrated that certain leguminous plants can stabilize the soil food web via interactions with soil biota communities after extreme rainfall. Copyright © 2018 Elsevier B.V. All rights reserved.

The Role of Programmed Cell Death Regulator LSD1 in Nematode-Induced Syncytium Formation

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Mateusz Matuszkiewicz

2018-03-01

Full Text Available Cyst-forming plant-parasitic nematodes are common pests of many crops. They inject secretions into host cells to induce the developmental and metabolic reprogramming that leads to the formation of a syncytium, which is the sole food source for growing nematodes. As in other host-parasite models, avirulence leads to rapid and local programmed cell death (PCD known as the hypersensitive response (HR, whereas in the case of virulence, PCD is still observed but is limited to only some cells. Several regulators of PCD were analyzed to understand the role of PCD in compatible plant–nematode interactions. Thus, Arabidopsis plants carrying recessive mutations in LESION SIMULATING DISEASE1 (LSD1 family genes were subjected to nematode infection assays with juveniles of Heterodera schachtii. LSD1 is a negative and conditional regulator of PCD, and fewer and smaller syncytia were induced in the roots of lsd1 mutants than in wild-type Col-0 plants. Mutation in LSD ONE LIKE2 (LOL2 revealed a pattern of susceptibility to H. schachtii antagonistic to lsd1. Syncytia induced on lsd1 roots compared to Col0 showed significantly retarded growth, modified cell wall structure, increased vesiculation, and some myelin-like bodies present at 7 and 12 days post-infection. To place these data in a wider context, RNA-sequencing analysis of infected and uninfected roots was conducted. During nematode infection, the number of transcripts with changed expression in lsd1 was approximately three times smaller than in wild-type plants (1440 vs. 4206 differentially expressed genes, respectively. LSD1-dependent PCD in roots is thus a highly regulated process in compatible plant–nematode interactions. Two genes identified in this analysis, coding for AUTOPHAGY-RELATED PROTEIN 8F and 8H were down-regulated in syncytia in the presence of LSD1 and showed an increased susceptibility to nematode infection contrasting with lsd1 phenotype. Our data indicate that molecular regulators

The Role of Programmed Cell Death Regulator LSD1 in Nematode-Induced Syncytium Formation

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Matuszkiewicz, Mateusz; Sobczak, Miroslaw; Cabrera, Javier; Escobar, Carolina; Karpiński, Stanislaw; Filipecki, Marcin

2018-01-01

Cyst-forming plant-parasitic nematodes are common pests of many crops. They inject secretions into host cells to induce the developmental and metabolic reprogramming that leads to the formation of a syncytium, which is the sole food source for growing nematodes. As in other host-parasite models, avirulence leads to rapid and local programmed cell death (PCD) known as the hypersensitive response (HR), whereas in the case of virulence, PCD is still observed but is limited to only some cells. Several regulators of PCD were analyzed to understand the role of PCD in compatible plant–nematode interactions. Thus, Arabidopsis plants carrying recessive mutations in LESION SIMULATING DISEASE1 (LSD1) family genes were subjected to nematode infection assays with juveniles of Heterodera schachtii. LSD1 is a negative and conditional regulator of PCD, and fewer and smaller syncytia were induced in the roots of lsd1 mutants than in wild-type Col-0 plants. Mutation in LSD ONE LIKE2 (LOL2) revealed a pattern of susceptibility to H. schachtii antagonistic to lsd1. Syncytia induced on lsd1 roots compared to Col0 showed significantly retarded growth, modified cell wall structure, increased vesiculation, and some myelin-like bodies present at 7 and 12 days post-infection. To place these data in a wider context, RNA-sequencing analysis of infected and uninfected roots was conducted. During nematode infection, the number of transcripts with changed expression in lsd1 was approximately three times smaller than in wild-type plants (1440 vs. 4206 differentially expressed genes, respectively). LSD1-dependent PCD in roots is thus a highly regulated process in compatible plant–nematode interactions. Two genes identified in this analysis, coding for AUTOPHAGY-RELATED PROTEIN 8F and 8H were down-regulated in syncytia in the presence of LSD1 and showed an increased susceptibility to nematode infection contrasting with lsd1 phenotype. Our data indicate that molecular regulators belonging to the

Genome scans on experimentally evolved populations reveal candidate regions for adaptation to plant resistance in the potato cyst nematode Globodera pallida.

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Eoche-Bosy, D; Gautier, M; Esquibet, M; Legeai, F; Bretaudeau, A; Bouchez, O; Fournet, S; Grenier, E; Montarry, J

2017-09-01

Improving resistance durability involves to be able to predict the adaptation speed of pathogen populations. Identifying the genetic bases of pathogen adaptation to plant resistances is a useful step to better understand and anticipate this phenomenon. Globodera pallida is a major pest of potato crop for which a resistance QTL, GpaV vrn , has been identified in Solanum vernei. However, its durability is threatened as G. pallida populations are able to adapt to the resistance in few generations. The aim of this study was to investigate the genomic regions involved in the resistance breakdown by coupling experimental evolution and high-density genome scan. We performed a whole-genome resequencing of pools of individuals (Pool-Seq) belonging to G. pallida lineages derived from two independent populations having experimentally evolved on susceptible and resistant potato cultivars. About 1.6 million SNPs were used to perform the genome scan using a recent model testing for adaptive differentiation and association to population-specific covariables. We identified 275 outliers and 31 of them, which also showed a significant reduction in diversity in adapted lineages, were investigated for their genic environment. Some candidate genomic regions contained genes putatively encoding effectors and were enriched in SPRYSECs, known in cyst nematodes to be involved in pathogenicity and in (a)virulence. Validated candidate SNPs will provide a useful molecular tool to follow frequencies of virulence alleles in natural G. pallida populations and define efficient strategies of use of potato resistances maximizing their durability. © 2017 John Wiley & Sons Ltd.

Macrophage polarization differs between apical granulomas, radicular cysts, and dentigerous cysts.

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Weber, Manuel; Schlittenbauer, Tilo; Moebius, Patrick; Büttner-Herold, Maike; Ries, Jutta; Preidl, Raimund; Geppert, Carol-Immanuel; Neukam, Friedrich W; Wehrhan, Falk

2018-01-01

Apical periodontitis can appear clinically as apical granulomas or radicular cysts. There is evidence that immunologic factors are involved in the pathogenesis of both pathologies. In contrast to radicular cysts, the dentigerous cysts have a developmental origin. Macrophage polarization (M1 vs M2) is a main regulator of tissue homeostasis and differentiation. There are no studies comparing macrophage polarization in apical granulomas, radicular cysts, and dentigerous cysts. Forty-one apical granulomas, 23 radicular cysts, and 23 dentigerous cysts were analyzed in this study. A tissue microarray (TMA) of the 87 consecutive specimens was created, and CD68-, CD11c-, CD163-, and MRC1-positive macrophages were detected by immunohistochemical methods. TMAs were digitized, and the expression of macrophage markers was quantitatively assessed. Radicular cysts are characterized by M1 polarization of macrophages while apical granulomas show a significantly higher degree of M2 polarization. Dentigerous cysts have a significantly lower M1 polarization than both analyzed periapical lesions (apical granulomas and radicular cysts) and accordingly, a significantly higher M2 polarization than radicular cysts. Macrophage cell density in dentigerous cysts is significantly lower than in the periapical lesions. The development of apical periodontitis towards apical granulomas or radicular cysts might be directed by macrophage polarization. Radicular cyst formation is associated with an increased M1 polarization of infiltrating macrophages. In contrast to radicular cysts, dentigerous cysts are characterized by a low macrophage infiltration and a high degree of M2 polarization, possibly reflecting their developmental rather than inflammatory origin. As M1 polarization of macrophages is triggered by bacterial antigens, these results underline the need for sufficient bacterial clearance during endodontic treatment to prevent a possible M1 macrophage-derived stimulus for radicular cyst

Simple bone cyst of mandible mimicking periapical cyst

OpenAIRE

Charan Babu HS; Bhagawan Das Rai; Manju A. Nair; Madhusudan S. Astekar

2012-01-01

Simple bone cysts (SBC) are pseudocysts occurring less commonly in the maxillofacial region. The uncertain and unclear etiopathogenesis led to numerous synonyms to refer this particular cyst. These cysts are devoid of an epithelial lining and are usually empty or contain blood or straw-colored fluid. In jaws initially it mimics a periapical cyst and later can lead to cortical bone expansion warranting for radical approach, which is seldom required. SBC is predominantly diagnosed in first two ...

Bulviniai cistiniai nematodai Globodera rostochiensis ir Globodera pallida, jų chemoekologinių sąveikų su augalu šeimininku tyrimas

OpenAIRE

Čepulytė-Rakauskienė, Rasa

2012-01-01

Potato cyst nematodes Globodera rostochiensis and Globodera pallida are one of the most important solanaceous plant pests. Identification of potato cyst nematodes species is exposed to morphological similarities and overlapping morphometric measurements between species. Only modern molecular techniques allow more accurate identification of potato cyst nematode species. Hence, it is important to apply these techniques in order to reliably identify these species in Lithuania. Potato roots...

Effects of root herbivory by nematodes on the performance and preference of a leaf-infesting generalist aphid depend on nitrate fertilization.

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Kutyniok, Magdalene; Persicke, Marcus; Müller, Caroline

2014-02-01

The performance and behavior of herbivores is strongly affected by the quality of their host plants, which is determined by various environmental conditions. We investigated the performance and preference of the polyphagous shoot-infesting aphid Myzus persicae on the host-plant Arabidopsis thaliana in a two-factorial design in which nitrate fertilization was varied by 33 %, and the root-infesting cyst-nematode Heterodera schachtii was present or absent. Aphid performance was influenced by these abiotic and biotic factors in an interactive way. Nematode presence decreased aphid performance when nitrate levels were low, whereas nematode infestation did not influence aphid performance under higher nitrate fertilization. Aphids followed the "mother knows best" principle when given a choice, settling preferentially on those plants on which they performed best. Hence, they preferred nematode-free over nematode-infested plants in the low fertilization treatment but host choice was not affected by nematodes under higher nitrate fertilization. The amino acid composition of the phloem exudates was significantly influenced by fertilization but also by the interaction of the two treatments. Various glucosinolates in the leaves, which provide an estimate of phloem glucosinolates, were not affected by the individual treatments but by the combination of fertilization and herbivory. These changes in primary and secondary metabolites may be decisive for the herbivore responses. Our data demonstrate that abiotic and biotic factors can interactively affect herbivores, adding a layer of complexity to plant-mediated herbivore interactions.

Toxicity of manipueira to Meloidogyne incognita in soybean

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Wéverson Lima Fonseca

2016-12-01

Full Text Available Manipueira, a liquid residue obtained from the cassava industrialization, shows high toxicity to the microbial diversity. This study aimed at evaluating the potential of manipueira applied to the soil to control Meloidogyne incognita in soybean. A completely randomized design, in a 2 x 11 factorial scheme, was used, consisting of two application forms of manipueira (single and two applications, in eleven concentrations (0 %, 10 %, 20 %, 30 %, 40 %, 50 %, 60 %, 70 %, 80 %, 90 % and 100 %, with five replications per treatment. Some agronomic traits and parasitism characteristics were also evaluated. The plants that received a single application of manipueira showed a gain of 100.41 % in root length, while the volume and fresh root mass showed gains of 81.52 % and 28.11 %, respectively, with the two applications. Regarding parasitism, the single application was more effective in reducing the number of juveniles in the soil and roots, where the concentrations of manipueira to kill 50 % of the nematodes were 1.65 % and 4.37 %, respectively. Thus, besides being effective in controlling M. incognita, manipueira has a positive effect on the development of soybean and may be recommended as a nematicide and also as an organic fertilizer.

Developmental dynamics of Globodera ellingtonae in field-grown potato

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Globodera ellingtonae is a recently described nematode parasite of potato, which is closely related to the economically-significant potato cyst nematodes, G. rostochiensis and G. pallida. Because of the close relationship of G. ellingtonae to the potato cyst nematodes, a greater understanding of its...

Predator-prey interactions of nematode-trapping fungi and nematodes: both sides of the coin.

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Vidal-Diez de Ulzurrun, Guillermo; Hsueh, Yen-Ping

2018-05-01

Nematode-trapping fungi develop complex trapping devices to capture and consume nematodes. The dynamics of these organisms is especially important given the pathogenicity of nematodes and, consequently, the potential application of nematode-trapping fungi as biocontrol agents. Furthermore, both the nematodes and nematode-trapping fungi can be easily grown in laboratories, making them a unique manipulatable predator-prey system to study their coevolution. Several different aspects of these fungi have been studied, such as their genetics and the different factors triggering trap formation. In this review, we use the nematode-trapping fungus Arthrobotrys oligospora (which forms adhesive nets) as a model to describe the trapping process. We divide this process into several stages; namely attraction, recognition, trap formation, adhesion, penetration, and digestion. We summarize the latest findings in the field and current knowledge on the interactions between nematodes and nematode-trapping fungi, representing both sides of the predator-prey interaction.

EVALUATION OF SOYBEAN CULTIVARS AND LINES RESISTANCE TO Pratylenchus brachyurus AVALIAÇÃO DA RESISTÊNCIA DE CULTIVARES E LINHAGENS DE SOJA A Pratylenchus brachyurus

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Dilson da Cunha Costa

2007-09-01

Full Text Available

Pratylenchus brachyurus, a plant parasitic nematode which has wide distribution due to a broad range of hosts, causes damages to soybean all over the world. Chlorosis and dwarfing in soybean plants are very common symptoms associated with this nematode infestation. The present work had as objective to evaluate the resistance of soybean cultivars and lines to P. brachyurus. Seeds of all genotypes were treated with a mixture of alcohol, sodium hypochloride, water (1:2:7. Pre-germinated seedlings were inoculated with 450 nematodes and, after 50 days under greenhouse conditions, the plants were harvested, when nematode number per root system and reproduction factors were evaluated. All genotypes tested were found to be infested with the nematode. However, 18.52% of the genotypes showed high susceptibility, 45.68% were susceptible, while 34.57% showed slight resistance and 1.23% were moderate resistant to the attack of P. brachyurus.

KEY-WORDS: Glycine max; root-lesion; nematode.

Pratylenchus brackyurus, que tem larga distribuição geográfica devido ao grande número de hospedeiros, causa prejuízos à soja em todo o mundo. Clorose e nanismo em plantas de soja são sintomas muito comuns associados à infestação desse nematóide. O presente trabalho teve por objetivo avaliara a resistência de cultivares e linhagens de soja a P. bhrachyurus. As sementes dos genótipos foram tratadas com uma mistura de álcool, hipoclorito de sódio e água (1:2:7 e pré-germinadas. Cada plântula foi inoculada com 450 juvenis e/ou adultos de P. brachyurus e, após 50 dias em casa de vegetação, as plantas foram colhidas, avaliando-se o número de nematóides por sistema radicular e os fatores de reprodução. A

Cerebral Arachnoid Cysts

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Ersin Haciyakupoglu

2016-09-01

Full Text Available Arachnoid cysts can occur through inflammatory, traumatic, chemical irritation, skin tumor and postoperative processes. It is diagnosed and differentiated by magnetic resonance imaging and computerized tomography from other lesions. Its differential diagnosis includes colloid cyst , craniopharyngioma, prosencephaly, holoprosencephaly , epidermoid cyst, hydatid cyst, low grade glial tumors, infarcts and subdural hygroma. Most of them are asymptomatic and diagnosed incidentally. Treatment methods such as simple cyst aspiration , total excision of the cyst, basal cysternostomy, ventricular fenestration, cysto or ventriculoperitoneal shunt can be performed by various endoscopic surgery and craniotomy. [Archives Medical Review Journal 2016; 25(3.000: 259-268

Extracellular Protease of Pseudomonas fluorescens CHA0, a Biocontrol Factor with Activity against the Root-Knot Nematode Meloidogyne incognita

OpenAIRE

Siddiqui, Imran Ali; Haas, Dieter; Heeb, Stephan

2005-01-01

In Pseudomonas fluorescens CHA0, mutation of the GacA-controlled aprA gene (encoding the major extracellular protease) or the gacA regulatory gene resulted in reduced biocontrol activity against the root-knot nematode Meloidogyne incognita during tomato and soybean infection. Culture supernatants of strain CHA0 inhibited egg hatching and induced mortality of M. incognita juveniles more strongly than did supernatants of aprA and gacA mutants, suggesting that AprA protease contributes to biocon...

Molecular mechanisms of nematode-nematophagous microbe interactions: basis for biological control of plant-parasitic nematodes.

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Li, Juan; Zou, Chenggang; Xu, Jianping; Ji, Xinglai; Niu, Xuemei; Yang, Jinkui; Huang, Xiaowei; Zhang, Ke-Qin

2015-01-01

Plant-parasitic nematodes cause significant damage to a broad range of vegetables and agricultural crops throughout the world. As the natural enemies of nematodes, nematophagous microorganisms offer a promising approach to control the nematode pests. Some of these microorganisms produce traps to capture and kill the worms from the outside. Others act as internal parasites to produce toxins and virulence factors to kill the nematodes from within. Understanding the molecular basis of microbe-nematode interactions provides crucial insights for developing effective biological control agents against plant-parasitic nematodes. Here, we review recent advances in our understanding of the interactions between nematodes and nematophagous microorganisms, with a focus on the molecular mechanisms by which nematophagous microorganisms infect nematodes and on the nematode defense against pathogenic attacks. We conclude by discussing several key areas for future research and development, including potential approaches to apply our recent understandings to develop effective biocontrol strategies.

A Standardized Method to Assess Infection Rates of Root-Knot and Cyst Nematodes in Arabidopsis thaliana Mutants with Alterations in Root Development Related to Auxin and Cytokinin Signaling.

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Olmo, Rocío; Silva, Ana Cláudia; Díaz-Manzano, Fernando E; Cabrera, Javier; Fenoll, Carmen; Escobar, Carolina

2017-01-01

Plant parasitic nematodes cause a great impact in agricultural systems. The search for effective control methods is partly based on the understanding of underlying molecular mechanisms leading to the formation of nematode feeding sites. In this respect, crosstalk of hormones such as auxins and cytokinins (IAA, CK) between the plant and the nematode seems to be crucial. Thence, the study of loss of function or overexpressing lines with altered IAA and CK functioning is entailed. Those lines frequently show developmental defects in the number, position and/or length of the lateral roots what could generate a bias in the interpretation of the nematode infection parameters. Here we present a protocol to assess differences in nematode infectivity with the lowest interference of root architecture phenotypes in the results. Thus, tailored growth conditions and normalization parameters facilitate the standardized phenotyping of nematode infection.

Biology and predatory attributes of a diplogasterid nematode, Fictor composticola Khan et al., 2008

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Bajaj H. K.

2015-02-01

Full Text Available Biology of Fictor composticola has been studied on Aphelenchus avenae in vitro. It reproduces by amphimixis, embryonic development is completed in 24 - 27 h and life cycle in 3 - 4 days. Fusion of sperm and egg pronuclei occurs in the uteri. Pulsation of median oesophageal bulb and pressing of lips against egg shell is seen just prior to hatching but teeth seem to play no role in this process. No moulting occurs inside the egg shell and the first stage juvenile hatches out. Female and male undergo mating upon addition of water in the culture plates and continue to swim in copula for a considerable time. A female lays 1.6 - 4.0 eggs in 24 h while feeding upon A. radicicolus. Predation and reproduction is affected by the temperature and 25 - 35 °C is the optimum range for these phenomena. Process of feeding as recorded with a CCTV attached to a compound microscope is described. F. composticola engulfs small preys; sucks the intestinal contents while holding them or cuts the body wall of large-sized preys and then feeds on prolapsed organs. Two sexes differ in their efficiencies of predation, a female on an average kills 53 A. avenae as compared to 11 by a male in 24 h. F. composticola feeds and reproduces on mycophagous nematodes and juveniles of root- knot, cyst and citrus nematodes but does not prey upon adult nematodes having coarsely annulated cuticle. Cannibalism in this species is also observed. F. composticola and Seinura paratenuicaudata prey upon each other. Biocontrol potential of F. composticola for managing nematode problems in button mushroom and agricultural crops has also been discussed.

[Rare location of arachnoid cysts. Extratemporal cysts].

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Martinez-Perez, Rafael; Hinojosa, José; Pascual, Beatriz; Panaderos, Teresa; Welter, Diego; Muñoz, María J

2016-01-01

The therapeutic management of arachnoid cysts depends largely on its location. Almost 50% of arachnoid cysts are located in the temporal fossa-Sylvian fissure, whereas the other half is distributed in different locations, sometimes exceptional. Under the name of infrequent location arachnoid cysts, a description is presented of those composed of 2 sheets of arachnoid membrane, which are not located in the temporal fossa, and are primary or congenital. Copyright © 2015 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

ANALYSIS IMPORT POLICY OF SOYBEAN ON ECONOMICS PERFORMANCE OF INDONESIAN SOYBEAN

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Muthiah Abda Azizah

2015-11-01

Full Text Available Trade liberalization is closely related to the opening of market access for Indonesian products to the world and vice versa. Since the soybean trade out of BULOG control began in 1998, soybean imports increased very rapidly (Sudaryanto and Swastika, 2007. This research aims to determine the general picture of soybean economy, factors analyses that influence the economic performance of Indonesian soybean and findings the alternative of policies that can reduce soybean imports in Indonesia. Methods of data analysis are descriptive analysis, 2SLS simultaneous equations, and simulation of policy alternatives. Results of the analysis of the factors that affect the economic performance of Indonesian soybean, consists of 1 The area of soybean harvest is influenced significantly by the price of domestic soybean and domestic prices of corn, 2 Productivity soybean influenced significantly by the domestic prices of soybean and fertilizer prices, 3 soybean demand influenced significantly by population, domestic prices of soybean, 4 domestic prices of soybean significantly affected by world prices of soybean, exchange rates, and soybean supply, 5 Imports of soybean influenced significantly by the domestic demand of soybean and soybean production. Therefore, policy scenarios should be made to reduce soybean imports, including by carrying out the expansion of soybean harvest policy, the policy of increasing the productivity of soybean, the policy of subsidizing the price of fertilizer.

Odontogenic Cysts and Neoplasms.

Science.gov (United States)

Bilodeau, Elizabeth Ann; Collins, Bobby M

2017-03-01

This article reviews a myriad of common and uncommon odontogenic cysts and tumors. The clinical presentation, gross and microscopic features, differential diagnosis, prognosis, and diagnostic pitfalls are addressed for inflammatory cysts (periapical cyst, mandibular infected buccal cyst/paradental cyst), developmental cysts (dentigerous, lateral periodontal, glandular odontogenic, orthokeratinized odontogenic cyst), benign tumors (keratocystic odontogenic tumor, ameloblastoma, adenomatoid odontogenic tumor, calcifying epithelial odontogenic tumor, ameloblastic fibroma and fibroodontoma, odontoma, squamous odontogenic tumor, calcifying cystic odontogenic tumor, primordial odontogenic tumor, central odontogenic fibroma, and odontogenic myxomas), and malignant tumors (clear cell odontogenic carcinoma, ameloblastic carcinoma, ameloblastic fibrosarcoma). Copyright © 2016 Elsevier Inc. All rights reserved.

In vitro toxicity and control of Meloidogyne incognita in soybean by rosemary extract

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Mônica Anghinoni Müller

2016-02-01

Full Text Available The control of nematodes in plants can be challenging, and there is a need for alternative, environmentally conscious methods for their management. The purpose of this study was to evaluate the effect of rosemary extract (Rosmarinus officinalis on the in vitro toxicity and control of Meloidogyne incognita in CD 206 and CD 215 soybean cultivars. Using an in vitro assay, 500 M. incognita eggs per plate were observed for 15 days after incubation with rosemary extract at concentrations of 1%, 5%, and 10%. Soybean plants were studied under greenhouse conditions, and starting at V3 stage, were sprayed weekly with the same concentration of rosemary extract for 64 days. Three days after the first treatment, each soybean plant was inoculated with 1800 eggs and 400 second-stage juveniles (J2. At the end of this essay, number of eggs and J2 in the roots and soil, number of galls, and the reproduction factor (RF were evaluated. Our results showed that in the in vitro assay, rosemary extract reduced the number of M. incognita eggs that hatched. Under greenhouse conditions, the CD 206 cultivar showed a 48% reduction in the number of galls, as well as fewer eggs in the soil and a lower RF. Similarly, in the CD 215 cultivar, the number of eggs was reduced and the RF was lower. These results indicate the potential for rosemary extract to control M. incognita in soybean crops.

Post-traumatic cysts and cyst-like lesions of bone

International Nuclear Information System (INIS)

Moore, T.E.; Travis, R.C.; Allen, B.C.; King, A.R.

1989-01-01

We describe two patients with cyst-like lesions of bone that developed at sites of healed or healing fractures. One case showed histological features of a unicameral bone cyst, which, to the best of our knowledge, is a previously unreported finding in a post-traumatic cyst. It is suggested that there are two principal clinical and radiological types of post-traumatic cyst, of which each of our cases represents an example: (1) asymtompatic transient cortical lesions, found only in children, and (2) more central expanding lesions, found in a wider age group and associated with pain, swelling, and pathological fractures. (orig.)

Post-traumatic cysts and cyst-like lesions of bone

Energy Technology Data Exchange (ETDEWEB)

Moore, T.E.; Travis, R.C.; Allen, B.C.; King, A.R.

1989-04-01

We describe two patients with cyst-like lesions of bone that developed at sites of healed or healing fractures. One case showed histological features of a unicameral bone cyst, which, to the best of our knowledge, is a previously unreported finding in a post-traumatic cyst. It is suggested that there are two principal clinical and radiological types of post-traumatic cyst, of which each of our cases represents an example: (1) asymtompatic transient cortical lesions, found only in children, and (2) more central expanding lesions, found in a wider age group and associated with pain, swelling, and pathological fractures. (orig.).

Extracellular Protease of Pseudomonas fluorescens CHA0, a Biocontrol Factor with Activity against the Root-Knot Nematode Meloidogyne incognita

Science.gov (United States)

Siddiqui, Imran Ali; Haas, Dieter; Heeb, Stephan

2005-01-01

In Pseudomonas fluorescens CHA0, mutation of the GacA-controlled aprA gene (encoding the major extracellular protease) or the gacA regulatory gene resulted in reduced biocontrol activity against the root-knot nematode Meloidogyne incognita during tomato and soybean infection. Culture supernatants of strain CHA0 inhibited egg hatching and induced mortality of M. incognita juveniles more strongly than did supernatants of aprA and gacA mutants, suggesting that AprA protease contributes to biocontrol. PMID:16151170

Control químico del Nematodo quiste Heterodera trifolii en clavel miniatura Chemical control of the cyst nematode, Heterodera trifolii in miniature carnation

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Marroquin Alicia

1991-12-01

three non fumigant nematicides Aldicarb, Carbofuranand Oxamyl, at three different times for the control of the nematode. The fumigants were more efficient than the non fumigant nematicides for the reduction of the population of the nematode in the soil. The best treatment was DD Methylisothiocianate with a 52% reduction of the viable cysts population and 38% reduction of the larvae population in the soil, a reduction of 15 daysin harvesting time, a 9% increase in yield and 19% increase in net income, as compared with the untreated control. Among the three nonfumigant nematicides, the best treatments were Aldicarb and Carbofuran applied atplanting time. Oxamyl applied 30 days afterplanting showed similar results. The cornbination of the fumigants with the non fumigant nematicides did not improuve the nematode control, yield and quality of the flowers. Combination of the two types of nematicides increased the production costs.

Periorbital dermoid cyst

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Nigwekar Shubhangi P, Gupte Chaitanya P, Chaudhari Sagar V, Kharche Prajakta S

2014-07-01

Full Text Available Dermoid cysts are a developmental benign choristomas, which are congenital lesions representing normal tissue/s in an abnormal location. These consist of ectodermal and mesodermal elements, lined with epithelium and contain hair with other skin structures. Periorbital dermoid cyst is commonly located at lateral one third of the eyebrow. It is asymptomatic however school going child suffers from social stigma. So its surgical excision for cosmetic purpose becomes necessary. Excision also prevents bony remoulding and recurrent inflammatory responses due to leakage of cyst contents. In this article we are presenting a six years old male child having periorbital dermoid in lateral right eyebrow. The intact dermoid cyst was excised surgically and sent for histopathological examination, which confirmed the diagnosis of dermoid cyst. We highlight the merits of early surgical intervention, even in an asymptomatic periorbital dermoid cyst.

Expression of Ki-67 in odontogenic cysts: A comparative study between odontogenic keratocysts, radicular cysts and dentigerous cysts.

Science.gov (United States)

Modi, Tapan G; Chalishazar, Monali; Kumar, Malay

2018-01-01

Odontogenic cysts are the most common cysts of the jaws and are formed from the remnants of the odontogenic apparatus. Among these odontogenic cysts, radicular cysts (RCs) (about 60% of all diagnosed jaw cysts), dentigerous cysts (DCs) (16.6% of all jaw cysts) and odontogenic keratocysts (OKCs) (11.2% of all developmental odontogenic cysts) are the most common. The behavior of any lesion is generally reflected by its growth potential. Growth potential is determined by measuring the cell proliferative activity. The cell proliferative activity is measured by various methods among which immunohistochemistry (IHC) is the commonly used technique. Most of the IHC studies on cell proliferation have been based on antibodies such as Ki-67 and proliferating cell nuclear antigen. In the present study, the total sample size comprised of 45 cases of odontogenic cysts, with 15 cases each of OKC, RC and DC. Here, an attempt is made to study immunohistochemical (streptavidin-biotin detection system HRP-DAB) method to assess the expression of Ki-67 in different layers of the epithelial lining of OKCs, RCs and DCs. Ki-67 positive cells were highest in epithelium of OKC as compared to DC and RC. The increased Ki-67 labeling index and its expression in suprabasal cell layers of epithelial lining in OKC and its correlation with suprabasal cell layers of epithelial lining in DC and RC could contribute toward its clinically aggressive behavior. OKC is of more significance to the oral pathologist and oral surgeon because of its specific histopathological features, high recurrence rate and aggressive behavior.

Simple Kidney Cysts

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... Solitary Kidney Your Kidneys & How They Work Simple Kidney Cysts What are simple kidney cysts? Simple kidney cysts are abnormal, fluid-filled ... that form in the kidneys. What are the kidneys and what do they do? The kidneys are ...

Identifikasi karakter morfologi nematoda sista pada tanaman jagung (Heterodera zeae di Indonesia

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Yuliantoro Baliadi

2012-02-01

Full Text Available Identification of nematode species is the fi rst step in the resolution of major nematological problems. Accurate identification of maize cyst nematode species is essential for more detailed research, particularly for it control measure. Although morphological observations by using the key characters of each nematode are suitable for identification purposes, the cyst nematodes could not beclearly identified based on it due to the wide variations. For the identification of the cyst nematode species, key characters relating to body surface, head, mouth, esophagus, tail as well as habitat and feeding habits was used in the present examination. Procedures for the permanent and temporary preparations of nematodes were used. The nematode specimens were observed under the microscope to confirm the key characters. Results of measurements and descriptions revealed that the cyst nematode collected from maize roots in Madura island have the same ambifenestrate as that of Heterodera zeae. The underbridge is short and thin and there is two layer of bullae arrangement in vulval cone, the first layer with four finger-like bullae located immediately below the underbridge and the second layer very randomly located below the fi rst one. These characteristics are of H. zeae. These complete of morphological identifications are a new report of H. zeae in Indonesia.

[Allelic state of the molecular marker for the golden nematode (Globodera rostochiensis) resistance gene H1 among Ukrainian and world cultivars of potato (Solanum tuberosum ssp. tuberosum)].

Science.gov (United States)

Karelov, A V; Pilipenko, L A; Kozub, N A; Bondus, R A; Borzykh, A U; Sozinov, I A; Blium, Ia B; Sozinov, A A

2013-01-01

The purpose of our investigation was determination of allelic state of the H1 resistance gene against the pathotypes Ro1 and Ro4 of golden potato cyst nematode (Globodera rostochiensis) among Ukrainian and world potato (Solanum tuberosum ssp. tuberosum) cultivars. The allelic condition of the TG689 marker was determined by PCR with DNA samples isolated from tubers of potato and primers, one pair of which flanks the allele-specific region and the other one was used for the control of DNA quality. Among analyzed 77 potato cultivars the allele of marker associated with the H1-type resistance was found in 74% of Ukrainian and 90% foreign ones although some of those cultivars proved to be susceptible to the golden potato nematode in field. The obtained data confirm the presence of H1-resistance against golden nematode pathotypes Ro1 and Ro4 among the Ukrainian potato cultivars and efficiency of the used marker within the accuracy that has been declared by its authors.

The novel GrCEP12 peptide from the plant-parasitic nematode Globodera rostochiensis suppresses flg22-mediated PTI.

Science.gov (United States)

Chen, Shiyan; Chronis, Demosthenis; Wang, Xiaohong

2013-09-01

The potato cyst nematode Globodera rostochiensis is a biotrophic pathogen that secretes effector proteins into host root cells to promote successful plant parasitism. In addition to the role in generating within root tissue the feeding cells essential for nematode development, (1) nematode secreted effectors are becoming recognized as suppressors of plant immunity. (2)(-) (4) Recently we reported that the effector ubiquitin carboxyl extension protein (GrUBCEP12) from G. rostochiensis is processed into free ubiquitin and a 12-amino acid GrCEP12 peptide in planta. Transgenic potato lines overexpressing the derived GrCEP12 peptide showed increased susceptibility to G. rostochiensis and to an unrelated bacterial pathogen Streptomyces scabies, suggesting that GrCEP12 has a role in suppressing host basal defense or possibly pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) during the parasitic interaction. (3) To determine if GrCEP12 functions as a PTI suppressor we evaluated whether GrCEP12 suppresses flg22-induced PTI responses in Nicotiana benthamiana. Interestingly, we found that transient expression of GrCEP12 in N. benthamiana leaves suppressed reactive oxygen species (ROS) production and the induction of two PTI marker genes triggered by the bacterial PAMP flg22, providing direct evidence that GrCEP12 indeed has an activity in PTI suppression.

Management of ovarian cysts

DEFF Research Database (Denmark)

Knudsen, Ulla Breth; Tabor, Ann; Mosgaard, Berit Jul

2004-01-01

BACKGROUND: The treatment of an ovarian cyst relies on its nature, and accurate preoperative discrimination of benign and malignant cysts is therefore of crucial importance. This study was undertaken to review the literature concerning the preoperative diagnosis and treatment of ovarian cysts....... METHODS: Articles concerning ovarian cysts from a medline literature search during the period 1985-2003 were included in addition to articles found as references in the initial publications. RESULTS: Different methods for discriminating between benign and malignant ovarian cysts are discussed....... The diagnosis and the treatment are assessed in relation to age, menopausal status, pregnancy, and whether the cyst is presumed to be benign or malignant. In general, expectant management is the choice in premenopausal and pregnant women with non-suspicious cysts and normal levels of CA-125. In postmenopausal...

Comparative sequence analysis of the potato cyst nematode resistance locus H1 reveals a major lack of co-linearity between three haplotypes in potato (Solanum tuberosum ssp.).

Science.gov (United States)

Finkers-Tomczak, Anna; Bakker, Erin; de Boer, Jan; van der Vossen, Edwin; Achenbach, Ute; Golas, Tomasz; Suryaningrat, Suwardi; Smant, Geert; Bakker, Jaap; Goverse, Aska

2011-02-01

The H1 locus confers resistance to the potato cyst nematode Globodera rostochiensis pathotypes 1 and 4. It is positioned at the distal end of chromosome V of the diploid Solanum tuberosum genotype SH83-92-488 (SH) on an introgression segment derived from S. tuberosum ssp. andigena. Markers from a high-resolution genetic map of the H1 locus (Bakker et al. in Theor Appl Genet 109:146-152, 2004) were used to screen a BAC library to construct a physical map covering a 341-kb region of the resistant haplotype coming from SH. For comparison, physical maps were also generated of the two haplotypes from the diploid susceptible genotype RH89-039-16 (S. tuberosum ssp. tuberosum/S. phureja), spanning syntenic regions of 700 and 319 kb. Gene predictions on the genomic segments resulted in the identification of a large cluster consisting of variable numbers of the CC-NB-LRR type of R genes for each haplotype. Furthermore, the regions were interspersed with numerous transposable elements and genes coding for an extensin-like protein and an amino acid transporter. Comparative analysis revealed a major lack of gene order conservation in the sequences of the three closely related haplotypes. Our data provide insight in the evolutionary mechanisms shaping the H1 locus and will facilitate the map-based cloning of the H1 resistance gene.

Calcified adrenal cyst

Energy Technology Data Exchange (ETDEWEB)

Kim, Chung Kyu; Choi, Byung Sook [Yonsei University College of Medicine, Seoul (Korea, Republic of)

1970-10-15

Calcified hemorrhagic adrenal cysts are rather rare and unusual pathologic entity. Especially, the peripheral curvilinear calcification on roentgenogram is fairly characteristic picture of the cysts. Recently, we have experienced in Severance Hospital one of the classical cases of the benign calcified adrenal cyst in 35 year old white mail patient who has had vague abdominal pain and palpable mass in right abdomen. It has been reviewed several reports for adrenal cysts and hoped that this report may call additional attention of radiological diagnosis on this unusual disease.

Splenic epithelial cyst

International Nuclear Information System (INIS)

Yousuf, M.; Jalali, U.

2011-01-01

Cysts of spleen are rare entities. Congenital splenic cysts are even more uncommon comprising of only 10% of benign non-parasitic cysts. We report a case of 22 years old female who presented with history of 2 years abdominal pain and gradual distension. Ultrasound and computed tomography (CT) both were suggestive of splenic cyst. Laboratory tests show thrombocytopenia with platelets count of 97000 per cubic millimeter and anemia with hemoglobin 8.7 gram per deciliter. Serological tests were negative for parasitic infection. Splenectomy was done and the weight of the spleen was found to be 1.5 kilogram. Histopathological findings are consistent with splenic epithelial cyst. The aetiology, diagnostic modalities and treatment options are discussed in the case report. (author)

Transgenic soybeans and soybean protein analysis: an overview.

Science.gov (United States)

Natarajan, Savithiry; Luthria, Devanand; Bae, Hanhong; Lakshman, Dilip; Mitra, Amitava

2013-12-04

To meet the increasing global demand for soybeans for food and feed consumption, new high-yield varieties with improved quality traits are needed. To ensure the safety of the crop, it is important to determine the variation in seed proteins along with unintended changes that may occur in the crop as a result various stress stimuli, breeding, and genetic modification. Understanding the variation of seed proteins in the wild and cultivated soybean cultivars is useful for determining unintended protein expression in new varieties of soybeans. Proteomic technology is useful to analyze protein variation due to various stimuli. This short review discusses transgenic soybeans, different soybean proteins, and the approaches used for protein analysis. The characterization of soybean protein will be useful for researchers, nutrition professionals, and regulatory agencies dealing with soy-derived food products.

Tail gut cyst.

Science.gov (United States)

Rao, G Mallikarjuna; Haricharan, P; Ramanujacharyulu, S; Reddy, K Lakshmi

2002-01-01

The tail gut is a blind extension of the hindgut into the tail fold just distal to the cloacal membrane. Remnants of this structure may form tail gut cyst. We report a 14-year-old girl with tail gut cyst that presented as acute abdomen. The patient recovered after cyst excision.

Vaginal cysts

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/001509.htm Vaginal cysts To use the sharing features on this ... with air, fluid, pus, or other material. A vaginal cyst occurs on or under the lining of ...

Odontogenic cysts in three dogs: one odontogenic keratocyst and two dentigerous cysts.

Science.gov (United States)

Watanabe, Kazuhiro; Kadosawa, Tsuyoshi; Ishiguro, Taketo; Takagi, Satoshi; Ochiai, Kenji; Kimura, Takashi; Okumura, Masahiro; Fujinaga, Toru

2004-09-01

Odontogenic cysts, which showed cystic radiolucency in the jaw bone by radiographic examination and computed tomography, were enucleated by operation in 3 dogs. One dog had a odontogenic keratocyst in the incisive bone of the right maxilla and another 2 cases revealed dentigerous cysts in the mandible. These cyst walls were enucleated or transpired by semiconductor laser. Afterwards, osteogenesis was confirmed at the defective part of jaw bone by extirpation of the cyst in all cases, and no recurrence has been noted in any cases. Odontogenic cyst is a disease which should be treated by surgical extirpation or transpiration.

Odontogenic cysts in three dogs: One odontogenic keratocyst and two dentigerous cysts

International Nuclear Information System (INIS)

Watanabe, K.; Kadosawa, T.; Ishiguro, T.; Takagi, S.; Ochiai, K.; Kimura, T.; Okumura, M.; Fujinaga, T.

2004-01-01

Odontogenic cysts, which showed cystic radiolucency in the jaw bone by radiographic examination and computed tomography, were enucleated by operation in 3 dogs. One dog had a odontogenic keratocyst in the incisive bone of the right maxilla and another 2 cases revealed dentigerous cysts in the mandible. These cyst walls were enucleated or transpired by semiconductor laser. Afterwards, osteogenesis was confirmed at the defective pan of jaw bone by extirpation of the cyst in all cases, and no recurrence has been noted in any cases. Odontogenic cyst is a disease which should be treated by surgical extirpation or transpiration

Primary Peritoneal Hydatid Cyst Presenting as Ovarian Cyst Torsion: A Rare Case Report

OpenAIRE

Gandhiraman, Kavitha; Balakrishnan, Renukadevi; Ramamoorthy, Rathna; Rajeshwari, Raja

2015-01-01

Hydatid cyst disease is a zoonotic disease caused by Echinococcus granulosus, E.multilocularis or E.Vogli. The most common primary site is liver (75%) followed by lungs (5-15%) and other organs constitute 10-20%. Peritoneal hydatid cysts are very rare especially primary peritoneal hydatid. Secondary peritoneal hydatid cysts are relatively common, which usually occurs due to rupture of primary hepatic hydatid cyst. We present a rare case of large primary peritoneal hydatid cyst misdiagnosed as...

Biochemistry

Science.gov (United States)

Part of the framework for effective control or management of cyst nematodes depends upon the detailed understanding of their biology. This chapter summarizes fundamental knowledge and recent discoveries about the biochemistry of cyst nematodes, particularly areas related to lipids, carbohydrates and...

Evolution of GHF5 endoglucanase gene structure in plant-parasitic nematodes: no evidence for an early domain shuffling event

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Gheysen Godelieve

2008-11-01

Full Text Available Abstract Background Endo-1,4-beta-glucanases or cellulases from the glycosyl hydrolase family 5 (GHF5 have been found in numerous bacteria and fungi, and recently also in higher eukaryotes, particularly in plant-parasitic nematodes (PPN. The origin of these genes has been attributed to horizontal gene transfer from bacteria, although there still is a lot of uncertainty about the origin and structure of the ancestral GHF5 PPN endoglucanase. It is not clear whether this ancestral endoglucanase consisted of the whole gene cassette, containing a catalytic domain and a carbohydrate-binding module (CBM, type 2 in PPN and bacteria or only of the catalytic domain while the CBM2 was retrieved by domain shuffling later in evolution. Previous studies on the evolution of these genes have focused primarily on data of sedentary nematodes, while in this study, extra data from migratory nematodes were included. Results Two new endoglucanases from the migratory nematodes Pratylenchus coffeae and Ditylenchus africanus were included in this study. The latter one is the first gene isolated from a PPN of a different superfamily (Sphaerularioidea; all previously known nematode endoglucanases belong to the superfamily Tylenchoidea (order Rhabditida. Phylogenetic analyses were conducted with the PPN GHF5 endoglucanases and homologous endoglucanases from bacterial and other eukaryotic lineages such as beetles, fungi and plants. No statistical incongruence between the phylogenetic trees deduced from the catalytic domain and the CBM2 was found, which could suggest that both domains have evolved together. Furthermore, based on gene structure data, we inferred a model for the evolution of the GHF5 endoglucanase gene structure in plant-parasitic nematodes. Our data confirm a close relationship between Pratylenchus spp. and the root knot nematodes, while some Radopholus similis endoglucanases are more similar to cyst nematode genes. Conclusion We conclude that the ancestral

Evolution of GHF5 endoglucanase gene structure in plant-parasitic nematodes: no evidence for an early domain shuffling event.

Science.gov (United States)

Kyndt, Tina; Haegeman, Annelies; Gheysen, Godelieve

2008-11-03

Endo-1,4-beta-glucanases or cellulases from the glycosyl hydrolase family 5 (GHF5) have been found in numerous bacteria and fungi, and recently also in higher eukaryotes, particularly in plant-parasitic nematodes (PPN). The origin of these genes has been attributed to horizontal gene transfer from bacteria, although there still is a lot of uncertainty about the origin and structure of the ancestral GHF5 PPN endoglucanase. It is not clear whether this ancestral endoglucanase consisted of the whole gene cassette, containing a catalytic domain and a carbohydrate-binding module (CBM, type 2 in PPN and bacteria) or only of the catalytic domain while the CBM2 was retrieved by domain shuffling later in evolution. Previous studies on the evolution of these genes have focused primarily on data of sedentary nematodes, while in this study, extra data from migratory nematodes were included. Two new endoglucanases from the migratory nematodes Pratylenchus coffeae and Ditylenchus africanus were included in this study. The latter one is the first gene isolated from a PPN of a different superfamily (Sphaerularioidea); all previously known nematode endoglucanases belong to the superfamily Tylenchoidea (order Rhabditida). Phylogenetic analyses were conducted with the PPN GHF5 endoglucanases and homologous endoglucanases from bacterial and other eukaryotic lineages such as beetles, fungi and plants. No statistical incongruence between the phylogenetic trees deduced from the catalytic domain and the CBM2 was found, which could suggest that both domains have evolved together. Furthermore, based on gene structure data, we inferred a model for the evolution of the GHF5 endoglucanase gene structure in plant-parasitic nematodes. Our data confirm a close relationship between Pratylenchus spp. and the root knot nematodes, while some Radopholus similis endoglucanases are more similar to cyst nematode genes. We conclude that the ancestral PPN GHF5 endoglucanase gene most probably consisted of

Anatomical Alterations in Plant Tissues Induced by Plant-Parasitic Nematodes

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Juan E. Palomares-Rius

2017-11-01

Full Text Available Plant-parasitic nematodes (PPNs interact with plants in different ways, for example, through subtle feeding behavior, migrating destructively through infected tissues, or acting as virus-vectors for nepoviruses. They are all obligate biotrophic parasites as they derive their nutrients from living cells which they modify using pharyngeal gland secretions prior to food ingestion. Some of them can also shield themselves against plant defenses to sustain a relatively long lasting interaction while feeding. This paper is centered on cell types or organs that are newly induced in plants during PPN parasitism, including recent approaches to their study based on molecular biology combined with cell biology-histopathology. This issue has already been reviewed extensively for major PPNs (i.e., root-knot or cyst nematodes, but not for other genera (viz. Nacobbus aberrans, Rotylenchulus spp.. PPNs have evolved with plants and this co-evolution process has allowed the induction of new types of plant cells necessary for their parasitism. There are four basic types of feeding cells: (i non-hypertrophied nurse cells; (ii single giant cells; (iii syncytia; and (iv coenocytes. Variations in the structure of these cells within each group are also present between some genera depending on the nematode species viz. Meloidogyne or Rotylenchulus. This variability of feeding sites may be related in some way to PPN life style (migratory ectoparasites, sedentary ectoparasites, migratory ecto-endoparasites, migratory endoparasites, or sedentary endoparasites. Apart from their co-evolution with plants, the response of plant cells and roots are closely related to feeding behavior, the anatomy of the nematode (mainly stylet size, which could reach different types of cells in the plant, and the secretory fluids produced in the pharyngeal glands. These secretory fluids are injected through the stylet into perforated cells where they modify plant cytoplasm prior to food removal

In Vivo Production of Entomopathogenic Nematodes.

Science.gov (United States)

Shapiro-Ilan, David I; Morales-Ramos, Juan A; Rojas, M Guadalupe

2016-01-01

In nature, entomopathogenic nematodes in the genera Heterorhabditis and Steinernema are obligate parasites of insects. The nematodes are used widely as biopesticides for suppression of insect pests. More than a dozen entomopathogenic nematode species have been commercialized for use in biological control. Most nematodes intended for commercial application are produced in artificial media via solid or liquid fermentation. However, for laboratory research and small greenhouse or field trials, in vivo production of entomopathogenic nematodes is the common method of propagation. Additionally, small companies continue to produce nematodes using in vivo methods for application in niche markets. Advances in mechanization and alternative production routes (e.g., production geared toward application of nematodes in infected host cadavers) can improve efficiency and economy of scale. The objective of this chapter is to describe basic and advanced procedures for in vivo production of entomopathogenic nematodes.

Nonsurgical root canal therapy of large cyst-like inflammatory periapical lesions and inflammatory apical cysts.

Science.gov (United States)

Lin, Louis M; Ricucci, Domenico; Lin, Jarshen; Rosenberg, Paul A

2009-05-01

It is a general belief that large cyst-like periapical lesions and apical true cysts caused by root canal infection are less likely to heal after nonsurgical root canal therapy. Nevertheless, there is no direct evidence to support this assumption. A large cyst-like periapical lesion or an apical true cyst is formed within an area of apical periodontitis and cannot form by itself. Therefore, both large cyst-like periapical lesions and apical true cysts are of inflammatory and not of neoplastic origin. Apical periodontitis lesions, regardless of whether they are granulomas, abscesses, or cysts, fail to heal after nonsurgical root canal therapy for the same reason, intraradicular and/or extraradicular infection. If the microbial etiology of large cyst-like periapical lesions and inflammatory apical true cysts in the root canal is removed by nonsurgical root canal therapy, the lesions might regress by the mechanism of apoptosis in a manner similar to the resolution of inflammatory apical pocket cysts. To achieve satisfactory periapical wound healing, surgical removal of an apical true cyst must include elimination of root canal infection.

Keratinizing dentigerous cyst

Science.gov (United States)

Sivasankar, Vaishnavi; Ranganathan, Kannan; Praveen, B

2014-01-01

Keratinizing dentigerous cyst is a rare entity. This article reports a case of keratinizing dentigerous cyst associated with an impacted mandibular canine. Clinical and radiological features, cone-beam computed tomography findings and histological features of the case are reported along with a discussion on keratinizing odontogenic cysts and the need for follow-up. PMID:24808713

Keratinizing dentigerous cyst

Directory of Open Access Journals (Sweden)

Vaishnavi Sivasankar

2014-01-01

Full Text Available Keratinizing dentigerous cyst is a rare entity. This article reports a case of keratinizing dentigerous cyst associated with an impacted mandibular canine. Clinical and radiological features, cone-beam computed tomography findings and histological features of the case are reported along with a discussion on keratinizing odontogenic cysts and the need for follow-up.

Submental epidermoid cysts in children.

Science.gov (United States)

Zielinski, Rafal; Zakrzewska, Anna

2015-01-01

Epidermoid cysts are lesions, which form as a result of implantation of the epidermis in the layers of the dermis or the mucous membrane. The lesions are rare in adults with 7% occurring in the head and neck area and most often located in the submental region. In children population submental epidermoid cysts are extremely rare. The differential diagnosis of the lesions is necessary as it affects the choice of treatment methods. Among the pathological conditions occurring in that region, salivary retention cyst (ranula), thyroglossal duct cyst, vascular lymphatic malformation (cystic hygroma), median neck cyst, lymphadenopathy, thyroid gland tumor, laryngeal cyst, epidermoid and dermoid cysts, submental abscess, sialolithiasis and salivary gland inflammation should be considered. The authors of the present report demonstrate two cases of submental epidermoid cysts in children. Differential diagnosis in case of suspected submental epidermoid cyst in a child with proposed clinical practice and literature review is provided.

Olfactory circuits and behaviors of nematodes.

Science.gov (United States)

Rengarajan, Sophie; Hallem, Elissa A

2016-12-01

Over one billion people worldwide are infected with parasitic nematodes. Many parasitic nematodes actively search for hosts to infect using volatile chemical cues, so understanding the olfactory signals that drive host seeking may elucidate new pathways for preventing infections. The free-living nematode Caenorhabditis elegans is a powerful model for parasitic nematodes: because sensory neuroanatomy is conserved across nematode species, an understanding of the microcircuits that mediate olfaction in C. elegans may inform studies of olfaction in parasitic nematodes. Here we review circuit mechanisms that allow C. elegans to respond to odorants, gases, and pheromones. We also highlight work on the olfactory behaviors of parasitic nematodes that lays the groundwork for future studies of their olfactory microcircuits. Copyright © 2016 Elsevier Ltd. All rights reserved.

The expression of R genes in genetic and induced resistance to potato cyst nematode Globodera rostochiensis (Wollenweber, 1923) Behrens, 1975.

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Lavrova, V V; Matveeva, E M; Zinovieva, S V

2015-01-01

The characteristics of expression of two genes, H1 and Gro1-4, which determine the resistance to the sedentary parasitic nematode Globodera rostochiensis (Wollenweber, 1923) Behrens, 1975, in the resistant (Krepysh) and susceptible (Nevskii) potato cultivars was studied under a short-term exposure to low temperatures. Such treatment of susceptible plants at the early stages of ontogeny led to the activation of expression of H1 and Gro1-4 genes in roots and the H1 gene in leaves. The transcriptional activity of R genes was detected not only in roots but also in leaves (i.e., in tissue remote from the site of direct injury by the nematode) in the case of both genetic and induced resistance, indicating the development of a systemic defense response of plants to infection.

Nutritional value of raw soybeans, extruded soybeans, roasted soybeans and tallow as fat sources in early lactating dairy cows.

Science.gov (United States)

Amanlou, H; Maheri-Sis, N; Bassiri, S; Mirza-Aghazadeh, A; Salamatdust, R; Moosavi, A; Karimi, V

2012-01-01

Thirty multiparous Holstein cows (29.8 ± 4.01days in milk; 671.6 ± 31.47 kg of body weight) were used in a completely randomized design to compare nutritional value of four fat sources including tallow, raw soybeans, extruded soybeans and roasted soybeans for 8 weeks. Experimental diets were a control containing 27.4 % alfalfa silage, 22.5% corn silage, and 50.1% concentrate, and four diets with either tallow, raw soybean, extruded soybean, or roasted soybean added to provide 1.93% supplemental fat. Dry matter and NEL intakes were similar among treatments, while cows fed fat diets had significantly (Pfat. Supplemental fat, whether tallow or full fat soybeans increased milk production (1.89-2.45 kg/d; PMilk fat yield and percentage of cows fed fat-supplemented diets were significantly (Pfat-supplemented diets, roasted soybean caused highest milk fat yield and extruded soybean caused lowest milk fat yield. There was no significant effect of supplemental fat on the milk protein and lactose content and yield. Feed efficiency of fat-supplemented diets was significantly (Pfat sources on production response of cows, fat originating from heat-treated soybean help to minimize imported RUP (rumen undegradable protein) sources level as fish meal in comparison with tallow and raw soybean oil. In the Current study, there was no statistical significance among nutritional values of oil from extruded soybeans and roasted soybeans.

Primary Posterior Mediastinum Hydatid Cyst

International Nuclear Information System (INIS)

Ahmed, M.; Eid, A. F.; Sheikh, M. Y.; Yiannakou, N.

2014-01-01

Primary posterior mediastinal hydatid cyst is a serious health problem for the Mediterranean countries. We diagnosed a case of a 46-year-old female with a primary posterior mediastinum hydatid cyst on CT and MRI. It was provisionally identified as either a hydatid cyst or bronchogenic cyst or neuroenteric cyst. CT guided aspiration with 18 gauge needle confirmed as hydatid sand. This is very rare in this population but it should be kept in mind when one is looking at any cyst in the posterior mediastinum. (author)

Nematode parasites of animals are more prone to develop xenobiotic resistance than nematode parasites of plants

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Silvestre A.

2004-06-01

Full Text Available In this paper, we concentrate on a comparison of plant and animal-parasitic nematodes, to gain insight into the factors that influence the acquisition of the drug resistance by nematodes. Comparing nematode parasite of domestic animals and cultivated plants, it appears that drug resistance threatens only domestic animal production. Does the paucity of report on nematicide field resistance reflect reality or, is nematicide resistance bypassed by other management practices, specific to cultivated plants (i.e. agricultural control ? First, it seems that selection pressure by treatments in plants is not as efficient as selection pressure in ruminants. Agronomic practices (i.e. sanitation, early planting, usage of nematodes resistant cultivar and crop rotation are frequently used to control parasitic-plant nematodes. Although the efficiency of such measures is generally moderate to high, integrated approaches are developing successfully in parasitic-plant nematode models. Secondly, the majority of anthelmintic resistance cases recorded in animal-parasitic nematodes concern drug families that are not used in plant-parasitic nematodes control (i.e. benzimidazoles, avermectines and levamisole. Thirdly, particular life traits of parasitic-plant nematodes (low to moderate fecundity and reproductive strategy are expected to reduce probability of appearance and transmission of drug resistance genes. It has been demonstrated that, for a large number of nematodes such as Meloidogyne spp., the mode of reproduction by mitotic parthenogenesis reduced genetic diversity of populations which may prevent a rapid drug resistance development. In conclusion, anthelmintic resistance develops in nematode parasite of animals as a consequence of an efficient selection pressure. Early detection of anthelmintic resistance is then crucial : it is not possible to avoid it, but only to delay its development in farm animal industry.

Pathogenicity and host range of Heterodera arenaria in coastal foredunes

NARCIS (Netherlands)

Stoel, C.D.; Putten, van der W.H.

2006-01-01

In coastal foredunes, the cyst nematode Heterodera arenaria has been supposed to play a role in degeneration of the pioneer grass Ammophila arenaria (marram grass). However, recent field surveys and field inoculation experiments suggested that the abundance of this cyst nematode is controlled by the

Draft transcriptome of Globodera ellingtonae

Science.gov (United States)

The recently described cyst nematode species, Globodera ellingtonae, is a phylogenetic intermediary between the potato cyst nematodes (PCN), G. rotochiensis and G. pallida, and as such provides a new avenue for understanding the evolution and biology of PCN. Given that assembled genomes and transcri...

A new chorismate mutase gene identified from Globodera ellingtonae and its utility as a molecular diagnostic marker

Science.gov (United States)

Globodera ellingtonae, a new cyst nematode species recently detected in Oregon and confirmed of reproduction on potato, shares key morphological features with the two species of potato cyst nematode (PCN; G. rostochiensis and G. pallida) of quarantine concern. Currently no methods are available for ...

Population-specific gene expression in the plant pathogenic nematode Heterodera glycines exists prior to infection and during the onset of a resistant or susceptible reaction in the roots of the Glycine max genotype Peking

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Alkharouf Nadim W

2009-03-01

Full Text Available Abstract Background A single Glycine max (soybean genotype (Peking reacts differently to two different populations of Heterodera glycines (soybean cyst nematode within the first twelve hours of infection during resistant (R and susceptible (S reactions. This suggested that H. glycines has population-specific gene expression signatures. A microarray analysis of 7539 probe sets representing 7431 transcripts on the Affymetrix® soybean GeneChip® were used to identify population-specific gene expression signatures in pre-infective second stage larva (pi-L2 prior to their infection of Peking. Other analyses focused on the infective L2 at 12hours post infection (i-L212h, and the infective sedentary stages at 3days post infection (i-L23d and 8days post infection (i-L2/L38d. Results Differential expression and false discovery rate (FDR analyses comparing populations of pi-L2 (i.e., incompatible population, NL1-RHg to compatible population, TN8 identified 71 genes that were induced in NL1-RHg as compared to TN8. These genes included putative gland protein G23G12, putative esophageal gland protein Hgg-20 and arginine kinase. The comparative analysis of pi-L2 identified 44 genes that were suppressed in NL1-RHg as compared to TN8. These genes included a different Hgg-20 gene, an EXPB1 protein and a cuticular collagen. By 12 h, there were 7 induced genes and 0 suppressed genes in NL1-RHg. By 3d, there were 9 induced and 10 suppressed genes in NL1-RHg. Substantial changes in gene expression became evident subsequently. At 8d there were 13 induced genes in NL1-RHg. This included putative gland protein G20E03, ubiquitin extension protein, putative gland protein G30C02 and β-1,4 endoglucanase. However, 1668 genes were found to be suppressed in NL1-RHg. These genes included steroid alpha reductase, serine proteinase and a collagen protein. Conclusion These analyses identify a genetic expression signature for these two populations both prior to and subsequently

The evolutionary position of nematodes

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Gojobori Takashi

2002-04-01

Full Text Available Abstract Background The complete genomes of three animals have been sequenced by global research efforts: a nematode worm (Caenorhabditis elegans, an insect (Drosophila melanogaster, and a vertebrate (Homo sapiens. Remarkably, their relationships have yet to be clarified. The confusion concerns the enigmatic position of nematodes. Traditionally, nematodes have occupied a basal position, in part because they lack a true body cavity. However, the leading hypothesis now joins nematodes with arthropods in a molting clade, Ecdysozoa, based on data from several genes. Results We tested the Ecdysozoa hypothesis with analyses of more than 100 nuclear protein alignments, under conditions that would expose biases, and found that it was not supported. Instead, we found significant support for the traditional hypothesis, Coelomata. Our result is robust to different rates of sequence change among genes and lineages, different numbers of taxa, and different species of nematodes. Conclusion We conclude that insects (arthropods are genetically and evolutionarily closer to humans than to nematode worms.

Interactions between nematophagous fungi and consequences for their potential as biological agents for the control of potato cyst nematodes.

Science.gov (United States)

Jacobs, Helen; Gray, Simon N; Crump, David H

2003-01-01

The efficacies of three nematophagous fungi, Paecilomyces lilacinus, Plectosphaerella cucumerina and Pochonia chlamydosporia, for controlling potato cyst nematodes (PCN) as part of an Integrated Pest Management (IPM) regime were studied. The compatibility of the nematophagous fungi with commonly used chemical pesticides and their ability to compete with the soil fungi Rhizoctonia solani, Chaetomium globosum, Fusarium oxysporum, Penicillium bilaii and Trichoderma harzianum were tested in vitro. Paecilomyces lilacinus was the most successful competitor when the ability to grow and inhibit growth of an opposing colony at both 10 and 20 degrees C was considered. P. lilacinus also showed potential for control of the soil-borne fungal pathogen R. solani, releasing a diffusable substance in vitro which inhibited its growth and caused morphological abnormalities in its hyphae. Pochonia chlamydosporia was least susceptible to growth inhibition by other fungi at 20 degrees in vitro, but the isolate tested did not grow at 10 degrees. Plectosphaerella cucumerina was a poor saprophytic competitor. Radial growth of Paecilomyces lilacinus and Plectosphaerella cucumerina was slowed, but not prevented, when grown on potato dextrose agar incorporating the fungicides fenpiclonil and tolclofos-methyl, and was not inhibited by the addition of pencycuron or the nematicide oxamyl. Radial growth of Pochonia chlamydosporia was partially inhibited by all the chemical pesticides tested. The efficacy of Paecilomyces lilacinus as a control agent for R. solani was further investigated in situ. Treatment with P. lilacinus significantly reduced the symptoms of Rhizoctonia disease on potato stems in a pot trial. The effectiveness of P. lilacinus and P. cucumerina against PCN was also tested in situ. Three application methods were compared; incorporating the fungi into alginate pellets, Terra-Green inoculated with the fungi and applying conidia directly to the tubers. Both formulations containing P

Congenital Hepatic Cyst

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Aldo Recinos

2017-04-01

Full Text Available Congenital hepatic cyst is a rare and nonsymptomatic condition in infants and children. Its incidence is 2.5% in the postnatal life with a much lower incidence in the prenatal period. Incidental finding on antenatal imaging is the most common presentation. We present a case of a newborn in whom fetal ultrasound detected a cyst within the fetal liver. Postnatal imaging revealed a liver cyst in the right lobe of the liver, with no other intrahepatic structure affected. Liver function tests were abnormal, but the patient was asymptomatic. Posterior follow-up imaging showed a minor decrease in size. Management of congenital hepatic cyst is usually conservative, done with periodic ultrasound monitoring. However, surgical treatment is the mainstay of treatment when hydrops, progressive enlargement, hemorrhage, torsion, or compression of adjacent structures occurs. Malignant transformation can occur, but it is extremely rare. Partial or total removal of the cyst is the preferred treatment in neonates with a large lesion.

Epidemiological studies of nematodes in fishes

International Nuclear Information System (INIS)

Qamar, M.F.; Butt, K.; Qureshi, N.A.

2014-01-01

Three hundred fresh water fishes of six species were collected from six different fish farms of Lahore for the prevalence of nematodes. Out of 300 fishes examined, 12 were found to be infected with the helminthes, majority of them were isolated from the stomach and intestines. The following two species of nematodes were recorded; Capillaria spp. and Eustrongylides spp. The overall prevalence of intestinal nematodes was recorded as 4%(12/300). The prevalence of nematodes was recorded on monthly basis which ranged from 0-8%. The highest prevalence of nematodes was 8% (4/50) during March, while the lowest prevalence was noted in June 0%.Singharee (Sperata sawari) showed the maximum infestation of nematodes of 8% (4/50), whereas in Silver Carp (Hypopthaimichthys molitrix) minimum prevalence of nematode (0%) was noted. The prevalence of different nematode in a particular fish specie was also recorded, and it was stated that overall prevalence of capillaria spp. was 6% in Rahu (Labeo rohita) and Saul (Channa marullius). Similarly overall infestation of Eustrongylides sp. was recorded as 4% in Singharee (Sperata sawari) and Silver carp (Hypopthaimichthys molitrix). The nematode intensity might be linked with the genetic makeup, intestinal vigor, and other managemental and environmental factors. (author)

A new oomycete species parasitic in nematodes, Chlamydomyzium dictyuchoides sp. nov.: developmental biology and phylogenetic studies.

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Beakes, Gordon W; Glockling, Sally L; James, Timothy Y

2014-07-01

The genus Chlamydomyzium is a little studied holocarpic oomycete parasite of nematodes of uncertain phylogenetic and taxonomic position. A new holocarpic species, Chlamydomyzium dictyuchoides, is described which has usually refractile cytoplasm and a dictyuchoid pattern of spore release. This new species infects bacteriotrophic rhabditid nematodes and was isolated from diverse geographical locations. Infection was initiated by zoospore encystment on the host surface and direct penetration of the cuticle. A sparsely branched, constricted, refractile thallus was formed which eventually occupied almost the entire host body cavity, often accompanied by complete dissolution of the host cuticle. Walled primary cysts formed throughout the thallus and each cyst released a single zoospore via an individual exit papillum, leaving a characteristic dictyuchoid wall net behind. At later stages of infection some thalli formed thick-walled stellate resting spores in uniseriate rows. Resting spore formation appeared to be parthenogenetic and was not accompanied by the formation of antheridial compartments. These spores had ooplast-like vacuoles and thick multi-layered walls, both of which suggest they were oospores. The maximum likelihood tree of sequences of the small ribosomal subunit (SSU) gene placed this new isolate in a clade before the main saprolegnialean and peronosporalean lines diverge. A second undescribed Chlamydomyzium sp., which has direct spore release forms a paraphyletic clade, close to C. dictyuchoides and Sapromyces. The fine structure of other documented Chlamydomyzium species was compared, including an undescribed (but sequenced) isolate, SL02, from Japan, Chlamydomyzium anomalum and Chlamydomyzium oviparasiticum. Chlamydomyzium as currently constituted is a paraphyletic genus that is part of a group of phylogenetically problematic early diverging clades that lie close to both the Leptomitales and Rhipidiales. Crown Copyright © 2014. Published by Elsevier

Imaging of nasopharyngeal cysts and bursae

International Nuclear Information System (INIS)

Ben Salem, D.; Ricolfi, Frederic; Duvillard, Christian; Ballester, Michel; Assous, Dorothee; Krause, Denis

2006-01-01

Cysts and bursae of the nasopharynx are uncommon and seldom symptomatic when compared with malignant tumors of this region. However, it is noteworthy that in the presence of symptoms, a good knowledge of their radiological appearance is useful to establish the correct diagnosis. Cysts of Rathke's pouch, pharyngeal bursa of Luschka, Tornwaldt's cysts, retentional cysts of the seromucinous glands, oncocytic cysts, intra-adenoid cysts, branchial cysts, prevertebral or retropharyngeal abscess and pseudocysts of the nasopharynx will be discussed in this paper. (orig.)

Histologic and immunohistochemical characteristics of cutaneous cysts in Goltz-Gorlin syndrome: clues for differentiation of nonsyndromic cysts.

Science.gov (United States)

Tirado, Mariantonieta; Ständer, Sonja; Metze, Dieter

2014-11-01

Goltz-Gorlin syndrome presents with multiple basal cell carcinomas, odontogenic keratocysts, and cutaneous cysts, among other manifestations. The cutaneous cysts have been described as both epidermoid cysts and keratocysts but were not further characterized. Light microscopic examinations were made on 23 cutaneous cysts in 4 patients associated with Goltz-Gorlin syndrome located on extremities, face, trunk, palms, and soles and compared with nonsyndromic vellus hair cysts, steatocystomas, and hybrid cysts. Twenty-one of the syndromic cysts revealed alternating infundibular-like and steatocystoma-like squamous epitheliums in varying proportions. The cysts were lined by both smooth and corrugated squamous epithelium. The horny layer was composed by alternating areas of thin, lamellate, and compact eosinophilic keratin. Only 2 cases showed an exclusive steatocystoma-like type of epithelium very similar to odontogenic keratocysts. Sebaceous glands and follicular structures were absent. There were no differences between palmar and plantar cysts and other anatomic locations. The ultrastructural findings in syndromatic cysts confirmed variable expression of keratohyalin granules. Only 3 of 6 cases of nonsyndromic hybrid cysts showed overlapping features with syndromic cysts. Immunohistochemical profiling of keratin, involucrin, filaggrin, loricrin, and BCL-2 expression in syndromatic cysts showed exclusive positivity of K19 and continuous staining for BCL-2. In summary, 2 types of cutaneous cysts are characteristic of Goltz-Gorlin, irrelevant of their anatomic location, namely steatocystoma-like and more frequently hybrid-like. The diagnosis of syndromic hybrid-like cysts should be considered whenever infundibular and steatocystoma differentiation alternate and overlap. Altogether, these findings in epithelial cysts may raise the suspicion of Goltz-Gorlin as an underlying cause.

Imaging of nasopharyngeal cysts and bursae

Energy Technology Data Exchange (ETDEWEB)

Ben Salem, D.; Ricolfi, Frederic [CHU DIJON, Service de Neuroradiologie et de Radiologie des Urgences, Dijon, Cedex (France); Duvillard, Christian; Ballester, Michel [CHU DIJON, Service d' ORL, Dijon, Cedex (France); Assous, Dorothee [CHU DIJON, Service d' Anatomie et de Cytologie Pathologiques Faculte de Medecine, Dijon, Cedex (France); Krause, Denis [CHU DIJON, Service d' Imagerie Diagnostique et Interventionnelle, Dijon, Cedex (France)

2006-10-15

Cysts and bursae of the nasopharynx are uncommon and seldom symptomatic when compared with malignant tumors of this region. However, it is noteworthy that in the presence of symptoms, a good knowledge of their radiological appearance is useful to establish the correct diagnosis. Cysts of Rathke's pouch, pharyngeal bursa of Luschka, Tornwaldt's cysts, retentional cysts of the seromucinous glands, oncocytic cysts, intra-adenoid cysts, branchial cysts, prevertebral or retropharyngeal abscess and pseudocysts of the nasopharynx will be discussed in this paper. (orig.)

Nematode communities in contaminated river sediments

International Nuclear Information System (INIS)

Heininger, Peter; Hoess, Sebastian; Claus, Evelyn; Pelzer, Juergen; Traunspurger, Walter

2007-01-01

Nematode communities of eight sites from three river catchments were investigated in terms of the genera composition, feeding types, and life-history strategists. The sampling sites showed a gradient of anthropogenic contamination with heavy metals and organic pollutants being important factors in differentiating the sites. Nematode community structure was related to sediment pollution and the hydro-morphological structure of the sampling sites. Heavily contaminated sites were characterized by communities with high relative abundances of omnivorous and predacious nematodes (Tobrilus, c-p 3; Mononchus, c-p 4), while sites with low to medium contamination were dominated by bacterivorous nematodes (Monhystera, Daptonema; c-p 2) or suction feeders (Dorylaimus, c-p 4). The relatively high Maturity Index values in the heavily polluted sites were surprising. Nematodes turned out to be a suitable organism group for monitoring sediment quality, with generic composition being the most accurate indicator for assessing differences in nematode community structure. - Nematode community structure of river sediments is related to pollution and site structure

Nematode communities in contaminated river sediments

Energy Technology Data Exchange (ETDEWEB)

Heininger, Peter [Federal Institute of Hydrology (BfG), Am Mainzer Tor 1, 56068 Koblenz (Germany); Hoess, Sebastian [Ecossa - Ecological Sediment and Soil Assessment, Thierschstr. 43, 80538 Munich (Germany); Claus, Evelyn [Federal Institute of Hydrology (BfG), Am Mainzer Tor 1, 56068 Koblenz (Germany); Pelzer, Juergen [Federal Institute of Hydrology (BfG), Am Mainzer Tor 1, 56068 Koblenz (Germany); Traunspurger, Walter [University of Bielefeld, Department of Animal Ecology, Morgenbreede 45, 33615 Bielefeld (Germany)]. E-mail: traunspurger@uni-bielefeld.de

2007-03-15

Nematode communities of eight sites from three river catchments were investigated in terms of the genera composition, feeding types, and life-history strategists. The sampling sites showed a gradient of anthropogenic contamination with heavy metals and organic pollutants being important factors in differentiating the sites. Nematode community structure was related to sediment pollution and the hydro-morphological structure of the sampling sites. Heavily contaminated sites were characterized by communities with high relative abundances of omnivorous and predacious nematodes (Tobrilus, c-p 3; Mononchus, c-p 4), while sites with low to medium contamination were dominated by bacterivorous nematodes (Monhystera, Daptonema; c-p 2) or suction feeders (Dorylaimus, c-p 4). The relatively high Maturity Index values in the heavily polluted sites were surprising. Nematodes turned out to be a suitable organism group for monitoring sediment quality, with generic composition being the most accurate indicator for assessing differences in nematode community structure. - Nematode community structure of river sediments is related to pollution and site structure.

Isolated Cardiac Hydatid Cyst

International Nuclear Information System (INIS)

Shakil, U.; Rehman, A. U.; Shahid, R.

2015-01-01

Hydatid cyst disease is common in our part of the world. Cardiac hydatid cyst is its rare manifestation. We report this case of 48-year male having isolated cardiac hydatid cyst, incidentally found on computed tomography. This patient presented in medical OPD of Combined Military Hospital, Lahore with one month history of mild retrosternal discomfort. His general physical and systemic examinations as well as ECG were unremarkable. Chest X-ray showed an enlarged cardiac shadow with mildly irregular left heart border. Contrast enhanced CT scan of the chest showed a large well defined multiloculated non-enhancing cystic lesion with multiple daughter cysts involving wall of left ventricle and overlying pericardium. Serology for echinococcus confirmed the diagnosis of hydatid cyst. Patient was offered the surgical treatment but he opted for medical treatment only. Albendezol was prescribed. His follow-up echocardiography after one month showed no significant decrease in size of the cyst. (author)

Acetic acid sclerotheraphy of renal cysts

International Nuclear Information System (INIS)

Hong, Hoon Pyo; Oh, Joo Hyeong; Yoon, Yup; Kong, Keun Young; Kim, Eui Jong; Goo, Jang Sung

1998-01-01

Sclerotherapy for renal cysts was performed, using 50% acetic acid as new sclerosing agent. We report the methods and results of this procedure. Fifteen patients underwent sclerotherapy for renal cyst, using 50% acetic acid. Because four patients were lost to follow-up, only 11 of the 15 were included in this study. The renal cysts, including one infected case, were diagnosed by ultrasonograpy (n=3D10) ormagnetic resonance imaging (n=3D1). The patient group consisted of four men and seven women(mean age, 59 years; range, 23-77). At first, the cyst was completely aspirated, and 25 volume% of aspirated volume was replaced with 50% sterile acetic acid through the drainage catheter. During the follwing 20 minutes, the patient changed position, and the acetic acid was then removed from the cyst. Finally, the drainage catheter was removed, after cleaning the cyst with saline. After treatment of infection by antibiotics and catheter drainage for 7 days, sclerotherapy in the infected case followed the same procedure. In order to observe changes in the size of renal cysts and recurrence, all patients were followed up by ultrasound between 2 and 8 months. We defined response to therapy as follows:complete regression as under 5 volume%, partial regression as 5-50 volume% and no response as more than 50 volume% of initial cyst volume. No clinically significant complication occured during the procedures or follow-up periods. All cysts regressed completely during follow-up of 8 months. Complete regression occurred as follows: two cysts at 2 months, seven cysts at 4 months, two cysts at 6 months. Two cysts showed residues at the last follow-up, at 4 and 6 months, respectively. The volume of residual cysts decreased to under 5 volume% of initial volume, however. Completely regressed cysts did not recurr during follow-up. Acetic acid sclerotherapy for renal cysts showed good results, regardless of the dilution of sclerosing agent with residual cyst fluid, and no significant

RNAi effector diversity in nematodes.

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Johnathan J Dalzell

2011-06-01

Full Text Available While RNA interference (RNAi has been deployed to facilitate gene function studies in diverse helminths, parasitic nematodes appear variably susceptible. To test if this is due to inter-species differences in RNAi effector complements, we performed a primary sequence similarity survey for orthologs of 77 Caenorhabditis elegans RNAi pathway proteins in 13 nematode species for which genomic or transcriptomic datasets were available, with all outputs subjected to domain-structure verification. Our dataset spanned transcriptomes of Ancylostoma caninum and Oesophagostomum dentatum, and genomes of Trichinella spiralis, Ascaris suum, Brugia malayi, Haemonchus contortus, Meloidogyne hapla, Meloidogyne incognita and Pristionchus pacificus, as well as the Caenorhabditis species C. brenneri, C. briggsae, C. japonica and C. remanei, and revealed that: (i Most of the C. elegans proteins responsible for uptake and spread of exogenously applied double stranded (dsRNA are absent from parasitic species, including RNAi-competent plant-nematodes; (ii The Argonautes (AGOs responsible for gene expression regulation in C. elegans are broadly conserved, unlike those recruited during the induction of RNAi by exogenous dsRNA; (iii Secondary Argonautes (SAGOs are poorly conserved, and the nuclear AGO NRDE-3 was not identified in any parasite; (iv All five Caenorhabditis spp. possess an expanded RNAi effector repertoire relative to the parasitic nematodes, consistent with the propensity for gene loss in nematode parasites; (v In spite of the quantitative differences in RNAi effector complements across nematode species, all displayed qualitatively similar coverage of functional protein groups. In summary, we could not identify RNAi effector deficiencies that associate with reduced susceptibility in parasitic nematodes. Indeed, similarities in the RNAi effector complements of RNAi refractory and competent nematode parasites support the broad applicability of this research

RNA-Seq reveals the molecular mechanism of trapping and killing of root-knot nematodes by nematode-trapping fungi.

Science.gov (United States)

Pandit, Ramesh; Patel, Reena; Patel, Namrata; Bhatt, Vaibhav; Joshi, Chaitanya; Singh, Pawan Kumar; Kunjadia, Anju

2017-04-01

Nematode-trapping fungi are well known for their inherent potential to trap and kill nematodes using specialized trapping devices. However, the molecular mechanisms underlying the trapping and subsequent processes are still unclear. Therefore, in this study, we examined differential genes expression in two nematode-trapping fungi after baiting with nematode extracts. In Arthrobotrys conoides, 809 transcripts associated with diverse functions such as signal transduction, morphogenesis, stress response and peroxisomal proteins, proteases, chitinases and genes involved in the host-pathogen interaction showed differential expression with fold change (>±1.5 fold) in the presence of nematode extract with FDR (p-value nematode-trapping fungi for its host. The findings illustrate the molecular mechanism of fungal parasitism in A. conoides which may be helpful in developing a potential biocontrol agent against parasitic nematodes.

Nutritional value of raw soybeans, extruded soybeans, roasted soybeans and tallow as fat sources in early lactating dairy cows

Directory of Open Access Journals (Sweden)

A. Moosavi

2012-09-01

Full Text Available Thirty multiparous Holstein cows (29.8 ± 4.01days in milk; 671.6 ± 31.47 kg of body weight were used in a completely randomized design to compare nutritional value of four fat sources including tallow, raw soybeans, extruded soybeans and roasted soybeans for 8 weeks. Experimental diets were a control containing 27.4 % alfalfa silage, 22.5% corn silage, and 50.1% concentrate, and four diets with either tallow, raw soybean, extruded soybean, or roasted soybean added to provide 1.93% supplemental fat. Dry matter and NEL intakes were similar among treatments, while cows fed fat diets had significantly (P<0.05 high NEL intakes when compared to control with no fat. Supplemental fat, whether tallow or full fat soybeans increased milk production (1.89-2.45 kg/d; P<0.01 and FCM production (1.05-2.79; P<0.01. Milk fat yield and percentage of cows fed fat-supplemented diets were significantly (P<0.01 and P<0.05 respectively higher than control. Between fat-supplemented diets, roasted soybean caused highest milk fat yield and extruded soybean caused lowest milk fat yield. There was no significant effect of supplemental fat on the milk protein and lactose content and yield. Feed efficiency of fat-supplemented diets was significantly (P<0.01 higher than control. Body weight, body weight change and BCS (body condition score of cows, as well as energy balance and energy efficiency were similar between treatments. In conclusion, while there was no significant effect of fat sources on production response of cows, fat originating from heat-treated soybean help to minimize imported RUP (rumen undegradable protein sources level as fish meal in comparison with tallow and raw soybean oil. In the Current study, there was no statistical significance among nutritional values of oil from extruded soybeans and roasted soybeans.