Sample records for canid nematode angiostrongylus

  1. Draft genome of neurotropic nematode parasite Angiostrongylus cantonensis, causative agent of human eosinophilic meningitis.

    PubMed

    Yong, Hoi-Sen; Eamsobhana, Praphathip; Lim, Phaik-Eem; Razali, Rozaimi; Aziz, Farhanah Abdul; Rosli, Nurul Shielawati Mohamed; Poole-Johnson, Johan; Anwar, Arif

    2015-08-01

    Angiostrongylus cantonensis is a bursate nematode parasite that causes eosinophilic meningitis (or meningoencephalitis) in humans in many parts of the world. The genomic data from A. cantonensis will form a useful resource for comparative genomic and chemogenomic studies to aid the development of diagnostics and therapeutics. We have sequenced, assembled and annotated the genome of A. cantonensis. The genome size is estimated to be ?260Mb, with 17,280 genomic scaffolds, 91X coverage, 81.45% for complete and 93.95% for partial score based on CEGMA analysis of genome completeness. The number of predicted genes of ?300bp was 17,482. A total of 7737 predicted protein-coding genes of ?50 amino acids were identified in the assembled genome. Among the proteins of known function, kinases are the most abundant followed by transferases. The draft genome contains 34 excretory-secretory proteins (ES), a minimum of 44 Nematode Astacin (NAS) metalloproteases, 12 Homeobox (HOX) genes, and 30 neurotransmitters. The assembled genome size (260Mb) is larger than those of Pristionchus pacificus, Caenorhabditis elegans, Necator americanus, Caenorhabditis briggsae, Trichinella spiralis, Brugia malayi and Loa loa, but smaller than Haemonchus contortus and Ascaris suum. The repeat content (25%) is similar to H. contortus. The GC content (41.17%) is lower compared to P. pacificus (42.7%) and H. contortus (43.1%) but higher compared to C. briggsae (37.69%), A. suum (37.9%) and N. americanus (40.2%) while the scaffold N50 is 42,191. This draft genome will facilitate the understanding of many unresolved issues on the parasite and the disorder it causes. PMID:25910624

  2. Identification of Angiostrongylus cantonensis and other nematodes using the SSU rDNA in Achatina fulica populations of Metro Manila.

    PubMed

    Constantino-Santos, M A; Basiao, Z U; Wade, C M; Santos, B S; Fontanilla I, K C

    2014-06-01

    Angiostrongylus cantonensis is a parasitic nematode that causes eosinophilic meningitis in humans. Accidental infection occurs by consumption of contaminated intermediates, such as the giant African land snail, Achatina fulica. This study surveyed the presence of A. cantonensis juveniles in A. fulica populations from 12 sites in Metropolitan Manila, Philippines using the SSU rDNA. Fourteen distinct sequences from 226 nematodes were obtained; of these, two matched A. cantonensis and Ancylostoma caninum, respectively, with 100% identity. Exact identities of the remaining twelve sequences could not be determined due to low percent similarities. Of the sequenced nematodes, A. cantonensis occurred with the highest frequency (139 out of 226). Most of these (131 out of 139) were collected in just one area in Quezon City. Nematode infection of A. fulica in this area and two others from Makati and another area in Quezon City, respectively, were highest, combining for 95% of the total infection. Ancylostoma caninum, on the other hand, was detected in four different sites. A. caninum is a canine parasite, and this is the first report of the nematode in A. fulica. These results cause public health concerns as both A. cantonensis and A. caninum are zoonotic to humans. PMID:25134902

  3. Increased prevalence and geographic spread of the cardiopulmonary nematode Angiostrongylus vasorum in fox populations in Great Britain.

    PubMed

    Taylor, C S; Garcia Gato, R; Learmount, J; Aziz, N A; Montgomery, C; Rose, H; Coulthwaite, C L; McGarry, J W; Forman, D W; Allen, S; Wall, R; Morgan, E R

    2015-08-01

    The nematode Angiostrongylus vasorum is becoming more widely recorded globally, and is of increasing concern as a cause of disease in dogs. Apparent geographic spread is difficult to confirm due to a lack of standardized disease recording systems, increasing awareness among veterinary clinicians, and recent improvements in diagnostic technologies. This study examines the hypothesis that A. vasorum has spread in recent years by repeating the methods of a previous survey of the fox population. The hearts and lungs of 442 foxes from across Great Britain were collected and examined by dissection and flushing of the pulmonary circulation and microscopic inspection of tracheal scrapes. Sampling and parasite extraction methods were identical to an earlier survey in 2005 to ensure comparability. Prevalence of A. vasorum was 18·3% (exact binomial confidence bounds 14·9-22·3), compared with 7·3% previously (5·3-9·9, n = 546), and had increased significantly in most regions, e.g. 7·4% in the Northern UK (previously zero) and 50·8% in the south-east (previously 23·2%). Other nematodes identified were Crenosoma vulpis (prevalence 10·8%, CI 8·1-14·2) and Eucoleus aerophilus (31·6%, CI 27·3-36·2). These data support the proposal that A. vasorum has increased in prevalence and has spread geographically in Great Britain. PMID:26027539

  4. Detection of Angiostrongylus vasorum in Red Foxes (Vulpes vulpes) from Brandenburg, Germany.

    PubMed

    Härtwig, Vera; Schulze, Christoph; Barutzki, Dieter; Schaper, Roland; Daugschies, Arwid; Dyachenko, Viktor

    2015-08-01

    Angiostrongylus (A.) vasorum is a nematode that causes angiostrongylosis in domestic and wild canids. Red foxes (Vulpes vulpes) and raccoon dogs (Nyctereutes procyonoides) are suspected of providing a wildlife reservoir for A. vasorum infections in pet dogs. To obtain data on the occurrence of A. vasorum in wildlife, red fox and raccoon dog carcasses (hunted or found dead) were collected from January to September 2009 in the Federal State of Brandenburg, Germany. Lung tissue samples were subjected to DNA extraction and examined for the presence of A. vasorum DNA by means of real-time PCR. A. vasorum DNA was detected in 11 out of 122 (9.0 %) lungs of red foxes and in none of the lung samples of raccoon dogs. These data suggest that red foxes are a reservoir of A. vasorum infections for pet dogs in this area. PMID:26152419

  5. Molecular identification of novel intermediate host species of Angiostrongylus vasorum in Greater London.

    PubMed

    Patel, Zainab; Gill, A Christina; Fox, Mark T; Hermosilla, Carlos; Backeljau, Thierry; Breugelmans, Karin; Keevash, Esther; McEwan, Claudia; Aghazadeh, Mahdis; Elson-Riggins, Jocelyn G

    2014-12-01

    Angiostrongylus vasorum is a parasitic nematode that can cause serious and potentially fatal disease in dogs and other canids. The aim of this study was to determine the intermediate slug species infected in nature by sampling sites in Greater London and Hertfordshire located within a known hyperendemic region. Overall, A. vasorum larvae were recovered from 6/381 slugs (1.6%) by tissue digestion, and their identity was confirmed by PCR. Infected slugs originated from three different sites in the Greater London area: one in Waltham Forest and two in Bromley. Slugs parasitised by A. vasorum were identified by a combination of external morphological characteristics and molecular techniques and belonged to three different families: the Arionidae, the Milacidae and the Limacidae. This includes two new host records for the parasite: Arion distinctus and Tandonia sowerbyi. This is the first record of A. vasorum in the family Milacidae, indicating that the parasite has a broader intermediate host range than previously recognised. PMID:25195057

  6. Parasitological and hematological aspects of co-infection with Angiostrongylus vasorum and Ancylostoma caninum in dogs.

    PubMed

    Dracz, Ruth Massote; Mozzer, Lanuze Rose; Fujiwara, Ricardo Toshio; Lima, Walter dos Santos

    2014-02-24

    Dogs are frequently infected by one or more species of endoparasites, which can lead to secondary infections that cause high morbidity and death. In this context, 2 nematode species are of veterinary importance: Angiostrongylus vasorum, which is a parasite of the pulmonary artery and right ventricle in domestic and wild canids, and Ancylostoma caninum, which is a parasite of the small intestine in felids and domestic and wild canids. We used 20 mongrel dogs that were divided into groups and infected as follows: Group A included 5 uninfected dogs, Group B included 5 dogs infected with A. vasorum, Group C included 5 dogs infected with A. caninum, and Group D included 5 dogs co-infected with A. vasorum and A. caninum. Parasitological and hematological monitoring were performed. The counts of larvae and eggs shed in the feces varied throughout the collection period. Moreover, negativation was not observed in any of the infected groups. The animals in Group C had macrocytic and hypochromic anemia, whereas the animals in Group D had macrocytic and normochromic anemia. Infected dogs also presented with eosinophilia and lymphocytosis. These data from coproparasitological techniques provide an improved assessment of disease severity and a more thorough understanding of parasitism in the host. PMID:24373514

  7. Angiostrongylus species in wild carnivores in the Iberian Peninsula.

    PubMed

    Gerrikagoitia, X; Barral, M; Juste, R A

    2010-11-24

    A survey of Angiostrongylus parasites was carried out between 2003 and 2006 in wild carnivore species in the Basque Country (Northern Spain). Parasitological examination consisted in the dissection of heart and lungs for the extraction of adult worms. Nematodes were identified using morphometrical features and also PCR amplification and sequencing analysis. The animal species included in this study were Eurasian badger (Meles meles), Weasel (Mustela nivalis), Beech marten (Martes foina), Pine marten (Martes martes), Polecat (Mustela putorius), American mink (Mustela vison), Red fox (Vulpes vulpes), Wolf (Canis lupus), Wild cat (Felis silvestris), and Small-spotted genet (Genetta genetta). Angiostrongylus parasites were only found in foxes and badgers at prevalences of 33.3% and 24%, respectively. Identification of the nematodes by morphometrical features revealed that foxes were infected with A. vasorum while badgers were infected by a different species of Angiostrongylus most likely A. daskalovi. Sequencing data of the second internal transcribed spacer region of ribosomal DNA (ITS2) of isolates from each species confirmed the species difference. The high prevalence of Angiostrongylus found in the present survey, indicates that the wild cycle of two different species of Angiostrongylus is present in the Basque Country. To our knowledge this is the first report of A. daskalovi in the Iberian Peninsula. PMID:20728995

  8. Species of Angiostrongylus (Nematoda: Metastrongyloidea) in wildlife: A review

    PubMed Central

    Spratt, David M.

    2015-01-01

    Twenty-one species of Angiostrongylus plus Angiostrongylus sp. (Nematoda: Metastrongyloidea) are known currently in wildlife. These occur naturally in rodents, tupaiids, mephitids, mustelids, procyonids, felids, and canids, and aberrantly in a range of avian, marsupial and eutherian hosts including humans. Adults inhabit the pulmonary arteries and right atrium, ventricle and vena cava, bronchioles of the lung or arteries of the caecum and mesentery. All species pass first-stage larvae in the faeces of the host and all utilise slugs and/or aquatic or terrestrial snails as intermediate hosts. Gastropods are infected by ingestion or penetration of first-stage larvae; definitive hosts by ingestion of gastropods or gastropod slime. Transmission of at least one species may involve ingestion of paratenic hosts. Five developmental pathways are identified in these life cycles. Thirteen species, including Angiostrongylus sp., are known primarily from the original descriptions suggesting limited geographic distributions. The remaining species are widespread either globally or regionally, and are continuing to spread. Small experimental doses of infective larvae (ca. 20) given to normal or aberrant hosts are tolerated, although generally eliciting a granulomatous histopathological response; large doses (100–500 larvae) often result in clinical signs and/or death. Two species, A. cantonensis and A. costaricensis, are established zoonoses causing neurological and abdominal angiostrongliasis respectively. The zoonotic potential of A. mackerrasae, A. malaysiensis and A. siamensis particularly warrant investigation. Angiostrongylus cantonensis occurs in domestic animals, mammalian and avian wildlife and humans in the metropolitan areas of Brisbane and Sydney, Australia, where it has been suggested that tawny frogmouths and brushtail possums may serve as biosentinels. A major conservation issue is the devastating role A. cantonensis may play around zoos and fauna parks where captive rearing of endangered species programmes may exist and where Rattus spp. are invariably a problem. PMID:25853051

  9. Angiostrongylus cantonensis and Rat Lungworm Disease in Brazil

    PubMed Central

    de Oliveira Simões, Raquel; Fernandez, Monica Ammon; Júnior, Arnaldo Maldonado

    2013-01-01

    The metastrongyloid nematode genus Angiostrongylus includes 18 species, two of which are relevant from a medical standpoint, Angiostrongylus costaricensis and Angiostrongylus cantonensis. The first was described from Costa Rica in 1971 and causes abdominal angiostrongyliasis in the Americas, including in Brazil. Angiostrongylus cantonensis, first described in 1935 from Canton, China, is the causative agent of eosinophilic meningitis. The natural definitive hosts are rodents, and molluscs are the intermediate hosts. Paratenic or carrier hosts include crabs, freshwater shrimp, amphibians, flatworms, and fish. Humans become infected accidentally by ingestion of intermediate or paratenic hosts and the parasite does not complete the life cycle as it does in rats. Worms in the brain cause eosinophilic meningitis. This zoonosis, widespread in Southeast Asia and the Pacific islands, has now been reported from other regions. In the Americas there are records from the United States, Cuba, Jamaica, Brazil, Ecuador, and Haiti. In Brazil seven human cases have been reported since 2007 from the southeastern and northeastern regions. Epidemiological studies found infected specimens of Rattus norvegicus and Rattus rattus as well as many species of molluscs, including the giant African land snail, Achatina fulica, from various regions of Brazil. The spread of angiostrongyliasis is currently a matter of concern in Brazil. PMID:23901376

  10. Combined Serological Detection of Circulating Angiostrongylus vasorum Antigen and Parasite-specific Antibodies in Dogs from Hungary.

    PubMed

    Schnyder, Manuela; Schaper, Roland; Lukács, Zoltán; Hornok, Sándor; Farkas, Róbert

    2015-08-01

    The occurrence of the nematode Angiostrongylus vasorum, also known as the French heartworm, is increasingly being reported from various European countries. The adults of this parasite species live in the pulmonary arteries and right cardiac ventricle of wild canids and domestic dogs. Larval stages and eggs in the lungs induce inflammatory verminous pneumonia, causing severe respiratory disease in dogs. Furthermore, haematological and neurological signs and even death may occur. In Hungary, A. vasorum has been identified in red foxes, golden jackals and in two dogs and some slugs. In this first large-scale survey, 1247 sera from pet dogs were collected and tested by an ELISA for the detection of circulating antigen of A. vasorum and by a separate ELISA to detect specific antibodies against the parasite. A total of 1.36% (n = 17, 95 % confidence intervals, CI: 0.80 - 2.17 %) of the animals were positive in both ELISAs, while 1.76 % (n = 22, CI: 1.11 - 2.66 %) of the tested dogs were antigen-positive only and 2.73 % (n = 34, CI: 1.90 - 3.79 %) were positive for specific antibodies only. Regions with antigen- and antibodypositive animals overlapped and were distributed over nearly the whole sampled areas of the country. A considerable number of cases was observed in Budapest and also in the southern part of the country bordering Croatia, while in the most eastern part bordering Ukraine no positive samples were detected. These results confirm the endemic occurrence of A. vasorum in dogs originating from different parts of Hungary and the significant advantages of A. vasorum serology in epidemiological studies. PMID:26152415

  11. Filaroides osleri ( Oslerus osleri): Two case reports and a review of canid infections in North America

    Microsoft Academic Search

    Chaoqun Yao; Donal O’Toole; Mike Driscoll; Warner McFarland; Jonathan Fox; Todd Cornish; William Jolley

    2011-01-01

    Infections of domesticated dogs by a worldwide parasitic nematode Filaroides osleri (Oslerus osleri) lead to verminous tracheobronchitis that are often misdiagnosed clinically as kennel cough, due to infection with the bacterium Bordetella bronchiseptica. Diagnosis of two canine cases in Wyoming, USA prompted a search of the literature of canid infections in North America. Infections of domestic dogs are reported in

  12. On the diversity of mollusc intermediate hosts of Angiostrongylus costaricensis Morera & Cespedes, 1971 in southern Brazil.

    PubMed

    Teixeira, C G; Thiengo, S C; Thome, J W; Medeiros, A B; Camillo-Coura, L; Agostini, A A

    1993-01-01

    Veronicellid slugs are considered the most important intermediate hosts of Angiostrongylus costaricensis, an intra-arterial nematode of rodents. Studies undertaken in three localities in southern Brazil led to identification of molluscs other than veronicellid slugs as hosts of A. costaricensis: Limax maximus, Limax flavus and Bradybaena similaris. These data indicate a low host specificity of larval stages of A. costaricensis, as it has been reported to other congeneric species. PMID:8107609

  13. Environmental determinants of the spatial distribution of Angiostrongylus vasorum, Crenosoma vulpis and Eucoleus aerophilus in Hungary.

    PubMed

    Tolnai, Z; Széll, Z; Sréter, T

    2015-01-30

    Angiostrongylus vasorum, Crenosoma vulpis and Eucoleus aerophilus (syn. Capillaria aerophila) are the most important lungworm species infecting wild and domesticated canids in Europe. To investigate the spatial distribution of these parasites and the factors influencing their circulation in the fox populations, 937 red foxes (Vulpes vulpes) were tested for lungworm infection in Hungary. The prevalence of A. vasorum, C. vulpis and E. aerophilus infection was high (17.9, 24.6 and 61.7%). The distribution pattern of infection in foxes and the relationship of this pattern with landscape and climate was analyzed by geographic information system. Based on the analysis, the annual precipitation was the major determinant of the spatial distribution of A. vasorum and C. vulpis and E. aerophilus. Nevertheless, the mean annual temperature also influenced the distribution of A. vasorum and E. aerophilus. The positive relationship with annual precipitation and the negative relationship with mean annual temperature can be attributed to the sensitivity of larvae, eggs and intermediate hosts (snails and slugs) of lungworms for desiccation. Based on the highly clumped distribution of A. vasorum and C. vulpis, the indirect life cycle (larvae, slugs and snails) of these parasites seems to be particularly sensitive for environmental effects. The distribution of E. aerophilus was considerably less clumped indicating a lower sensitivity of the direct life cycle (eggs) of this parasite for environmental factors. Based on these results, lungworm infections in canids including dogs can be expected mainly in relatively wet and cool areas. PMID:25547643

  14. High throughput sequencing of the Angiostrongylus cantonensis genome: a parasite spreading worldwide.

    PubMed

    Morassutti, Alessandra L; Perelygin, Andrey; DE Carvalho, Marcos O; Lemos, Leandro Nascimento; Pinto, Paulo Marcos; Frace, Mike; Wilkins, Patricia P; Graeff-Teixeira, Carlos; DA Silva, Alexandre J

    2013-09-01

    Angiostrongylus cantonensis is a parasitic nematode of rodents and a leading aetiological agent of eosinophilic meningitis in humans. Definitive diagnosis is difficult, often relying on immunodiagnostic methods which utilize crude antigens. New immunodiagnostic methods based on recombinant proteins are being developed, and ideally these methods would be made available worldwide. Identification of diagnostic targets, as well as studies on the biology of the parasite, are limited by a lack of molecular information on Angiostrongylus spp. available in databases. In this study we present data collected from DNA random high-throughput sequencing together with proteomic analyses and a cDNA walking methodology to identify and obtain the nucleotide or amino acid sequences of unknown immunoreactive proteins. 28 080 putative ORFs were obtained, of which 3371 had homology to other deposited protein sequences. Using the A. cantonensis genomic sequences, 156 putative ORFs, matching peptide sequences obtained from previous proteomic studies, were considered novel, with no homology to existing sequences. Full-length coding sequences of eight antigenic target proteins were obtained. In this study we generated not only the complete nucleotide sequences of the antigenic protein targets but also a large amount of genomic data which may help facilitate future genomic, proteomic, transcriptomic or metabolomic studies on Angiostrongylus. PMID:23863082

  15. Canine parvovirus infection in South American canids.

    PubMed

    Mann, P C; Bush, M; Appel, M J; Beehler, B A; Montali, R J

    1980-11-01

    Canine parvovirus (CPV) infections occurred in 5 of 35 South American canids at the Department of Conservation (DC), a breeding facility of the National Zoological Park in Front Royal, Va. The clinical signs were anorexia, lethargy, diarrhea, and vomiting. Three of the affected canids survived and had high hemagglutination-inhibition titers to CPV in the recovery period. Necropsy of the 2 that died revealed extensive necrosis of the intestinal mucosa; CPV particles were observed by electron microscopy in the intestinal contents of both animals. Six of the 30 canids that remained healthy had high hemagglutination-inhibition titers to CPV prior to the episode of illness, indicating earlier subclinical exposure. Pet dogs belonging to DC personnel that were screened as a possible source of the infection had no evidence of disease. All canids (including pet dogs) on the DC grounds were vaccinated repeatedly with a killed feline panleukopenia virus product after the episode, with little or no effect on existing titers. PMID:7451312

  16. Angiostrongylus cantonensis in Introduced Gastropods in Southern Florida.

    PubMed

    Stockdale-Walden, Heather D; Slapcinsky, John; Qvarnstrom, Yvonne; McIntosh, Antoinette; Bishop, Henry S; Rosseland, Brent

    2015-04-01

    Angiostrongylus cantonensis , the rat lungworm, is a zoonotic, parasitic nematode that uses the rat as a definitive host and gastropods as intermediate hosts. It is prevalent in parts of Asia, the Pacific islands, and the Caribbean. In the United States, A. cantonensis is established in Hawaii and in recent years has been reported in Alabama, California, Louisiana, and Florida, where it has been found in the reintroduced Lissachatina fulica (also known as Achatina fulica), the giant African snail that was once eradicated from the state. Since 2004, A. cantonensis has been identified as the causative agent for 2 non-human primate deaths in Florida, one attributed to ingestion of the snail Zachrysia provisoria. Our study further supports the presence of A. cantonensis in Z. provisoria in Florida and identifies 2 additional introduced terrestrial snails, Bradybaena similaris and Alcadia striata, that serve as intermediate hosts for A. cantonensis , as well as evidence of rat infection, in southern Florida. The finding of both definitive and intermediate hosts suggests that A. cantonensis may be established in south Florida. PMID:25564891

  17. First provincial survey of Angiostrongylus cantonensis in Guangdong Province, China.

    PubMed

    Deng, Zhuo-Hui; Zhang, Qi-Ming; Huang, Shao-Yu; Jones, Jeffrey L

    2012-01-01

    The rat lungworm Angiostrongylus cantonensis is a zoonotic nematode with a wide distribution. We report the first provincial survey of the prevalence of A. cantonensis infection among wild rodents and snails in Guangdong Province, China. A total of 2929 Pomacea canaliculata and 1354 Achatina fulica were collected from fields in 22 survey sites with a larval infection rates ranging from 0-26.6% to 0-45.4%. In addition, 114 Cipangopaludina sp and 252 Bellamya sp were bought from markets; larvae were found only in Bellamya snails from two survey sites with an infection rate of 1.4% (1/70) and 3.3% (3/91), respectively. Four hundred and ninety-one rodents were captured in nine sites (Rattus norvegicus, R. flavipectus, Suncus murinus, Mus musculus, Bandicota indica, R. losea and R. rattus). Adult worms were found in R. norvegicus, R. flavipectus and Bandicota indica. Our survey revealed a wide distribution of A. cantonensis and its intermediate hosts P. canaliculata and A. fulica in Guangdong. The prevalence of A. cantonensis in wild snails and rats poses a substantial risk for angiostrongyliasis in humans. PMID:21906215

  18. Neuroparasitic Infections: Nematodes

    PubMed Central

    Walker, M.D.; Zunt, J.R.

    2009-01-01

    Globalization has produced an increase in the number of people at risk for contracting parasitic infection. Central nervous system infection by nematodal parasites can be devastating. Early recognition and treatment of infection can significantly decrease morbidity of the parasitic infection, as well as the risk of secondary superinfection. The clinical presentation, diagnosis, and treatment for five of the more common nematodal infections of the nervous system—Angiostrongylus spp., Baylisacaris procyonis, Gnathostoma spinigerum, Strongyloides stercoralis, and Toxocara spp.—is reviewed. Objectives On completion of this article, the reader should be able to summarize the clinical presentation, diagnosis, and treatment of the common nematodal infections of the nervous system. Accreditation The Indiana University School of Medicine is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. Credit The Indiana University School of Medicine designates this educational activity for a maximum of 1 Category 1 credit toward the AMA Physicians Recognition Award. Each physician should claim only those credits that he/she actually spent in the educational activity. Disclosure Statements of disclosure have been obtained regarding the authors’ relevant financial relationships. The authors have nothing to disclose. PMID:16170738

  19. Diverse gastropod hosts of Angiostrongylus cantonensis, the rat lungworm, globally and with a focus on the Hawaiian Islands.

    PubMed

    Kim, Jaynee R; Hayes, Kenneth A; Yeung, Norine W; Cowie, Robert H

    2014-01-01

    Eosinophilic meningitis caused by the parasitic nematode Angiostrongylus cantonensis is an emerging infectious disease with recent outbreaks primarily in tropical and subtropical locations around the world, including Hawaii. Humans contract the disease primarily through ingestion of infected gastropods, the intermediate hosts of Angiostrongylus cantonensis. Effective prevention of the disease and control of the spread of the parasite require a thorough understanding of the parasite's hosts, including their distributions, as well as the human and environmental factors that contribute to transmission. The aim of this study was to screen a large cross section of gastropod species throughout the main Hawaiian Islands to determine which act as hosts of Angiostrongylus cantonensis and to assess the parasite loads in these species. Molecular screening of 7 native and 30 non-native gastropod species revealed the presence of the parasite in 16 species (2 native, 14 non-native). Four of the species tested are newly recorded hosts, two species introduced to Hawaii (Oxychilus alliarius, Cyclotropis sp.) and two native species (Philonesia sp., Tornatellides sp.). Those species testing positive were from a wide diversity of heterobranch taxa as well as two distantly related caenogastropod taxa. Review of the global literature showed that many gastropod species from 34 additional families can also act as hosts. There was a wide range of parasite loads among and within species, with an estimated maximum of 2.8 million larvae in one individual of Laevicaulis alte. This knowledge of the intermediate host range of Angiostrongylus cantonensis and the range of parasite loads will permit more focused efforts to detect, monitor and control the most important hosts, thereby improving disease prevention in Hawaii as well as globally. PMID:24788772

  20. Diverse Gastropod Hosts of Angiostrongylus cantonensis, the Rat Lungworm, Globally and with a Focus on the Hawaiian Islands

    PubMed Central

    Kim, Jaynee R.; Hayes, Kenneth A.; Yeung, Norine W.; Cowie, Robert H.

    2014-01-01

    Eosinophilic meningitis caused by the parasitic nematode Angiostrongylus cantonensis is an emerging infectious disease with recent outbreaks primarily in tropical and subtropical locations around the world, including Hawaii. Humans contract the disease primarily through ingestion of infected gastropods, the intermediate hosts of Angiostrongylus cantonensis. Effective prevention of the disease and control of the spread of the parasite require a thorough understanding of the parasite's hosts, including their distributions, as well as the human and environmental factors that contribute to transmission. The aim of this study was to screen a large cross section of gastropod species throughout the main Hawaiian Islands to determine which act as hosts of Angiostrongylus cantonensis and to assess the parasite loads in these species. Molecular screening of 7 native and 30 non-native gastropod species revealed the presence of the parasite in 16 species (2 native, 14 non-native). Four of the species tested are newly recorded hosts, two species introduced to Hawaii (Oxychilus alliarius, Cyclotropis sp.) and two native species (Philonesia sp., Tornatellides sp.). Those species testing positive were from a wide diversity of heterobranch taxa as well as two distantly related caenogastropod taxa. Review of the global literature showed that many gastropod species from 34 additional families can also act as hosts. There was a wide range of parasite loads among and within species, with an estimated maximum of 2.8 million larvae in one individual of Laevicaulis alte. This knowledge of the intermediate host range of Angiostrongylus cantonensis and the range of parasite loads will permit more focused efforts to detect, monitor and control the most important hosts, thereby improving disease prevention in Hawaii as well as globally. PMID:24788772

  1. Eosinophilic meningitis caused by Angiostrongylus cantonensis: an emergent disease in Brazil

    PubMed Central

    Morassutti, Alessandra Loureiro; Thiengo, Silvana Carvalho; Fernandez, Monica; Sawanyawisuth, Kittisak; Graeff-Teixeira, Carlos

    2014-01-01

    Eosinophilic meningitis (EoM) is an acute disease that affects the central nervous system. It is primarily caused by infection with the nematode Angiostrongylus cantonensis. This infection was previously restricted to certain Asian countries and the Pacific Islands, but it was first reported in Brazil in 2007. Since then, intermediate and definitive hosts infected with A. cantonensis have been identified within the urban areas of many states in Brazil, including those in the northern, northeastern, southeastern and southern regions. The goals of this review are to draw the attention of the medical community and health centres to the emergence of EoM in Brazil, to compile information about several aspects of the human infection and mode of transmission and to provide a short protocol of procedures for the diagnosis of this disease. PMID:25075779

  2. Proteolytic activity in the adult and larval stages of the human roundworm parasite Angiostrongylus costaricensis.

    PubMed

    Rebello, Karina Mastropasqua; Siqueira, Caroline Reis de; Ribeiro, Erika Louise; Valente, Richard Hemmi; Mota, Ester Maria; Perales, Jonas; Neves-Ferreira, Ana Gisele da Costa; Lenzi, Henrique Leonel

    2012-09-01

    Angiostrongylus costaricensis is a nematode that causes abdominal angiostrongyliasis, a widespread human parasitism in Latin America. This study aimed to characterize the protease profiles of different developmental stages of this helminth. First-stage larvae (L1) were obtained from the faeces of infected Sigmodon hispidus rodents and third-stage larvae (L3) were collected from mollusks Biomphalaria glabrata previously infected with L1. Adult worms were recovered from rodent mesenteric arteries. Protein extraction was performed after repeated freeze-thaw cycles followed by maceration of the nematodes in 40 mM Tris base. Proteolysis of gelatin was observed by zymography and found only in the larval stages. In L3, the gelatinolytic activity was effectively inhibited by orthophenanthroline, indicating the involvement of metalloproteases. The mechanistic class of the gelatinases from L1 could not be precisely determined using traditional class-specific inhibitors. Adult worm extracts were able to hydrolyze haemoglobin in solution, although no activity was observed by zymography. This haemoglobinolytic activity was ascribed to aspartic proteases following its effective inhibition by pepstatin, which also inhibited the haemoglobinolytic activity of L1 and L3 extracts. The characterization of protease expression throughout the A. costaricensis life cycle may reveal key factors influencing the process of parasitic infection and thus foster our understanding of the disease pathogenesis. PMID:22990964

  3. Central nervous system manifestations of Angiostrongylus cantonensis infection.

    PubMed

    Martins, Yuri C; Tanowitz, Herbert B; Kazacos, Kevin R

    2015-01-01

    Over 20 species of Angiostrongylus have been described from around the world, but only Angiostrongylus cantonensis has been confirmed to cause central nervous system disease in humans. A neurotropic parasite that matures in the pulmonary arteries of rats, A. cantonensis is the most common cause of eosinophilic meningitis in southern Asia and the Pacific and Caribbean islands. The parasite can also cause encephalitis/encephalomyelitis and rarely ocular angiostrongyliasis. The present paper reviews the life cycle, epidemiology, pathogenesis, clinical features, diagnosis, treatment, prevention and prognosis of A. cantonesis infection. Emphasis is given on the spectrum of central nervous system manifestations and disease pathogenesis. PMID:25312338

  4. Nematode Songs

    NSDL National Science Digital Library

    Merrifield, Kathy.

    Nematode Songs is a wonderful, straightforward resource maintained by Nematologist Kathy Merrifield of Oregon State University, who makes light of these microscopic worms and parasites. A collection of 15 titles, including such notables as "Good King Nematode," "The Golden Sun" and "The Parasitic Nematode Rag," offer clever (and nematode-ish) lyrics to familiar songs. An option to sing along is included (requires MIDI sound), and each feature includes sheet music as well as complete lyrics. For the more serious, links to scientific nematode resources are provided at the bottom of the page.

  5. Angiostrongylus cantonensis: morphological and behavioral investigation within the freshwater snail Pomacea canaliculata.

    PubMed

    Lv, Shan; Zhang, Yi; Liu, He-Xiang; Zhang, Chao-Wei; Steinmann, Peter; Zhou, Xiao-Nong; Utzinger, Jürg

    2009-06-01

    An infection with Angiostrongylus cantonensis, the main causative agent for human eosinophilic encephalitis, can be acquired through the consumption of the freshwater snail Pomacea canaliculata. This snail also provides a suitable model to study the developmental morphology and behavior of A. cantonensis larvae, facilitated by the snail's distinct lung structure. We used microanatomy for studying the natural appearance and behavior of A. cantonensis larvae while developing within P. canaliculata. The distribution of refractile granules in the larval body and characteristic head structures changed during the developmental cycle. Two well-developed, rod-like structures with expanded knob-like tips at the anterior part were observed under the buccal cavity as early as the late second developmental stage. A "T"-shaped structure at the anterior end and its tenacity distinguished the outer sheath from that shed during the second molting. Early first-stage larvae obtained from fresh rat feces are free moving and characterized by a coiled tail, whereas a mellifluous "Q"-movement was the behavioral trait of third-stage A. cantonensis larvae outside the host tissue. In combination, the distribution of refractive granules, distinct head features, variations in sheaths, and behavioral characteristics can be utilized for differentiation of larval stages, and for distinguishing A. cantonensis larvae from those of other free-living nematodes. PMID:19172296

  6. Epidemiological survey of Angiostrongylus vasorum in dogs and slugs around a new endemic focus in Scotland.

    PubMed

    Helm, J; Roberts, L; Jefferies, R; Shaw, S E; Morgan, E R

    2015-07-11

    The nematode parasite Angiostrongylus vasorum is an increasingly important cause of respiratory and other diseases in dogs. Geographical spread from previously limited endemic foci has occurred rapidly. This paper investigates parasite epidemiology around the location of the first reported case in Scotland in 2009: by detection of A vasorum-specific DNA in gastropod intermediate hosts, and in dogs circulating DNA and specific antibodies, and first stage larvae in faeces. Overall prevalence in gastropods was 6.7 per cent (16/240), with parasite DNA found in slugs in the Arion ater and Arion hortensis species aggregates and the snail Helix aspersa (syn. Cornu aspersum). Of 60 dogs presenting with clinical signs compatible with angiostrongylosis, none tested positive using PCR on peripheral blood or Baermann test on faeces, and none of 35 tested for circulating anti-A vasorum antibodies were positive. PCR prevalence in gastropods was highest (11 per cent) in the park frequented by the canine angiostrongylosis index case. Molecular survey for infection in gastropods is a potentially informative and efficient method for characterising the distribution of A vasorum and therefore local risk of canine infection. However, there appears to be a complex relationship between prevalence in gastropods and emergence of canine clinical disease, which requires further work to advance understanding of parasite transmission and geographical disease spread. PMID:25934261

  7. Phenantroline, lovastatin, and mebendazole do not inhibit oviposition in the murine experimental infection with Angiostrongylus costaricensis.

    PubMed

    Bohrer Mentz, Márcia; Dallegrave, Eliane; Agostini, Aventino; Graeff-Teixeira, Carlos

    2007-01-01

    Abdominal angiostrongyliasis is a zoonotic infection produced by a metastrongylid intra-arterial nematode, Angiostrongylus costaricensis. Human accidental infection may result in abdominal lesions. The presence of the eggs in the tissues plays an essential role in morbidity of abdominal angiostrongyliasis. The objective of this study is to evaluate and compare the effects of lovastatin, phenanthrolin, and mebendazole on oviposition of A. costaricensis in a murine experimental model. Each group of 12 male Swiss mice (Mus musculus) was orally infected with 10 L3 of the "Santa Rosa" strain of A. costaricensis. Two control groups were established: (1) mice were infected and not treated; (2) noninfected and nontreated animals. The experimental groups received (1) lovastatin TL), at a daily dose of 250 mg/kg for 10 consecutive days 16 days after infection; (2) phenanthroline at a daily dose of 20 mg/kg for 5 consecutive days 21 days after infection; and (3) mebendazole at a daily dose of 5 mg/kg for 5 consecutive days 21 days after infection. There was no significant inhibition of oviposition for lovastatin- and mebendazole-treated animals, whereas phenanthroline was associated with the lowest averages of larviposition per postinfection day and significant reduction of mortality. PMID:16944203

  8. Kin encounter rate and inbreeding avoidance in canids

    USGS Publications Warehouse

    Geffen, Eli; Kam, Michael; Hefner, Reuven; Hersteinsson, Pall; Angerbjorn, Anders; Dalen, Love; Fuglei, Eva; Noren, Karin; Adams, Jennifer R.; Vicetich, John; Meier, Thomas J.; Mech, L.D.; VonHoldt, Bridgett M.; Stahler, Daniel R.; Wayne, Robert K.

    2011-01-01

    Mating with close kin can lead to inbreeding depression through the expression of recessive deleterious alleles and loss of heterozygosity. Mate selection may be affected by kin encounter rate, and inbreeding avoidance may not be uniform but associated with age and social system. Specifically, selection for kin recognition and inbreeding avoidance may be more developed in species that live in family groups or breed cooperatively. To test this hypothesis, we compared kin encounter rate and the proportion of related breeding pairs in noninbred and highly inbred canid populations. The chance of randomly encountering a full sib ranged between 1–8% and 20–22% in noninbred and inbred canid populations, respectively. We show that regardless of encounter rate, outside natal groups mates were selected independent of relatedness. Within natal groups, there was a significant avoidance of mating with a relative. Lack of discrimination against mating with close relatives outside packs suggests that the rate of inbreeding in canids is related to the proximity of close relatives, which could explain the high degree of inbreeding depression observed in some populations. The idea that kin encounter rate and social organization can explain the lack of inbreeding avoidance in some species is intriguing and may have implications for the management of populations at risk.

  9. Kin encounter rate and inbreeding avoidance in canids

    USGS Publications Warehouse

    Geffen, E.; Kam, M.; Hefner, R.; Hersteinsson, P.; Angerbjorn, A.; Dalen, L.; Fuglei, E.; Noren, K.; Adams, J.R.; Vucetich, J.; Meier, T.J.; Mech, L.D.; Vonholdt, B.M.; Stahler, D.R.; Wayne, R.K.

    2011-01-01

    Mating with close kin can lead to inbreeding depression through the expression of recessive deleterious alleles and loss of heterozygosity. Mate selection may be affected by kin encounter rate, and inbreeding avoidance may not be uniform but associated with age and social system. Specifically, selection for kin recognition and inbreeding avoidance may be more developed in species that live in family groups or breed cooperatively. To test this hypothesis, we compared kin encounter rate and the proportion of related breeding pairs in noninbred and highly inbred canid populations. The chance of randomly encountering a full sib ranged between 1-8% and 20-22% in noninbred and inbred canid populations, respectively. We show that regardless of encounter rate, outside natal groups mates were selected independent of relatedness. Within natal groups, there was a significant avoidance of mating with a relative. Lack of discrimination against mating with close relatives outside packs suggests that the rate of inbreeding in canids is related to the proximity of close relatives, which could explain the high degree of inbreeding depression observed in some populations. The idea that kin encounter rate and social organization can explain the lack of inbreeding avoidance in some species is intriguing and may have implications for the management of populations at risk. ?? 2011 Blackwell Publishing Ltd.

  10. Larvicidal activities of ginger ( Zingiber officinale) against Angiostrongylus cantonensis

    Microsoft Academic Search

    Rong-Jyh Lin; Chung-Yi Chen; Li-Yu Chung; Chuan-Min Yen

    2010-01-01

    In this study, we investigated the anthelmintic activity of [6]-gingerol, [10]-shogaol, [10]-gingerol, [6]-shogaol and hexahydrocurcumin, a constituent isolate from the roots of ginger (Zingiber officinale), for the parasite Angiostrongylus cantonensis. This study found that the above constituents killed A. cantonensis larvae or reduced their spontaneous movements in a time- and dose-dependent manner. The larvicidal effect or ability to halt spontaneous

  11. Respiratory and olfactory turbinal size in canid and arctoid carnivorans

    PubMed Central

    Green, Patrick A; Valkenburgh, Blaire; Pang, Benison; Bird, Deborah; Rowe, Timothy; Curtis, Abigail

    2012-01-01

    Within the nasal cavity of mammals is a complex scaffold of paper-thin bones that function in respiration and olfaction. Known as turbinals, the bones greatly enlarge the surface area available for conditioning inspired air, reducing water loss, and improving olfaction. Given their functional significance, the relative development of turbinal bones might be expected to differ among species with distinct olfactory, thermoregulatory and/or water conservation requirements. Here we explore the surface area of olfactory and respiratory turbinals relative to latitude and diet in terrestrial Caniformia, a group that includes the canid and arctoid carnivorans (mustelids, ursids, procyonids, mephitids, ailurids). Using high-resolution computed tomography x-ray scans, we estimated respiratory and olfactory turbinal surface area and nasal chamber volume from three-dimensional virtual models of skulls. Across the Caniformia, respiratory surface area scaled isometrically with estimates of body size and there was no significant association with climate, as estimated by latitude. Nevertheless, one-on-one comparisons of sister taxa suggest that arctic species may have expanded respiratory turbinals. Olfactory surface area scaled isometrically among arctoids, but showed positive allometry in canids, reflecting the fact that larger canids, all of which are carnivorous, had relatively greater olfactory surface areas. In addition, among the arctoids, large carnivorous species such as the polar bear (Ursus maritimus) and wolverine (Gulo gulo) also displayed enlarged olfactory turbinals. More omnivorous caniform species that feed on substantial quantities of non-vertebrate foods had less expansive olfactory turbinals. Because large carnivorous species hunt widely dispersed prey, an expanded olfactory turbinal surface area may improve a carnivore's ability to detect prey over great distances using olfactory cues. PMID:23035637

  12. Linkage Disequilibrium and Demographic History of Wild and Domestic Canids

    PubMed Central

    Gray, Melissa M.; Granka, Julie M.; Bustamante, Carlos D.; Sutter, Nathan B.; Boyko, Adam R.; Zhu, Lan; Ostrander, Elaine A.; Wayne, Robert K.

    2009-01-01

    Assessing the extent of linkage disequilibrium (LD) in natural populations of a nonmodel species has been difficult due to the lack of available genomic markers. However, with advances in genotyping and genome sequencing, genomic characterization of natural populations has become feasible. Using sequence data and SNP genotypes, we measured LD and modeled the demographic history of wild canid populations and domestic dog breeds. In 11 gray wolf populations and one coyote population, we find that the extent of LD as measured by the distance at which r2 = 0.2 extends <10 kb in outbred populations to >1.7 Mb in populations that have experienced significant founder events and bottlenecks. This large range in the extent of LD parallels that observed in 18 dog breeds where the r2 value varies from ?20 kb to >5 Mb. Furthermore, in modeling demographic history under a composite-likelihood framework, we find that two of five wild canid populations exhibit evidence of a historical population contraction. Five domestic dog breeds display evidence for a minor population contraction during domestication and a more severe contraction during breed formation. Only a 5% reduction in nucleotide diversity was observed as a result of domestication, whereas the loss of nucleotide diversity with breed formation averaged 35%. PMID:19189949

  13. Angiostrongylus costaricensis and the intermediate hosts: observations on elimination of L3 in the mucus and inoculation of L1 through the tegument of mollucs.

    PubMed

    Bonetti, V C; Graeff-Teixeira, C

    1998-01-01

    Human accidental infection with Angiostrongylus costaricensis may result in abdominal disease of varied severity. Slugs from the Veronicellidae family are the main intermediate hosts for this parasitic nematode of rodents. Phyllocaulis variegatus, Phyllocaulis soleiformis and Phyllocaulis boraceiensis were experimentally infected to describe the kinetics of L3 elimination in the mucus secretions of those veronicelid species. A maximum of 2 L3/g/day was found in the mucus, while the number of L3 isolated from the fibromuscular tissues varied from 14 to 448. Productive infection was established by inoculations in the hyponotum or in the body cavity, through the tegument. Intra-cavity injection is a less complex procedure and permits a better control of inocula. A preliminary trial to titrate the infective dosis for P. variegatus indicated that inocula should range between 1000 and 5000 L1. The data also confirmed the importance of P. variegatus as an intermediate host of A. costaricensis. PMID:9612020

  14. Angiostrongylus cantonensis: Scanning Electron Microscopic Observations on the Cuticle of Moulting Larvae

    PubMed Central

    Zeng, Xin; Wei, Jie; Wang, Juan; Wu, Feng; Fung, Feng; Wu, Xiaoying; Sun, Xi; Zheng, Huanqing

    2013-01-01

    Angiostrongylus cantonensis is a parasitic nematode that needs to develop in different hosts in different larval stages. Freshwater snails, such as Pomacea canaliculata, are the intermediate host, and rats are the definitive host. Periodic shedding of the cuticle (moulting) is an important biological process for the survival and development of the parasite in the intermediate and definitive hosts. However, there are few studies on the cuticle alterations between different stages of this parasite. In this study, we observed the ultrastructural appearance and changes of the cuticle of the 2nd/3rd stage larvae (L2/L3) and the 3rd/4th stage larvae (L3/L4) using a scanning electron microscope. We also first divided L2/L3 into late L2 and early L3. The late L2 lacked alae, but possessed a pull-chain-like fissure. Irregular alignment of spherical particles on the cuticle were noted compared to the L3. Alae appeared in the early L3. The old cuticle turned into a thin film-like structure which adhered to the new cuticle, and spherical particles were seen regularly arranged on the surface of this structure. Regular rectangular cavities were found on the surface of L3/L4. The caudal structure of L3/L4 was much larger than that of L3, but caudal inflation, such as seen in L4, was not observed. These results are the first to reveal the ultrastructural changes of the cuticle of A. cantonensis before and after moulting of L2/L3 and L3/L4. PMID:24516266

  15. Angiostrongylus cantonensis: scanning electron microscopic observations on the cuticle of moulting larvae.

    PubMed

    Zeng, Xin; Wei, Jie; Wang, Juan; Wu, Feng; Fung, Feng; Wu, Xiaoying; Sun, Xi; Zheng, Huanqing; Lv, Zhiyue; Wu, Zhongdao

    2013-12-01

    Angiostrongylus cantonensis is a parasitic nematode that needs to develop in different hosts in different larval stages. Freshwater snails, such as Pomacea canaliculata, are the intermediate host, and rats are the definitive host. Periodic shedding of the cuticle (moulting) is an important biological process for the survival and development of the parasite in the intermediate and definitive hosts. However, there are few studies on the cuticle alterations between different stages of this parasite. In this study, we observed the ultrastructural appearance and changes of the cuticle of the 2nd/3rd stage larvae (L2/L3) and the 3rd/4th stage larvae (L3/L4) using a scanning electron microscope. We also first divided L2/L3 into late L2 and early L3. The late L2 lacked alae, but possessed a pull-chain-like fissure. Irregular alignment of spherical particles on the cuticle were noted compared to the L3. Alae appeared in the early L3. The old cuticle turned into a thin film-like structure which adhered to the new cuticle, and spherical particles were seen regularly arranged on the surface of this structure. Regular rectangular cavities were found on the surface of L3/L4. The caudal structure of L3/L4 was much larger than that of L3, but caudal inflation, such as seen in L4, was not observed. These results are the first to reveal the ultrastructural changes of the cuticle of A. cantonensis before and after moulting of L2/L3 and L3/L4. PMID:24516266

  16. A Shared System of Representation Governing Quantity Discrimination in Canids

    PubMed Central

    Baker, Joseph M.; Morath, Justice; Rodzon, Katrina S.; Jordan, Kerry E.

    2012-01-01

    One way to investigate the evolution of cognition is to compare the abilities of phylogenetically related species. The domestic dog (Canis lupus familiaris), for example, still shares cognitive abilities with the coyote (Canis latrans). Both of these canids possess the ability to make psychophysical “less/more” discriminations of food based on quantity. Like many other species including humans, this ability is mediated by Weber’s Law: discrimination of continuous quantities is dependent on the ratio between the two quantities. As two simultaneously presented quantities of food become more similar, choice of the large or small option becomes random in both dogs and coyotes. It remains unknown, however, whether these closely related species within the same family – one domesticated, and one wild – make such quantitative comparisons with comparable accuracy. Has domestication honed or diminished this quantitative ability? Might different selective and ecological pressures facing coyotes drive them to be more or less able to accurately represent and discriminate food quantity than domesticated dogs? This study is an effort to elucidate this question concerning the evolution of non-verbal quantitative cognition. Here, we tested the quantitative discrimination ability of 16 domesticated dogs. Each animal was given nine trials in which two different quantities of food were simultaneously displayed to them. The domesticated dogs’ performance on this task was then compared directly to the data from 16 coyotes’ performance on this same task reported by Baker et al. (2011). The quantitative discrimination abilities between the two species were strikingly similar. Domesticated dogs demonstrated similar quantitative sensitivity as coyotes, suggesting that domestication may not have significantly altered the psychophysical discrimination abilities of canids. Instead, this study provides further evidence for similar non-verbal quantitative abilities across multiple species. PMID:23060847

  17. Effects of washing produce contaminated with the snail and slug hosts of Angiostrongylus cantonensis with three common household solutions.

    PubMed

    Yeung, Norine W; Hayes, Kenneth A; Cowie, Robert H

    2013-06-01

    The emerging infectious disease angiostrongyliasis (rat lungworm disease) is caused by ingesting snails and slugs infected by the nematode Angiostrongylus cantonensis. The definitive hosts of A. cantonensis are rats and the obligatory intermediate hosts are slugs and snails. Many cases result from accidentally ingesting infected snails or slugs on produce (eg, lettuce). This study assessed three readily available household products as washing solutions for removing snails and slugs from produce (romaine lettuce) to lower the probability of accidentally ingesting them. The solutions were acetic acid (vinegar), sodium hypochlorite (bleach), and sodium chloride (domestic salt). Snail and slug species known to be intermediate hosts and that are common in the Hawaiian Islands were used in the experiments: the alien snail Succinea tenella, the alien semi-slug Parmarion martensi, and the alien slugs Veronicella cubensis and Deroceras laeve. None of the products was any more effective than washing and rinsing with tap water alone. Most snails and slugs were removed after treatment but some remained on the lettuce even after washing and rinsing the produce. Only washing, rinsing, and then rinsing each leaf individually resulted in complete removal of all snails and slugs. The study did not address removal of any remaining slime left by the snails and slugs, nor did it address killing of worms. PMID:23901391

  18. Identification and characterisation of microRNAs in young adults of Angiostrongylus cantonensis via a deep-sequencing approach

    PubMed Central

    Chang, Shih-Hsin; Tang, Petrus; Lai, Cheng-Hung; Kuo, Ming-Ling; Wang, Lian-Chen

    2013-01-01

    Angiostrongylus cantonensis is an important causative agent of eosinophilic meningitis and eosinophilic meningoencephalitis in humans. MicroRNAs (miRNAs) are small non-coding RNAs that participate in a wide range of biological processes. This study employed a deep-sequencing approach to study miRNAs from young adults of A. cantonensis. Based on 16,880,456 high-quality reads, 252 conserved mature miRNAs including 10 antisense miRNAs that belonging to 90 families, together with 10 antisense miRNAs were identified and characterised. Among these sequences, 53 miRNAs from 25 families displayed 50 or more reads. The conserved miRNA families were divided into four groups according to their phylogenetic distribution and a total of nine families without any members showing homology to other nematodes or adult worms were identified. Stem-loop real-time polymerase chain reaction analysis of aca-miR-1-1 and aca-miR-71-1 demonstrated that their level of expression increased dramatically from infective larvae to young adults and then decreased in adult worms, with the male worms exhibiting significantly higher levels of expression than female worms. These findings provide information related to the regulation of gene expression during the growth, development and pathogenesis of young adults of A. cantonensis. PMID:24037191

  19. Treatment with mebendazole is not associated with distal migration of adult Angiostrongylus costaricensis in the murine experimental infection.

    PubMed

    Mentz, Márcia Bohrer; Graeff-Teixeira, Carlos; Garrido, Cinara Tentardini

    2004-01-01

    Abdominal angiostrongyliasis is a zoonotic infection produced by a metastrongylid intra-arterial nematode, Angiostrongylus costaricensis. Human accidental infection may result in abdominal lesions and treatment with anti-helminthics is contra-indicated because of potential higher morbidity with excitement or death of worms inside vessels. To evaluate the effect of mebendazole on localization of the worms, male Swiss mice, 5 week-old, were infected with 10 third stage larvae per animal. Twelve infected mice were treated with oral mebendazol, at 5 mg/kg/day, for 5 consecutive days, begining 22 days after inoculation. As control groups, 12 infected but non-treated mice and other 12 non-infected and non-treated mice were studied. The findings at necropsy were, respectively for the treated (T) and control (C) groups: 92% and 80% of the worms were inside the cecal mesenteric arterial branch; 8% and 10% were located inside the aorta. Only in the group C some worms (10%) were found inside the portal vein or splenic artery. These data indicate that treatment with mebendazole does not lead to distal or ectopic migration of A. costaricensis worms. PMID:15141273

  20. Control measures for slug and snail hosts of Angiostrongylus cantonensis, with special reference to the semi-slug Parmarion martensi.

    PubMed

    Hollingsworth, Robert G; Howe, Kathleen; Jarvi, Susan I

    2013-06-01

    Slugs and snails (class Gastropoda) are the obligate intermediate hosts of the rat lungworm, Angiostrongylus cantonensis. This nematode is the causative agent of human angiostrongyliasis and the most common cause of human eosinophilic meningoencephalitis. Humans can become infected by accidental consumption of slugs or snails and possibly flatworms (or a portion of one of these animals) in fresh produce, but the slime from these animals can contain nematodes and may also constitute a disease risk. Gastropod carriers in Hawa'i include, among other species, giant African snails, veronicellid slugs, and the semi-slug Parmarion martensi. This latter species was first discovered on the island of Hawa'i in 2004 and is now common in the area where the majority of the state's documented cases of human angiostrongyliasis occurred between 2005 and 2011. This species is considered a high risk carrier of A. cantonensis because of its climbing behavior, abundance around human dwellings, and high worm burdens. One individual collected from east Hawa'i Island contained >6,800 infective third stage A. cantonensis larvae. Common and efficient control methods for slugs and snails include sanitation (eg, removal of objects that serve as hiding places) and the use of poison food baits, such as those containing metaldehyde and iron. An iron-containing bait that is relatively safe to non-target organisms was effective in controlling semi-slugs in cage experiments, although it killed more slowly than a metaldehyde-containing bait and the majority of slugs affected did not die until 1-2 weeks following ingestion. PMID:23901389

  1. Phylogenetic relationship of the Brazilian isolates of the rat lungworm Angiostrongylus cantonensis (Nematoda: Metastrongylidae) employing mitochondrial COI gene sequence data

    PubMed Central

    2012-01-01

    Background The rat lungworm Angiostrongylus cantonensis can cause eosinophilic meningoencephalitis in humans. This nematode’s main definitive hosts are rodents and its intermediate hosts are snails. This parasite was first described in China and currently is dispersed across several Pacific islands, Asia, Australia, Africa, some Caribbean islands and most recently in the Americas. Here, we report the genetic variability among A. cantonensis isolates from different geographical locations in Brazil using mitochondrial cytochrome c oxidase subunit I (COI) gene sequences. Methods The isolates of A. cantonensis were obtained from distinct geographical locations of Brazil. Genomic DNAs were extracted, amplified by polymerase reaction, purified and sequenced. A partial sequence of COI gene was determined to assess their phylogenetic relationship. Results The sequences of A. cantonensis were monophyletic. We identified a distinct clade that included all isolates of A. cantonensis from Brazil and Asia based on eight distinct haplotypes (ac1, ac2, ac3, ac4, ac5, ac6, ac7 and ac8) from a previous study. Interestingly, the Brazilian haplotype ac5 is clustered with isolates from Japan, and the Brazilian haplotype ac8 from Rio de Janeiro, São Paulo, Pará and Pernambuco states formed a distinct clade. There is a divergent Brazilian haplotype, which we named ac9, closely related to Chinese haplotype ac6 and Japanese haplotype ac7. Conclusion The genetic variation observed among Brazilian isolates supports the hypothesis that the appearance of A. cantonensis in Brazil is likely a result of multiple introductions of parasite-carrying rats, transported on ships due to active commerce with Africa and Asia during the European colonization period. The rapid spread of the intermediate host, Achatina fulica, also seems to have contributed to the dispersion of this parasite and the infection of the definitive host in different Brazilian regions. PMID:23130987

  2. Angiostrongylus vasorum: Experimental Infection and Larval Development in Omalonyx matheroni

    PubMed Central

    Mozzer, L. R.; Montresor, L. C.; Vidigal, T. H. D. A.; Lima, W. S.

    2011-01-01

    The susceptibility and suitability of Omalonyx matheroni as an intermediate host of Angiostrongylus vasorum and the characteristics of larval recovery and development were investigated. Mollusks were infected, and from the 3rd to the 25th day after infection, larvae were recovered from groups of 50 individuals. The first observation of L2 was on the 5th day, and the first observation of L3 was on the 10th day. From the 22nd day on, all larvae were at the L3 stadium. Larval recovery varied from 78.2% to 95.2%. We found larval development to be faster in O. matheroni than in Biomphalaria glabrata. Our findings indicate that this mollusk is highly susceptible to A. vasorum. Infective L3 were orally inoculated into a dog, and the prepatent period was 39 days. This is the first study to focus on O. matheroni as an intermediate host of A. vasorum. PMID:21687642

  3. Pathological findings of Angiostrongylus vasorum infection in red foxes (Vulpes vulpes) from Central Italy, with the first report of a disseminated infection in this host species.

    PubMed

    Eleni, Claudia; Grifoni, Goffredo; Di Egidio, Alessandra; Meoli, Roberta; De Liberato, Claudio

    2014-03-01

    In Europe, the red fox (Vulpes vulpes) is considered the reservoir of Angiostrongylus vasorum, nematode residing in the pulmonary arteries and right heart of dogs and many species of wild carnivores. Italy is considered one of the European countries where this nematode is actually spreading. Between May 2007 and November 2013, 62 foxes found dead in Central Italy were necropsied. Right heart and pulmonary arteries were opened and checked for the presence of adult parasites. Impression smears from sectioned lungs were examined for the presence of first-stage larvae, and samples of lungs were processed for histological examination. In order to detect eventual disseminated infections, samples of heart, pulmonary lymph nodes, liver, kidneys, and brain of foxes positive for A. vasorum at necropsy or lungs histological examination were processed for histological examination. An overall prevalence of 43.5% was recorded. Light, mild, and severe lung lesions were detected in 33.3, 22.2, and 25.9% of infected animals, respectively. Severe lesions were more frequent in animals younger than 12 months. In five infected foxes (18.5%), no gross lesions were observed, while for three animals, angiostrongylosis was considered the cause of death. A case of disseminated angiostrongylosis was detected and another one was suspected. This is the firs report of disseminated angiostrongylosis in the fox. PMID:24532011

  4. Fatal Canid herpesvirus 1 infection in an adult dog.

    PubMed

    Gadsden, Barbie J; Maes, Roger K; Wise, Annabel G; Kiupel, Matti; Langohr, Ingeborg M

    2012-05-01

    Canid herpesvirus 1 (CaHV-1) is a well-known cause of fatal hepatic and renal necrosis in neonatal puppies. In adult dogs infected with CaHV-1, papulovesicular genital lesions may be observed. CaHV-1 infection during pregnancy can lead to embryonic resorption, abortion, and stillbirth. In high-density dog populations, CaHV-1 can also contribute to kennel cough. Furthermore, recent literature has clearly documented that CaHV-1 can induce ocular disease in immature and adult dogs. The current study describes a case of fatal CaHV-1 infection in a 9-year-old spayed female Bichon Frise dog. Following a history of vomiting and diarrhea, the dog deteriorated and subsequently died. The main lesions were multifocal areas of necrosis with intranuclear inclusion bodies in the liver, adrenal gland, and small intestine, similar to the lesions observed in CaHV-1-infected puppies. Infection with CaHV-1 was confirmed on samples of liver by polymerase chain reaction, immunohistochemistry, and in situ hybridization. There was no indication of immunosuppression in this dog. Based on the results presented herein, CaHV-1 should be included in the list of differential diagnoses of hepatic necrosis in adult dogs. PMID:22529135

  5. Fleas infesting pets in the era of emerging extra-intestinal nematodes

    PubMed Central

    2013-01-01

    Modifications in climatic conditions, movements of hosts and goods, changes in animal phenology and human behaviour and increase of wildlife, are presently concurring in the geographic spread of vectors and cardio-respiratory nematodes, e.g. Dirofilaria immitis, Angiostrongylus vasorum, Aelurostrongylus abstrusus and Capillaria aerophila. All these factors may also influence dispersion and clinical significance of fleas, thus posing relevant challenges in those regions where other parasites are emerging at the same time. Ctenocephalides felis, Ctenocephalides canis and Pulex irritans cause discomfort, nuisance, allergic reactions, anaemia, and may transmit several pathogens, some of them are of importance for public health. The present article reviews the importance of fleas in small animal practice and their sanitary relevance for dogs, cats and humans, and discusses current control methods in the present era of emerging extra-intestinal nematodes, towards a possible changing perspective for controlling key parasites affecting companion animals. PMID:23497511

  6. An investigation of palaeodietary variability in European Pleistocene canids

    NASA Astrophysics Data System (ADS)

    Flower, Lucy O. H.; Schreve, Danielle C.

    2014-07-01

    Temporal and interspecific dietary variability were investigated in three canid taxa, Canis lupus, Canis mosbachensis and Canis etruscus, across a range of British and mainland European wolf assemblages from the Early Pleistocene to Recent periods. Using established cranio-dental indicators to reveal dietary specialisations towards bone eating, flesh slicing, and non-flesh food crushing, inferences were made concerning the proportions of flesh to non-flesh foods in the diet, and hence the level of carnivory adopted by each taxon. Significant temporal differences were found in the diet and frequency of tooth wear of C. lupus from MIS 3, 5a and 7 in Britain. Relative body size comparisons based on lower carnassial length also revealed variation in body size for the Pleistocene age groups, correlating with differences in diet. Stepwise Discriminant Function Analyses revealed large-bodied MIS 5a C. lupus to be hypercarnivorous and specialised in fast flesh slicing and to some extent bone consumption, whereas relatively smaller-bodied MIS 3 and 7 C. lupus were both less carnivorous and more specialised in crushing non-meat foods. Modern wolves from central Sweden are smaller than those of MIS 5a and hypercarnivorous, although with greater specialisation towards crushing of non-meat foods. Temporal variations in diet were related to changes in prey diversity, competition from other carnivores, openness of the environment, and ultimately climate, and reflect the cranio-dental plasticity of C. lupus. In contrast, no temporal differences in diet were found in age groups of C. mosbachensis and C. etruscus, which may relate to more stable overall conditions in comparison to the later Pleistocene. The cranio-dental characteristics of the smaller-bodied mesocarnivore C. etruscus indicate adaptations to non-meat food crushing, whereas in the similarly small C. mosbachensis, enhanced flesh slicing capabilities and reduced crushing abilities indicate that it was more carnivorous than C. etruscus. C. etruscus and C. mosbachensis were both more specialised than C. lupus.

  7. The finding of Angiostrongylus cantonensis in rats in New Orleans.

    PubMed

    Campbell, B G; Little, M D

    1988-05-01

    Twenty of 94 (21.4%) Rattus norvegicus trapped in New Orleans, Louisiana, between April 1986 and February 1987 were infected with Angiostrongylus cantonensis (3-62 worms per rat). This is the first report of the parasite from North America. A carnivorous snail, Euglandina rosea, was found experimentally to be able to serve as both an intermediate and a paratenic host. Other locally occurring gastropods that were successfully infected experimentally included Mesodon thyroidus, Anguispira alternata, Bradybaena similaris, Subulina octona, Polygyra triodontoides, Vaginulus ameghini, Philomycus carolinianus, Deroceras laeve, Limax flavus, and Lehmannia poirieri. Laboratory reared, 4- to 5-week-old M. thyroidus and D. laeve were able to support the development of small numbers of larvae to the third stage. First stage larvae of A. cantonensis in the feces of experimentally infected rats were found not to migrate out of the fecal pellet; this behavior favors the infection of feces-consuming gastropods. Twenty heavily infected L. flavus were observed over a period of 2 months, and shedding of third stage larvae of A. cantonensis was never seen. While factors support the spread of A. cantonensis in rats in the southern United States, the probability of human infection is uncertain since the parasite is transmitted primarily by ingestion of raw intermediate and paratenic hosts. PMID:3275136

  8. Human parasitic meningitis caused by Angiostrongylus cantonensis infection in Taiwan.

    PubMed

    Tsai, Hung-Chin; Chen, Yao-Shen; Yen, Chuan-Min

    2013-06-01

    The major cause of eosinophilic meningitis in Taiwan is Angiostrongylus cantonensis. Humans are infected by ingesting terrestrial and freshwater snails and slugs. In 1998 and 1999, two outbreaks of eosinophilic meningitis caused by A. cantonensis infection were reported among 17 adult male immigrant Thai laborers who had eaten raw golden apple snails (Pomacea canaliculata). Another outbreak associated with consuming a health drink consisting of raw vegetable juice was reported in 2001. These adult cases differed from reports in the 1970s and 1980s, in which most of the cases were in children. With improvements in public health and education of foreign laborers, there have since been only sporadic cases in Taiwan. Review of clinical research indicates inconsistent association of Magnetic Resonance Imaging (MRI) results with clinical features of eosinophilic meningitis. MRI features were nonspecific but there was an association between the presence of high brain MRI signal intensities and severity of peripheral and cerebrospinal fluid (CSF) eosinophilia. Inflammatory markers have been identified in the CSF of patients with eosinophilic meningitis caused by A. cantonensis infection, and vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and the matrix metalloproteinase system may be associated with blood-brain barrier disruption. Eosinophilic meningitis caused by A. cantonensis infection is not a reportable disease in Taiwan. It is important that a public advisory and education program be developed to reduce future accidental infection. PMID:23901378

  9. Human Parasitic Meningitis Caused by Angiostrongylus cantonensis Infection in Taiwan

    PubMed Central

    Chen, Yao-Shen; Yen, Chuan-Min

    2013-01-01

    The major cause of eosinophilic meningitis in Taiwan is Angiostrongylus cantonensis. Humans are infected by ingesting terrestrial and freshwater snails and slugs. In 1998 and 1999, two outbreaks of eosinophilic meningitis caused by A. cantonensis infection were reported among 17 adult male immigrant Thai laborers who had eaten raw golden apple snails (Pomacea canaliculata). Another outbreak associated with consuming a health drink consisting of raw vegetable juice was reported in 2001. These adult cases differed from reports in the 1970s and 1980s, in which most of the cases were in children. With improvements in public health and education of foreign laborers, there have since been only sporadic cases in Taiwan. Review of clinical research indicates inconsistent association of Magnetic Resonance Imaging (MRI) results with clinical features of eosinophilic meningitis. MRI features were nonspecific but there was an association between the presence of high brain MRI signal intensities and severity of peripheral and cerebrospinal fluid (CSF) eosinophilia. Inflammatory markers have been identified in the CSF of patients with eosinophlic meningitis caused by A. cantonensis infection, and vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and the matrix metalloproteinase system may be associated with blood-brain barrier disruption. Eosinophilic meningitis caused by A. cantonensis infection is not a reportable disease in Taiwan. It is important that a public advisory and education program be developed to reduce future accidental infection. PMID:23901378

  10. Cross-reactions of sera from dogs infected with Angiostrongylus vasorum in commercially available Dirofilaria immitis test kits

    PubMed Central

    2012-01-01

    Background Dirofilaria immitis and Angiostrongylus vasorum are both important potentially fatal canine nematodes with overlapping endemic areas, especially in Europe. The preadult and adult stages of both species are living in the Arteria pulmonalis and the right heart, and diagnostically detectable circulating parasite antigens have been demonstrated for both species. For the detection of D. immitis infections, a variety of commercial tests have been developed, however, they have not been evaluated for cross-reactions against circulating antigens of A. vasorum. Methods In this study, potential cross-reactions of sera from 16 dogs, which were experimentally infected with A. vasorum and which had circulating antigens as confirmed by a species-specific ELISA, were evaluated for the detection of A. vasorum antigen in six commercially available D. immitis test kits. Results In three fast tests (Witness® Dirofilaria, SensPERT® Canine Heartworm, SNAP® 4Dx® Plus), all sera were negative. One fast membrane ELISA (SNAP® HTWM RT Test) was positive with four sera (25%), and one serum delivered a non-valid result twice. In the PetChek® HTWM PF Test, depending on the interpretation protocol, 5 or 8 dogs (31.2 – 50%) were positive. With the DiroCHEK®-ELISA, a single A. vasorum-infected dog (6.2%) tested positive. Conclusions Due to potential cross-reactions with A. vasorum in commercially available test kits for the detection of D. immitis antigen, the simultaneous use of highly specific diagnostic methods for the differentiation of these two canine heart worms is recommended. PMID:23148786

  11. The effect of some biological and physical factors on infection of Biomphalaria glabrata with Angiostrongylus cantonensis

    Microsoft Academic Search

    Fouad Yousif; Georg Lämmler

    1975-01-01

    Several biological and physical factors which may influence infection of Biomphalaria glabrata snails with the first stage larvae of Angiostrongylus cantonensis were studied. These factors were: the size of snails, the number of first stage larvae to which snails were exposed, the age of larvae, individual exposure compared with mass exposure of snails, the length of exposure period and the

  12. Ecomorphological study of large canids from the lower Pleistocene of southeastern Spain

    Microsoft Academic Search

    PAUL PALMQVIST; ALFONSO ARRIBAS; BIENVENIDO MARTÍNEZ-NAVARRO

    2007-01-01

    An ecomorphological analysis of the skeletal remains of large canids, Canis ( Xenocyon ) falconeri and Canis etruscus (Mammalia, Carnivora, Canidae), preserved in an assemblage of large mam- mals from the lower Pleistocene site at Venta Micena (Guadix-Baza Basin, Orce, Granada, southeastern Spain) is reported. Mean body mass of adult individuals was estimated to be around 10 kg for C.

  13. Hunting behaviour of a sympatric felid and canid in relation to vegetative cover

    Microsoft Academic Search

    Dennis L. Murray; Stan Boutin; Mark O'Donoghue; Vilis O. Nams

    1995-01-01

    Carnivore foraging behaviour is suited for hunting in specific vegetative cover types and therefore is largely stereotypical within taxonomic families. Felids typically employ dense cover to stalk or ambush prey, whereas canids do not make use of vegetation when hunting. Sympatric lynx, Lynx canadensis, and coyotes, Canis latrans, were tracked in snow for three winters and hunting behaviour in relation

  14. Social communication in canids: evidence for the evolution of a stereotyped Mammalian display.

    PubMed

    Bekoff, M

    1977-09-01

    The variability in the duration and form of the canid play bow was studied in infant coyotes, wolves, wolf-dog hybrids, beagles, and adult free-ranging dogs. Both duration and form showed marked stereotypy. It appears that the role of this context-specific social signal in the communication of play intention has been fostered by selection for "morphological" stereotypy. PMID:17836077

  15. Social Communication in Canids: Evidence for the Evolution of a Stereotyped Mammalian Display

    Microsoft Academic Search

    Marc Bekoff

    1977-01-01

    The variability in the duration and form of the canid play bow was studied in infant coyotes, wolves, wolf-dog hybrids, beagles, and adult free-ranging dogs. Both duration and form showed marked stereotypy. It appears that the role of this context-specific social signal in the communication of play intention has been fostered by selection for \\

  16. Efficacy of tribendimidine against Angiostrongylus cantonensis infection in the mice.

    PubMed

    Wang, Juan; Wei, Jie; Zeng, Xin; Liang, Jin-Yi; Wu, Feng; Li, Zheng-Yu; Zheng, Huan-Qin; He, Han-Jiang; Wu, Zhong-Dao

    2013-03-01

    Angiostrongyliasis, also known as eosinophils meningitis, is caused by Angiostrongylus cantonensis parasites in the human central nervous system. Currently, the drug of choice for treatment of angiostrongyliasis is albendazole, but dead worm lysis causes severe inflammatory response, which leads to central nervous system damage. Tribendimidine, a broad-spectrum anti-helmintic drug developed in China, is a derivative of amidantel. This study was designed to test the efficacy of tribendimidine against A. cantonensis in mice. We treated 65 infected female BALB/c mice with tribendimidine or albendazole by oral route. We observed that tribendimidine at doses of 50, 100 and 200 mg/kg/day was effective, and the worm reduction rates were 54.8 %,77.4 %, and 100 % compared with the control group. In addition, the therapeutic effect of early tribendimidine treatment (7 days post-infection [PI]) was better than the late treatment (14 days PI), in comparison with the albendazole group (20 mg/kg/day). The index of therapeutic efficacy included body weight, neurological function, survival time, worm reduction, mRNA levels of proinflammatory cytokines in brain tissue, histopathological examination and electron microscopy scanning. The results showed that tribendimidine could kill the larvae of A. cantonensis in the mice model, and the worm's body wall was observed to be damaged. After treatment with tribendimidine, the survival conditions such as body weight and neurological function were improved, and brain inflammation was reduced in infected mice. This study showed a strong efficacy of tribendimidine against A. cantonensis and provided suitable alternative treatments to further explore its potential use in treatment of human angiostrongyliasis. PMID:23377146

  17. Preliminary molecular characterization of the human pathogen Angiostrongylus cantonensis

    PubMed Central

    He, Hualiang; Cheng, Mei; Yang, Xiao; Meng, Jinxiu; He, Ai; Zheng, Xiaoying; Li, Zhuoya; Guo, Pengjuan; Pan, Zhihua; Zhan, Ximei

    2009-01-01

    Background Human angiostrongyliasis is an emerging food-borne public health problem, with the number of cases increasing worldwide, especially in mainland China. Angiostrongylus cantonensis is the causative agent of this severe disease. However, little is known about the genetics and basic biology of A. cantonensis. Results A cDNA library of A. cantonensis fourth-stage larvae was constructed, and ~1,200 clones were sequenced. Bioinformatic analyses revealed 378 cDNA clusters, 54.2% of which matched known genes at a cutoff expectation value of 10-20. Of these 378 unique cDNAs, 168 contained open reading frames encoding proteins containing an average of 238 amino acids. Characterization of the functions of these encoded proteins by Gene Ontology analysis showed enrichment in proteins with binding and catalytic activity. The observed pattern of enzymes involved in protein metabolism, lipid metabolism and glycolysis may reflect the central nervous system habitat of this pathogen. Four proteins were tested for their immunogenicity using enzyme-linked immunosorbent assays and histopathological examinations. The specificity of each of the four proteins was superior to that of crude somatic and excretory/secretory antigens of larvae, although their sensitivity was relatively low. We further showed that mice immunized with recombinant cystatin, a product of one of the four cDNA candidate genes, were partially protected from A. cantonensis infection. Conclusion The data presented here substantially expand the available genetic information about the human pathogen A. cantonensis, and should be a significant resource for angiostrongyliasis researchers. As such, this work serves as a starting point for molecular approaches for diagnosing and controlling human angiostrongyliasis. PMID:19852860

  18. Plant–nematode interactions

    Microsoft Academic Search

    Valerie M Williamson; Cynthia A Gleason

    2003-01-01

    Root-knot nematodes and cyst nematodes are obligate, biotrophic pathogens of numerous plant species. These organisms cause dramatic changes in the morphology and physiology of their hosts. The molecular characterization of induced plant genes has provided insight into the plant processes that are usurped by nematodes as they establish their specialized feeding cells. Recently, several gene products have been identified that

  19. How nematode sperm crawl

    Microsoft Academic Search

    Dean Bottino; Alexander Mogilner; Tom Roberts; Murray Stewart; George Oster

    Sperm of the nematode, Ascaris suum, crawl using lamellipodial protrusion, adhesion and retraction, a process analogous to the amoeboid motility of other eukaryotic cells. However, rather than employing an actin cytoskeleton to generate locomotion, nematode sperm use the major sperm protein (MSP). Moreover, nematode sperm lack detectable molecular motors or the battery of actin-binding proteins that characterize actin-based motility. The

  20. Effects of infection by larvae of Angiostrongylus cantonensis (Nematoda, Metastrongylidae) on the lipid metabolism of the experimental intermediate host Biomphalaria glabrata (Mollusca: Gastropoda).

    PubMed

    Tunholi-Alves, Vinícius Menezes; Tunholi, Victor Menezes; Gôlo, Patrícia; Lima, Mariana; Garcia, Juberlan; Júnior, Arnaldo Maldonado; Pontes, Emerson Guedes; Bittencourt, Vânia Rita Elias Pinheiro; Pinheiro, Jairo

    2013-05-01

    Experimental infection of Biomphalaria glabrata by Angiostrongylus cantonensis induces significant changes in the concentrations of triacylglycerol and cholesterol in the hemolymph and of neutral lipids in the digestive gonad-gland (DGG) complex of the host snail. In this study, snails were dissected after 1, 2, and 3 weeks of infection to collect the hemolymph and DGG and to measure the levels of cholesterol and triacylglycerol in the hemolymph and neutral lipid fractions in the tissues. The results show that infection by this nematode resulted in a significant decrease in the concentrations of both cholesterol and triacylglycerol in the hemolymph of B. glabrata during the parasite's initial ontogenic development period. This reduction indicates the possible use of these molecules by both parasite and host not only as energy substrates but also as structural factors required during development of the parasite's larval stages. In parallel, changes in the neutral lipid profile in the DGG and lipase activity of the infected snails were observed, indicating the importance of these molecules for successful infection. PMID:23377121

  1. Extraintestinal nematodes of the red fox Vulpes vulpes in north-west Italy.

    PubMed

    Magi, M; Guardone, L; Prati, M C; Mignone, W; Macchioni, F

    2015-07-01

    Extraintestinal nematodes of the red fox (Vulpes vulpes) are a wide group of parasites that infect wild and domestic carnivores and occasionally humans. Nematodes in the cardiopulmonary system, stomach, urinary apparatus and muscle tissue of 165 red foxes (Vulpes vulpes) from north-west Italy (Liguria and Piedmont) were investigated between 2009 and 2012. Of the cardiopulmonary nematodes, a high prevalence of Angiostrongylus vasorum and Eucoleus aerophilus (syn. Capillaria aerophila) was found, 78.2% and 41.8% respectively; Crenosoma vulpis (15.8%) and Filaroides spp. (4.8%) were also found. Spirocerca lupi (23.5%), Aonchotheca putorii (syn. Capillaria putorii) (8.6%) and Physaloptera spp. (2.5%) were detected in the stomach and Pearsonema plica (syn. Capillaria plica) (56.8%) in the bladder. Eucoleus boehmi (syn. Capillaria boehmi) was also detected in the nasal cavities of one of the two foxes examined. A coprological examination revealed eggs of E. aerophilus, A. putorii, S. lupi, Physaloptera spp. and eggs of intestinal parasites. Filarial worms were absent in all the 165 animals examined, nor was there evidence of Trichinella spp. in any of the foxes. The foxes were found to host a high prevalence of many species of extraintestinal nematodes. The prevalence of A. vasorum in foxes found in the present study is among the highest in Europe. In addition, to the best of our knowledge, E. boehmi and Filaroides spp. have never been reported before in this host in Italy. PMID:24725462

  2. Experimental examination of behavioural interactions between free-ranging wild and domestic canids

    Microsoft Academic Search

    Abi Tamim Vanak; Maria Thaker; Matthew E. Gompper

    2009-01-01

    The structure of mammalian carnivore communities is strongly influenced by both intraguild competition and predation. However,\\u000a intraguild interactions involving the world’s most common carnivore, the domestic dog (Canis familiaris), have rarely been investigated. We experimentally examined the behavioural responses of a small canid, the Indian fox (Vulpes bengalensis), to the presence of dogs and dog odours. Resource competition between dogs

  3. Lack of evidence of paratuberculosis in wild canids from Southwestern Europe

    Microsoft Academic Search

    Raquel Sobrino; O. Aurtenetxe; Tania Carta; L. Mamian; X. Gerrikagoitia; A. Balseiro; A. Oleaga; I. A. Sevilla; M. Barral; J. M. Garrido; Christian Gortazar

    2011-01-01

    Wild carnivores are at the top of the trophic chain. They are predators and carrion consumers, and thus, prone to come in\\u000a contact with disease agents contaminating the environment or infecting live or dead animals. We hypothesized that wild canids\\u000a could be used as sentinels for the detection of regions with higher Mycobacterium avium paratuberculosis (MAP) prevalence in wild and

  4. Naturally occurring and melengestrol acetate-associated reproductive tract lesions in zoo canids.

    PubMed

    Moresco, A; Munson, L; Gardner, I A

    2009-11-01

    As husbandry practices have improved, safe and effective contraception for captive wildlife management has become a necessity. Melengestrol acetate (MGA), a synthetic progestin, is highly effective and has been used in many zoo species. Long-term use of MGA has been associated with uterine lesions in zoo felids, but effects in zoo canids have not been evaluated. This retrospective study documented spontaneously occurring lesions and investigated the impact of MGA on the reproductive health of zoo canids. Reproductive tracts from adult females were submitted by US zoos to the Association of Zoos & Aquariums' Wildlife Contraception Center Health Surveillance Program. Reproductive tracts were sampled and processed for histopathologic examination following standard protocols. Microscopic evaluations were performed without prior knowledge of MGA treatment status. Prevalence of uterine lesions was evaluated and compared between MGA-treated animals (n = 20) and control (untreated) animals (n = 61). Common lesions within the study population as a whole included endometrial hyperplasia (predominantly cystic) (53%), hydrometra (33%), and adenomyosis (25%). Treatment with MGA was a risk factor for endometrial hyperplasia, hydrometra, fibrosis, and adenomyosis. Uterine mineralization occurred exclusively in MGA-treated animals. Results indicate that MGA contraception can lead to lesions that may permanently impair the fertility of females. Therefore, if long-term contraception of zoo canids is necessary, the use of alternate methods of reproductive control such as gonadotropin-releasing hormone (GnRH) analogs or GnRH vaccines that reduce gonadal hormone exposure should be pursued. PMID:19605907

  5. Comparative genomics of 3 farm canids in relation to the dog.

    PubMed

    Switonski, M; Szczerbal, I; Nowacka-Woszuk, J

    2009-01-01

    There are 3 canids besides the dog (Canis familiaris): the red fox (Vulpes vulpes), arctic fox (Alopex lagopus) and Chinese raccoon dog (Nyctereutes procyonoides procyonoides), which have been extensively studied with the use of cytogenetic and molecular genetics techniques. These 3 species are considered as farm fur-bearing animals. In addition, they are also useful models in comparative genomic studies of the canids. In this review genome organization, karyotype evolution, comparative marker maps, DNA polymorphism and similarity of selected gene sequences of the 3 farm species are discussed in relation to the dog. Also the nature and variability of the B chromosomes, present in the red fox and the Chinese raccoon dog, were considered. These comparative analyses showed that among the studied canids the Chinese raccoon dog is phylogenetically the closest species to the dog. On the other hand, the most advanced linkage and cytogenetic marker maps of the red fox genome facilitate genome scanning studies with the aim to search for chromosome locations of QTL regions for behavior and production traits. PMID:20016159

  6. The role of clade competition in the diversification of North American canids.

    PubMed

    Silvestro, Daniele; Antonelli, Alexandre; Salamin, Nicolas; Quental, Tiago B

    2015-07-14

    The history of biodiversity is characterized by a continual replacement of branches in the tree of life. The rise and demise of these branches (clades) are ultimately determined by changes in speciation and extinction rates, often interpreted as a response to varying abiotic and biotic factors. However, understanding the relative importance of these factors remains a major challenge in evolutionary biology. Here we analyze the rich North American fossil record of the dog family Canidae and of other carnivores to tease apart the roles of competition, body size evolution, and climate change on the sequential replacement of three canid subfamilies (two of which have gone extinct). We develop a novel Bayesian analytic framework to show that competition from multiple carnivore clades successively drove the demise and replacement of the two extinct canid subfamilies by increasing their extinction rates and suppressing their speciation. Competitive effects have likely come from ecologically similar species from both canid and felid clades. These results imply that competition among entire clades, generally considered a rare process, can play a more substantial role than climate change and body size evolution in determining the sequential rise and decline of clades. PMID:26124128

  7. ES proteins analysis of Angiostrongylus cantonensis : products of the potential parasitism genes?

    Microsoft Academic Search

    Wenzhen Fang; Shisan Xu; Yinan Wang; Fang Ni; Shaolei Zhang; Jiang Liu; Xiaobin Chen; Damin Luo

    2010-01-01

    The expressed sequence tags (ESTs) of Angiostrongylus cantonensis were analyzed in an attempt to gain further insight into its genomic expression patterns. A total of 1,277 ESTs of A. cantonensis were randomly downloaded from NCBI databank. ESTs were analyzed and annotated using Blastx. The result showed that there\\u000a were 60 ESTs had no match to any of the proteins and

  8. Brain and spinal cord haemorrhages associated with Angiostrongylus vasorum infection in four dogs

    Microsoft Academic Search

    A. Wessmann; D. Lu; C. R. Lamb; B. Smyth; P. Mantis; K. Chandler; A. Boag; G. B. Cherubini; R. Cappello

    2006-01-01

    Multifocal haemorrhages associated with Angiostrongylus vasorum infection were observed in the central nervous system of four dogs with neurological signs including depression, seizures, spinal pain and paresis. In magnetic resonance images the majority of the lesions were isointense or slightly hyperintense in T1-weighted images, hyperintense in T2-weighted images and hypointense in T2*-weighted (gradient echo) images, compatible with haemorrhages more than

  9. The common frog ( Rana temporaria ) as a potential paratenic and intermediate host for Angiostrongylus vasorum

    Microsoft Academic Search

    G. Bolt; J. Monrad; F. Frandsen; P. Henriksen; H. H. Dietz

    1993-01-01

    Common frogs (Rana temporaria) were exposed either to third-stage larvae (L3) or to first-stage larvae (L1) ofAngiostrongylus vasorum. Following exposure to L3, viable larvae could be detected in the frogs for at least 2 weeks. Following exposure to L1, the frogs developed viable L3 in their tissues within 30 days. In a test of the infectivity of these larvae, one

  10. Application technology for entomopathogenic nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diverse technology is available for the application of entomopathogenic nematodes. Application usually consists of nematode distribution via aqueous suspension in various irrigation systems and spray equipment. The choice of application equipment, and method in which the nematodes are applied, can...

  11. Cyst Nematodes and Syncytia

    Microsoft Academic Search

    Miroslaw Sobczak; Wladyslaw Golinowski

    \\u000a Plant-parasitic nematodes from the genera Heterodera and Globodera change the morphogenetic programme of plant root cells and induce development of a specific feeding site called a syncytium.\\u000a The syncytium is the only source of nutrients for developing parasites and functions only for the nematode’s benefit. Its\\u000a development begins from a single cell selected by the infective second stage juvenile. The

  12. Nematodes in Texas Golf Courses

    E-print Network

    Crow, William T.

    2000-04-10

    construction require 90 percent sand content in the root zone mixture, an ideal habitat for the sting nematode. Awl nematodes (Dolichodorus ssp.):Awl nematodes are rare in Texas, but are as damaging as sting nematodes. Awl nematodes are usually found only... in moist soil near ponds or ditches, and are ectoparasitic. Lance nematodes (Hoplolaimus ssp.): Lance nematodes also can be very damaging to turf grasses. They are more common in Texas than sting nematodes, and are more common in soils with a higher silt...

  13. Assessment of the combination of spinosad and milbemycin oxime in preventing the development of canine Angiostrongylus vasorum infections.

    PubMed

    Böhm, Claudia; Schnyder, Manuela; Thamsborg, Stig Milan; Thompson, Caryn M; Trout, Candace; Wolken, Sonja; Schnitzler, Beate

    2014-01-31

    Angiostrongylus vasorum is an increasingly reported parasite in Europe that develops in dogs after ingestion of infective third stage larvae (L3) that reside in gastropod molluscs which are needed to complete the parasite's life-cycle. Infection can produce a diversity of clinical signs, determined by involvement of the respiratory, neurological, and/or coagulation system, with a likely fatal outcome in the absence of treatment. Few drugs have been shown to reliably prevent infection, and data on treatment of infections is limited. A controlled, randomized, partially blinded laboratory study was therefore executed to evaluate the efficacy and safety of a combination tablet of spinosad/milbemycin oxime in dogs inoculated with approximately 250 A. vasorum L3. Sixteen healthy nematode free adult dogs were randomly allocated to two study groups of 8 dogs each. Thirty days post inoculation (dpi) all dogs in the fed state were treated: dogs in group B were treated with spinosad and milbemycin oxime at the dose rates of 45-60 mg/kg and 0.75-1.0mg/kg bodyweight, respectively, approximately the lower half portion of the expected full unit dose range; dogs in group A were treated with placebo tablets. All dogs were euthanized and necropsied 56-58 dpi. The heart and lungs were examined to determine the presence of A. vasorum. All placebo group dogs were infected at necropsy with counts ranging from 22 to 98 adult worms and a geometric mean worm count of 55.2. In contrast, the geometric mean worm count in the spinosad/milbemycin oxime group was 0.7 with worm numbers ranging from 0 to 8. The results of this study demonstrate that a single treatment with the tablet combination of spinosad and milbemycin oxime administered 30 dpi provided 98.8% preventive efficacy against development of adult A. vasorum infections. Monthly treatments with spinosad and milbemycin oxime have the potential to prevent the establishment of infections with A. vasorum in dogs. PMID:24269160

  14. Ancient DNA Analysis of the Oldest Canid Species from the Siberian Arctic and Genetic Contribution to the Domestic Dog

    PubMed Central

    Lee, Esther J.; Merriwether, D. Andrew; Kasparov, Alexei K.; Nikolskiy, Pavel A.; Sotnikova, Marina V.; Pavlova, Elena Yu; Pitulko, Vladimir V.

    2015-01-01

    Modern Arctic Siberia provides a wealth of resources for archaeological, geological, and paleontological research to investigate the population dynamics of faunal communities from the Pleistocene, particularly as the faunal material coming from permafrost has proven suitable for genetic studies. In order to examine the history of the Canid species in the Siberian Arctic, we carried out genetic analysis of fourteen canid remains from various sites, including the well-documented Upper Paleolithic Yana RHS and Early Holocene Zhokhov Island sites. Estimated age of samples range from as recent as 1,700 years before present (YBP) to at least 360,000 YBP for the remains of the extinct wolf, Canis cf. variabilis. In order to examine the genetic affinities of ancient Siberian canids species to the domestic dog and modern wolves, we obtained mitochondrial DNA control region sequences and compared them to published ancient and modern canid sequences. The older canid specimens illustrate affinities with pre-domestic dog/wolf lineages while others appear in the major phylogenetic clades of domestic dogs. Our results suggest a European origin of domestic dog may not be conclusive and illustrates an emerging complexity of genetic contribution of regional wolf breeds to the modern Canis gene pool. PMID:26018528

  15. Unique inhibitory cascade pattern of molars in canids contributing to their potential to evolutionary plasticity of diet

    PubMed Central

    Asahara, Masakazu

    2013-01-01

    Developmental origins that guide the evolution of dental morphology and dental formulae are fundamental subjects in mammalian evolution. In a previous study, a developmental model termed the inhibitory cascade model was established. This model could explain variations in relative molar sizes and loss of the lower third molars, which sometimes reflect diet, in murine rodents and other mammals. Here, I investigated the pattern of relative molar sizes (inhibitory cascade pattern) in canids, a taxon exhibiting a wide range of dietary habits. I found that interspecific variation in canid molars suggests a unique inhibitory cascade pattern that differs from that in murine rodents and other previously reported mammals, and that this variation reflects dietary habits. This unique variability in molars was also observed in individual variation in canid species. According to these observations, canid species have greater variability in the relative sizes of first molars (carnassials), which are functionally important for dietary adaptation in the Carnivora. In conclusion, an inhibitory cascade that differs from that in murine rodents and other mammals may have contributed to diverse dietary patterns and to their parallel evolution in canids. PMID:23467478

  16. Ancient DNA analysis of the oldest canid species from the siberian arctic and genetic contribution to the domestic dog.

    PubMed

    Lee, Esther J; Merriwether, D Andrew; Kasparov, Alexei K; Nikolskiy, Pavel A; Sotnikova, Marina V; Pavlova, Elena Yu; Pitulko, Vladimir V

    2015-01-01

    Modern Arctic Siberia provides a wealth of resources for archaeological, geological, and paleontological research to investigate the population dynamics of faunal communities from the Pleistocene, particularly as the faunal material coming from permafrost has proven suitable for genetic studies. In order to examine the history of the Canid species in the Siberian Arctic, we carried out genetic analysis of fourteen canid remains from various sites, including the well-documented Upper Paleolithic Yana RHS and Early Holocene Zhokhov Island sites. Estimated age of samples range from as recent as 1,700 years before present (YBP) to at least 360,000 YBP for the remains of the extinct wolf, Canis cf. variabilis. In order to examine the genetic affinities of ancient Siberian canids species to the domestic dog and modern wolves, we obtained mitochondrial DNA control region sequences and compared them to published ancient and modern canid sequences. The older canid specimens illustrate affinities with pre-domestic dog/wolf lineages while others appear in the major phylogenetic clades of domestic dogs. Our results suggest a European origin of domestic dog may not be conclusive and illustrates an emerging complexity of genetic contribution of regional wolf breeds to the modern Canis gene pool. PMID:26018528

  17. The Nematode Caenorhabditis Elegans.

    ERIC Educational Resources Information Center

    Kenyon, Cynthia

    1988-01-01

    Discusses advantages of nematode use for studying patterns of cell division, differentiation, and morphogenesis. Describes nematode development. Cites experimental approaches available for genetic studies. Reviews the topics of control of cell division and differentiation, the nervous system, and muscle assembly and function of the organism. (RT)

  18. Chemical Communicators in Nematodes

    PubMed Central

    Huettel, R. N.

    1986-01-01

    Chemical signals released by one organism and perceived by another organism are classified as semiochemicals. Semiochemicals are divided into pheromones, which elicit intraspecific responses, and allelochemics, which elicit interspecific responses. Nematodes utilize and (or) recognize signals from both categories of semiochemicals. The existence of pheromones, specifically sex and aggregation pheromones, has been demonstrated in numerous plant and animal parasitic and free-living nematodes. Sex pheromones have been isolated and purified from Nippostrongylus brasiliensis and Heterodera glycines, and epidietic pheromones have been shown to be responsible for initiation of dauer juvenile formation in Caenorhabditis elegans. Allelochemics cause interspecific responses in insects and other invertebrates but are only postulated to occur in nematodes. Food-finding behavior of nematodes is almost certainly caused by host-released allelochemic messengers. Understanding of the behavioral responses and the chemical messengers that affect bioregulation of various processes in nematodes will influence future management strategies. PMID:19294130

  19. Wild canids as sentinels of ecological health: a conservation medicine perspective

    PubMed Central

    Aguirre, A Alonso

    2009-01-01

    The extinction of species across the globe is accelerating, directly or indirectly due to human activities. Biological impoverishment, habitat fragmentation, climate change, increasing toxification, and the rapid global movement of people and other living organisms have worked synergistically to diminish ecosystem function. This has resulted in unprecedented levels of disease emergence, driven by human-induced environmental degradation, which poses a threat to the survival and health of biodiversity. The emerging discipline of conservation medicine addresses these concerns through the following entities: humans; global climate; habitat destruction and alteration; biodiversity, including wildlife populations; domestic animals; and pathogens, parasites and pollutants. Furthermore, conservation medicine focuses on explicit linkages between these entities. As a crisis discipline, the usefulness of conservation medicine ultimately will depend on its applicability to solving problems. The perspectives and scientific findings of conservation medicine provide input into biomedical education; and policy and management of ecosystems, habitats and imperiled species. A sentinel species is one that has presented itself, or has been selected, to provide insight into the state (health) of an ecosystem, based on user-defined (e.g., researchers, conservationists or policymakers) objectives (e.g., disease, parasites, toxics, climate change, habitat destruction), coupled with the utility and vulnerability of this species to the perceived stress. The scientific information generated by the sentinel species should empower stakeholders and decision-makers to take mitigative action or support predictive capabilities; the "utility" of the species selected should consider its value and relevance to conservationists and to society at large (e.g., education and outreach; social sciences). Wild canids may serve as excellent sentinel species of emerging canine vector-borne diseases. Several canine vector-borne diseases or antibodies to these pathogens have been identified in wild canids including visceral leishmaniosis, Lyme disease, heartworm, hepatozoonosis and anaplasmosis to name a few. These reports are relatively recent as they relate to wildlife-domestic animal interactions, globalisation, translocations, habitat fragmentation and climate change. These pathogens and their relationship to wild canids are described herein. Further research needs to be performed to elucidate the role of the 36 extant species of wild canids in the epidemiology of canine vector-borne diseases. PMID:19426446

  20. Detection of Angiostrongylus cantonensis in the Blood and Peripheral Tissues of Wild Hawaiian Rats (Rattus rattus) by a Quantitative PCR (qPCR) Assay.

    PubMed

    Jarvi, Susan I; Pitt, William C; Farias, Margaret E; Shiels, Laura; Severino, Michael G; Howe, Kathleen M; Jacquier, Steven H; Shiels, Aaron B; Amano, Karis K; Luiz, Blaine C; Maher, Daisy E; Allison, Maureen L; Holtquist, Zachariah C; Scheibelhut, Neil T

    2015-01-01

    The nematode Angiostrongylus cantonensis is a rat lungworm, a zoonotic pathogen that causes human eosinophilic meningitis and ocular angiostrongyliasis characteristic of rat lungworm (RLW) disease. Definitive diagnosis is made by finding and identifying A. cantonensis larvae in the cerebral spinal fluid or by using a custom immunological or molecular test. This study was conducted to determine if genomic DNA from A. cantonensis is detectable by qPCR in the blood or tissues of experimentally infected rats. F1 offspring from wild rats were subjected to experimental infection with RLW larvae isolated from slugs, then blood or tissue samples were collected over multiple time points. Blood samples were collected from 21 rats throughout the course of two trials (15 rats in Trial I, and 6 rats in Trial II). In addition to a control group, each trial had two treatment groups: the rats in the low dose (LD) group were infected by approximately 10 larvae and the rats in the high dose (HD) group were infected with approximately 50 larvae. In Trial I, parasite DNA was detected in cardiac bleed samples from five of five LD rats and five of five HD rats at six weeks post-infection (PI), and three of five LD rats and five of five HD rats from tail tissue. In Trial II, parasite DNA was detected in peripheral blood samples from one of two HD rats at 53 minutes PI, one of two LD rats at 1.5 hours PI, one of two HD rats at 18 hours PI, one of two LD rats at five weeks PI and two of two at six weeks PI, and two of two HD rats at weeks five and six PI. These data demonstrate that parasite DNA can be detected in peripheral blood at various time points throughout RLW infection in rats. PMID:25910229

  1. Iterative adaptive radiations of fossil canids show no evidence for diversity-dependent trait evolution.

    PubMed

    Slater, Graham J

    2015-04-21

    A long-standing hypothesis in adaptive radiation theory is that ecological opportunity constrains rates of phenotypic evolution, generating a burst of morphological disparity early in clade history. Empirical support for the early burst model is rare in comparative data, however. One possible reason for this lack of support is that most phylogenetic tests have focused on extant clades, neglecting information from fossil taxa. Here, I test for the expected signature of adaptive radiation using the outstanding 40-My fossil record of North American canids. Models implying time- and diversity-dependent rates of morphological evolution are strongly rejected for two ecologically important traits, body size and grinding area of the molar teeth. Instead, Ornstein-Uhlenbeck processes implying repeated, and sometimes rapid, attraction to distinct dietary adaptive peaks receive substantial support. Diversity-dependent rates of morphological evolution seem uncommon in clades, such as canids, that exhibit a pattern of replicated adaptive radiation. Instead, these clades might best be thought of as deterministic radiations in constrained Simpsonian subzones of a major adaptive zone. Support for adaptive peak models may be diagnostic of subzonal radiations. It remains to be seen whether early burst or ecological opportunity models can explain broader adaptive radiations, such as the evolution of higher taxa. PMID:25901311

  2. A genome-wide perspective on the evolutionary history of enigmatic wolf-like canids

    PubMed Central

    vonHoldt, Bridgett M.; Pollinger, John P.; Earl, Dent A.; Knowles, James C.; Boyko, Adam R.; Parker, Heidi; Geffen, Eli; Pilot, Malgorzata; Jedrzejewski, Wlodzimierz; Jedrzejewska, Bogumila; Sidorovich, Vadim; Greco, Claudia; Randi, Ettore; Musiani, Marco; Kays, Roland; Bustamante, Carlos D.; Ostrander, Elaine A.; Novembre, John; Wayne, Robert K.

    2011-01-01

    High-throughput genotyping technologies developed for model species can potentially increase the resolution of demographic history and ancestry in wild relatives. We use a SNP genotyping microarray developed for the domestic dog to assay variation in over 48K loci in wolf-like species worldwide. Despite the high mobility of these large carnivores, we find distinct hierarchical population units within gray wolves and coyotes that correspond with geographic and ecologic differences among populations. Further, we test controversial theories about the ancestry of the Great Lakes wolf and red wolf using an analysis of haplotype blocks across all 38 canid autosomes. We find that these enigmatic canids are highly admixed varieties derived from gray wolves and coyotes, respectively. This divergent genomic history suggests that they do not have a shared recent ancestry as proposed by previous researchers. Interspecific hybridization, as well as the process of evolutionary divergence, may be responsible for the observed phenotypic distinction of both forms. Such admixture complicates decisions regarding endangered species restoration and protection. PMID:21566151

  3. Next-generation nematode genomes 

    E-print Network

    Kumar, Sujai

    2013-06-29

    The first metazoan to be sequenced was a nematode (Caenorhabditis elegans), and understanding the genome of this model organism has led to many insights about all animals. Although eleven nematode genomes have been ...

  4. Roles of Steroids in Nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The inability of nematodes to biosynthesize steroids de novo and the resulting dependence of parasitic nematodes upon their hosts have enhanced the importance of elucidating the metabolism of sterols and the hormonal and other functions of steroids in nematodes. Biochemical research has revealed th...

  5. Molecular characterization of Hepatozoon spp. infection in endangered Indian wild felids and canids.

    PubMed

    Pawar, Rahul Mohanchandra; Poornachandar, Anantula; Srinivas, Pasham; Rao, Kancharapu Ramachandra; Lakshmikantan, Uthandaraman; Shivaji, Sisinthy

    2012-05-25

    Hepatozoon species are parasites that infect a wide variety of domestic and wild animals. The objective of this study was to perform the molecular detection and characterization of Hepatozoon spp. in Asiatic lion, Indian tiger, Indian leopard, Indian wild dog, Indian domestic dog and cat based on partial 18S rRNA gene sequences from Hepatozoon spp. in the naturally infected animals. Hepatozoon spp. could be detected in blood samples of 5 out of 9 Asiatic lions, 2 out of 5 Indian tigers, 2 out of 4 Indian leopards and 2 out of 2 Indian wild dogs and, 2 out of 4 domestic cats and 2 out of 3 domestic dog samples by PCR. Sequencing of PCR amplicon and BLAST analysis of partial 18S rRNA gene sequences indicated that the Hepatozoon spp. in Asiatic lion, Bengal tiger, Indian leopard and domestic cat was Hepatozoon felis (98-99% similarity) and in the Indian wild and domestic dog the phylogenetic neighbour was Hepatozoon canis (97-100% similarity). Presence of H. felis and H. canis in both domestic and wild animals suggested that they are not host specific and the same parasite causes infection in domestic and wild felids and canids in India and from different parts of the world. To our knowledge, this is the first report on detection and molecular characterization of H. felis infection in Asiatic lions, Indian tigers, Indian leopards and H. canis in Indian wild dog. Hepatozoon spp. may be a potential pathogen and an opportunistic parasite in immuno-compromised animals and could thus represent a threat to endangered Indian wild felids and canids. PMID:22154254

  6. Anisakid Nematodes and Anisakiasis

    Microsoft Academic Search

    A. J. Lymbery; F. Y. Cheah

    \\u000a Anisakiasis (anisakidosis) refers to infection of people with larval stages of ascaridoid nematodes belonging to the family\\u000a Anisakidae (and possibly also\\u000a Raphidascarididae). These worms, commonly called anisakids, utilize aquatic mammals, piscivorous birds, aquatic reptiles,\\u000a or fish as definitive hosts, and aquatic invertebrates and fish as intermediate or paratenic hosts.

  7. High within-host genetic variation of the nematode Spirocerca lupi in a high-density urban dog population.

    PubMed

    de Waal, Pamela J; Gous, Annemarie; Clift, Sarah J; Greeff, Jaco M

    2012-06-01

    The nematode worm Spirocerca lupi has a cosmopolitan distribution and can cause the death of its final canid host, typically dogs. While its life cycle, which involves a coprophagous beetle intermediate host, a number of non-obligatory vertebrate paratenic hosts and a canid final host, is well understood, surprisingly little is known about its transmission dynamics and population genetic structure. Here we sequenced cox1 to quantify genetic variation and the factors that limit gene flow in a 300 km(2) area in South Africa. Three quarters of the genetic variation, was explained by differences between worms from the same host, whereas a quarter of the variation was explained by differences between worms from different hosts. With the help of a newly derived model we conclude that while the offspring from different infrapopulations mixes fairly frequently in new hosts, the level of admixture is not enough to homogenize the parasite populations among dogs. Small infrapopulation sizes along with clumped transmission may also result in members of infrapopulations being closely related. PMID:22226763

  8. A longitudinal study of Angiostrongylus cantonensis in an urban population of Rattus norvegicus in Brazil: the influences of seasonality and host features on the pattern of infection

    PubMed Central

    2014-01-01

    Background The nematode Angiostrongylus cantonensis is a zoonotic parasite and the most important cause of eosinophilic meningitis worldwide in humans. In Brazil, this disease has been reported in the states of Espírito Santo and Pernambuco. The parasite has been detected in the naturally infected intermediate host, in the states of Rio de Janeiro, Pernambuco and Santa Catarina. The murid Rattus norvegicus R. rattus were recently reported to be naturally infected in Brazil. In this study, we conducted a two-year investigation of the dissemination pattern of A. cantonensis in R. norvegicus in an urban area of Rio de Janeiro state, Brazil, and examined the influence of seasonality, year, host weight and host gender on parasitological parameters of A. cantonensis in rats. Methods The study was conducted in an area of Trindade, São Gonçalo municipality, Rio de Janeiro, Brazil. Prevalence of infected rats, intensity and abundance of A. cantonensis were calculated, and generalized linear models were created and compared to verify the contribution of host gender, host weight, year and seasonality to the variations in A. cantonensis abundance and prevalence in rats. Results The prevalence of A. cantonensis infection was stable during the rainy (71%, CI 58.9- 81.6) and dry seasons (71%, CI 57.9-80.8) and was higher in older rats and in females. Seasonality, host weight (used as a proxy of animal age) and gender were all contributing factors to variation in parasite abundance, with females and heavier (older) animals showing larger abundance of parasites, and extreme values of parasite abundance being more frequent in the dry season. Conclusions The high prevalence of this parasite throughout the study suggests that its transmission is stable and that conditions are adequate for the spread of the parasite to previously unaffected areas. Dispersion of the parasite to new areas may be mediated by males that tend to have larger dispersal ability, while females may be more important for maintaining the parasite on a local scale due to their higher prevalence and abundance of infection. A multidisciplinary approach considering the ecological distribution of the rats and intermediate hosts, as well as environmental features is required to further understand the dynamics of angiostrongyliasis. PMID:24612453

  9. Use of volatile organic components in scat to identify canid species

    USGS Publications Warehouse

    Burnham, E.; Bender, L.C.; Eiceman, G.A.; Pierce, K.M.; Prasad, S.

    2008-01-01

    Identification of wildlife species from indirect evidence can be an important part of wildlife management, and conventional +methods can be expensive or have high error rates. We used chemical characterization of the volatile organic constituents (VOCs) in scat as a method to identify 5 species of North American canids from multiple individuals. We sampled vapors of scats in the headspace over a sample using solid-phase microextraction and determined VOC content using gas chromatography with a flame ionization detector. We used linear discriminant analysis to develop models for differentiating species with bootstrapping to estimate accuracy. Our method correcdy classified 82.4% (bootstrapped 95% CI = 68.8-93.8%) of scat samples. Red fox (Vulpes vulpes) scat was most frequendy misclassified (25.0% of scats misclassified); red fox was also the most common destination for misclassified samples. Our findings are the first reported identification of animal species using VOCs in vapor emissions from scat and suggest that identification of wildlife species may be plausible through chemical characterization of vapor emissions of scat.

  10. Evidence of Coat Color Variation Sheds New Light on Ancient Canids

    PubMed Central

    Ollivier, Morgane; Tresset, Anne; Hitte, Christophe; Petit, Coraline; Hughes, Sandrine; Gillet, Benjamin; Duffraisse, Marilyne; Pionnier-Capitan, Maud; Lagoutte, Laetitia; Arbogast, Rose-Marie; Balasescu, Adrian; Boroneant, Adina; Mashkour, Marjan; Vigne, Jean-Denis; Hänni, Catherine

    2013-01-01

    We have used a paleogenetics approach to investigate the genetic landscape of coat color variation in ancient Eurasian dog and wolf populations. We amplified DNA fragments of two genes controlling coat color, Mc1r (Melanocortin 1 Receptor) and CBD103 (canine-?-defensin), in respectively 15 and 19 ancient canids (dogs and wolf morphotypes) from 14 different archeological sites, throughout Asia and Europe spanning from ca. 12 000 B.P. (end of Upper Palaeolithic) to ca. 4000 B.P. (Bronze Age). We provide evidence of a new variant (R301C) of the Melanocortin 1 receptor (Mc1r) and highlight the presence of the beta-defensin melanistic mutation (CDB103-K locus) on ancient DNA from dog-and wolf-morphotype specimens. We show that the dominant KB allele (CBD103), which causes melanism, and R301C (Mc1r), the variant that may cause light hair color, are present as early as the beginning of the Holocene, over 10 000 years ago. These results underline the genetic diversity of prehistoric dogs. This diversity may have partly stemmed not only from the wolf gene pool captured by domestication but also from mutations very likely linked to the relaxation of natural selection pressure occurring in-line with this process. PMID:24098367

  11. Gas sensing in nematodes.

    PubMed

    Carrillo, M A; Hallem, E A

    2015-06-01

    Nearly all animals are capable of sensing changes in environmental oxygen (O2) and carbon dioxide (CO2) levels, which can signal the presence of food, pathogens, conspecifics, predators, or hosts. The free-living nematode Caenorhabditis elegans is a powerful model system for the study of gas sensing. C. elegans detects changes in O2 and CO2 levels and integrates information about ambient gas levels with other internal and external cues to generate context-appropriate behavioral responses. Due to its small nervous system and amenability to genetic and genomic analyses, the functional properties of its gas-sensing microcircuits can be dissected with single-cell resolution, and signaling molecules and natural genetic variations that modulate gas responses can be identified. Here, we discuss the neural basis of gas sensing in C. elegans, and highlight changes in gas-evoked behaviors in the context of other sensory cues and natural genetic variations. We also discuss gas sensing in other free-living nematodes and parasitic nematodes, focusing on how gas-sensing behavior has evolved to mediate species-specific behavioral requirements. PMID:24906953

  12. RNAi Effector Diversity in Nematodes

    Microsoft Academic Search

    Johnathan J. Dalzell; Paul McVeigh; Neil D. Warnock; Makedonka Mitreva; David Mc K. Bird; Pierre Abad; Colin C. Fleming; Tim A. Day; Angela Mousley; Nikki J. Marks; Aaron G. Maule

    2011-01-01

    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

  13. Tawny frogmouths and brushtail possums as sentinels for Angiostrongylus cantonensis, the rat lungworm.

    PubMed

    Ma, Gemma; Dennis, Michelle; Rose, Karrie; Spratt, David; Spielman, Derek

    2013-02-18

    The objective of this study was to determine the prevalence of angiostrongylosis in tawny frogmouths (Podargus strigoides) and brushtail possums (Trichosurus vulpecula) with signs of neurological disease, and to describe the clinicopathological features of angiostrongylosis in both species. Tawny frogmouths and brushtail possums with signs of neurological disease were sampled from the Sydney metropolitan area between October 1998 and June 2010. Samples from 100 tawny frogmouths and 31 brushtail possums from the Australian Registry of Wildlife Health (ARWH), the Wildlife Assistance and Information Foundation (WAIF) and Wildlife Health and Conservation Centre (WHCC), University of Sydney were examined. Histological examinations of the brain, spinal cord and other available tissues were used to characterize the disease responsible for each animal's clinical signs. Of the 100 tawny frogmouths with neurological disease examined, angiostrongylosis was considered responsible in 80 (80%), traumatic injury in 17 (17%), protozoal infection in 3 (3%) and other diseases in 2 (2%) and the cause of clinical signs was unknown in 10 (10%). Eleven tawny frogmouths presenting with neurological signs associated with head trauma had concurrent angiostrongylosis. Of the 31 brushtail possums, Wobbly Possum Syndrome (WPS) was diagnosed in 21 (68%), angiostrongylosis in 4 (13%) and other diseases in the remaining 6 (19%). Angiostrongylosis was overrepresented in hand reared juvenile possums. Cases of angiostrongylosis in tawny frogmouths followed a strong seasonal pattern peaking through late summer and autumn. The results confirm that Angiostrongylus cantonensis is endemic in Sydney, Australia and that tawny frogmouths could be important sentinels for this zoonotic parasite. PMID:23218219

  14. Eosinophilic Meningitis Attributable to Angiostrongylus cantonensis Infection in Hawaii: Clinical Characteristics and Potential Exposures

    PubMed Central

    Hochberg, Natasha S.; Blackburn, Brian G.; Park, Sarah Y.; Sejvar, James J.; Effler, Paul V.; Herwaldt, Barbara L.

    2011-01-01

    The most common infectious cause of eosinophilic meningitis is Angiostrongylus cantonensis, which is transmitted largely by consumption of snails/slugs. We previously identified cases of angiostrongyliasis that occurred in Hawaii from 2001 to 2005; the highest incidence was on the island of Hawaii. We now report symptoms, laboratory parameters, and exposures. Eighteen patients were evaluated; 94% had headache, and 65% had sensory symptoms (paresthesia, hyperesthesia, and/or numbness). These symptoms lasted a median of 17 and 55 days, respectively. Three persons recalled finding a slug in their food/drink. Case-patients on the island of Hawaii were more likely than case-patients on other islands to consume raw homegrown produce in a typical week (89% versus 0%, P < 0.001) and to see snails/slugs on produce (56% versus 0%, P = 0.03). Residents and travelers should be aware of the potential risks of eating uncooked produce in Hawaii, especially if it is from the island of Hawaii and locally grown. PMID:21976573

  15. Changes in the calcium metabolism of Biomphalaria glabrata experimentally infected with Angiostrongylus cantonensis.

    PubMed

    Tunholi-Alves, V M; Tunholi, V M; Garcia, J Silva; Costa-Neto, S F; Maldonado, A; Santos, M A J; Thiengo, S C; Pinheiro, J

    2014-06-01

    Levels of calcium in the haemolymph and reserves in the shell of Biomphalaria glabrata experimentally infected by Angiostrongylus cantonensis were determined for the first time. At the same time, histochemical analyses of the digestive gland of infected and uninfected snails were performed to better understand the possible changes in metabolism of calcium in these organisms. After 1, 2 and 3 weeks of infection, the snails were dissected for collection of haemolymph and separation of tissues. The highest calcium concentrations in the haemolymph were found 2 weeks after infection, with a 39.61% increase in relation to the respective control group. However, there was a significant reduction in the concentration of this ion in the haemolymph of infected snails after 1 week of infection in relation to the uninfected specimens. In parallel, intense hypocalcification was shown in the shell of infected snails 1 and 2 weeks after infection, differing significantly in relation to the respective control groups. Morphological changes in the digestive gland of infected snails were also observed, confirming the role of this ion as an important element in the parasite encapsulation process. PMID:23290340

  16. Characterization and immunolocalization of mutated ornithine decarboxylase antizyme from Angiostrongylus cantonensis.

    PubMed

    Chen, Jing; Liu, Qian; Yang, Xiao; Wu, Xiansheng; Zhang, Dongjing; He, Ai; Zhan, Ximei

    2013-08-01

    Ornithine decarboxylase antizyme (OAZ), a prominent regulator of cell proliferation, DNA/RNA transformation and tumorigenesis, can bind to ornithine decarboxylase (ODC) and facilitate its degradation. Expression of OAZ requires a unique ribosomal frame shift that is regulated by levels of polyamine in the cell. In this study, we cloned an OAZ gene with the +1 ribosomal frame-shift from a fourth-stage larvae cDNA library of Angiostrongylus cantonensis. We removed one nucleotide to express the gene without polyamine. The sequence analysis showed that the deleted-mutation ornithine decarboxylase antizyme (DM-AcOAZ) contained a conservative domain related to other species OAZ. Quantitative real-time PCR revealed that DM-AcOAZ was expressed in L3 and L4 stages and adult female worms. More notably the expression level is the highest in the adult female stage. Immunohistochemical studies indicated that DM-AcOAZ was specifically localized in the uterus, oocyte and intestine in adult female worms. MTT assays showed that in DM-AcOAZ transfected HeLa cells, cell proliferation is inhibited. In conclusion, DM-AcOAZ may be a female-enriched protein and may involved in the cell proliferation in A. cantonensis. PMID:23816446

  17. Angiostrongylus cantonensis: experimental study on the susceptibility of apple snails, Pomacea canaliculata compared to Pila polita.

    PubMed

    Tesana, Smarn; Srisawangwong, Tuanchai; Sithithaworn, Paiboon; Laha, Thewarach

    2008-04-01

    Six groups (15 snails/group) of Pomacea canaliculata and Pila polita were infected orally with 0 (control), 200, 400, 800, 1600 and 3200 first-stage Angiostrongylus cantonensis larvae (L1). The respective mean+/-SD third stage larvae (L3) worm recovery 1-month post-infection (p.i.) for P. canaliculata was 0, 1.4+/-5.42 (0.7%), 0.13+/-0.35 (0.03%), 0.07+/-0.26 (0.009%), 0.07+/-0.26 (0.004%), 0, and for P. polita 0, 64.33+/-21.38 (32.25%), 115.36+/-36.82 (28.93%), 265.33+/-90.01 (33.27%), 471.33+/-92.98 (29.60%) and 849.00+/-243.23 (26.61%). The susceptibility of A. cantonensis in P. polita was dose-dependent (p<0.001). In the three groups (nine snails/group) of P. polita given 500 L1, we studied the distribution of L3 in the internal organs (i.e., foot, head+esophagus, kidney, albumin gland, mantle, intestine, digestive gland) and found the highest density after 1, 2 and 3 months p.i. in the mantle at 29.37%, 31.09% and 37.45%. The infection rate in P. canaliculata was too low to study distribution rates. PMID:18154954

  18. Loop-mediated isothermal amplification: rapid detection of Angiostrongylus cantonensis infection in Pomacea canaliculata

    PubMed Central

    2011-01-01

    Background Angiostrongylus cantonensis is a zoonotic parasite that causes eosinophilic meningitis in humans. The most common source of infection with A. cantonensis is the consumption of raw or undercooked mollusks (e.g., snails and slugs) harbouring infectious third-stage larvae (L3). However, the parasite is difficult to identify in snails. The purpose of this study was to develop a quick, simple molecular method to survey for A. cantonensis in intermediate host snails. Findings We used a loop-mediated isothermal amplification (LAMP) assay, which was performed using Bst DNA polymerase. Reactions amplified the A. cantonensis 18S rRNA gene and demonstrated high sensitivity; as little as 1 fg of DNA was detected in the samples. Furthermore, no cross-reactivity was found with other parasites such as Toxoplasma gondii, Plasmodium falciparum, Schistosoma japonicum, Clonorchis sinensis, Paragonimus westermani and Anisakis. Pomacea canaliculata snails were exposed to A. cantonensis first-stage larvae (L1) in the laboratory, and L3 were observed in the snails thirty-five days after infection. All nine samples were positive as determined by the LAMP assay for A. cantonensis, which was identified as positive by using PCR and microscopy, this demonstrates that LAMP is sensitive and effective for diagnosis. Conclusions LAMP is an appropriate diagnostic method for the routine identification of A. cantonensis within its intermediate host snail P. canaliculata because of its simplicity, sensitivity, and specificity. It holds great promise as a useful monitoring tool for A. cantonensis in endemic regions. PMID:22023992

  19. A Comparison of Facial Color Pattern and Gazing Behavior in Canid Species Suggests Gaze Communication in Gray Wolves (Canis lupus)

    PubMed Central

    Ueda, Sayoko; Kumagai, Gaku; Otaki, Yusuke; Yamaguchi, Shinya; Kohshima, Shiro

    2014-01-01

    As facial color pattern around the eyes has been suggested to serve various adaptive functions related to the gaze signal, we compared the patterns among 25 canid species, focusing on the gaze signal, to estimate the function of facial color pattern in these species. The facial color patterns of the studied species could be categorized into the following three types based on contrast indices relating to the gaze signal: A-type (both pupil position in the eye outline and eye position in the face are clear), B-type (only the eye position is clear), and C-type (both the pupil and eye position are unclear). A-type faces with light-colored irises were observed in most studied species of the wolf-like clade and some of the red fox-like clade. A-type faces tended to be observed in species living in family groups all year-round, whereas B-type faces tended to be seen in solo/pair-living species. The duration of gazing behavior during which the facial gaze-signal is displayed to the other individual was longest in gray wolves with typical A-type faces, of intermediate length in fennec foxes with typical B-type faces, and shortest in bush dogs with typical C-type faces. These results suggest that the facial color pattern of canid species is related to their gaze communication and that canids with A-type faces, especially gray wolves, use the gaze signal in conspecific communication. PMID:24918751

  20. Water Developments and Canids in Two North American Deserts: A Test of the Indirect Effect of Water Hypothesis

    PubMed Central

    Hall, Lucas K.; Larsen, Randy T.; Knight, Robert N.; Bunnell, Kevin D.; McMillan, Brock R.

    2013-01-01

    Anthropogenic modifications to landscapes intended to benefit wildlife may negatively influence wildlife communities. Anthropogenic provisioning of free water (water developments) to enhance abundance and distribution of wildlife is a common management practice in arid regions where water is limiting. Despite the long-term and widespread use of water developments, little is known about how they influence native species. Water developments may negatively influence arid-adapted species (e.g., kit fox, Vulpes macrotis) by enabling water-dependent competitors (e.g., coyote, Canis latrans) to expand distribution in arid landscapes (i.e., indirect effect of water hypothesis). We tested the two predictions of the indirect effect of water hypothesis (i.e., coyotes will visit areas with free water more frequently and kit foxes will spatially and temporally avoid coyotes) and evaluated relative use of free water by canids in the Great Basin and Mojave Deserts from 2010 to 2012. We established scent stations in areas with (wet) and without (dry) free water and monitored visitation by canids to these sites and visitation to water sources using infrared-triggered cameras. There was no difference in the proportions of visits to scent stations in wet or dry areas by coyotes or kit foxes at either study area. We did not detect spatial (no negative correlation between visits to scent stations) or temporal (no difference between times when stations were visited) segregation between coyotes and kit foxes. Visitation to water sources was not different for coyotes between study areas, but kit foxes visited water sources more in Mojave than Great Basin. Our results did not support the indirect effect of water hypothesis in the Great Basin or Mojave Deserts for these two canids. PMID:23844097

  1. An evaluation of the PCR-RFLP technique to aid molecular-based monitoring of felids and canids in India

    PubMed Central

    2010-01-01

    Background The order Carnivora is well represented in India, with 58 of the 250 species found globally, occurring here. However, small carnivores figure very poorly in research and conservation policies in India. This is mainly due to the dearth of tested and standardized techniques that are both cost effective and conducive to small carnivore studies in the field. In this paper we present a non-invasive genetic technique standardized for the study of Indian felids and canids with the use of PCR amplification and restriction enzyme digestion of scat collected in the field. Findings Using existing sequences of felids and canids from GenBank, we designed primers from the 16S rRNA region of the mitochondrial genome and tested these on ten species of felids and five canids. We selected restriction enzymes that would cut the selected region differentially for various species within each family. We produced a restriction digestion profile for the potential differentiation of species based on fragment patterns. To test our technique, we used felid PCR primers on scats collected from various habitats in India, representing varied environmental conditions. Amplification success with field collected scats was 52%, while 86% of the products used for restriction digestion could be accurately assigned to species. We verified this through sequencing. A comparison of costs across the various techniques currently used for scat assignment showed that this technique was the most practical and cost effective. Conclusions The species-specific key developed in this paper provides a means for detailed investigations in the future that focus on elusive carnivores in India and this approach provides a model for other studies in areas of Asia where many small carnivores co-occur. PMID:20525407

  2. Molecular phylogeography of Angiostrongylus cantonensis (Nematoda: Angiostrongylidae) and genetic relationships with congeners using cytochrome b gene marker.

    PubMed

    Yong, Hoi-Sen; Eamsobhana, Praphathip; Song, Sze-Looi; Prasartvit, Anchana; Lim, Phaik-Eem

    2015-08-01

    Angiostrongylus cantonensis is an important emerging zoonotic parasite causing human eosinophilic meningitis (or meningoencephalitis) in many parts of the world. To-date there is only a single study using mitochondrial cytochrome b (CYTB) gene to determine its genetic structure in eight geographical localities in Thailand. The present study examined the molecular phylogeography of this rat lungworm and its phylogenetic relationship with congeners using CYTB gene marker. A total of 15 CYTB haplotypes was found in 37 sequences from 14 geographical localities (covering north, west, east, central and south regions) in Thailand. These CYTB haplotypes were distinct from those of A. cantonensis for China and Hawaii. In Thailand, some CYTB haplotypes appeared to be confined to specific geographical localities. The partial CYTB DNA nucleotide sequences separated unequivocally the A. cantonensis isolates of Thailand, China and Hawaii as well as the congeners Angiostrongylus malaysiensis, A. costaricensis and Angiostrongylus vasorum, with A. malaysiensis grouped with A. cantonensis and A. costaricensis grouped with A. vasorum. Likewise the congeners of Metastrongylus and Onchocerca genera could also be clearly differentiated. The present study added two new definitive hosts (Bandicota savilei and Rattus losea) and three new localities (Mae Hong Son in the north, Tak in the west, and Phang Nga in the south) for A. malaysiensis in Thailand, indicating its wide occurrence in the country. Three CYTB haplotypes were found in the Thailand samples of A. malaysiensis. In addition to differentiation of congeners, CYTB gene marker could be used for determining the genetic diversity of a given population/taxon. PMID:25930187

  3. Nematodes in Texas Golf Courses 

    E-print Network

    Crow, William T.

    2000-04-10

    Plant parasitic nematodes are microscopic roundworms that feed on plant roots. In turfgrasses they cause damage similar to that of water stress, nutrient deficiency or root diseases. Golf course managers can use this publication to learn about...

  4. The moss fauna 2: Nematodes

    Microsoft Academic Search

    Ian M. Kinchin

    1989-01-01

    The biology of the nematode species found living in moss cushions is considered. Particular attention is paid to the methods used by the animals which enable them to live in an environment which suffers periodic desiccation.

  5. The role of wild canids and felids in spreading parasites to dogs and cats in Europe. Part I: Protozoa and tick-borne agents

    E-print Network

    Otranto, Domenico; Cantacessi, Cinzia; Pfeffer, Martin; Dantas-Torres, Filipe; Brianti, Emanuele; Deplazes, Peter; Genchi, Claudio; Guberti, Vittorio; Capelli, Gioia

    2015-05-08

    are known to occur in Europe (Sillero-Zubiri, 2009; Sunquist and Sunquist, 2009), i.e. five canids (the wolf, Canis lupus; the golden jackal, Canis aureus; the raccoon dog, Nyctereutes procyonoides; the artic fox, Alopex lagopus, and the red fox, Vulpes...

  6. A Serological Survey of Infectious Disease in Yellowstone National Park’s Canid Community

    PubMed Central

    Almberg, Emily S.; Mech, L. David; Smith, Douglas W.; Sheldon, Jennifer W.; Crabtree, Robert L.

    2009-01-01

    Background Gray wolves (Canis lupus) were reintroduced into Yellowstone National Park (YNP) after a >70 year absence, and as part of recovery efforts, the population has been closely monitored. In 1999 and 2005, pup survival was significantly reduced, suggestive of disease outbreaks. Methodology/Principal Findings We analyzed sympatric wolf, coyote (Canis latrans), and red fox (Vulpes vulpes) serologic data from YNP, spanning 1991–2007, to identify long-term patterns of pathogen exposure, identify associated risk factors, and examine evidence for disease-induced mortality among wolves for which there were survival data. We found high, constant exposure to canine parvovirus (wolf seroprevalence: 100%; coyote: 94%), canine adenovirus-1 (wolf pups [0.5–0.9 yr]: 91%, adults [?1 yr]: 96%; coyote juveniles [0.5–1.5 yrs]: 18%, adults [?1.6 yrs]: 83%), and canine herpesvirus (wolf: 87%; coyote juveniles: 23%, young adults [1.6–4.9 yrs]: 51%, old adults [?5 yrs]: 87%) suggesting that these pathogens were enzootic within YNP wolves and coyotes. An average of 50% of wolves exhibited exposure to the protozoan parasite, Neospora caninum, although individuals’ odds of exposure tended to increase with age and was temporally variable. Wolf, coyote, and fox exposure to canine distemper virus (CDV) was temporally variable, with evidence for distinct multi-host outbreaks in 1999 and 2005, and perhaps a smaller, isolated outbreak among wolves in the interior of YNP in 2002. The years of high wolf-pup mortality in 1999 and 2005 in the northern region of the park were correlated with peaks in CDV seroprevalence, suggesting that CDV contributed to the observed mortality. Conclusions/Significance Of the pathogens we examined, none appear to jeopardize the long-term population of canids in YNP. However, CDV appears capable of causing short-term population declines. Additional information on how and where CDV is maintained and the frequency with which future epizootics might be expected might be useful for future management of the Northern Rocky Mountain wolf population. PMID:19756151

  7. A serological survey of infectious disease in yellowstone national park's canid community

    USGS Publications Warehouse

    Almberg, E.S.; Mech, L.D.; Smith, D.W.; Sheldon, J.W.; Crabtree, R.L.

    2009-01-01

    Background: Gray wolves (Canis lupus) were reintroduced into Yellowstone National Park (YNP) after a >70 year absence, and as part of recovery efforts, the population has been closely monitored. In 1999 and 2005, pup survival was significantly reduced, suggestive of disease outbreaks. Methodology/Principal Findings: We analyzed sympatric wolf, coyote (Canis latrans), and red fox (Vulpes vulpes) serologic data from YNP, spanning 1991-2007, to identify long-term patterns of pathogen exposure, identify associated risk factors, and examine evidence for disease-induced mortality among wolves for which there were survival data. We found high, constant exposure to canine parvovirus (wolf seroprevalence: 100%; coyote: 94%), canine adenovirus-1 (wolf pups [0.5-0.9 yr]: 91%, adults [???1 yr]: 96%; coyote juveniles [0.5-1.5 yrs]: 18%, adults [???1.6 yrs]: 83%), and canine herpesvirus (wolf: 87%; coyote juveniles: 23%, young adults [1.6-4.9 yrs]: 51%, old adults [???5 yrs]: 87%) suggesting that these pathogens were enzootic within YNP wolves and coyotes. An average of 50% of wolves exhibited exposure to the protozoan parasite, Neospora caninum, although individuals' odds of exposure tended to increase with age and was temporally variable. Wolf, coyote, and fox exposure to canine distemper virus (CDV) was temporally variable, with evidence for distinct multi-host outbreaks in 1999 and 2005, and perhaps a smaller, isolated outbreak among wolves in the interior of YNP in 2002. The years of high wolf-pup mortality in 1999 and 2005 in the northern region of the park were correlated with peaks in CDV seroprevalence, suggesting that CDV contributed to the observed mortality. Conclusions/Significance: Of the pathogens we examined, none appear to jeopardize the long-term population of canids in YNP. However, CDV appears capable of causing short-term population declines. Additional information on how and where CDV is maintained and the frequency with which future epizootics might be expected might be useful for future management of the Northern Rocky Mountain wolf population.

  8. Epidemiological survey of Angiostrongylus cantonensis in the west-central region of Guangdong Province, China.

    PubMed

    Chen, Daixiong; Zhang, Yun; Shen, Haoxian; Wei, Yongfang; Huang, Di; Tan, Qiming; Lan, Xianqi; Li, Qingli; Chen, Zecheng; Li, Zhengtu; Ou, Le; Suen, Huibing; Ding, Xue; Luo, Xiaodong; Li, Xiaomin; Zhan, Ximei

    2011-08-01

    The study was to understand the Angiostrongylus cantonensis infectious situation of rodent definitive host, snail intermediate host, and local residents in the west-central region of Guangdong Province in China. The snails Achatina fulica and Pomacea canaliculata collected from the survey place were digested with artificial gastric juice, and the third-stage larvae of A. cantonensis in the snails were examined under microscope. The heart and lung of rats captured from the survey place were taken to check the adult of A. cantonensis. The questionnaire surveys related to the infection of A. cantonensis were taken in local residents randomly selected, and the IgG antibody against A. cantonensis was tested in those residents with enzyme-linked immunosorbent assay (ELISA). A total of 1,391 rats including eight kinds of rats, such as Rattus norvegicus, Rattus flavipectus, Bandicota indica, Rattus sladeni, Mus musculus, Rattus rattoides, Suncus Murinus, and Rattus confucianus, were examined and 132 of them were infected by A. cantonensis, with an average infection rate of 9.49% and a mean intensity of A. cantonensis in infected rats was 9.39. A total of 3,184 snails A. fulica and 3,723 snails P. canaliculata were detected. The average infection rates of them were 25.03% (797/3,184) and 6.50% (242/3,723), respectively. There were 180 positive samples of IgG antibody against A. cantonensis in 1,800 serum samples of the residents, with a positive rate of 10.00%. The west-central region of Guangdong Province is the natural focus of A. cantonensis. In comparison with the investigation results in other regions of China, the infection rate of rat definitive host is at the middle level; in the intermediate host, the infection rate of snail A. fulica is above the middle level, and the infection rate of snail Pomacea canaliculata is below the middle level. Some local residents had already been infected by A. cantonensis or at the risk of being infected. PMID:21301874

  9. MicroRNA expression profile in the third- and fourth-stage larvae of Angiostrongylus cantonensis.

    PubMed

    Li, Zhengyu; Chen, Xiaoguang; Zen, Xin; Liang, Jinyi; Wei, Jie; Lv, Zhiyue; Sun, Xi; Wu, Zhong-Dao

    2014-05-01

    The pathogenesis of angiostrongyliasis, resulting from the third-stage and the fourth-stage Angiostrongylus cantonensis larvae invasion of the human central nervous system, remains elusive. MicroRNAs are important regulators of gene expression and involved in many biological processes. The aim of this study was to determine and characterize miRNAs of third (L3) and fourth (L4) larvae of A. cantonensis by Solex deep sequencing. A total of 629 conserved miRNAs (526 and 376 miRNAs in L3 and L4 larvae of A. cantonensis, respectively) and three novel candidate miRNA from L3 and L4 larva of A. cantonensis were identified with bioinformatic analysis. There were 163 miRNAs upregulated and 54 miRNAs downregulated (fold changes ?5.0) in the L4 of A. cantonensis compared with that of L3 of A. cantonensis. Interestingly, Gene Ontology "biological process" classifications revealed that 26 miRNAs of significantly differential expression are associated with the immune system, which implies that these miRNAs might participate in the pathogenesis of angiostrongyliasis by regulating genes involved in immune response pathways. Furthermore, the differential expression patterns of 26 conserved miRNAs between L3 and L4 of A. cantonensis were verified. The results of real-time PCR and Northern blot showed that the aca-miR-124 and aca-miR-146a-5p have a low level expression in L3 larvae but high level expression in L4 larvae. Transfection of aca-miR-124 mimics alone significantly downregulated the mRNA expression of IL-6 and IL-1? and TNF-a in the N9 cells, compared to the combination transfection of aca-miR-124 mimics and inhibitor (P?

  10. Applying antibiotic selection markers for nematode genetics.

    PubMed

    Cornes, Eric; Quéré, Cécile A L; Giordano-Santini, Rosina; Dupuy, Denis

    2014-08-01

    Antibiotic selection markers have been recently developed in the multicellular model organism Caenorhabditis elegans and other related nematode species, opening great opportunities in the field of nematode transgenesis. Here we describe how these antibiotic selection systems can be easily combined with many well-established genetic approaches to study gene function, improving time- and cost-effectiveness of the nematode genetic toolbox. PMID:24821108

  11. Using entomopathogenic nematodes for crop insect control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this paper is to provide an overview on using entomopathogenic nematodes for insect pest control. Entomopathogenic nematodes (genera Steinernema and Heterorhabditis), are be used as natural biopesticides. Unlike plant parasitic nematodes, which can be serious crop pests, entomopat...

  12. Nematodes as Biological Control Agents of Insects

    NSDL National Science Digital Library

    0000-00-00

    Entomogenous nematodes are covered here on a short general page that includes several links, one of which is to a PDF with more extensive bio-control with nematodes information. Nine families of nematodes are mentioned which include species that sterilize, alter behavior, or simply kill the insect host.

  13. The occurrence of Angiostrongylus vasorum in terrestrial slugs from forests and parks in the Copenhagen area, Denmark.

    PubMed

    Ferdushy, T; Kapel, C M O; Webster, P; Al-Sabi, M N S; Grønvold, J

    2009-12-01

    A total of 298 slugs belonging to four species, Arion lusitanicus, A. ater, A. ater rufus and Limax maximus, were collected from six different localities within a radius of 30 km from Copenhagen and examined for naturally acquired Angiostrongylus vasorum infection. Overall, 28 slugs (9%) were infected, but the prevalence varied among the studied localities: Rude Forest (26%), West Amager Forest (18%), Jaegersborg Forest and Deer Park (8%), Frederiksberg Park (4%), Assistens Cemetery Park (0%) and Frederiksberg Botanical Garden (0%). Only third-stage larvae (L3) were recovered from the slugs, in numbers ranging from 1 to 392 per slug. Overall 82% of the infected slugs harboured fewer than 10 larvae and only 14% harboured over 100 larvae. PMID:19460193

  14. The occurrence of the rat lungworm, Angiostrongylus cantonensis, in nonindigenous snails in the Gulf of Mexico region of the United States

    USGS Publications Warehouse

    Teem, John L.; Qvarnstrom, Yvonne; Bishop, Henry S.; da Silva, Alexandre J.; Carter, Jacoby; White-McLean, Jodi; Smith, Trevor

    2013-01-01

    Nonindigenous apple snails, Pomacea maculata (formerly Pomacea insularum), are currently spreading rapidly through the southeastern United States. This mollusk serves as an intermediate host of the rat lungworm parasite (Angiostrongylus cantonensis), which can cause eosinophilic meningitis in humans who consume infected mollusks. A PCR-based detection assay was used to test nonindigenous apple snails for the rat lungworm parasite in Louisiana, Texas, Mississippi, and Florida. Only apple snails obtained from the New Orleans, Louisiana, area tested positive for the parasite. These results provide the first evidence that Angiostrongylus cantonensis does occur in nonindigenous apple snails in the southeastern United States. Additionally, Angiostrongylus cantonensis was identified in the terrestrial species Achatina fulica in Miami, Florida, indicating that rat lungworm is now established in Florida as well as Louisiana. Although the study suggests that the rat lungworm is not widespread in the Gulf States region, the infected snail population could still pose a risk to human health and facilitate the spread of the parasite to new areas.

  15. The Occurrence of the Rat Lungworm, Angiostrongylus cantonensis, in Nonindigenous Snails in the Gulf of Mexico Region of the United States

    PubMed Central

    Qvarnstrom, Yvonne; Bishop, Henry S; da Silva, Alexandre J; Carter, Jacoby; White-Mclean, Jodi; Smith, Trevor

    2013-01-01

    Nonindigenous apple snails, Pomacea maculata (formerly Pomacea insularum), are currently spreading rapidly through the southeastern United States. This mollusk serves as an intermediate host of the rat lungworm parasite (Angiostrongylus cantonensis), which can cause eosinophilic meningitis in humans who consume infected mollusks. A PCR-based detection assay was used to test nonindigenous apple snails for the rat lungworm parasite in Louisiana, Texas, Mississippi, and Florida. Only apple snails obtained from the New Orleans, Louisiana, area tested positive for the parasite. These results provide the first evidence that Angiostrongylus cantonensis does occur in nonindigenous apple snails in the southeastern United States. Additionally, Angiostrongylus cantonensis was identified in the terrestrial species Achatina fulica in Miami, Florida, indicating that rat lungworm is now established in Florida as well as Louisiana. Although the study suggests that the rat lungworm is not widespread in the Gulf States region, the infected snail population could still pose a risk to human health and facilitate the spread of the parasite to new areas. PMID:23901374

  16. The occurrence of the rat lungworm, Angiostrongylus cantonensis, in nonindigenous snails in the Gulf of Mexico region of the United States.

    PubMed

    Teem, John L; Qvarnstrom, Yvonne; Bishop, Henry S; da Silva, Alexandre J; Carter, Jacoby; White-McLean, Jodi; Smith, Trevor

    2013-06-01

    Nonindigenous apple snails, Pomacea maculata (formerly Pomacea insularum), are currently spreading rapidly through the southeastern United States. This mollusk serves as an intermediate host of the rat lungworm parasite (Angiostrongylus cantonensis), which can cause eosinophilic meningitis in humans who consume infected mollusks. A PCR-based detection assay was used to test nonindigenous apple snails for the rat lungworm parasite in Louisiana, Texas, Mississippi, and Florida. Only apple snails obtained from the New Orleans, Louisiana, area tested positive for the parasite. These results provide the first evidence that Angiostrongylus cantonensis does occur in nonindigenous apple snails in the southeastern United States. Additionally, Angiostrongylus cantonensis was identified in the terrestrial species Achatina fulica in Miami, Florida, indicating that rat lungworm is now established in Florida as well as Louisiana. Although the study suggests that the rat lungworm is not widespread in the Gulf States region, the infected snail population could still pose a risk to human health and facilitate the spread of the parasite to new areas. PMID:23901374

  17. Animal Manure Harms Entomopathogenic Nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal manure forms an alternative to synthetic fertilizer that provides the additional benefits of reducing nutrient leaching and soil erosion, and promoting greater soil biodiversity. Studies show that animal manures can suppress plant parasitic nematodes by increasing densities of antagonistic mi...

  18. Pine wood nematode, Bursaphelenchus xylophilus.

    PubMed

    Futai, Kazuyoshi

    2013-01-01

    After devastating vast areas of pine forests in Asian countries, the pine wilt disease spread into European forests in 1999 and is causing worldwide concern. This disease involves very complicated interactions between a pathogenic nematode, its vector beetle, host pine species, and fungi in dead hosts. Pathogenicity of the pine wood nematode is determined not only by its physical and chemical traits but also by its behavioral traits. Most life history traits of the pine wood nematode, such as its phoretic relationship with vector beetles, seem to be more effective in virulent than in avirulent isolates or species. As the pathogenicity determinants, secreted enzymes, and surface coat proteins are very important, they have therefore been studied intensively. The mechanism of quick death of a large pine tree as a result of infection by a tiny nematode could be ascribed to the dysfunction of the water-conducting system caused by the death of parenchyma cells, which must have originally evolved as an inherent resistant system. PMID:23663004

  19. Sequence data swell for nematodes

    Microsoft Academic Search

    Christiane Hertz-Fowler; Arnab Pain

    2008-01-01

    With more than 80,000 described species that are extremely diverse in terms of ecology and biology, the Nematoda phylum is one of the most common animal phyla. This month's Genome Watch describes genomes of several nematodes, including that of the human filarial parasite Brugia malayi.

  20. Detection of plant-parasitic nematode DNA in the gut of predatory and omnivorous nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A protocol for molecular gut analysis of nematodes was developed to determine if predatory and omnivorous nematodes from five different guilds prey on Rotylenchulus reniformis, Meloidogyne incognita, and Radopholus similis. Mononchoides, Mononchus, Neoactinolaimus, Mesodorylaimus, and Aporcelaimell...

  1. 77 FR 22185 - Golden Nematode; Removal of Regulated Areas

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-13

    ...Docket No. APHIS-2011-0036] Golden Nematode; Removal of Regulated Areas AGENCY...interim rule that amended the golden nematode regulations by removing the townships...these two townships are free of golden nematode, and we determined that regulation...

  2. Nematode.net: a tool for navigating sequences from parasitic and free-living nematodes

    Microsoft Academic Search

    Todd Wylie; John C. Martin; Michael Dante; Makedonka Dautova Mitreva; Sandra W. Clifton; Asif Chinwalla; Robert H. Waterston; Richard K. Wilson; James P. Mccarter

    2004-01-01

    Nematode.net (www.nematode.net) is a web- accessible resource for investigating gene sequen- ces from nematode genomes. The database is an outgrowth of the parasitic nematode EST project at Washington University's Genome Sequencing Center (GSC), St Louis. A sister project at the University of Edinburgh and the Sanger Institute is also underway. More than 295 000 ESTs have been generated from >30

  3. Nematode.net update 2008: improvements enabling more efficient data mining and comparative nematode genomics

    Microsoft Academic Search

    John C. Martin; Sahar Abubucker; Todd Wylie; Yong Yin; Zhengyuan Wang; Makedonka Dautova Mitreva

    2009-01-01

    Nematode.net (http:\\/\\/nematode.net) is a publicly available resource dedicated to the study of para- sitic nematodes. In 2000, the Genome Center at Washington University (GC) joined a consortium including the Nematode Genomics group in Edinburgh, and the Pathogen Sequencing Unit of the Sanger Institute to generate expressed seq- uence tags (ESTs) as an inexpensive and efficient solution for gene discovery in

  4. Molecular phylogeny of beetle associated diplogastrid nematodes suggests host switching rather than nematode-beetle coevolution

    Microsoft Academic Search

    Werner E Mayer; Matthias Herrmann; Ralf J Sommer

    2009-01-01

    BACKGROUND: Nematodes are putatively the most species-rich animal phylum. They have various life styles and occur in a variety of habitats, ranging from free-living nematodes in aquatic or terrestrial environments to parasites of animals and plants. The rhabditid nematode Caenorhabditis elegans is one of the most important model organisms in modern biology. Pristionchus pacificus of the family of the Diplogastridae

  5. CLUES TO STEROL FUNCTION IN NEMATODES: RECENT STUDIES WITH CAENORHABDITIS ELEGANS AND THE SOYBEAN CYST NEMATODE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nematodes possess a nutritional requirement for sterol because of their inability to biosynthesize sterols de novo. Consequently, parasitic nematodes must obtain sterols from their hosts and then metabolize them to other sterols and steroids required for nematode growth, development and reproductio...

  6. Root-knot Nematodes and Giant Cells

    Microsoft Academic Search

    Michael G. K. Jones; Derek B. Goto

    \\u000a Of all the economically important plant parasitic nematodes, root-knot nematodes (Meloidogyne species) are amongst the most widespread, the best recognized and most widely studied. This is partly because infected roots\\u000a develop galls where the nematodes feed, which with severe infection give roots a ‘knotted’ appearance. They have a remarkably\\u000a wide host range, and are ubiquitous especially in tropical and sub-tropical

  7. Development and validation of a real-time PCR assay for specific and sensitive detection of canid herpesvirus 1.

    PubMed

    Decaro, Nicola; Amorisco, Francesca; Desario, Costantina; Lorusso, Eleonora; Camero, Michele; Bellacicco, Anna Lucia; Sciarretta, Rossana; Lucente, Maria Stella; Martella, Vito; Buonavoglia, Canio

    2010-10-01

    A TaqMan-based real-time PCR assay targeting the glycoprotein B-encoding gene was developed for diagnosis of canid herpesvirus 1 (CHV-1) infection. The established assay was highly specific, since no cross-reactions were observed with other canine DNA viruses, including canine parvovirus type 2, canine minute virus, or canine adenovirus types 1 and 2. The detection limit was 10(1) and 1.20 x 10(1) DNA copies per 10 microl(-1) of template for standard DNA and a CHV-1-positive kidney sample, respectively: about 1-log higher than a gel-based PCR assay targeting the thymidine kinase gene. The assay was also reproducible, as shown by satisfactory low intra-assay and inter-assay coefficients of variation. CHV-1 isolates of different geographical origins were recognised by the TaqMan assay. Tissues and clinical samples collected from three pups which died of CHV-1 neonatal infection were also tested, displaying a wide distribution of CHV-l DNA in their organs. Unlike other CHV-1-specific diagnostic methods, this quantitative assay permits simultaneous detection and quantitation of CHV-1 DNA in a wide range of canine tissues and body fluids, thus providing a useful tool for confirmation of a clinical diagnosis, for the study of viral pathogenesis and for evaluation of the efficacy of vaccines and antiviral drugs. PMID:20674611

  8. The pathogenesis of optic neuritis caused by Angiostrongylus cantonensis in BALB/c mice

    PubMed Central

    2014-01-01

    Background One of the most common causes of meningitis in South East Asia is angiostrongyliasis or infection by the parasitic nematode Angiostrongyliasis cantonensis. Although this nematode usually resides in the pulmonary arteries of rats, its incidental occurence in other hosts such as humans can cause optic neuritis and lead to serious vision sequelae. Nevertheless, there are currently no systematic studies conducted in this area. Methods In order to study the pathogenesis of optic neuritis, mice were tried as a new animal model to study and challenge with A. cantonensis on 7d, 14d and 21d, respectively. Electroretinogram (ERG), visual evoked potential (VEP), ophthalmoscopy and histology were examined on day 7d, 14d and 21d and tribendimidine (TBD) was later used to treat optic neuritis on day 14d for a week to evaluate its therapeutic effects. Results Infection of A. cantonensis caused obvious inflammatory cell infiltration in the retina and optic nerve adventitia in day 14d and 21d followed by optic nerve fiber demyelination and retinal ganglion swelling at day 21d in the challenged mice. Prolonged VEP latency and decreased ERG amplitude were also observed on day 21. After treatment of TBD in the infected mice, retinal and optic nerve inflammation were alleviated, but VEP latency and ERG amplitude did not improve on day 21d and 28d. Conclusions The current study provides evidence that A. cantonensis can cause optic neuritis along with optic nerve demyelination and retinal ganglion cell damage in a mouse model. TBD alone treatment can improve the symptoms of optic neuritis, but does not aid in vision recovery, suggesting that both neuroprotective agents and Dexamethasone should be administered, along with treatment for the infection, to protect the optic nerve and ganglion cells. Furthermore, as the symptoms of optic neuritis caused by A. cantonensis in mice are similar to the optic neuritis in multiple sclerosis (MS) human patients, we suggest that the BALB/c mouse model provided in this study may be useful to explore therapies of optic neuritis in MS patients. PMID:25052055

  9. Angiostrongylus cantonensis: apoptosis of inflammatory cells induced by treatment with mebendazole or/and interleukin 12 in mice.

    PubMed

    Chuang, Chih-Cheng; Chen, Chi-Wu; Fan, Chia-Kwung; Su, Kua-Eyre; Tsai, Yueh-Ting; Chen, Chih-Li; Du, Wen-Yuan

    2007-03-01

    Angiostrongylus cantonensis is the major cause of human eosinophilic meningoencephalitis. ICR mice were infected orally with 35 infective larvae and sacrificed at 4-14 days, 25 days or 32 days post infection (dpi) for pathological and immunocytochemical examinations. In the non-treated group, no apoptosis signal was found in the meninges or parenchyma of the brains (4-14 dpi). Only a few apoptotic cells were noticed at 25 dpi (3%) and 32 dpi (10%). In the groups, the animals were given a single dose of mebendazole (20 mg/kg, per os at various times) or injections of interleukin 12 (IL-12) (10 ng/daily, intraperitoneally), all the animals were sacrificed at 14 dpi; the number of apoptotic cells was increased (17-21%). In the group that received a single dose of mebendazole (4 dpi) in combination with IL-12 injections (4-13 dpi), mild meningitis was observed, and most of the infiltrated inflammatory cells were in the apoptotic program (55%). Taken together, apoptosis of the inflammatory cells (most were eosinophils) could be induced when the infected mice were treated with mebendazole or/and IL-12. PMID:17049518

  10. Parasitic Nematodes - From Genomes to Control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The diseases caused by parasitic nematodes in domestic and companion animals are major factors that decrease production and quality of the agricultural products. Methods available for the control of the parasitic nematode infections are mainly based on chemical treatment, non-chemical management pra...

  11. Parasitic nematodes—From genomes to control

    Microsoft Academic Search

    Makedonka Mitreva; Dante S. Zarlenga; James P. McCarter; Douglas P. Jasmer

    2007-01-01

    The diseases caused by parasitic nematodes in domestic and companion animals are major factors that decrease production and quality of the agricultural products. Methods available for the control of the parasitic nematode infections are mainly based on chemical treatment, non-chemical management practices, immune modulation and biological control. However, even with integrated pest management that frequently combines these approaches, the effective

  12. Nematodes of Tropical Fruit Crops in Venezueka

    Microsoft Academic Search

    Renato Crozzoli

    Data on nematodes of main fruit crops in Venezuela are reviewed, including acerola, avocado, banana and plantain, breadfruit,\\u000a cashew, citrus, coconut, date palm, fig, grapevine, guava, mango, papaya, passionfruit, peach, pineapple, sapodilla and tamarind.\\u000a For each crop, main nematode species are reviewed, with dataon their distribution, damage and management

  13. Host Plant Resistance to Root-Knot Nematode in Cotton.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Host-plant resistance is economic and highly effective for root-knot nematode (RKN) Meloidogyne incognita control in cotton Gossypium hirsutum. Nematode resistance can protect cotton plants from direct injury due to nematode infection, and can protect against the root-knot nematode-Fusarium wilt dis...

  14. Host Plant Resistance to Root-Knot Nematode in Cotton.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Host-plant resistance is economic and highly effective for root-knot nematode (RKN) Meloidogyne incognita control in cotton Gossypium hirsutum. Nematode resistance can protect cotton plants from direct injury and crop loss from nematode infection, and can protect against the root-knot nematode-Fusar...

  15. Laser capture microdissection of nematode feeding cells.

    PubMed

    Ithal, Nagabhushana; Mitchum, Melissa G

    2011-01-01

    Obligate plant-parasitic nematodes, such as cyst nematodes (Heterodera and Globodera spp.) and root-knot nematodes (Meloidogyne spp.), form specialized feeding cells in host plant roots. These feeding cells provide the sole source of nutrition for the growth and reproduction of the nematode to complete its life cycle. Feeding cell formation involves complex physiological and morphological changes to normal root cells and is accompanied by dramatic changes in plant gene expression. The distinct features of feeding cells suggest that their formation entails a unique gene expression profile, a better understanding of which will assist in building models to explain signaling pathways that modulate transcriptional changes in response to nematodes. Ultimately, this knowledge can be used to design strategies to develop resistance against nematodes in crop plants. Feeding cells comprise a small fraction of the total root cell population, and identification of plant gene expression changes specific to these cells is difficult. Until recently, the specific isolation of nematode feeding cells could be accomplished only by manual dissection or microaspiration. These approaches are limited in that only mature feeding cells can be isolated. These limitations in tissue accessibility for macromolecule isolation at different stages of feeding cell development can be overcome through the use of laser microdissection (LM), a technique that enables the specific isolation of feeding cells from early to late stages for RNA isolation, amplification, and downstream analysis. PMID:21359812

  16. Nematodes associated with Dryocoetes uniseriatus (Coleoptera: Scolytidae).

    PubMed

    Shimizu, Ai; Tanaka, Ryusei; Akiba, Mitsuteru; Masuya, Hayato; Iwata, Ryûtarô; Fukuda, Kenji; Kanzaki, Natsumi

    2013-02-01

    We examined the nematode fauna associated with a species of bark beetle, Dryocoetes uniseriatus Eggers, as part of a biodiversity survey of forest beetle-associated nematodes. Collections were made in a pine stand at an experimental forest station in Ibaraki, Japan, from April to July of 2011; we examined the nematode association in 273 insects collected during this time. In total, 68% of the insects were associated with at least one species of nematode. Six species of nematodes, including two phoretic microbe feeders (Bursaphelenchus rainulfi Braasch & Burgermeister and Micoletzkya sp.), one insect parasite and nematode predator (Devibursaphelenchus cf. eproctatus), one insect parasite (Contortylenchus sp.), one insect parasite and potential microbe feeder (unidentified rhabditid parasite), and one potential insect parasite and fungal feeder (B. sinensis) were recovered from the beetles. D. cf. eproctatus was enclosed in nematangia on the backsides of the elytra, B. rainulfi was isolated from the backsides of the elytra or enclosed in nematangia, Micoletzkya sp. was isolated from under the elytra, Contortylenchus sp. and a rhabditid parasite parasitized the body cavity, and B. sinensis was found in the digestive tract of the insect. The association patterns of the nematode species varied seasonally, although definitive interactions among species (e.g., segregation, competition) were not observed. PMID:23339788

  17. Introduction Nematode spermatozoa are highly specialized

    E-print Network

    Maduro, Morris F.

    to immunoblot detection, Mass Spectrometry identification, in silico prediction of functional domains that these extracts share some of the properties observed in sperm extracts from the parasitic nematode Ascaris

  18. Conserving and Enhancing Biological Control of Nematodes

    PubMed Central

    Timper, Patricia

    2014-01-01

    Conservation biological control is the modification of the environment or existing practices to protect and enhance antagonistic organisms to reduce damage from pests. This approach to biological control has received insufficient attention compared with inundative applications of microbial antagonists to control nematodes. This review provides examples of how production practices can enhance or diminish biological control of plant-parasitic nematodes and other soilborne pests. Antagonists of nematodes can be enhanced by providing supplementary food sources such as occurs when organic amendments are applied to soil. However, some organic amendments (e.g., manures and plants containing allelopathic compounds) can also be detrimental to nematode antagonists. Plant species and genotype can strongly influence the outcome of biological control. For instance, the susceptibility of the plant to the nematode can determine the effectiveness of control; good hosts will require greater levels of suppression than poor hosts. Plant genotype can also influence the degree of rhizosphere colonization and antibiotic production by antagonists, as well the expression of induced resistance by plants. Production practices such as crop rotation, fallow periods, tillage, and pesticide applications can directly disrupt populations of antagonistic organisms. These practices can also indirectly affect antagonists by reducing their primary nematode host. One of the challenges of conservation biological control is that practices intended to protect or enhance suppression of nematodes may not be effective in all field sites because they are dependent on indigenous antagonists. Ultimately, indicators will need to be identified, such as the presence of particular antagonists, which can guide decisions on where it is practical to use conservation biological control. Antagonists can also be applied to field sites in conjunction with conservation practices to improve the consistency, efficacy, and duration of biological control. In future research, greater use should be made of bioassays that measure nematode suppression because changes in abundance of particular antagonists may not affect biological control of plant parasites. PMID:24987159

  19. 69 FR 21039 - Golden Nematode; Regulated Area

    Federal Register 2010, 2011, 2012, 2013, 2014

    2004-04-20

    We are adopting as a final rule, with one change, an interim rule that amended the golden nematode regulations by adding a field in Steuben County, NY, to the list of generally infested regulated areas. In this document, we are making an editorial change in order to correct a reference in the regulations. The interim rule was necessary to prevent the artificial spread of golden nematode to......

  20. The Nematode Caenorhabditis elegans: Oxidative Stress and Aging in the Nematode

    E-print Network

    Gems, David

    6 The Nematode Caenorhabditis elegans: Oxidative Stress and Aging in the Nematode Caenorhabditis that view oxidative damage as a potential primary cause of aging. These theories have framed to find clear evidence for many of the oxidative dam- age theories. In particular, they have failed

  1. UDP-Galactopyranose Mutase in Nematodes

    PubMed Central

    Wesener, Darryl A.; May, John F.; Huffman, Elizabeth M.; Kiessling, Laura L.

    2013-01-01

    Nematodes represent a diverse phylum of both free living and parasitic species. While the species Caenorhabditis elegans (C. elegans) is a valuable model organism, parasitic nematodes or helminths pose a serious threat to human health. Indeed, helminths cause many neglected tropical diseases that afflict humans. Nematode glycoconjugates have been implicated in evasive immunomodulation, a hallmark of nematode infections. One monosaccharide residue present in the glycoconjugates of several human pathogens is galactofuranose (Galf). This five-membered ring isomer of galactose has not been detected in mammals, making Galf metabolic enzymes attractive therapeutic targets. The only known pathway for biosynthetic incorporation of Galf into glycoconjugates depends upon generation of the glycosyl donor UDP-Galf by the flavoenzyme uridine 5’-diphosphate (UDP) galactopyranose mutase (UGM or Glf). A putative UGM encoding gene (glf-1) was recently identified in C. elegans. Because Galf has yet to be identified in any nematode glycan, we sought to assess the catalytic activity of the C. elegans glf-1 gene product (CeUGM). We found that CeUGM catalyzes the isomerization of UDP-Galf and UDP-galactopyranose (UDP-Galp). In the presence of enzyme, substrate, and a hydride source, a galactose–N5-FAD adduct was isolated, suggesting the CeUGM flavin adenine dinucleotide (FAD) cofactor serves as a nucleophile in covalent catalysis. Homology modeling and protein variants indicate that CeUGM possesses an active site similar to that of prokaryotic enzymes, despite the low sequence identity (~15%) between eukaryotic and prokaryotic UGM proteins. Even with the primary sequence differences, heterocyclic UGM inhibitors developed against prokaryotic proteins also inhibit CeUGM activity. We postulate that these inhibitors can serve as chemical probes of Galf in nematodes and as anthelmintic leads. Together, our data suggest that CeUGM facilitates the biosynthetic incorporation of Galf into nematode glycoconjugates through generation of the glycosyl donor UDP-Galf. PMID:23697711

  2. Original article Parasite nematode infections in Awassi adult sheep

    E-print Network

    Paris-Sud XI, Université de

    Original article Parasite nematode infections in Awassi adult sheep: distribution through Syrian were higher in flocks using wet night shelters. nematode / parasite / sheep / Syria / epidemiology Résumé ― Infestations des Ovins Awassi adultes par les nématodes parasites : distribution parmi

  3. Biological Control Potential of Neoaplectanid Nematodes

    PubMed Central

    Gaugler, Randy

    1981-01-01

    The neoaplectanids are among the most studied of all entomogenous nematodes. Because these nematodes kill their insect hosts, they are regarded as having excellent potential as biological control agents. While the host specificity of most entontogenous nematodes tends to limit their potential usefulness, the broad host range and high virulence of neoaplectanids make them attractive candidates for industrial development. Also, recent development of economical mass rearing procedures appears to make production on a commercial basis feasible. Infective stages may be stored for years trader various laboratory conditions. Although entomogenous nematodes, as parasites, are exempt from govermnent registration requirements, the mutualistic association of neoaplectanid nematodes with a bacterium will likely necessitate a detailed safety evaluation. Studies conducted to date indicate a lack of pathogenicity to mammals. Field trial success has been limited by the intolerance of infective stages to mffavorable environmental conditions, particularly low moisture. Applications against pests on exposed plant foliage have been especially disappointing. More encouraging anti consistent results have been obtained in more favorable environments, including soil and aquatic habitats, but the most promising treatment sites ntay be cryptic habitats where infective stages are shehered from environmental extremes. Cryptic habitats also exploit the ability of neoaplectanids to actively seek out hosts in recessed places where conventional insecticide applications are intpractical. PMID:19300757

  4. The apple snail Pomacea canaliculata, a novel vector of the rat lungworm, Angiostrongylus cantonensis: its introduction, spread, and control in China.

    PubMed

    Yang, Ting-Bao; Wu, Zhong-Dao; Lun, Zhao-Rong

    2013-06-01

    The freshwater apple snail Pomacea canaliculata was introduced to Taiwan then to mainland China in the early 1980s from Argentina, its native region, for the purpose of aquaculture. Because of the lack of natural enemies and its tolerance of a wide range of environmental conditions, both its abundance and distribution have dramatically increased and it has become a harmful species to local agriculture and other native species in many areas of China. Unfortunately, the snail also acts as an intermediate host of Angiostrongylus cantonensis, and has been implicated in transfer of the parasite to people, resulting in angiostrongyliasis manifested as eosinophilic meningitis. Efforts to prevent its further spread and population expansion were initiated many years ago, including the use of chemicals and biological control agents to control the snail. PMID:23901377

  5. The Apple Snail Pomacea canaliculata, a Novel Vector of the Rat Lungworm, Angiostrongylus cantonensis: its Introduction, Spread, and Control in China

    PubMed Central

    Wu, Zhong-Dao; Lun, Zhao-Rong

    2013-01-01

    The freshwater apple snail Pomacea canaliculata was introduced to Taiwan then to mainland China in the early 1980s from Argentina, its native region, for the purpose of aquaculture. Because of the lack of natural enemies and its tolerance of a wide range of environmental conditions, both its abundance and distribution have dramatically increased and it has become a harmful species to local agriculture and other native species in many areas of China. Unfortunately, the snail also acts as an intermediate host of Angiostrongylus cantonensis, and has been implicated in transfer of the parasite to people, resulting in angiostrongyliasis manifested as eosinophilic meningitis. Efforts to prevent its further spread and population expansion were initiated many years ago, including the use of chemicals and biological control agents to control the snail. PMID:23901377

  6. Site-Specific Detection and Management of Nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nematode distribution varies significantly throughout a field and is highly correlated to soil texture and other edaphic factors. Field-wide application results in nematicides being applied to areas without nematodes and the application of sub-effective levels in areas with high nematode densities. ...

  7. Plant parasitic nematode proteins and the host parasite interaction

    Microsoft Academic Search

    Rosane H. C. Curtis

    2007-01-01

    This review focuses on the proteins and secretions of sedentary plant parasitic nematodes potentially important for plant^ nematode interactions. These nematodes are well equipped for parasitism of plants. Having acquired the ability to manipulate fundamental aspects of plant biology, they are able to hijack host-cell development to make their feeding site. They feed exclusively from feeding sites as they complete

  8. Controlling the Pine-Killing Woodwasp, Sirex noctilio, with Nematodes

    E-print Network

    Chapter 12 Controlling the Pine-Killing Woodwasp, Sirex noctilio, with Nematodes Robin A. Bedding Abstract The pine-killing woodwasp Sirex noctilio, a native to Eurasia/Morocco, was accidentally introduced are described for liberating nematodes in pine plantations. The nematode has caused major crashes in S. noctilio

  9. Delayed response to ring nematode (Mesocriconema xenoplax) feeding on grape roots linked to vine carbohydrate reserves and nematode feeding pressure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The chronic impact of ring nematode (Mesocriconema xenoplax) feeding on grapevine (Vitis vinifera) was studied under controlled conditions. 'Pinot noir' grapevines were exposed to ring nematode or kept nematode-free for three growing seasons, and vines were either grown in full sunlight, 15% of full...

  10. Expressed sequence tags of the peanut pod nematode Ditylenchus africanus: The first transcriptome analysis of an Anguinid nematode

    Microsoft Academic Search

    Annelies Haegeman; Joachim Jacob; Bartel Vanholme; Tina Kyndt; Makedonka Mitreva; Godelieve Gheysen

    2009-01-01

    In this study, 4847 expressed sequenced tags (ESTs) from mixed stages of the migratory plant-parasitic nematode Ditylenchus africanus (peanut pod nematode) were investigated. It is the first molecular survey of a nematode which belongs to the family of the Anguinidae (order Rhabditida, superfamily Sphaerularioidea). The sequences were clustered into 2596 unigenes, of which 43% did not show any homology to

  11. Free-living and Plant-Parasitic Nematodes (Roundworms)

    NSDL National Science Digital Library

    Gregory L. Tylka (Iowa State University; )

    2001-04-09

    This resource serves as an introduction to the world of nematodes. The objectives of this exercise include introducing students to the world of nematodes, illustrating a method of extraction of nematodes from soil, and learning to differentiate stylet-bearing nematodes from free-living nematodes. This exercise will be most useful for grades 7-12 in classrooms where dissecting and compound microscopes are available. It requires minimal materials (funnels, screen, tubing, clamps, 2-ply tissues, ring stand, soil sample, and water) and preparation.

  12. Molecular phylogeny of beetle associated diplogastrid nematodes suggests host switching rather than nematode-beetle coevolution

    PubMed Central

    2009-01-01

    Background Nematodes are putatively the most species-rich animal phylum. They have various life styles and occur in a variety of habitats, ranging from free-living nematodes in aquatic or terrestrial environments to parasites of animals and plants. The rhabditid nematode Caenorhabditis elegans is one of the most important model organisms in modern biology. Pristionchus pacificus of the family of the Diplogastridae has been developed as a satellite model for comparison to C. elegans. The Diplogastridae, a monophyletic clade within the rhabditid nematodes, are frequently associated with beetles. How this beetle-association evolved and whether beetle-nematode coevolution occurred is still elusive. As a prerequisite to answering this question a robust phylogeny of beetle-associated Diplogastridae is needed. Results Sequences for the nuclear small subunit ribosomal RNA and for 12 ribosomal protein encoding nucleotide sequences were collected for 14 diplogastrid taxa yielding a dataset of 5996 bp of concatenated aligned sequences. A molecular phylogeny of beetle-associated diplogastrid nematodes was established by various algorithms. Robust subclades could be demonstrated embedded in a phylogenetic tree topology with short internal branches, indicating rapid ancestral divergences. Comparison of the diplogastrid phylogeny to a comprehensive beetle phylogeny revealed no major congruence and thus no evidence for a long-term coevolution. Conclusion Reconstruction of the phylogenetic history of beetle-associated Diplogastridae yields four distinct subclades, whose deep phylogenetic divergence, as indicated by short internal branch lengths, shows evidence for evolution by successions of ancient rapid radiation events. The stem species of the Diplogastridae existed at the same time period when the major radiations of the beetles occurred. Comparison of nematode and beetle phylogenies provides, however, no evidence for long-term coevolution of diplogastrid nematodes and their beetle hosts. Instead, frequent host switching is observed. The molecular phylogeny of the Diplogastridae provides a framework for further examinations of the evolution of these associations, for the study of interactions within the ecosystems, and for investigations of diplogastrid genome evolution. PMID:19703296

  13. PCR detection of potato cyst nematode.

    PubMed

    Reid, Alex

    2009-01-01

    Potato cyst nematode (PCN) is responsible for losses in potato production totalling millions of euros every year in the EC. It is important for growers to know which species is present in their land as this determines its subsequent use. The two species Globodera pallida and Globodera rostochiensis can be differentiated using an allele-specific PCR. PMID:19301763

  14. Plant Disease Lesson: Root-knot nematode

    NSDL National Science Digital Library

    Nathaniel A. Mitkowski (University of Rhode Island; )

    2003-09-17

    This plant disease lesson on Root-knot nematode (caused by Meloidogyne ) includes information on symptoms and signs, pathogen biology, disease cycle and epidemiology, disease management, and the significance of the disease. Selected references are listed and a glossary is also available for use with this resource.

  15. Nematodes: Model Organisms in High School Biology

    ERIC Educational Resources Information Center

    Bliss, TJ; Anderson, Margery; Dillman, Adler; Yourick, Debra; Jett, Marti; Adams, Byron J.; Russell, RevaBeth

    2007-01-01

    In a collaborative effort between university researchers and high school science teachers, an inquiry-based laboratory module was designed using two species of insecticidal nematodes to help students apply scientific inquiry and elements of thoughtful experimental design. The learning experience and model are described in this article. (Contains 4…

  16. MSP dynamics and retraction in nematode sperm

    Microsoft Academic Search

    Charles W. Wolgemuth; Long Miao; Orion Vanderlinde; Tom Roberts; George Oster

    2005-01-01

    Most eukaryotic cells can crawl over surfaces. In general, this motility requires three distinct actions: polymerization at the leading edge, adhesion to the substrate, and retraction at the rear. Recent in vitro experiments with extracts from spermatozoa from the nematode Ascaris suum suggest that retraction forces are generated by depolymerization of the Major Sperm Protein (MSP) cytoskeleton. Combining polymer entropy

  17. Mermithid Nematodes: In Vitro Culture Attempts

    PubMed Central

    Finney, Jean R.

    1981-01-01

    Few attempts at in vitro culture of mermithids have been undertaken. The various methods used to initiate cultures are described. The capacity of a range of media to promote growth and development of the nematodes has been evaluated and current approaches to in vitro outlined. PMID:19300762

  18. Plant Disease Lesson: Lesion nematode disease

    NSDL National Science Digital Library

    Eric L. Davis (North Carolina State University; )

    2000-10-30

    This plant disease lesson on Lesion nematode disease (caused by Pratylenchus) includes information on symptoms and signs, pathogen biology, disease cycle and epidemiology, disease management, and the significance of the disease. Selected references are listed and a glossary is also available for use with this resource.

  19. Diverse CLE peptides from cyst nematode species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant CLAVATA3/ESR (CLE)-like peptides play diverse roles in plant growth and development including maintenance of the stem cell population in the root meristem. Small secreted peptides sharing similarity to plant CLE signaling peptides have been isolated from several cyst nematode species including...

  20. Plant Disease Lesson: Soybean cyst nematode disease

    NSDL National Science Digital Library

    Eric L. Davis (North Carolina State University; )

    2000-07-25

    This plant disease lesson on Soybean cyst nematode disease (caused by Heterodera glycines) includes information on symptoms and signs, pathogen biology, disease cycle and epidemiology, disease management, and the significance of the disease. Selected references are listed and a glossary is also available for use with this resource.

  1. Absence of Wolbachia in Nonfilariid Nematodes

    PubMed Central

    Bordenstein, Seth R.; Fitch, David H. A.; Werren, John H.

    2003-01-01

    Intracellular bacteria of the genus Wolbachia are among the most abundant endosymbionts on the planet, occurring in at least two major phyla-the Arthropoda and Nematoda. Current surveys of Wolbachia distribution have found contrasting patterns within these groups. Whereas Wolbachia are widespread and occur in all three major subphyla of arthropods, with estimates placing them in at least several million arthropod species, the presence of nematodes carrying Wolbachia is currently confined to the filariids, in which they occur at appreciable frequencies. It has been hypothesized that Wolbachia entered the ancestor of modern-day filariids in a single acquisition event, and subsequently cospeciated with their filariid hosts. To further investigate this hypothesis, we examined the broader distribution of Wolbachia in nematodes using a polymerase chain reaction (PCR) assay in a diverse set of nonfilariid species. The assay consisted of three different types of PCR screens on adults of 20 secernentean nematode species (14 rhabditids, 2 strongylid parasites of vertebrates; 1 diplogasterid; 3 cephalobid relatives, 1 myolaim, and 1 filariid) and two adenophorean species (plectids). Two PCR screens were specific to the 16S rDNA and ftsZ protein coding gene of Wolbachia; and the third screen was specific to the 18S rDNA of the nematodes. Based upon our results, we conclude that Wolbachia are absent in all 21 non-filariid species encompassing all the major groups of the Secernentea and two species of Adenophorea, from which the Secernentea derived. The absence of Wolbachia in these non-filariids is consistent with the hypothesis that Wolbachia entered the nematode phylum once, in an ancestral lineage of extant filariids. PMID:19262760

  2. Top 10 plant-parasitic nematodes in molecular plant pathology.

    PubMed

    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. PMID:23809086

  3. Characterization of Root-Knot Nematode Resistance in Medicago truncatula.

    PubMed

    Dhandaydham, Murali; Charles, Lauren; Zhu, Hongyan; Starr, James L; Huguet, Thierry; Cook, Douglas R; Prosperi, Jean-Marie; Opperman, Charles

    2008-03-01

    Root knot (Meloidogyne spp.) and cyst (Heterodera and Globodera spp.) nematodes infect all important crop species, and the annual economic loss due to these pathogens exceeds $90 billion. We screened the worldwide accession collection with the root-knot nematodes Meloidogyne incognita, M. arenaria and M. hapla, soybean cyst nematode (SCN-Heterodera glycines), sugar beet cyst nematode (SBCN-Heterodera schachtii) and clover cyst nematode (CLCN-Heterodera trifolii), revealing resistant and susceptible accessions. In the over 100 accessions evaluated, we observed a range of responses to the root-knot nematode species, and a non-host response was observed for SCN and SBCN infection. However, variation was observed with respect to infection by CLCN. While many cultivars including Jemalong A17 were resistant to H. trifolii, cultivar Paraggio was highly susceptible. Identification of M. truncatula as a host for root-knot nematodes and H. trifolii and the differential host response to both RKN and CLCN provide the opportunity to genetically and molecularly characterize genes involved in plant-nematode interaction. Accession DZA045, obtained from an Algerian population, was resistant to all three root-knot nematode species and was used for further studies. The mechanism of resistance in DZA045 appears different from Mi-mediated root-knot nematode resistance in tomato. Temporal analysis of nematode infection showed that there is no difference in nematode penetration between the resistant and susceptible accessions, and no hypersensitive response was observed in the resistant accession even several days after infection. However, less than 5% of the nematode population completed the life cycle as females in the resistant accession. The remainder emigrated from the roots, developed as males, or died inside the roots as undeveloped larvae. Genetic analyses carried out by crossing DZA045 with a susceptible French accession, F83005, suggest that one gene controls resistance in DZA045. PMID:19259519

  4. Characterization of Root-Knot Nematode Resistance in Medicago truncatula

    PubMed Central

    Dhandaydham, Murali; Charles, Lauren; Zhu, Hongyan; Starr, James L.; Huguet, Thierry; Cook, Douglas R.; Prosperi, Jean-Marie; Opperman, Charles

    2008-01-01

    Root knot (Meloidogyne spp.) and cyst (Heterodera and Globodera spp.) nematodes infect all important crop species, and the annual economic loss due to these pathogens exceeds $90 billion. We screened the worldwide accession collection with the root-knot nematodes Meloidogyne incognita, M. arenaria and M. hapla, soybean cyst nematode (SCN-Heterodera glycines), sugar beet cyst nematode (SBCN-Heterodera schachtii) and clover cyst nematode (CLCN-Heterodera trifolii), revealing resistant and susceptible accessions. In the over 100 accessions evaluated, we observed a range of responses to the root-knot nematode species, and a non-host response was observed for SCN and SBCN infection. However, variation was observed with respect to infection by CLCN. While many cultivars including Jemalong A17 were resistant to H. trifolii, cultivar Paraggio was highly susceptible. Identification of M. truncatula as a host for root-knot nematodes and H. trifolii and the differential host response to both RKN and CLCN provide the opportunity to genetically and molecularly characterize genes involved in plant-nematode interaction. Accession DZA045, obtained from an Algerian population, was resistant to all three root-knot nematode species and was used for further studies. The mechanism of resistance in DZA045 appears different from Mi-mediated root-knot nematode resistance in tomato. Temporal analysis of nematode infection showed that there is no difference in nematode penetration between the resistant and susceptible accessions, and no hypersensitive response was observed in the resistant accession even several days after infection. However, less than 5% of the nematode population completed the life cycle as females in the resistant accession. The remainder emigrated from the roots, developed as males, or died inside the roots as undeveloped larvae. Genetic analyses carried out by crossing DZA045 with a susceptible French accession, F83005, suggest that one gene controls resistance in DZA045. PMID:19259519

  5. 7 CFR 301.85-9 - Movement of live golden nematodes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... false Movement of live golden nematodes. 301.85-9 Section 301...DOMESTIC QUARANTINE NOTICES Golden Nematode Quarantine and Regulations § 301.85-9 Movement of live golden nematodes. Regulations requiring a...

  6. Quantitative detection of the potato cyst nematode, Globodera pallida, and the beet cyst nematode, Heterodera schachtii, using Real-Time PCR with SYBR green I dye

    Microsoft Academic Search

    Mehrdad Madani; Sergei A. Subbotin; Maurice Moens

    2005-01-01

    The potato cyst nematode Globodera pallida and the beet cyst nematode Heterodera schachtii are major nematode pests in world agriculture. Precise identification and knowledge about the number of nematodes in field soil are necessary to develop effective integrated pest control. Here we report the results of the Real-Time PCR assay for the rapid detection and quantification of G. pallida and

  7. On the Methodology of Nematode Extraction from Field Samples: Density Flotation Techniques

    PubMed Central

    Viglierchio, David R.; Yamashita, Tom T.

    1983-01-01

    Density flotation has been frequently used for the extraction of nematodes from field samples. Density flotation curves for four nematode species and five solutes have been prepared. The curves confirm that flotation was governed by several factors: solute density, solute osmotic activity, and physiological properties of the nematode species. Nematode viability and function can be adversely affected by improper selection of solute for density extraction of nematodes; nevertheless, some nematode species can be enriched from mixtures by density and solute selection. PMID:19295831

  8. Serum concentrations of vitamin D metabolites, vitamins A and E, and carotenoids in six canid and four ursid species at four zoos.

    PubMed

    Crissey, S; Ange, K; Slifka, K; Bowen, P; Stacewicz-Sapuntzakis, M; Langman, C; Sadler, W; Ward, A

    2001-01-01

    Nutritional status for six captive canid species (n=34) and four captive ursid species (n=18) were analyzed. The species analyzed included: African wild dog (Lycaon pictus), arctic fox (Alopex lagopus), gray wolf (Canis lupus), maned wolf (Chrysocyon brachyurus), Mexican wolf (Canis lupus baleiyi), red wolf (Canis rufus), brown bear (Ursus arctos), polar bear (Ursus maritimus), spectacled bear (Tremarctos ornatus), and sun bear (Ursus malayanus). Diet information was collected for these animals from each participating zoo (Brookfield Zoo, Fort Worth Zoo, Lincoln Park Zoological Gardens, and North Carolina Zoological Park). The nutritional composition of the diet for each species at each institution met probable dietary requirements. Blood samples were collected from each animal and analyzed for vitamin D metabolites 25(OH)D and 1,25(OH)(2)D, vitamin A (retinol, retinyl stearate, retinyl palmitate), vitamin E (alpha-tocopherol and gamma-tocopherol) and selected carotenoids. Family differences were found for 25(OH)D, retinol, retinyl stearate, retinyl palmitate and gamma-tocopherol. Species differences were found for all detectable measurements. Carotenoids were not detected in any species. The large number of animals contributing to these data, provides a substantial base for comparing the nutritional status of healthy animals and the differences among them. PMID:11137448

  9. Nematode suppression with brassicaceous amendments: application based upon glucosinolate profiles

    Microsoft Academic Search

    I. A. Zasada; H. Ferris

    2004-01-01

    Glucosinolate profiles differ among plant species and their isothiocyanate (ITC) derivatives differ in toxicity to nematodes. Successful management of plant–parasitic nematodes by ITCs requires the incorporation of appropriate amounts of glucosinolate-containing biomass. Plant materials, containing glucosinolate-precursors of the ITCs most toxic to nematodes, were selected and applied to soil based upon ITC lethal concentration (LC) values. This provided a reliable

  10. Nematode responses to biosolids incorporation in five soil types

    Microsoft Academic Search

    G. W. Yeates; T. W. Speir; M. D. Taylor; L. Clucas; A. P. Schaik

    2006-01-01

    The impact of biosolids on soil processes in five soils under pasture was assessed. Five biosolid treatments (control, dried pellets, compost, biosolids at 200 kg N\\/ha, and biosolids at 800 kg N\\/ha) were mixed in 0- to 10-cm-deep soil in lysimeters each year. Nematodes were sampled after 2 years. Many of the nematode populations and indices showed significant soil effects. Nematode responses to

  11. Molecular Insights in the Susceptible Plant Response to Nematode Infection

    Microsoft Academic Search

    Godelieve Gheysen; Melissa G. Mitchum

    Sedentary endoparasitic nematodes have evolved sophisticated strategies to form permanent feeding sites within host plant\\u000a roots to ensure their survival. The process of feeding site formation entails an elaborate transformation of normal root cells\\u000a into enlarged, multinucleate, and metabolically active cell types to supply the nutritional needs of the nematode. The signal-exchange\\u000a that occurs between nematodes and their hosts to

  12. Degradation of the Plant Cell Wall by Nematodes

    Microsoft Academic Search

    Eric L. Davis; Annelies Haegeman; Taisei Kikuchi

    \\u000a Evidence from as early as the 1950’s that phytoparasitic nematodes could secrete enzymes to facilitate penetration of the\\u000a stylet through the host cell wall or to promote nematode migration within plant tissues was confirmed in 1998 with the report\\u000a of the first genes encoding endogenous endo-1,4-?-glucanases isolated from animals, the phytoparasitic cyst nematodes. Expressed\\u000a gene analyses and recent genome sequencing

  13. Exploring the transcriptome of the burrowing nematode Radopholus similis

    Microsoft Academic Search

    Joachim Jacob; Makedonka Mitreva; Bartel Vanholme; Godelieve Gheysen

    2008-01-01

    Radopholus similis is an important nematode pest on fruit crops in the tropics. Unraveling the transcriptome of this migratory plant-parasitic\\u000a nematode can provide insight in the parasitism process and lead to more efficient control measures. For the first high throughput\\u000a molecular characterization of this devastating nematode, 5,853 expressed sequence tags from a mixed stage population were\\u000a generated. Adding 1,154 tags

  14. Ectoparasitic Acugutturid Nematodes of Adult Lepidoptera

    PubMed Central

    Simmons, A. M.; Rogers, C. E.

    1996-01-01

    Noctuidonema guyaneme is an interesting ectoparasite of adult Lepidoptera that feeds on hosts from at least five families with its long stylet. Noctuidonema guyanense spends its entire life on the adult moth and is sustained as it is passed from moth to moth during host mating. Overlapping host generations are essential for parasite survival. This nematode occurs throughout tropical and subtropical America and is transported by at least one of its hosts, Spodoptera frugiperda, during migration to northern sites in the United States each spring. Noctuidonema guyanense debilitates its hosts. Research conducted to help determine the biological control importance of this nematode is reviewed. Two additional species, N. daptria and N. dibolia, are now known for Noctuidonema. PMID:19277339

  15. Immunity to gastrointestinal nematodes: mechanisms and myths

    PubMed Central

    Grencis, Richard K; Humphreys, Neil E; Bancroft, Allison J

    2014-01-01

    Immune responses to gastrointestinal nematodes have been studied extensively for over 80 years and intensively investigated over the last 30–40 years. The use of laboratory models has led to the discovery of new mechanisms of protective immunity and made major contributions to our fundamental understanding of both innate and adaptive responses. In addition to host protection, it is clear that immunoregulatory processes are common in infected individuals and resistance often operates alongside modulation of immunity. This review aims to discuss the recent discoveries in both host protection and immunoregulation against gastrointestinal nematodes, placing the data in context of the specific life cycles imposed by the different parasites studied and the future challenges of considering the mucosal/immune axis to encompass host, parasite, and microbiome in its widest sense. PMID:24942690

  16. Nematodes Associated with Plants from Naturally Acidic Wetlands Soil

    PubMed Central

    Cox, Robert John; Smart, Grover C.

    1994-01-01

    Four plants, Cyperus ochraceus, Eriocaulon compressum, Lythrum alatum, and Xyris jupicai, growing along the shoreline of an oligotrophic lake in north central Florida were sampled for nematodes. The nematodes recovered were placed in four trophic groups: bacterivores, herbivores, omnivores, and predators. When the nematodes on all plants were considered, 27% were bacterivores, 23% were herbivores, 7% were omnivores, and 43% were predators. Tripyla was the dominant predator and the dominant genus of all nematodes, and Malenchus was the dominant herbivore. Dominance was not clearly pronounced in the other trophic groups. PMID:19279927

  17. Nematodes associated with plants from naturally acidic wetlands soil.

    PubMed

    Cox, R J; Smart, G C

    1994-12-01

    Four plants, Cyperus ochraceus, Eriocaulon compressum, Lythrum alatum, and Xyris jupicai, growing along the shoreline of an oligotrophic lake in north central Florida were sampled for nematodes. The nematodes recovered were placed in four trophic groups: bacterivores, herbivores, omnivores, and predators. When the nematodes on all plants were considered, 27% were bacterivores, 23% were herbivores, 7% were omnivores, and 43% were predators. Tripyla was the dominant predator and the dominant genus of all nematodes, and Malenchus was the dominant herbivore. Dominance was not clearly pronounced in the other trophic groups. PMID:19279927

  18. Selectable genetic markers for nematode transgenesis

    Microsoft Academic Search

    Rosina Giordano-Santini; Denis Dupuy

    2011-01-01

    The nematode Caenorhabditis elegans has been used to study genetics and development since the mid-1970s. Over the years, the arsenal of techniques employed in\\u000a this field has grown steadily in parallel with the number of researchers using this model. Since the introduction of C. elegans transgenesis, nearly 20 years ago, this system has been extensively used in areas such as rescue

  19. Genome Analysis of Plant Parasitic Nematodes

    Microsoft Academic Search

    Pierre Abad; James P. McCarter

    \\u000a Plant nematology has entered an era of genomics with the completion of the genome sequences of two root knot nematode (RKN)\\u000a species: Meloidogyne incognita and M. hapla. Comparative analysis of these two RKN genomes reveals striking differences in their organizations and sheds light on the\\u000a mechanisms and evolution of parasitism. The M. hapla genome with 54 Mbp and 14,454 genes represents

  20. Assaying Environmental Nickel Toxicity Using Model Nematodes

    PubMed Central

    Rudel, David; Douglas, Chandler D.; Huffnagle, Ian M.; Besser, John M.; Ingersoll, Christopher G.

    2013-01-01

    Although nickel exposure results in allergic reactions, respiratory conditions, and cancer in humans and rodents, the ramifications of excess nickel in the environment for animal and human health remain largely undescribed. Nickel and other cationic metals travel through waterways and bind to soils and sediments. To evaluate the potential toxic effects of nickel at environmental contaminant levels (8.9-7,600 µg Ni/g dry weight of sediment and 50-800 µg NiCl2/L of water), we conducted assays using two cosmopolitan nematodes, Caenorhabditis elegans and Pristionchus pacificus. We assayed the effects of both sediment-bound and aqueous nickel upon animal growth, developmental survival, lifespan, and fecundity. Uncontaminated sediments were collected from sites in the Midwestern United States and spiked with a range of nickel concentrations. We found that nickel-spiked sediment substantially impairs both survival from larval to adult stages and adult longevity in a concentration-dependent manner. Further, while aqueous nickel showed no adverse effects on either survivorship or longevity, we observed a significant decrease in fecundity, indicating that aqueous nickel could have a negative impact on nematode physiology. Intriguingly, C. elegans and P. pacificus exhibit similar, but not identical, responses to nickel exposure. Moreover, P. pacificus could be tested successfully in sediments inhospitable to C. elegans. Our results add to a growing body of literature documenting the impact of nickel on animal physiology, and suggest that environmental toxicological studies could gain an advantage by widening their repertoire of nematode species. PMID:24116204

  1. Assaying environmental nickel toxicity using model nematodes

    USGS Publications Warehouse

    Rudel, David; Douglas, Chandler; Huffnagle, Ian; Besser, John M.; Ingersoll, Christopher G.

    2013-01-01

    Although nickel exposure results in allergic reactions, respiratory conditions, and cancer in humans and rodents, the ramifications of excess nickel in the environment for animal and human health remain largely undescribed. Nickel and other cationic metals travel through waterways and bind to soils and sediments. To evaluate the potential toxic effects of nickel at environmental contaminant levels (8.9-7,600 ?g Ni/g dry weight of sediment and 50-800 ?g NiCl2/L of water), we conducted assays using two cosmopolitan nematodes, Caenorhabditis elegans and Pristionchus pacificus. We assayed the effects of both sediment-bound and aqueous nickel upon animal growth, developmental survival, lifespan, and fecundity. Uncontaminated sediments were collected from sites in the Midwestern United States and spiked with a range of nickel concentrations. We found that nickel-spiked sediment substantially impairs both survival from larval to adult stages and adult longevity in a concentration-dependent manner. Further, while aqueous nickel showed no adverse effects on either survivorship or longevity, we observed a significant decrease in fecundity, indicating that aqueous nickel could have a negative impact on nematode physiology. Intriguingly, C. elegans and P. pacificus exhibit similar, but not identical, responses to nickel exposure. Moreover, P. pacificus could be tested successfully in sediments inhospitable to C. elegans. Our results add to a growing body of literature documenting the impact of nickel on animal physiology, and suggest that environmental toxicological studies could gain an advantage by widening their repertoire of nematode species.

  2. A White Paper on Nematode Comparative Genomics

    PubMed Central

    Bird, David McK.; Blaxter, Mark L.; McCarter, James P.; Mitreva, Makedonka; Sternberg, Paul W.; Thomas, W. Kelley

    2005-01-01

    In response to the new opportunities for genome sequencing and comparative genomics, the Society of Nematology (SON) formed a committee to develop a white paper in support of the broad scientific needs associated with this phylum and interests of SON members. Although genome sequencing is expensive, the data generated are unique in biological systems in that genomes have the potential to be complete (every base of the genome can be accounted for), accurate (the data are digital and not subject to stochastic variation), and permanent (once obtained, the genome of a species does not need to be experimentally re-sampled). The availability of complete, accurate, and permanent genome sequences from diverse nematode species will underpin future studies into the biology and evolution of this phylum and the ecological associations (particularly parasitic) nematodes have with other organisms. We anticipate that upwards of 100 nematode genomes will be solved to varying levels of completion in the coming decade and suggest biological and practical considerations to guide the selection of the most informative taxa for sequencing. PMID:19262884

  3. Reniform Nematode Resistance in Selected Soybean Cultivars

    PubMed Central

    Robbins, R. T.; Rakes, L.; Jackson, L. E.; Dombek, D. G.

    1999-01-01

    Two hundred eighty-two soybean cultivars from the variety testing programs of Arkansas and Mississippi were tested in greenhouse pot experiments during summer 1998 to identify soybean cultivars with resistance to the reniform nematode, Rotylenchulus reniformis. Also included in the tests were the resistant cultivars Forrest and Hartwig, the susceptible control Braxton, and fallow infested soil, which were used as controls. Numbers of reniform nematode extracted from the soil and roots and the ratio of the numbers reproducing on each cultivar compared to the number reproducing on Forrest are reported. Cultivars with reproduction not significantly different from Forrest were classified resistant, whereas those with greater reproductive indices were considered susceptible. One of the 18 cultivars of relative maturity group (RMG) ?4.4 was classified as resistant. For the 86 cultivars of RMG 4.5-4.9, 18 were found to be resistant. Of the 43 cultivars of RMG 5.0-5.4, 16 were resistant, while 43 of the 91 cultivars of RMG 5.5-5.9 were resistant. Fifteen of the cultivars with an RMG of ?6.0 were classed as resistant. These data will be useful in the selection of soybean cultivars to use in rotation with cotton to help control the reniform nematode. PMID:19270934

  4. Angiostrongylus cantonensis: tegumental and hypodermic alterations of the fourth-stage larvae following administration of tribendimidine in vivo and in vitro.

    PubMed

    Zeng, Xin; Wang, Juan; Wei, Jie; Wu, Feng; Fung, Feng; Wu, Xiaoying; Sun, Xi; Zheng, Huanqing; Lv, Zhiyue; Wu, Zhongdao

    2013-08-01

    Angiostrongylus cantonensis is a parasitic pathogen whose forth-stage larvae (L4) parasitize in the central nervous system (CNS) of the human cause severe eosinophilic encephalitis or meningoencephalitis. Previous study indicated an impressive anthelmintic efficacy of tribendimidine (TBD) against CNS parasitized L4 of A. cantonensis. Tegument of the larvae is the first physical barrier to protect them from attack by the host immune system. In the present study, tegumental and hypodermic alterations were observed by scanning electron microscopy and transmission electron microscopy after administration of TBD. During treatment of TBD in vivo, L4 presented wizened side sensor, disappearance of mastoids and longitudinal grain, prominent surface coat, heterogeneous tegumental layers, incompact hypodermic cell junctions, blurred myotube, and small scale of vacuole in a basal layer. After incubation with TBD in vitro, L4 exhibited a swollen side sensor and mastoids disappearance in head end. Abundant tegumental blebs and obvious deformation of both cross-grain and longitudinal grain were detected on the surface, and shrinkage of all tegumental layers, chaotic cell junction, turbid muscle cell, disappearance of myotubes, and vacuole-like changes were visible under the electron microscope. The results implied the potential mechanism of the anthelmintic effect of tribendimidine against L4 of A. cantonensis by direct damages to tegumental and hypodermic. PMID:23728774

  5. Activation of anaerobic metabolism in Biomphalaria glabrata (Mollusca: Gastropoda) experimentally infected by Angiostrongylus cantonensis (Nematoda, Metastrongylidae) by high-performance liquid chromatography.

    PubMed

    Tunholi-Alves, Vinícius Menezes; Tunholi, Victor Menezes; Castro, Rosane N; Sant'Ana, Luiza D'Oliveira; Santos-Amaral, Luciana; de Oliveira, Ana Paula Martins; Garcia, Juberlan; Thiengo, Silvana Carvalho; Pinheiro, Jairo; Maldonado, Arnaldo

    2014-02-01

    The activity of lactate dehydrogenase and the concentrations of glucose in the hemolymph and of glycogen in the digestive gland and cephalopedal mass of Biomphalaria glabrata experimentally infected with Angiostrongylus cantonensis were evaluated. Additionally, high performance liquid chromatography (HPLC) was used to determine the hemolymph concentrations of some carboxylic acids (oxalic, piruvic, lactic and succinic). After one, two and three weeks of infection, the snails were dissected to collect the hemolymph and separate the tissues. A significant reduction of the levels of glucose in the hemolymph was observed as of the first week of infection in relation to the control group. The lactate dehydrogenase activity of the infected group was significantly higher than the average of the control group. This increase was accompanied by a reduction of the levels of piruvic acid and an increase in the levels of lactic acid in the hemolymph of the parasited snails, confirming the acceleration of the anaerobic metabolism, necessary for the host to obtain energy and maintain its redox balance. In parallel, there was a decrease in the glycogen content of the storage tissues, with that reduction being significantly greater in the cephalopedal mass than the digestive gland, demonstrating that in this interaction system, the mobilization of glycogen was not sufficient to maintain and reestablish the normal glycemia of the infected snails. PMID:24042059

  6. Combined Treatment with Interleukin-12 and Mebendazole Lessens the Severity of Experimental Eosinophilic Meningitis Caused by Angiostrongylus cantonensis in ICR Mice

    PubMed Central

    Du, Wen-Yuan; Liao, Jiunn-Wang; Fan, Chia-Kwung; Su, Kua-Eyre

    2003-01-01

    Angiostrongylus cantonensis is the major cause of eosinophilic meningoencephalitis cases in Taiwan. Mice were orally infected with 35 infective larvae. One group of mice were given a single dose of mebendazole (20 mg/kg of body weight) per os at various times and examined at 14 days postinfection (dpi) for worm recovery rate and pathological studies. A 94 to 97% reduction in worm recovery was observed when medication was given at 4 to 5 dpi. Sections of the brains revealed that untreated infected mice developed typical severe eosinophilic meningoencephalitis. Meninges of these mice were thickened by massive infiltration of eosinophils, whereas only moderate pathological change was observed in the brains of mice that were treated with mebendazole at 4 dpi. Infected mice that received daily injections of 10 ng of interleukin-12 (IL-12) only for various numbers of days also exhibited moderate pathological changes in the brain. Eosinophil infiltration in the brains of these mice was low, and severe mechanical injuries in the parenchyma were observed. Treatment with mebendazole in combination with IL-12, however, resulted in low levels of worm recovery and dramatic lessening of the eosinophilic meningitis. A reverse transcriptase PCR assay of mRNA expression in the brain also revealed that the use of IL-12 had shifted the immune response of the mouse from Th2 type to Th1 type. This study could be used in developing strategies for the treatment of human angiostrongylosis. PMID:12819081

  7. Sex-determination gene and pathway evolution in nematodes

    E-print Network

    McQueen, Heather

    Sex-determination gene and pathway evolution in nematodes Paul Stothard and Dave Pilgrim* Summary at the molecular level. By identifying differences between the sex-determination mechanisms in C. elegans and other nematode species, it should be possible to under- stand how complex sex-determining pathways evolve

  8. Functional characterization of plant-parasitic cyst nematode CLE peptides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During root infection by plant-parasitic cyst nematodes, proteins originating in gland cells are secreted through the stylet into a cell near the vasculature of the host root for the initiation and maintenance of a specialized feeding structure (syncytium). Soybean cyst nematode (SCN; Heterodera gl...

  9. Characterization of a New Species of Cyst Nematode Parasitizing Corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Examination of soil around unthrifty corn roots in northwestern Tennessee (Obion County) in 2006 revealed high population densities of juvenile nematodes and lemon-shaped cysts. This nematode resembles Cactodera spp. in possessing a circumfenestrate vulva but lacking bullae and an underbridge. These...

  10. Nematode resistance and agronomic performance of LONREN and NEMSTACK lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    LONREN lines have resistance to reniform nematodes that was obtained from Gossypium longicalyx. The NEMSTACK lines have the same resistance recombined with the rkn-1 gene for resistance to root knot nematode from 'Acala NemX.' Different LONREN lines vary depending on whether the resistance gene was...

  11. Utilization of management zones for reniform nematodes in cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability to record measurements of soil electrical conductivity (EC) and field elevation at precise and closely-spaced GPS coordinates allows us to define nematode management zones based on field physical characteristics which may affect reniform nematode (Rotylenchulus reniformis) population lev...

  12. Inhibition of Nematode Infestation of Wheat Seedlings by Polygonum hydropiper

    Microsoft Academic Search

    N. C. Sukul

    1970-01-01

    SOME nematode diseases of crop plants are ameliorated by Brassica, Tagetes or Asparagus grown previously or concurrently in the same soil1-5. Toxic principles within their roots or exuded into the soil are thought to be responsible. Having observed that leaf and root extracts of Polygonum hydropiper L. have nematostatic properties against Rhabditis and other soil nematodes in vitro6, I decided

  13. Harmful Effects of Mustard Bio-fumigants on Entomopathogenic Nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Green manures, particularly mustards tilled into the soil preceding potato crops act as bio-fumigants that are toxic to plant parasitic nematodes, providing an alternative to synthetic soil fumigants. It is not known if mustard green manures also kill beneficial entomopathogenic nematodes (EPNs) tha...

  14. Sex-specific mating pheromones in the nematode Panagrellus redivivus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite advances in medicine and crop genetics, nematodes remain significant human pathogens and agricultural pests. This warrants investigation of alternative strategies for pest control, such as interference with pheromone-mediated reproduction. Because only two nematode species have had their phe...

  15. A SURVEY OF CYST NEMATODES (HETERODERA SPP.) IN NORTHERN EGYPT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Information concerning the occurrence and distribution of cyst nematodes (Heterodera spp.) in Egypt is important to assess their potential to cause economic damage to crop plants. A nematode survey was conducted in Alexandria and El-Behera Governorates in northern Egypt to identify the species of cy...

  16. Mapping the Dagger Nematode, Xiphinema index, resistance Gene

    Microsoft Academic Search

    Chin-Feng Hwang; Kenong Xu; Rong Hu; Summaira Riaz; M. Andrew Walker

    Vitis vinifera is susceptible to a wide range of pests and diseases including grapevine fanleaf virus (GFLV) and its dagger nematode vector, Xiphinema index. This virus\\/nematode complex causes fanleaf degeneration, which is considered to be one of the most severe viral diseases of grape. The virus spreads through propagation with virus-infected stock and by the feeding of X. index, which

  17. Biochemical Mechanisms for Regulating Protrusion by Nematode Major Sperm Protein

    E-print Network

    Wolgemuth, Charles

    Biochemical Mechanisms for Regulating Protrusion by Nematode Major Sperm Protein Jelena Stajic for this process is known. Nematode sperm utilize a cytoskeleton composed of Major Sperm Protein (MSP), which), and human neutrophils crawl to track down pathogens in the body (3). A single crawling cycle consists

  18. Directional movement of parasitic nematodes in response to electrical current

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Steinernematid nematodes are parasites that are important natural regulating agents of insect populations. The infective juvenile nematodes respond to a variety of stimuli that aid in survival and host finding. Host finding strategies among steinernematids differ along a continuum from ambush (sit...

  19. Soybean Cyst Nematode in North America - 55 Years Later

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean cyst nematode, Heterodera glycines, was first discovered in North America in 1954 in Hanover County, North Carolina, USA, when it was found on soybean in a field that had been planted to Easter lilies obtained from Japan prior to World War II. The nematode is now distributed throughout soybe...

  20. Sequence mining and transcript profiling to explore cyst nematode parasitism

    Microsoft Academic Search

    Axel A Elling; Makedonka Mitreva; Xiaowu Gai; John Martin; Justin Recknor; Eric L Davis; Richard S Hussey; Dan Nettleton; James P McCarter; Thomas J Baum

    2009-01-01

    BACKGROUND: Cyst nematodes are devastating plant parasites that become sedentary within plant roots and induce the transformation of normal plant cells into elaborate feeding cells with the help of secreted effectors, the parasitism proteins. These proteins are the translation products of parasitism genes and are secreted molecular tools that allow cyst nematodes to infect plants. RESULTS: We present here the

  1. MOLECULAR CHARACTERIZATION OF THE ACTIN GENE FROM CYST NEMATODES IN COMPARISON WITH THOSE FROM OTHER NEMATODES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Actin is an abundant, highly expressed and very conserved protein from the actin/heat shock protein70/sugar kinase superfamily. The full-length mRNA encoding actin was cloned and characterized from the plant-parasitic cyst nematodes Heterodera glycines and Globodera rostochiensis, and from the free-...

  2. Co-adaptation mechanisms in plant-nematode systems.

    PubMed

    Zinovieva, S V

    2014-01-01

    The review is aimed to analyze the biochemical and immune-breaking adaptive mechanisms established in evolution of plant parasitic nematodes. Plant parasitic nematodes are obligate, biotrophic pathogens of numerous plant species. These organisms cause dramatic changes in the morphology and physiology of their hosts. The group of sedentary nematodes which are among the most damaging plant-parasitic nematodes cause the formation of special organs called nematode feeding sites in the root tissue called syncytium (cyst nematodes, CN; Heterodera and Globodera spp.) or giant cells (root-knot nematodes, RKN; Meloidogyne spp.). The most pronounced morphological adaptations of nematodes for plant parasitism include a hollow, protrusible stylet (feeding spear) connected to three esophageal gland cells that express products secreted into plant tissues through the stylet. Several gene products secreted by the nematode during parasitism have been identified. The current battery of candidate parasitism proteins secreted by nematodes to modify plant tissues for parasitism includes cell-wall-modifying enzymes, multiple regulators of host cell cycle and metabolism, proteins that can localize near the plant cell nucleus, potential suppressors of host defense, and mimics of plant molecules. Plants are usually able to recognize and react to parasites by activating various defense responses. When the response of the plant is too weak or too late, a successful infection (compatible interaction) will result. A rapid and strong defense response (e. g. due to the presence of a resistance gene) will result in the resistant (incompatible) reaction. Defense responses include the production of toxic oxygen radicals and systemic signaling compounds as well as the activation of defense genes that lead to the production of structural barriers or other toxins. PMID:25272462

  3. Digestion of FMRFamide and nematode FMRFamide-like peptides (nematode FLPs) by the soluble fraction from Panagrellus redivivus homogenate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Proteases in the soluble fraction of homogenates prepared from the free-living nematode Panagrellus redivivus hydrolyzed the amidated invertebrate neuropeptides FMRFa and FLRFa, and nematode FMRFa-like peptides (FLPs) KPNFLRFa (FLP-1), APKPKFIRFa (FLP-5), KNEFIRFa (FLP-8), KPSFVRFa (FLP-9), RNKFEFIR...

  4. ACTIVITY OF FUNGAL CULTURE FILTRATES AGAINST SOYBEAN CYST NEMATODE AND ROOT-KNOT NEMATODE EGG HATCH AND JUVENILE MOTILITY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fungi were isolated from soybean cyst nematode (Heterodera glycines) eggs collected in China, and 253 isolates were assayed for production of compounds active against H. glycines and root-knot nematode (Meloidogyne incognita). Fungal isolates were grown for 3 and 7 days in potato dextrose broth (PD...

  5. SSR MARKER(S) ASSOCIATED WITH ROOT-KNOT NEMATODE RESISTANCE GENE(S) IN COTTON

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nematodes cause significant yield loss in US cotton, Gossypium hirsutum. Very few cotton lines are resistant to root-knot nematode [RKN] (Meloidogyne incognita spp.), one of the major nematode pest species in the US Cotton Belt. DNA markers for root-knot nematode resistance gene(s) will provide to...

  6. Microbial ecology and nematode control in natural ecosystems. Building coherence between microbial ecology and molecular mechanisms

    Microsoft Academic Search

    S. R. Costa; Putten van der W. H; B. R. Kerry

    2011-01-01

    Plant-parasitic nematodes have traditionally been studied in agricultural systems, where they can be pests of importance on a wide range of crops. Nevertheless, nematode ecology in natural ecosystems is receiving increasing interest because of the role of nematodes in soil food webs, nutrient cycling, influences on vegetation composition, and because of their indicator value. In natural ecosystems, plant-parasitic nematode populations

  7. Analysis of the transcriptome of the root lesion nematode Pratylenchus coffeae generated by 454 sequencing technology

    Microsoft Academic Search

    Annelies Haegeman; Soumi Joseph; Godelieve Gheysen

    2011-01-01

    To study interactions between plants and plant-parasitic nematodes, several omics studies have nowadays become extremely useful. Since most data available so far is derived from sedentary nematodes, we decided to improve the knowledge on migratory nematodes by studying the transcriptome of the nematode Pratylenchus coffeae through generating expressed sequence tags (ESTs) on a 454 sequencing platform.In this manuscript we present

  8. Nematode communities of Lake Tana and other inland water bodies of Ethiopia

    Microsoft Academic Search

    Eyualem Abebe; Jan Mees; August Coomans

    2001-01-01

    Free-living nematodes from littoral benthic sediments of four lakes, two rivers and a hot spring in Ethiopia are studied. Populations of nematodes encountered are identified to the species level. The general nematode (generic and species) composition of the lakes, rivers and hot spring are appraised by giving special emphasis to the nematodes from L. Tana, i.e. three sites where different

  9. Current Surveys of the Seroprevalence of Borrelia burgdorferi, Ehrlichia canis, Anaplasma phagocytophilum, Leishmania infantum, Babesia canis, Angiostrongylus vasorum and Dirofilaria immitis in Dogs in Bulgaria.

    PubMed

    Pantchev, Nikola; Schnyder, Manuela; Vrhovec, Majda Globokar; Schaper, Roland; Tsachev, Ilia

    2015-08-01

    Canine vector-borne diseases (CVBDs) have increasingly become a focus of interest in recent years. Some of the CVBDs are zoonotic and may therefore also represent a risk for the human population. Different factors are in discussion to explain the expansion of vectors and pathogens into formerly unaffected areas. Knowledge of the prevalence and distribution of CVBDs in Bulgaria is scant overall and most data rely on single case descriptions. The aim of the present study was to determine the seroprevalence of important CVBDs in 167 dogs from central-southern Bulgaria (Stara Zagora), with special emphasis on hitherto uninvestigated babesiosis and angiostrongylosis, on poorly investigated Lyme borreliosis and canine granulocytic anaplasmosis, and on the potentially zoonotic dirofilariosis and leishmaniosis. Relatively high prevalence rates were documented for anti-Babesia canis antibodies, Dirofilaria immitis antigen (16.2 %; 27/167 each), anti-Ehrlichia canis (21 %; 35/167) and anti-Anaplasma phagocytophilum antibodies (30.5 - 46.1 %; 51 - 77/167), while Borrelia burgdorferi seroprevalence was low (2.4 %; 4/167). All samples were negative for Leishmania infantum antibodies and Angiostrongylus vasorum antigen and antibodies. In total, 64.7 % (108/167) of the samples indicated infection or exposure to at least one agent and a high proportion of dual infections (39.8 %; 43/108) was demonstrated. Multiple infections with up to four different organisms were also detected. Our data underline the importance of CVBDs and especially of co-infections which could influence the clinical outcome in dogs. PMID:26152413

  10. Resistance of Grape Rootstocks to Plant-parasitic Nematodes.

    PubMed

    Ferris, H; Zheng, L; Walker, M A

    2012-12-01

    Candidate grape rootstocks were selected through a rigorous screening program initiated with important sources of resistance to Meloidogyne pathotypes and to Xiphinema index in Muscadinia rotundifolia and Vitis species native to North America. Based on their rooting capability and horticultural characteristics, 200 candidates were selected from 5,000 progeny of multiple crosses between commercial grape rootstocks and wild grape species that exhibited resistance to nematodes. After a 15-year screening process, 13 selections emerged with either almost complete or complete combined resistance to M. incognita Race 3, M. incognita pathotype Harmony C, M. arenaria pathotype Harmony A, and X. index, important nematode pests of grapevines. Durability of this broad resistance was tested by challenging the selections with the target nematodes in combination and with the target nematodes in combinations with species not included in the screening process. Durability of resistance of the candidate rootstocks was also tested by exposure to the nematode communities of infested field soils from different locations. Breadth of resistance was determined on the basis of their host status to non-target nematodes, including Mesocriconema xenoplax, Pratylenchus vulnus, Tylenchulus semipenetrans and Paratylenchus hamatus. After a total of 204 separate trials, the rootstocks were released to the grape industry as UCD GRN1, UCD GRN2, UCD GRN3, UCD GRN4, and UCD GRN5. We provide a compilation of current knowledge of the host status of these five newly released rootstocks and of 27 other rootstock cultivars to plant-parasitic nematodes. PMID:23482972

  11. Evolution of Parasitism in Insect-transmitted Plant Nematodes

    PubMed Central

    Giblin-Davis, R. M.; Davies, K. A.; Morris, K.; Thomas, W. K.

    2003-01-01

    Nematode-insect associations have evolved many times in the phylum Nematoda, but these lineages involve plant parasitism only in the Secernentean orders Aphelenchida and Tylenchida. In the Aphelenchida (Aphelenchoidoidea), Bursaphelenchus xylophilus (Pine wood nematode), B. cocophilus (Red ring or Coconut palm nematode) (Parasitaphelenchidae), and the many potential host-specific species of Schistonchus (fig nematodes) (Aphelenchoididae) nematode-insect interactions probably evolved independently from dauer-forming, mycophagous ancestors that were phoretically transmitted to breeding sites of their insect hosts in plants. Mycophagy probably gave rise to facultative or obligate plant-parasitism because of opportunities due to insect host switches or peculiarities in host behavior. In the Tylenchida, there is one significant radiation of insect-associated plant parasites involving Fergusobia nematodes (Fergusobiinae: Neotylenchidae) and Fergusonina (Fergusoninidae) flies as mutualists that gall myrtaceous plant buds or leaves. These dicyclic nematodes have different phases that are parasitic in either the insect or the plant hosts. The evolutionary origin of this association is unclear. PMID:19265987

  12. Leukotriene B4 amplifies eosinophil accumulation in response to nematodes

    PubMed Central

    Patnode, Michael L.; Bando, Jennifer K.; Krummel, Matthew F.; Locksley, Richard M.

    2014-01-01

    Eosinophil accumulation is a defining feature of the immune response to parasitic worm infection. Tissue-resident cells, such as epithelial cells, are thought to initiate eosinophil recruitment. However, direct recognition of worms by eosinophils has not been explored as a mechanism for amplifying eosinophil accumulation. Here, we report that eosinophils rapidly migrate toward diverse nematode species in three-dimensional culture. These include the mammalian parasite Nippostrongylus brasiliensis and the free-living nematode Caenorhabditis elegans. Surprisingly, collective migration toward worms requires paracrine leukotriene B4 signaling between eosinophils. In contrast, neutrophils show a minimal response to nematodes, yet are able to undergo robust leukotriene-dependent migration toward IgG-coated beads. We further demonstrate that eosinophils accumulate around C. elegans in the lungs of mice. This response is not dependent on bacterial products, CCR3, or complement activation. However, mice deficient in leukotriene signaling show markedly attenuated eosinophil accumulation after injection of C. elegans or N. brasiliensis. Our findings establish that nematode-derived signals can directly induce leukotriene production by eosinophils and that leukotriene signaling is a major contributor to nematode-induced eosinophil accumulation in the lung. The similarity of the eosinophil responses to diverse nematode species suggests that conserved features of nematodes are recognized during parasite infection. PMID:24889202

  13. Larval nematodes found in amphibians from northeastern Argentina.

    PubMed

    González, C E; Hamann, M I

    2010-11-01

    Five species of amphibians, Leptodactylus podicipinus, Scinax acuminatus, S. nasicus, Rhinella fernandezae and Pseudis paradoxa, were collected in Corrientes province, Argentina and searched for larval nematodes. All larval nematodes were found as cysts in the serous of the stomach of hosts. Were identified one superfamily, Seuratoidea; one genus, Spiroxys (Superfamily Gnathostomatoidea) and one family, Rhabdochonidae (Superfamily Thelazioidea). We present a description and illustrations of these taxa. These nematodes have an indirect life cycle and amphibians are infected by consuming invertebrate, the intermediate hosts. The genus Spiroxys and superfamily Seuratoidea were reported for the first time for Argentinean amphibians. PMID:21180919

  14. Effects of catechin polyphenols and preparations from the plant-parasitic nematode Heterodera glycines on protease activity and behavior in three nematode species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Protease activities in preparations from the plant-parasitic nematodes Heterodera glycines and Meloidogyne incognita and the free-living nematode Panagrellus redivivus were inhibited by exposure to a series of 8 catechin polyphenol analogs, (+)-catechin, (-)- epicatechin (EC), (-)-gallocatechin (GC)...

  15. The Effects of Root-knot Nematode Infection and Mi-mediated Nematode Resistance in Tomato on Plant Fitness

    PubMed Central

    Corbett, Brandon P.; Jia, Lingling; Sayler, Ronald J.; Arevalo-Soliz, Lirio Milenka

    2011-01-01

    The Mi-1.2 resistance gene in tomato (Solanum lycopersicum) confers resistance against several species of root-knot nematodes (Meloidogyne spp.). This study examined the impact of M. javanica on the reproductive fitness of near-isogenic tomato cultivars with and without Mi-1.2 under field and greenhouse conditions. Surprisingly, neither nematode inoculation or host plant resistance impacted the yield of mature fruits in field microplots (inoculum=8,000 eggs/plant), or fruit or seed production in a follow-up greenhouse bioassay conducted with a higher inoculum level (20,000 eggs/plant). However, under heavy nematode pressure (200,000 eggs/plant), greenhouse-grown plants carrying Mi-1.2 had more than ten-fold greater fruit production than susceptible plants and nearly forty-fold greater estimated lifetime seed production, confirming prior reports of the benefits of Mi-1.2. In all cases Mi-mediated resistance significantly reduced nematode reproduction. These results indicated that tomato can utilize tolerance mechanisms to compensate for moderate levels of nematode infection, but that the Mi-1.2 resistance gene confers a dramatic fitness benefit under heavy nematode pressure. No significant cost of resistance was detected in the absence of nematode infection. PMID:22791916

  16. SCREENING OF TRANSGENIC ANTHURIUMS FOR BACTERIAL BLIGHT AND NEMATODE RESISTANCE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthuriums exhibit limited resistance to bacterial blight caused by Xanthomonas axonopodis pv. dieffenbachiae and to the nematodes Radopholus simile and Meloidogyne javanica. Agrobacterium tumefaciens transformation of embryogenic calli with strains LBA4404, EHA105, and AGLO resulted in transgenic p...

  17. Soil Organic Matter and Management of Plant-Parasitic Nematodes

    PubMed Central

    Widmer, T. L.; Mitkowski, N. A.; Abawi, G. S.

    2002-01-01

    Organic matter and its replenishment has become a major component of soil health management programs. Many of the soil's physical, chemical, and biological properties are a function of organic matter content and quality. Adding organic matter to soil influences diverse and important biological activities. The diversity and number of free-living and plant-parasitic nematodes are altered by rotational crops, cover crops, green manures, and other sources of organic matter. Soil management programs should include the use of the proper organic materials to improve soil chemical, physical, and biological parameters and to suppress plant-parasitic nematodes and soilborne pathogens. It is critical to monitor the effects of organic matter additions on activities of major and minor plant-parasitic nematodes in the production system. This paper presents a general review of information in the literature on the effects of crop rotation, cover crops, and green manures on nematodes and their damage to economic crops. PMID:19265946

  18. Nematode parasites of waterfowl (Anseriformes) from western United States

    USGS Publications Warehouse

    McDonald, M.E.

    1974-01-01

    Thirty-four species of nematodes were found in 415 Anseriformes (Anatidae) of 27 species; 93.7% of birds over 4 weeks old were infected. Data on prevalence, host specificity, age of host, and geographic distribution are given. Infections were more intense in sick birds and birds in poor physical condition. Accidental or abnormal infection was more likely in sick than in normal birds. From 1 to 13 species of nematodes are reported from each host species, including 118 new host records, 3 nematodes new for North America, and 1 new species. Multiple infections were present in 76.5% of birds parasitized; eight species of nematodes were found in one whistling swan (Olor columbianus).

  19. PEST&CROP INDEX 2007 INSECTS, MITES & NEMATODES

    E-print Network

    Ginzel, Matthew

    , and Beetles ­ 13 What is That Gigantic Beetle - 16 Mexican Bean Beetle Millipede Expect the Unexpected When: Announcing New Website for Nematology ­ 12 Nematode Update ­ Should Corn Growers Be Alarmed About the New

  20. Ecological Biogeography of the Terrestrial Nematodes of Victoria Land, Antarctica

    PubMed Central

    Adams, Byron J.; Wall, Diana H.; Virginia, Ross A.; Broos, Emma; Knox, Matthew A.

    2014-01-01

    Abstract The terrestrial ecosystems of Victoria Land, Antarctica are characteristically simple in terms of biological diversity and ecological functioning. Nematodes are the most commonly encountered and abundant metazoans of Victoria Land soils, yet little is known of their diversity and distribution. Herein we present a summary of the geographic distribution, habitats and ecology of the terrestrial nematodes of Victoria Land from published and unpublished sources. All Victoria Land nematodes are endemic to Antarctica, and many are common and widely distributed at landscape scales. However, at smaller spatial scales, populations can have patchy distributions, with the presence or absence of each species strongly influenced by specific habitat requirements. As the frequency of nematode introductions to Antarctica increases, and soil habitats are altered in response to climate change, our current understanding of the environmental parameters associated with the biogeography of Antarctic nematofauna will be crucial to monitoring and possibly mitigating changes to these unique soil ecosystems. PMID:25061360

  1. Atypical Development in Plant and Soil Nematodes

    PubMed Central

    Ferris, Howard; Robbins, Robert; Yeates, Gregor

    2012-01-01

    Observations of atypical developmental and anatomical characteristics have been recorded for many taxa of soil nematodes. They include the unusual occurrence of extra feeding structures, aberrant configuration of features of both male and female reproductive systems, and the occurrence of intersexes assumed to be functionally female, functionally male, or non-functional. In many cases, hypotheses have been advanced regarding the genetic or developmental mechanisms and environmental stimuli that control, regulate, or facilitate abnormalities, but many are quite speculative and lack experimental verification. Further, the fitness costs or advantages, and the heritability of aberrant characters are largely unknown, except where they clearly preclude reproduction, either apomictic or amphimictic. Underlying mechanisms and ecological consequences may be difficult to study in organisms that are not readily cultured under axenic or sterile laboratory conditions, however information on developmental processes in Caenorhabditis elegans represents an important resource in which to seek homologies. PMID:23483848

  2. OX40 interactions in gastrointestinal nematode infection

    PubMed Central

    Ierna, Michelle X; Scales, Hannah E; Schwarz, Herbert; Bunce, Campbell; McIlgorm, Anne; Garside, Paul; Lawrence, Catherine E

    2006-01-01

    The immune expulsion of gastrointestinal nematode parasites is usually associated with T helper type 2 (Th2) responses, but the effector mechanisms directly responsible for parasite loss have not been elucidated. The intestinal inflammatory response accompanying infection with gastrointestinal helminths is thought to be a contributory factor leading to the expulsion of the parasite. However, we have shown that the intestinal inflammation, which is controlled by interleukin (IL)-4, is not required for parasite expulsion. OX40–OX40 ligand (L) signals have been shown to be important for the development of Th2 immune responses but are also involved in a number of inflammatory diseases including those of the intestine. Here, we have investigated the effect of OX40 and OX40L fusion protein treatment on the induction of protective Th2 responses and enteropathy following infection with the gastrointestinal nematode Trichinella spiralis. Treatment with an OX40–immunoglobulin (Ig) blocking fusion protein resulted in enhanced expulsion of the parasite and an increase in the accompanying mastocytosis, despite unaltered levels of Th2 cytokines. Furthermore, there was a delay in the villus atrophy and crypt hyperplasia usually associated with this infection. In contrast, levels of Th2 cytokines were greatly up-regulated in mice treated with an OX40L–Ig activating fusion protein, yet the expulsion of the parasite and the enteropathy were unaffected. Therefore, OX40 ligation potentiates the Th2 response without enhancing host protective immune responses, whereas blocking the OX40–OX40L interaction enhances host protection without promoting Th2 cytokine responses during Trichinella spiralis infection. PMID:16423046

  3. Utilization of Biological Control for Managing Plant-Parasitic Nematodes

    Microsoft Academic Search

    Patricia Timper

    \\u000a Biological control of plant-parasitic nematodes can be accomplished either by application of antagonistic organisms, conservation\\u000a and enhancement of indigenous antagonists, or a combination of both strategies. The application of biological control has\\u000a been inconsistent in suppressing nematode populations because the efficacy of antagonists is influenced by other soil organisms\\u000a and the host-plant. Integration of biological control with nematicides, solarization, organic

  4. A nematode effector protein similar to annexins in host plants

    Microsoft Academic Search

    Nrupali Patel; Noureddine Hamamouch; Chunying Li; Tarek Hewezi; Richard S. Hussey; Thomas J. Baum; Melissa G. Mitchum; Eric L. Davis

    2010-01-01

    Nematode parasitism genes encode secreted effector proteins that play a role in host infection. A homologue of the expressed Hg4F01 gene of the root-parasitic soybean cyst nematode, Heterodera glycines, encoding an annexin-like effector, was isolated in the related Heterodera schachtii to facilitate use of Arabidopsis thaliana as a model host. Hs4F01 and its protein product were exclusively expressed within the

  5. Nematodes from terrestrial and freshwater habitats in the Arctic

    PubMed Central

    2014-01-01

    Abstract We present an updated list of terrestrial and freshwater nematodes from all regions of the Arctic, for which records of properly identified nematode species are available: Svalbard, Jan Mayen, Iceland, Greenland, Nunavut, Northwest territories, Alaska, Lena River estuary, Taymyr and Severnaya Zemlya and Novaya Zemlya. The list includes 391 species belonging to 146 genera, 54 families and 10 orders of the phylum Nematoda. PMID:25197239

  6. Nematodes from terrestrial and freshwater habitats in the Arctic.

    PubMed

    Holovachov, Oleksandr

    2014-01-01

    WE PRESENT AN UPDATED LIST OF TERRESTRIAL AND FRESHWATER NEMATODES FROM ALL REGIONS OF THE ARCTIC, FOR WHICH RECORDS OF PROPERLY IDENTIFIED NEMATODE SPECIES ARE AVAILABLE: Svalbard, Jan Mayen, Iceland, Greenland, Nunavut, Northwest territories, Alaska, Lena River estuary, Taymyr and Severnaya Zemlya and Novaya Zemlya. The list includes 391 species belonging to 146 genera, 54 families and 10 orders of the phylum Nematoda. PMID:25197239

  7. Directional movement of entomopathogenic nematodes in response to electrical fields: Effects of species, magnitude of voltage, and infective juvenile age

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Entomopathogenic nematodes respond to a variety of stimuli when foraging. Previously, we reported a directional response to electrical fields for two entomopathogenic nematode species; specifically, when electrical fields were generated on agar plates Steinernema glaseri (a nematode that utilizes a...

  8. Low cryoprotectant concentrations and fast cooling for nematode cryostorage.

    PubMed

    Irdani, Tiziana; Scotto, Cristina; Roversi, Pio Federico

    2011-08-01

    Cryopreservation protocols based on slow freezing or vitrification often result in cell injury due to ice formation, cell dehydration and/or toxic concentrations of cryoprotectant (CPA). In this study, we present a cryopreservation technique based on low, non-toxic concentrations of cryoprotectants (? 2-4M) combined with a rapid cooling rate in the liquid nitrogen phase (-196°C). Protocols for successfully cryopreserving the plant parasitic nematodes Globodera tabacum tabacum, Heterodera schachtii and Meloidogyne incognita were developed, as demonstrated by the high survival rates and reproducibility of cyst and root-knot nematode species post-cryostorage. This approach for effective cryopreservation of viable plant-parasitic nematodes was developed by inducing an "apparent vitrification" by rapid cooling of the microscopic samples in less than 2M of cryoprotectant. The extremely thin structure (15-20 ?m width, 350-400 ?m length) of these nematodes, in combination with a direct and rapid exposure to LN(2), likely prevents the formation of damaging ice crystals. Moreover, this procedure results in viability of both short- and long-cryostorage samples. These techniques could potentially be used for the near-indefinite preservation of thousands of different nematode species. A cryo-nematode collection produced in our lab is available and presented here. PMID:21524646

  9. Diverse Host-Seeking Behaviors of Skin-Penetrating Nematodes

    PubMed Central

    Castelletto, Michelle L.; Gang, Spencer S.; Okubo, Ryo P.; Tselikova, Anastassia A.; Nolan, Thomas J.; Platzer, Edward G.; Lok, James B.; Hallem, Elissa A.

    2014-01-01

    Skin-penetrating parasitic nematodes infect approximately one billion people worldwide and are responsible for some of the most common neglected tropical diseases. The infective larvae of skin-penetrating nematodes are thought to search for hosts using sensory cues, yet their host-seeking behavior is poorly understood. We conducted an in-depth analysis of host seeking in the skin-penetrating human parasite Strongyloides stercoralis, and compared its behavior to that of other parasitic nematodes. We found that Str. stercoralis is highly mobile relative to other parasitic nematodes and uses a cruising strategy for finding hosts. Str. stercoralis shows robust attraction to a diverse array of human skin and sweat odorants, most of which are known mosquito attractants. Olfactory preferences of Str. stercoralis vary across life stages, suggesting a mechanism by which host seeking is limited to infective larvae. A comparison of odor-driven behavior in Str. stercoralis and six other nematode species revealed that parasite olfactory preferences reflect host specificity rather than phylogeny, suggesting an important role for olfaction in host selection. Our results may enable the development of new strategies for combating harmful nematode infections. PMID:25121736

  10. Soil sampling and isolation of entomopathogenic nematodes (Steinernematidae, Heterorhabditidae).

    PubMed

    Orozco, Rousel A; Lee, Ming-Min; Stock, S Patricia

    2014-01-01

    Entomopathogenic nematodes (a.k.a. EPN) represent a group of soil-inhabiting nematodes that parasitize a wide range of insects. These nematodes belong to two families: Steinernematidae and Heterorhabditidae. Until now, more than 70 species have been described in the Steinernematidae and there are about 20 species in the Heterorhabditidae. The nematodes have a mutualistic partnership with Enterobacteriaceae bacteria and together they act as a potent insecticidal complex that kills a wide range of insect species. Herein, we focus on the most common techniques considered for collecting EPN from soil. The second part of this presentation focuses on the insect-baiting technique, a widely used approach for the isolation of EPN from soil samples, and the modified White trap technique which is used for the recovery of these nematodes from infected insects. These methods and techniques are key steps for the successful establishment of EPN cultures in the laboratory and also form the basis for other bioassays that consider these nematodes as model organisms for research in other biological disciplines. The techniques shown in this presentation correspond to those performed and/or designed by members of S. P. Stock laboratory as well as those described by various authors. PMID:25046023

  11. Tomato transgenic plants expressing hairpin construct of a nematode protease gene conferred enhanced resistance to root-knot nematodes.

    PubMed

    Dutta, Tushar K; Papolu, Pradeep K; Banakar, Prakash; Choudhary, Divya; Sirohi, Anil; Rao, Uma

    2015-01-01

    Root-knot nematodes (Meloidogyne incognita) cause substantial yield losses in vegetables worldwide, and are difficult to manage. Continuous withdrawal of environmentally-harmful nematicides from the global market warrants the need for novel nematode management strategies. Utility of host-delivered RNAi has been demonstrated in several plants (Arabidopsis, tobacco, and soybean) that exhibited resistance against root-knot and cyst nematodes. Herein, a M. incognita-specific protease gene, cathepsin L cysteine proteinase (Mi-cpl-1), was targeted to generate tomato transgenic lines to evaluate the genetically modified nematode resistance. In vitro knockdown of Mi-cpl-1 gene led to the reduced attraction and penetration of M. incognita in tomato, suggesting the involvement of Mi-cpl-1 in nematode parasitism. Transgenic expression of the RNAi construct of Mi-cpl-1 gene resulted in 60-80% reduction in infection and multiplication of M. incognita in tomato. Evidence for in vitro and in vivo silencing of Mi-cpl-1 was confirmed by expression analysis using quantitative PCR. Our study demonstrates that Mi-cpl-1 plays crucial role during plant-nematode interaction and plant-mediated downregulation of this gene elicits detrimental effect on M. incognita development, reinforcing the potential of RNAi technology for management of phytonematodes in crop plants. PMID:25883594

  12. Pan-phylum Comparison of Nematode Metabolic Potential.

    PubMed

    Tyagi, Rahul; Rosa, Bruce A; Lewis, Warren G; Mitreva, Makedonka

    2015-05-01

    Nematodes are among the most important causative pathogens of neglected tropical diseases. The increased availability of genomic and transcriptomic data for many understudied nematode species provides a great opportunity to investigate different aspects of their biology. Increasingly, metabolic potential of pathogens is recognized as a critical determinant governing their development, growth and pathogenicity. Comparing metabolic potential among species with distinct trophic ecologies can provide insights on overall biology or molecular adaptations. Furthermore, ascertaining gene expression at pathway level can help in understanding metabolic dynamics over development. Comparison of biochemical pathways (or subpathways, i.e. pathway modules) among related species can also retrospectively indicate potential mistakes in gene-calling and functional annotation. We show with numerous illustrative case studies that comparisons at the level of pathway modules have the potential to uncover biological insights while remaining computationally tractable. Here, we reconstruct and compare metabolic modules found in the deduced proteomes of 13 nematodes and 10 non-nematode species (including hosts of the parasitic nematode species). We observed that the metabolic potential is, in general, concomitant with phylogenetic and/or ecological similarity. Varied metabolic strategies are required among the nematodes, with only 8 out of 51 pathway modules being completely conserved. Enzyme comparison based on topology of metabolic modules uncovered diversification between parasite and host that can potentially guide therapeutic intervention. Gene expression data from 4 nematode species were used to study metabolic dynamics over their life cycles. We report unexpected differential metabolism between immature and mature microfilariae of the human filarial parasite Brugia malayi. A set of genes potentially important for parasitism is also reported, based on an analysis of gene expression in C. elegans and the human hookworm Necator americanus. We illustrate how analyzing and comparing metabolism at the level of pathway modules can improve existing knowledge of nematode metabolic potential and can provide parasitism related insights. Our reconstruction and comparison of nematode metabolic pathways at a pan-phylum and inter-phylum level enabled determination of phylogenetic restrictions and differential expression of pathways. A visualization of our results is available at http://nematode.net and the program for identification of module completeness (modDFS) is freely available at SourceForge. The methods reported will help biologists to predict biochemical potential of any organism with available deduced proteome, to direct experiments and test hypotheses. PMID:26000881

  13. Phenotypic and molecular evaluation of cotton hairy roots as a model system for studying nematode resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cellular mechanisms that mediate resistance of allotetraploid cotton (Gossypium spp.) to root-knot nematode (Meloidogyne incognita) and reniform nematode (Rotylenchulus reniformis) are poorly understood. Here, Agrobacterium rhizogenes-induced hairy roots were investigated as a possible research...

  14. Potential of Neoactinolaimus as a biological control agent of root-knot and reniform nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The predatory nematode Neoactinolaimus spp. (family Actinolaimidae) was examined as a potential biological control agent against root-knot (Meloidogyne spp.) and reniform (Rotylenchulus reniformis) nematodes in laboratory conditions. Neoactinolaimus possesses a large odontostylet to puncture the cu...

  15. Incidence and influence of plant-parasitic nematodes in southern Illinois peach orchards

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The frequency, distribution and impact of plant-parasitic nematodes in southern Illinois peach orchards were determined. Nine plant parasitic nematode genera were detected comprising 11 different species: Helicotylenchus platyurus, Helicotylenchus pseudorobustus, Hoplolaimus spp., Meloidogyne spp., ...

  16. SURVEY OF STYLET BEARING NEMATODES ASSOCIATED WITH DATE PALM IN KHUZDAR DISTRICT, BALOCHISTAN, PAKISTAN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surveys were conducted during September and October 2002 to identify the stylet-bearing nematodes associated with date palm in Khuzdar district, Balochistan, Pakistan. The nematodes recorded were Tylenchus sp., Merlinius sp., Helicotylenchus indicus, Psilenchus hilarulus, Aphelenchoides sp., Meloido...

  17. BACTERIAL PREFERENCES OF THE BACTERIVOROUS SOIL NEMATODE CEPHALOBUS BREVICAUDA (CEPHALOBIDATE): EFFECT OF BACTERIAL TYPE AND SIZE

    EPA Science Inventory

    Cell size and type may affect availability of bacteria for consumption by bacterivorous nematodes in the soil and in culture. This study explored the bacterial preferences of the bacterivorous soil nematode Cephalobus brevicauda (Cephalobidae) by comparing bactgeria isolated dir...

  18. Taxonomy, morphology and phylogenetics of coffee-associated root-lesion nematodes, Pratylenchus spp

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Technical Abstract: Although lesion nematodes (Pratylenchus species) can reduce coffee yield worldwide, methods for their identification are often difficult to implement. This review summarizes the diagnostic morphological features for distinguishing the eight previously described lesion nematode sp...

  19. [Intestinal nematodes of the Aythyini ducks in Western Pomerania].

    PubMed

    Kavetska, Katarzyna M

    2005-01-01

    Intestinal nematodes of the Aythyini ducks in Western Pomerania. Biology, including ecology, of the Aythyini renders them particularly attractive subjects of parasitological studies. The tribe is represented in Poland by 4 nesting species; two of them, Aythya fuligula and A. ferina, are very abundant game birds. However, their helminth fauna, including nematodes, is still very poorly known. This study was aimed at quantifying the structure of parasitic intestinal nematodes of the Western Pomeranian Aythyini. The study, performed in 1999-2004, involved a total of 71 ducks representing 3 species: A. ferina, A. fuligula, and A. marila. The nematodes, isolated from the intestines, were fixed in 75% ethyl alcohol and cleared in lactic acid. Among the 9668 helminth individuals found, 589 (6.1%) represented the phylum Nematoda. They were found in 57 ducks (80.3% of all the ducks examined). The nematodes belonged to the following 4 families: Amidostomatidae, Tetrameridae, Acuariidae, and Trichuridae. They were identified as representing 8 species, 2 genera (Amidostomoides sp. and Tetrameres sp.), and 1 subfamily (Capillariinae gen. sp.); in addition, 1 damaged individual could be identified as a nematode only. The highest prevalence (57.8%), at mean intensity (4.8 inds), was typical of Amidostomoides petrovi (Shakhtahtinskaya, 1956) Lomakin, 1991, while Tetrameres fissispina (Diesing, 1861) Travassos, 1914 occurred with the highest intensity (15.1 inds) and 12.7% prevalence. Nematodes of the subfamily Capillariinae occurred with a fairly high intensity (averaging 10.0 inds) as well, although their prevalence was not high, either (4.2% of all ducks were infected). The nematofauna studied was clearly dominated by A. petrovi, T. fissispina, and Capillaria anatis (Schrank, 1790). The total frequency of occurrence of those species was close to 80%; their dominance indices exceeded the threshold value of 0.1 and amounted to 1.6 (the dominant A. petrovi), 0.2, and 0.5 (the subdominants T. fissispina and C. anatis, respectively). The three species listed occurred with the highest mean density (2.8; 1.9; and 1.8 nematode per duck examined). No age- (adult vs. immature) or sex- (males vs. females) related differences in the quantitative structure of the parasitic Aythyini nematodes were observed. PMID:16838626

  20. The dual effects of root-cap exudates on nematodes: from quiescence in plant-parasitic nematodes to frenzy in entomopathogenic nematodes

    PubMed Central

    Hiltpold, Ivan; Jaffuel, Geoffrey; Turlings, Ted C. J.

    2015-01-01

    To defend themselves against herbivores and pathogens, plants produce numerous secondary metabolites, either constitutively or de novo in response to attacks. An intriguing constitutive example is the exudate produced by certain root-cap cells that can induce a state of reversible quiescence in plant-parasitic nematodes, thereby providing protection against these antagonists. The effect of such root exudates on beneficial entomopathogenic nematodes (EPNs) remains unclear, but could potentially impair their use in pest management programmes. We therefore tested how the exudates secreted by green pea (Pisum sativum) root caps affect four commercial EPN species. The exudates induced reversible quiescence in all EPN species tested. Quiescence levels varied with the green pea cultivars tested. Notably, after storage in root exudate, EPN performance traits were maintained over time, whereas performances of EPNs stored in water rapidly declined. In sharp contrast to high concentrations, lower concentrations of the exudate resulted in a significant increase in EPN activity and infectiousness, but still reduced the activity of two plant-parasitic nematode species. Our study suggests a finely tuned dual bioactivity of the exudate from green pea root caps. Appropriately formulated, it can favour long-term storage of EPNs and boost their infectiousness, while it may also be used to protect plants from plant-parasitic nematodes. PMID:25165149

  1. Enzymology of the nematode cuticle: A potential drug target?

    PubMed Central

    Page, Antony P.; Stepek, Gillian; Winter, Alan D.; Pertab, David

    2014-01-01

    All nematodes possess an external structure known as the cuticle, which is crucial for their development and survival. This structure is composed primarily of collagen, which is secreted from the underlying hypodermal cells. Extensive studies using the free-living nematode Caenorhabditis elegans demonstrate that formation of the cuticle requires the activity of an extensive range of enzymes. Enzymes are required both pre-secretion, for synthesis of component proteins such as collagen, and post-secretion, for removal of the previous developmental stage cuticle, in a process known as moulting or exsheathment. The excretion/secretion products of numerous parasitic nematodes contain metallo-, serine and cysteine proteases, and these proteases are conserved across the nematode phylum and many are involved in the moulting/exsheathment process. This review highlights the enzymes required for cuticle formation, with a focus on the post-secretion moulting events. Where orthologues of the C. elegans enzymes have been identified in parasitic nematodes these may represent novel candidate targets for future drug/vaccine development. PMID:25057463

  2. Sequential Decision Rules for Managing Nematodes with Crop Rotations

    PubMed Central

    Burt, O. R.; Ferris, H.

    1996-01-01

    A dynamic model of nematode populations under a crop rotation that includes both host and nonhost crops is developed and used to conceptualize the problem of economic control. The steady state of the dynamic system is used to devise an approximately optimal decision policy, which is then applied to cyst nematode (Heterodera schachtii) control in a rotation of sugarbeet with nonhost crops. Long-run economic returns from this approximately optimal decision rule are compared with results from solution of the exact dynamic optimization model. The simple decision rule based on the steady state provides long-run average returns that are similar to the fully optimal solution. For sugarbeet and H. schachtii, the simplified rule can be calculated by maximizing a relatively simple algebraic expression with respect to the number of years in the sequence of nonhost crops. Maximization is easy because only integers are of interest and the number of years in nonhost crops is typically small. Solution of this problem indirectly yields an approximation to the optimal dynamic economic threshold density of nematodes in the soil. The decision rule requires knowledge of annual nematode population change under host and nonhost crops, and the relationship between crop yield and nematode population density. PMID:19277164

  3. EXAMINATION OF RHIZOSPHERE-ASSOCIATED MICROBES FOR PRODUCTION OF COMPOUNDS ACTIVE AGAINST PLANT-PARASITIC NEMATODES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In vitro studies identified fungi and bacteria that produce compounds active against plant-parasitic nematodes. Assays of fungus culture filtrates were conducted with Heterodera glycines (soybean cyst nematode: SCN) and Meloidogyne incognita (root-knot nematode: RKN). The tested filtrates exhibite...

  4. Dispersal patterns and behaviour of the nematode Phasmarhabditis hermaphrodita in mineral soils and organic media

    Microsoft Academic Search

    Keith MacMillan; Solveig Haukeland; Robbie Rae; Iain Young; John Crawford; Simona Hapca; Michael Wilson

    2009-01-01

    The commercially available parasitic nematode Phasmarhabditis hermaphrodita is an effective biocontrol agent for slugs and particularly Deroceras reticulatum, a widespread pest species. Use of the nematode is currently limited by cost and it may be that by developing a fuller understanding of the ecology and behaviour of this nematode, more cost effective application strategies can be developed. We investigated the

  5. Transcript analysis of sedentary female reniform nematodes identifies potential targets ofr RNAi-mediated resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    RNA-interference (RNAi) has become an attractive avenue of research in the development of crop resistance to sedentary plant-parasitic nematodes. A prerequisite for this type of research is the availability of high quality gene sequence data for the nematode in question. The reniform nematode (Rot...

  6. 78 FR 27856 - Golden Nematode; Removal of Regulated Areas in Livingston and Steuben Counties, NY

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-13

    ...Docket No. APHIS-2012-0079] Golden Nematode; Removal of Regulated Areas in Livingston...interim rule that amended the golden nematode regulations by removing areas in Livingston...these two counties are free of golden nematode, and we determined that regulation...

  7. Sensitive and reliable detection of grapevine fanleaf virus in a single Xiphinema index nematode vector

    Microsoft Academic Search

    Gérard Demangeat; Véronique Komar; Pascal Cornuet; Daniel Esmenjaud; Marc Fuchs

    2004-01-01

    Grapevine fanleaf virus (GFLV) is specifically transmitted from plant to plant by the ectoparasitic nematode Xiphinema index. A sensitive and reliable procedure was developed to readily detect GFLV in a single viruliferous X. index, regardless of the nematode origin, i.e. greenhouse rearings or vineyard soils. The assay is based on bead milling to disrupt nematodes extracted from soil samples, solid-phase

  8. EFFECTS OF COVER CROPPING, SOLARIZATION, AND SOIL FUMIGATION ON NEMATODE COMMUNITIES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While free-living nematodes play important roles in soil nutrient cycling, many pre-plant soil practices act as perturbations to nematode communities. A two-year field experiment was conducted to examine nematode communities in soil treated with methyl bromide (MB) fumigation, solarization (S) for 6...

  9. Molecular and morphological characterization of the corn cyst nematode, Heterodera zeae, from Greece

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The corn cyst nematode Heterodera zeae was first detected in India, where it has wide distribution. This nematode has also been reported from Pakistan, Egypt, Thailand, Nepal, the United States, and Portugal. There is limited information regarding nematodes attacking cereals in Greece, and thus far ...

  10. Genome sequence of the metazoan plant-parasitic nematode Meloidogyne incognita

    Microsoft Academic Search

    Jérôme Gouzy; Jean-Marc Aury; Philippe Castagnone-Sereno; Etienne G J Danchin; Emeline Deleury; Laetitia Perfus-Barbeoch; Véronique Anthouard; François Artiguenave; Vivian C Blok; Marie-Cécile Caillaud; Pedro M Coutinho; Corinne Dasilva; Francesca De Luca; Florence Deau; Magali Esquibet; Timothé Flutre; Jared V Goldstone; Noureddine Hamamouch; Tarek Hewezi; Olivier Jaillon; Claire Jubin; Paola Leonetti; Marc Magliano; Tom R Maier; Gabriel V Markov; Paul McVeigh; Graziano Pesole; Julie Poulain; Marc Robinson-Rechavi; Erika Sallet; Béatrice Ségurens; Delphine Steinbach; Tom Tytgat; Edgardo Ugarte; Cyril van Ghelder; Pasqua Veronico; Thomas J Baum; Mark Blaxter; Teresa Bleve-Zacheo; Eric L Davis; Jonathan J Ewbank; Bruno Favery; Eric Grenier; Bernard Henrissat; John T Jones; Vincent Laudet; Aaron G Maule; Hadi Quesneville; Marie-Noëlle Rosso; Thomas Schiex; Geert Smant; Jean Weissenbach; Patrick Wincker; Pierre Abad

    2008-01-01

    Plant-parasitic nematodes are major agricultural pests worldwide and novel approaches to control them are sorely needed. We report the draft genome sequence of the root-knot nematode Meloidogyne incognita, a biotrophic parasite of many crops, including tomato, cotton and coffee. Most of the assembled sequence of this asexually reproducing nematode, totaling 86 Mb, exists in pairs of homologous but divergent segments.

  11. Transcript analysis of parasitic females of the sedentary semi-endoparasitic nematode Rotylenchulus reniformis

    Microsoft Academic Search

    Martin J. Wubben; Franklin E. Callahan; Brian S. Scheffler

    2010-01-01

    Rotylenchulus reniformis, the reniform nematode, is a sedentary semi-endoparasitic nematode capable of infecting >300 plant species, including a large number of crops such as cotton, soybean, and pineapple. In contrast to other economically important plant-parasitic nematodes, molecular genetic data regarding the R. reniformis transcriptome is virtually nonexistant. Herein, we present a survey of R. reniformis ESTs that were sequenced from

  12. (Homo)glutathione Deficiency Impairs Root-knot Nematode Development in Medicago truncatula

    Microsoft Academic Search

    Fabien Baldacci-Cresp; Christine Chang; Mickaël Maucourt; Catherine Deborde; Julie Hopkins; Philippe Lecomte; Stéphane Bernillon; Renaud Brouquisse; Annick Moing; Pierre Abad; Didier Hérouart; Alain Puppo; Bruno Favery; Pierre Frendo

    2012-01-01

    Root-knot nematodes (RKN) are obligatory plant parasitic worms that establish and maintain an intimate relationship with their host plants. During a compatible interaction, RKN induce the redifferentiation of root cells into multinucleate and hypertrophied giant cells essential for nematode growth and reproduction. These metabolically active feeding cells constitute the exclusive source of nutrients for the nematode. Detailed analysis of glutathione

  13. Desiccation survival in an Antarctic nematode: molecular analysis using expressed sequenced tags

    Microsoft Academic Search

    Bishwo N Adhikari; Diana H Wall; Byron J Adams

    2009-01-01

    BACKGROUND: Nematodes are the dominant soil animals in Antarctic Dry Valleys and are capable of surviving desiccation and freezing in an anhydrobiotic state. Genes induced by desiccation stress have been successfully enumerated in nematodes; however we have little knowledge of gene regulation by Antarctic nematodes which can survive multiple environmental stresses. To address this problem we investigated the genetic responses

  14. Association of Pine Wood Nematode with Stressed Trees in Minnesota, Iowa, and Wisconsin

    E-print Network

    Association of Pine Wood Nematode with Stressed Trees in Minnesota, Iowa, and Wisconsin M. J. 1982. Association of pine wood nematode with stressed trees in Minnesota, Iowa, and Wisconsin. Plant Disease 66:934- 937. Trees infected with the pine wood nematode BursapheJenchus xylophiJusin Minnesota

  15. THE POTENTIAL FOR MAPPING NEMATODE DISTRIBUTIONS FOR SITE-SPECIFIC MANAGEMENT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The success of site-specific nematode management depends on a grower or advisor being able to afford to make a map of an infestation that is accurate enough for management decisions. The spatial dependence of nematode infestations and correlation of soil attributes with nematode density were assess...

  16. Development of a PCR-based Molecular Marker to Select for Nematode Resistance in Peanut

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The peanut root-knot nematode (Meloidogyne arenaria (Neal) Chitwood race 1) is a significant pathogen on peanut (Arachis hypogaea L.). Nematode-resistant cultivars would reduce yield losses while reducing the use of nematicides in fields where these nematodes occur. Through years of breeding effor...

  17. Regulatory interplay between soybean root and soybean cyst nematode during a resistant and susceptible reaction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Plant parasitic nematodes (PPNs) are obligate parasites that feed on the roots of living host plants. Often, these nematodes can lay hundreds of eggs, each capable of surviving in the soil for as long as 12 years. When it comes to wreaking havoc on agricultural yield, few nematodes can c...

  18. Heterorhabditidoides chongmingensis gen. nov., sp. nov. (Rhabditida: Rhabditidae), a novel member of the entomopathogenic nematodes

    Microsoft Academic Search

    Chongxing Zhang; Jingrui Liu; Mingxu Xu; Jie Sun; Shouyun Yang; Xianhui An; Guofu Gao; Maosong Lin; Ren Lai; Ziyi He; Yidong Wu; Keyun Zhang

    2008-01-01

    During a recent soil sample survey in Eastern China, a new entomopathogenic nematode species, collected from the Chongming Islands in the southern–eastern area of Shanghai, was discovered. Morphological characteristics of different developmental stages of the nematode combined with molecular data showed that this nematode is a new genus of Rhabditidae, and described as Heterorhabditidoides chongmingensis gen. nov., sp. nov., for

  19. Natural occurrence of entomogenous nematodes in tennessee nursery soils.

    PubMed

    Rueda, L M; Osawaru, S O; Georgi, L L; Harrison, R E

    1993-06-01

    To isolate potential insect biocontrol agents, entomogenous nematodes were surveyed in Tennessee plant nurseries in 1991. Soil samples from 113 nursery sites were baited with greater wax moth (Galleria mellonella) larvae, house cricket (Acheta domesticus) adults, lesser mealworm (Alphitobius diaperings) adults, and house fly (Musca domestica) larvae. Heterorhabditis bacteriophora and Steinernema carpocapsae were each recovered from 17 soil samples. Heterorhabditis bacteriophora was more common in habitats with crape myrtle (Lagerstroemia indica) and Chinese juniper (Juniperus chinensis) than other nursery plants, and S. carpocapsae was more frequently recovered from habitats with juniper and Southern magnolia (Magnolia grandiflora). Bulk density, electrical conductivity, organic matter, pH, temperature, and moisture content of the entomogenous-nematode positive soil samples were compared. Other nematode genera recovered with insect baits included Rhabditis sp., Pelodera sp., Cryptaphelenchoides sp., and Mesodiplogaster sp., which was recovered from a greater percentage of soil samples than the other five genera. PMID:19279756

  20. Natural Occurrence of Entomogenous Nematodes in Tennessee Nursery Soils

    PubMed Central

    Rueda, L. M.; Osawaru, S. O.; Georgi, L. L.; Harrison, R. E.

    1993-01-01

    To isolate potential insect biocontrol agents, entomogenous nematodes were surveyed in Tennessee plant nurseries in 1991. Soil samples from 113 nursery sites were baited with greater wax moth (Galleria mellonella) larvae, house cricket (Acheta domesticus) adults, lesser mealworm (Alphitobius diaperings) adults, and house fly (Musca domestica) larvae. Heterorhabditis bacteriophora and Steinernema carpocapsae were each recovered from 17 soil samples. Heterorhabditis bacteriophora was more common in habitats with crape myrtle (Lagerstroemia indica) and Chinese juniper (Juniperus chinensis) than other nursery plants, and S. carpocapsae was more frequently recovered from habitats with juniper and Southern magnolia (Magnolia grandiflora). Bulk density, electrical conductivity, organic matter, pH, temperature, and moisture content of the entomogenous-nematode positive soil samples were compared. Other nematode genera recovered with insect baits included Rhabditis sp., Pelodera sp., Cryptaphelenchoides sp., and Mesodiplogaster sp., which was recovered from a greater percentage of soil samples than the other five genera. PMID:19279756

  1. Sampling for Regional Monitoring of Nematode Communities in Agricultural Soils

    PubMed Central

    Neher, D. A.; Campbell, C. L.

    1996-01-01

    Regional assessment of nematode communities to monitor the condition or ecological health of agricultural soils requires sampling programs with measures of known reliability and the ability to detect differences over time. Numbers of fields sampled in a region, samples taken per field, and subsamples assayed per sample must be balanced with cost to provide the best sampling scheme. We used components of variance from statewide surveys in North Carolina (1992) and Nebraska (1993) to estimate number of (i) fields to be sampled; (ii) 20-core, composite soil samples to be obtained for each field; and (iii) subsamples to be assayed for each composite sample to detect a specified amount of change in index values within a geographic region. Variances for these three components were used to estimate the degree of reliability for five ecologically based indices (four measures of maturity and one of diversity) of nematode communities. Total variance for maturity and diversity indices, based upon communities of free-living nematodes, was greater in North Carolina than in Nebraska; the opposite was true for indices based strictly upon maturity of communities of plant-parasitic nematodes or of all nematodes in soil. Variability within samples was greater in North Carolina than in Nebraska, especially for maturity indices based only upon free-living nematodes. We identified two possible sampling strategies for a regional survey: Option 1, with two independent samples per field and a single subsample assayed per sample, which would provide a reliability ratio value ?0.6 for most indices; and Option 2, with three independent samples per field and two subsamples assayed per sample, which would provide a reliability ratio value ?0.7 for several indices. When cost was considered, Option 1 was the better strategy. Number of fields to be sampled within a region or state varied with the index chosen; with specific indices, however, a 10% change in mean index value could be detected with a sample of 50 to 100 fields. PMID:19277135

  2. Navigation and chemotaxis of nematodes in bulk and confined fluids

    NASA Astrophysics Data System (ADS)

    Bilbao, Alejandro; Padmanabhan, Venkat; Rumbaugh, Kendra; Vanapalli, Siva; Blawzdziewicz, Jerzy

    2013-03-01

    Small nematodes, such as the model organism C. elegans, propel themselves by producing sinuous undulations along the body and perform turns by varying the undulation amplitude. We have recently demonstrated [PLoS ONE 7(7) e40121 (2012)] that such motions can be accurately represented in terms of a piecewise-harmonic body curvature. We combine our harmonic-curvature description with highly accurate hydrodynamic bead-chain models to investigate the swimming efficiency and turning capabilities of the worm in bulk and confined fluids. Our results indicate that for the same change of the curvature-wave amplitude, a swimming nematode turns by a smaller angle compared to a crawling worm. The difference is due to rotational slip with respect to the surrounding medium, but the angles are sufficiently large to allow for efficient turning maneuvers. We use our description of nematode maneuverability to study chemotaxis in both confined and unconfined fluids. Small nematodes, such as the model organism C. elegans, propel themselves by producing sinuous undulations along the body and perform turns by varying the undulation amplitude. We have recently demonstrated [PLoS ONE 7(7) e40121 (2012)] that such motions can be accurately represented in terms of a piecewise-harmonic body curvature. We combine our harmonic-curvature description with highly accurate hydrodynamic bead-chain models to investigate the swimming efficiency and turning capabilities of the worm in bulk and confined fluids. Our results indicate that for the same change of the curvature-wave amplitude, a swimming nematode turns by a smaller angle compared to a crawling worm. The difference is due to rotational slip with respect to the surrounding medium, but the angles are sufficiently large to allow for efficient turning maneuvers. We use our description of nematode maneuverability to study chemotaxis in both confined and unconfined fluids. This work was supported by NSF grant No. CBET 1059745.

  3. Investigating the role of HSP90 in the growth and development of free-living and plant parasitic nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant parasitic nematodes cause in excess of $100 billion of global crop losses each year. Cyst nematodes (Heterodera spp.) are endoparasitic root-feeding nematodes, and the soybean cyst nematode (SCN), Heterodera glycines, causes substantial losses in soybean yield in the U.S.A. as well as througho...

  4. Statistical and Economic Techniques for Site-specific Nematode Management.

    PubMed

    Liu, Zheng; Griffin, Terry; Kirkpatrick, Terrence L

    2014-03-01

    Recent advances in precision agriculture technologies and spatial statistics allow realistic, site-specific estimation of nematode damage to field crops and provide a platform for the site-specific delivery of nematicides within individual fields. This paper reviews the spatial statistical techniques that model correlations among neighboring observations and develop a spatial economic analysis to determine the potential of site-specific nematicide application. The spatial econometric methodology applied in the context of site-specific crop yield response contributes to closing the gap between data analysis and realistic site-specific nematicide recommendations and helps to provide a practical method of site-specifically controlling nematodes. PMID:24643451

  5. [Effect of the soil contamination with a potato cyst-forming nematode on the community structure of soil-inhabiting nematodes].

    PubMed

    Gruzdeva, L I; Suzhchuk, A A

    2008-01-01

    Nematode community structure of the potato fields with different infection levels of potato cyst-forming nematode (PCN) such as 10, 30 and 214 cysts per 100 g of soil has been investigated. The influence of specialized parasite on nematode fauna and dominance character of different ecological-trophic groups were described. Parasitic nematode genera in natural meadow biocenosis and agrocenoses without PCN are Paratylenchus, Tylenchorhynchus, and Helicotylenchus. It is established, that Paratylenchus nanus was the prevalent species among plant parasites at low infection level. Larvae of Globodera prevailed in the soil with middle and high infection levels and substituted individuals of other genera of parasitic nematodes. The fact of increase in number of hyphal-feeding nematode Aphelenchus avenae was revealed. PMID:19198175

  6. Comparative genetics and genomics of nematodes: genome structure, development, and lifestyle.

    PubMed

    Sommer, Ralf J; Streit, Adrian

    2011-01-01

    Nematodes are found in virtually all habitats on earth. Many of them are parasites of plants and animals, including humans. The free-living nematode, Caenorhabditis elegans, is one of the genetically best-studied model organisms and was the first metazoan whose genome was fully sequenced. In recent years, the draft genome sequences of another six nematodes representing four of the five major clades of nematodes were published. Compared to mammalian genomes, all these genomes are very small. Nevertheless, they contain almost the same number of genes as the human genome. Nematodes are therefore a very attractive system for comparative genetic and genomic studies, with C. elegans as an excellent baseline. Here, we review the efforts that were made to extend genetic analysis to nematodes other than C. elegans, and we compare the seven available nematode genomes. One of the most striking findings is the unexpectedly high incidence of gene acquisition through horizontal gene transfer (HGT). PMID:21721943

  7. Diversity and prevalence of metastrongyloid nematodes infecting the red panda (Ailurus fulgens) in European zoos.

    PubMed

    Bertelsen, Mads F; Meyland-Smith, Frederik; Willesen, Jakob L; Jefferies, Ryan; Morgan, Eric R; Monrad, Jesper

    2010-09-20

    Metastrongyloid induced pneumonia has been described sporadically in the red panda (Ailurus fulgens). Early descriptions in pandas recently imported to the USA from China involved parasites morphologically similar to Angiostrongylus spp. and Crenosomatidae. More recently, four cases of severe verminous pneumonia associated with Angiostrongylus vasorum have been reported from European zoos. A coprological survey of the red panda population within European zoos was conducted in 2008. Faecal samples from 115 pandas originating from 54 zoos were collected on 3 consecutive days. Using Baermann technique, 40 animals (35%) from 20 zoos (37%) were found to shed metastrongyloid first stage larvae (L(1)). Based on their morphology and size, the L(1) observed could be divided into three morphologically distinct types: (1) a Crenosoma sp. type (n=5, overall prevalence: 4.3%), (2) an A. vasorum type (n=3, 2.6%), and (3) an unidentified metastrongyloid species, similar to, but morphologically distinct from A. vasorum (n=32, 27.8%). Further confirmation of species identification was provided by PCR amplification and sequencing of the 18S rRNA gene, which confirmed three different species. The novel Crenosoma species was most genetically analogous to Crenosoma mephitidis and the unidentified metastrongyloid species was most similar to Stenurus minor and Torynurus convulutus. Routine and quarantine health care of red pandas in captivity should take account of the risk of Angiostrongylus and Crenosoma infection in endemic areas, but should also be cognisant of the widespread presence of an apparently less pathogenic species of lungworm. The identity of the two potentially novel species is subject to further work. PMID:20570049

  8. Grazing sericea lespedeza for control of gastrointestinal nematodes in lambs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alternatives to chemical dewormers are needed to counter anthelmintic resistance and improve organic management systems. The objective was to examine the effectiveness of grazing sericea lespedeza (SL) compared with grass pastures for control of gastrointestinal nematodes (GIN) in lambs. In Experi...

  9. Evaluation of some Vulval Appendages in Nematode Taxonomy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A survey of the nature and phylogenetic distribution of nematode vulval appendages revealed three major classes based on composition, position and orientation: membranes, flaps, and epiptygma. Minor classes included cuticular inflations, vulval tubes of extruded gonadal tissues, vulval ridges, and p...

  10. Amphiregulin-a Th2 cytokine enhancing resistance to nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Intestinal nematode infections remain a major health threat to humans despite improved sanitation. Protection is mainly mediated by Type 2-biased immune responses, characterized by Th2 lymphocytes and other cells secreting a set of cytokines including Interleukin 4 (IL-4), IL-5, IL-10, and IL-13. I...

  11. ENTOMOPATHOGENIC NEMATODES AND INSECTS: DIRECT AND ACTIVE INFECTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In nature, entomopathogenic nematodes (Steinernematidae and Heterorhabditidae) must infect an insect host in order to complete their life cycle. The decision to infect or not is critical because once inside the host there is no turning back. Here, we review and analyze infection behavior of entomo...

  12. Nematode suppression by endophyte-associated tall fescue

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tall fescue is planted as a forage and turf grass and a postplant ground cover for reducing soil erosion. It withstands drought and is resistant to various pests, including some plant-parasitic nematodes. The presence of the endophytic fungus Neotyphodium coenophialum can increase tall fescue grow...

  13. Herbal dewormer fails to control gastrointestinal nematodes in goats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gastrointestinal nematode (GIN) parasitism is the most important disease of small ruminants. Control is usually based on the use of chemical anthelmintics (dewormers); but these are prohibited from use in organic livestock, and the effectiveness of chemical anthelmintics in conventional operations ...

  14. ROOT-KNOT NEMATODE RESISTANCE IN AFRICAN PEARL MILLETS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resistance to Meloidogyne incognita in pearl millet reduces nematode populations that can damage crops grown in rotations. Pearl millets from Africa were evaluated as sources of resistance. Seventeen pearl millets were evaluated as bulk (S0) populations. All African varieties expressed some level o...

  15. Fatal Human Meningoencephalitis due to Halicephalobus Nematodes, Germany.

    PubMed

    Monoranu, Camelia-Maria; Müllges, Wolfgang; Keppler, Marc; Brehm, Klaus; Ondrejka, Sarah L; Muntau, Birgit; Tannich, Egbert; Müller-Hermelink, Hans Konrad; Tappe, Dennis

    2015-04-01

    Infections with Halicephalobus nematodes, causative agents of severe meningoencephalitis in horses, have rarely been reported in humans. In this study, the clinical, serological, cytokine, and histopathological findings of a rapidly progressive and eventually fatal meningoencephalitis in a previously healthy human are described. The helminth was finally diagnosed by specific polymerase chain reactions from post mortem tissue. PMID:26125032

  16. Radiation Effects on Nematodes: Results from IML-1 Esperiments

    NASA Technical Reports Server (NTRS)

    Nelson, G. A.; Schubert, W. W.; Kazarians, G. A.; Righards, G. F.; Benton, E. V; Benton, E. R.; Henke, R.

    1993-01-01

    The nematode Caenorhabditis elegans was exposed to natural space radiation using the ESA Biorack facility aboard Spacelab on International Microgravity Laboratory 1, STS-42. For the major experimental objective dormant animals were suspended in buffer or on agar or immobilized next to CR-39 plactic nuclear track detectors to correlate fluence of HZE particles with genetic events.

  17. Detection of gastrointestinal nematodes by a coproantigen capture ELISA

    Microsoft Academic Search

    G. C Coles

    1996-01-01

    An assay is described for the quantitative detection of excretory\\/secretory antigens liberated by the intestinal nematode Heligmosomoides polygyrus and voided in the host's faeces. A rabbit polyclonal antiserum to the antigens detected them in a dose-dependent manner and was sufficiently sensitive to recognise infection in mice carrying a mean worm burden of nine worms. The assay was specific, giving higher

  18. Polymorphic segmental duplication in the nematode Caenorhabditis elegans

    Microsoft Academic Search

    Ismael A Vergara; Allan K Mah; Jim C Huang; Maja Tarailo-Graovac; Robert C Johnsen; David L Baillie; Nansheng Chen

    2009-01-01

    BACKGROUND: The nematode Caenorhabditis elegans was the first multicellular organism to have its genome fully sequenced. Over the last 10 years since the original publication in 1998, the C. elegans genome has been scrutinized and the last gaps were filled in November 2002, which present a unique opportunity for examining genome-wide segmental duplications. RESULTS: Here, we performed analysis of the

  19. UDP-Galactopyranose Mutase in Nematodes Darryl A. Wesener,

    E-print Network

    Kiessling, Laura

    monosaccharide residue present in the glycoconjugates of several human pathogens is galactofur- anose (Galf). This five-membered ring isomer of galactose has not been detected in mammals, making Galf metabolic enzymesUGM activity. We postulate that inhibitors of CeUGM can serve as chemical probes of Galf in nematodes

  20. Fatal Human Meningoencephalitis due to Halicephalobus Nematodes, Germany

    PubMed Central

    Monoranu, Camelia-Maria; Müllges, Wolfgang; Keppler, Marc; Brehm, Klaus; Ondrejka, Sarah L.; Muntau, Birgit; Tannich, Egbert; Müller-Hermelink, Hans Konrad; Tappe, Dennis

    2015-01-01

    Infections with Halicephalobus nematodes, causative agents of severe meningoencephalitis in horses, have rarely been reported in humans. In this study, the clinical, serological, cytokine, and histopathological findings of a rapidly progressive and eventually fatal meningoencephalitis in a previously healthy human are described. The helminth was finally diagnosed by specific polymerase chain reactions from post mortem tissue.

  1. Ups and downs of RNA interference in parasitic nematodes

    Microsoft Academic Search

    Collette Britton; Buddhini Samarasinghe; David P. Knox

    RNA interference (RNAi) is widely used in Caenorhabiditis elegans to identify essential gene function. In parasitic nematodes RNAi has been reported to result in transcript knockdown of some target genes, but not others, thus limiting its use as a potential functional genomics tool. We recently extended work in Haemonchus contortus to examine why only some genes seem to be susceptible

  2. An automated system for measuring parameters of nematode sinusoidal movement

    Microsoft Academic Search

    Christopher J Cronin; Jane E Mendel; Saleem Mukhtar; Young-Mee Kim; Robert C Stirbl; Jehoshua Bruck; Paul W Sternberg

    2005-01-01

    BACKGROUND: Nematode sinusoidal movement has been used as a phenotype in many studies of C. elegans development, behavior and physiology. A thorough understanding of the ways in which genes control these aspects of biology depends, in part, on the accuracy of phenotypic analysis. While worms that move poorly are relatively easy to describe, description of hyperactive movement and movement modulation

  3. FUNCTIONAL GENOMIC ANALYSIS OF WALNUT-NEMATODE INTERACTIONS

    Microsoft Academic Search

    Monica T. Britton; Charles A. Leslie; Gale H. McGranahan; Abhaya M. Dandekar

    Plant parasitic nematodes can devastate walnut orchards and are able to remain dormant deep in the soil profile for several years, beyond where traditional pesticides can penetrate. The only effective pesticides are often very toxic to beneficial organisms and are detrimental to the environment; several of the most effective are in the process of being phased-out. To develop novel methods

  4. Cell Lineages of the Embryo of the Nematode Caenorhabditis elegans

    Microsoft Academic Search

    Uwe Deppe; Einhard Schierenberg; Thomas Cole; Christian Krieg; David Schmitt; Bonita Yoder; Gunter von Ehrenstein

    1978-01-01

    Embryogenesis of the free-living soil nematode Caenorhabditis elegans produces a juvenile having about 550 cells at hatching. We have determined the lineages of 182 cells by tracing the divisions of individual cells in living embryos. An invariant pattern of cleavage divisions of the egg generates a set of stem cells. These stem cells are the founders of six stem cell

  5. Biomechanical analysis of gait adaptation in the nematode Caenorhabditis elegans

    E-print Network

    Biomechanical analysis of gait adaptation in the nematode Caenorhabditis elegans Christopher Fang to adapt its locomotory gait to its physical surroundings. The nema- tode Caenorhabditis elegans, between swimming in water and crawling on surfaces, adapts its locomotory gait to surroundings that impose

  6. Induction of Tolerance to Root-Knot Nematode by Oxycom

    PubMed Central

    Anwar, Safdar A.; McKenry, M. V.; Yang, Kwang-Yeol; Anderson, A. J.

    2003-01-01

    Oxycom applications increased plant growth and population levels of Meloidogyne incognita on susceptible tomato. A single Oxycom drench at 2,500 ppm applied 7 days prior to inoculation with M. incognita provided remediation of plant growth measured 63 days later. This occurred without reducing nematode population levels. Follow-up drenches at 2,500 ppm at 10-day intervals stunted shoots and roots (P = 0.05). The same application rates at 20-day intervals did not reduce plant growth. Plants receiving multiple drenches had more galls (P = 0.05), females, and second-stage juveniles (J2) per root system compared to plants receiving only the single treatment. Foliar mass and height of plants treated with a single pre-inoculation Oxycom drench were indistinguishable from plants without nematodes. Oxycom treatments activated signaling pathways for plant defense as confirmed by detection of elevated defense gene transcripts in root tissues. The finding of increased reproduction of root-knot nematode without loss of plant growth is consistent with the definition of induced tolerance. Frequency, rate, and timing of applications need further study with other nematodes and various field settings. PMID:19262766

  7. ASSESSMENT OF SEED TREATMENTS FOR MANAGEMENT OF NEMATODES IN GEORGIA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nematodes are an important problem for cotton growers in Georgia. In addition to crop rotation, growers use nematicides to minimize yield loss. Seed treatments including Avicta, N-Hibit, and an abamectin treatment were assessed for efficacy and compared to standard nematicides in trials conducted ...

  8. Evaluation of coffee genotypes for root-knot nematode resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Meloidogyne konaensis causes severe damage to the root systems of Coffea arabica cv. Typica ‘Guatemala’ grown in Kona, Hawaii. Farmers currently employ grafting of the nematode tolerant C. liberica var. dewevrei ‘Fukunaga’ to C. arabica cv. Typica scions. Greenhouse experiments confirmed C. liberi...

  9. WEEDS AS HOSTS FOR THE SOUTHERN ROOT-KNOT NEMATODE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The southern root-knot nematode, Meloidogyne incognita, can reproduce on many different plants, including many weeds, but the amount of reproduction that occurs on weeds is not well documented. This study was conducted to document the relative host status of weeds common in Georgia. Seeds of cotton,...

  10. ENTOMOPATHOGENIC NEMATODES FOR CONTROL OF OVERWINTERING NAVEL ORANGEWORM

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study evaluated the effect of both application rate and soil temperature on the success of the entomopathogenic nematode (EPN) Steinernema carpocapsae, for use against navel orangeworm (NOW) larvae in pistachios on the berm. In most trials, the berm was moistened for two hours using microsprin...

  11. Dietary copper sulfate for control of gastrointestinal nematodes in goats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prevalence of anthelmintic resistance in goats has necessitated studies for alternative means of gastrointestinal nematode (GIN) control. The objective was to determine the effectiveness of dietary copper sulfate for control of GIN in meat goats. Naturally infected buck kids received 0 (LC), 78 (M...

  12. Garlic exhibits lack of control over gastrointestinal nematodes in goats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gastrointestinal nematodes (GIN) continue to hinder small ruminant production because of anthelmintic resistance and lack of effective products for GIN control in organic production. The objective of this study was to examine the effectiveness of a commercially available certified organic garlic pr...

  13. Genetic and Pharmacological Factors That Influence Reproductive Aging in Nematodes

    E-print Network

    Kornfeld, S. Kerry

    of America Age-related degenerative changes in the reproductive system are an important aspect of agingGenetic and Pharmacological Factors That Influence Reproductive Aging in Nematodes Stacie E. Hughes, because reproductive success is the major determinant of evolutionary fitness. Caenorhabditis elegans

  14. The Wolbachia endosymbiont as an anti-filarial nematode target

    PubMed Central

    Taylor, Mark J.; Foster, Jeremy M.

    2010-01-01

    Human disease caused by parasitic filarial nematodes is a major cause of global morbidity. The parasites are transmitted by arthropod intermediate hosts and are responsible for lymphatic filariasis (elephantiasis) or onchocerciasis (river blindness). Within these filarial parasites are intracellular alpha-proteobacteria, Wolbachia, that were first observed almost 30 years ago. The obligate endosymbiont has been recognized as a target for anti-filarial nematode chemotherapy as evidenced by the loss of worm fertility and viability upon antibiotic treatment in an extensive series of human trials. While current treatments with doxycycline and rifampicin are not practical for widespread use due to the length of required treatments and contraindications, anti-Wolbachia targeting nevertheless appears a promising alternative for filariasis control in situations where current programmatic strategies fail or are unable to be delivered and it provides a superior efficacy for individual therapy. The mechanisms that underlie the symbiotic relationship between Wolbachia and its nematode hosts remain elusive. Comparative genomics, bioinfomatic and experimental analyses have identified a number of potential interactions, which may be drug targets. One candidate is de novo heme biosynthesis, due to its absence in the genome sequence of the host nematode, Brugia malayi, but presence in Wolbachia and its potential roles in worm biology. We describe this and several additional candidate targets, as well as our approaches for understanding the nature of the host-symbiont relationship. PMID:20730111

  15. The Feeding Tube of Cyst Nematodes: Characterisation of Protein Exclusion

    PubMed Central

    Eves-van den Akker, Sebastian; Lilley, Catherine J.; Ault, James R.; Ashcroft, Alison E.; Jones, John T.; Urwin, Peter E.

    2014-01-01

    Plant parasitic nematodes comprise several groups; the most economically damaging of these are the sedentary endoparasites. Sedentary endoparasitic nematodes are obligate biotrophs and modify host root tissue, using a suite of effector proteins, to create a feeding site that is their sole source of nutrition. They feed by withdrawing host cell assimilate from the feeding site though a structure known as the feeding tube. The function, composition and molecular characteristics of feeding tubes are poorly characterised. It is hypothesised that the feeding tube facilitates uptake of host cell assimilate by acting as a molecular sieve. Several studies, using molecular mass as the sole indicator of protein size, have given contradictory results about the exclusion limits of the cyst nematode feeding tube. In this study we propose a method to predict protein size, based on protein database coordinates in silico. We tested the validity of these predictions using travelling wave ion mobility spectrometry – mass spectrometry, where predictions and measured values were within approximately 6%. We used the predictions, coupled with mass spectrometry, analytical ultracentrifugation and protein electrophoresis, to resolve previous conflicts and define the exclusion characteristics of the cyst nematode feeding tube. Heterogeneity was tested in the liquid, solid and gas phase to provide a comprehensive evaluation of three proteins of particular interest to feeding tube size exclusion, GFP, mRFP and Dual PI. The data and procedures described here could be applied to the design of plant expressed defence compounds intended for uptake into cyst nematodes. We also highlight the need to assess protein heterogeneity when creating novel fusion proteins. PMID:24489891

  16. Reflections on Plant and Soil Nematode Ecology: Past, Present and Future

    PubMed Central

    Ferris, Howard; Griffiths, Bryan S.; Porazinska, Dorota L.; Powers, Thomas O.; Wang, Koon-Hui; Tenuta, Mario

    2012-01-01

    The purpose of this review is to highlight key developments in nematode ecology from its beginnings to where it stands today as a discipline within nematology. Emerging areas of research appear to be driven by crop production constraints, environmental health concerns, and advances in technology. In contrast to past ecological studies which mainly focused on management of plant-parasitic nematodes, current studies reflect differential sensitivity of nematode faunae. These differences, identified in both aquatic and terrestrial environments include response to stressors, environmental conditions, and management practices. Methodological advances will continue to influence the role nematodes have in addressing the nature of interactions between organisms, and of organisms with their environments. In particular, the C. elegans genetic model, nematode faunal analysis and nematode metagenetic analysis can be used by ecologists generally and not restricted to nematologists. PMID:23482864

  17. The Maturity Index, the evolution of nematode life history traits, adaptive radiation and cp-scaling

    Microsoft Academic Search

    Tom Bongers

    1999-01-01

    Nematodes are increasingly being used in environmental studies. One of the potential parameters to measure the impact of disturbances\\u000a and to monitor changes in structure and functioning of the below-ground ecosystem is the nematode Maturity Index; an index\\u000a based on the proportion of colonizers (r-strategists s.l.) and persisters (K-strategists s.l.) in samples. In this paper the\\u000a original allocation of nematode

  18. Nematode community changes associated with decomposition of Crotalaria juncea amendment in litterbags

    Microsoft Academic Search

    K.-H. Wang; R. McSorley; A. J. Marshall; R. N. Gallaher

    2004-01-01

    Effects of sunn hemp (Crotalaria juncea) residue (C:N = 18.9:1) decomposition on the dynamics of free-living nematodes involved in soil nutrient cycling were examined in plots planted with sweet corn (Zea mays). Abundance of bacterivorous and fungivorous nematodes in litterbags containing sunn hemp residues peaked at 14 days after burial (DAB) followed by increase of omnivorous nematodes at 28 DAB.

  19. The effects of nematodes on bacterial activity and abundance in a freshwater sediment

    Microsoft Academic Search

    Walter Traunspurger; Matthias Bergtold; Willem Goedkoop

    1997-01-01

    The effects of natural nematode communities on bacterial activity and abundance were investigated in a microcosm study. Nematodes\\u000a were added at different densities to a freshwater sediment and bacterial parameters were measured after 1, 5, 9, and 17 days.\\u000a Significant effects of nematode density on bacterial activity were noted on day 5. No long-term changes in bacterial activity\\u000a were recorded.

  20. Efficacy of an energy block containing Duddingtonia flagrans in the control of gastrointestinal nematodes of sheep

    Microsoft Academic Search

    María F. Sagüés; Luis A. Fusé; Alicia S. Fernández; Lucía E. Iglesias; Fabiana C. Moreno; Carlos A. Saumell

    The efficacy of the nematode-trapping fungus Duddingtonia flagrans incorporated into an energy block was evaluated for the control of gastrointestinal nematodes in sheep. Four naturally parasitised\\u000a sheep with average nematode egg counts of 2,470 eggs per gram grazed by pairs on two similar parasite-free paddocks for 30 days.\\u000a During that period, one pair of sheep (treated animals, T1) received an energy

  1. The predicted impact of possible climatic change on virus-vector nematodes in Great Britain

    Microsoft Academic Search

    R. Neilson; B. Boag

    1996-01-01

    Data extracted from surveys of plant-parasitic nematodes in Great Britain allowed relatively detailed maps of the geographical distribution of various longidorid and trichodorid virus-vector nematode species to be produced. These distributions are related to long-term monthly mean temperature. Recently published figures for climate change were applied to the distribution data. A potential increase in nematode associated problems due to climate

  2. Modes of action associated with microbially induced in planta suppression of plant-parasitic nematodes

    Microsoft Academic Search

    R. A. Sikora; K. Schäfer; A. A. Dababat

    2007-01-01

    This article discusses the extensive research that has been conducted on the use of mutualistic bacterial and fungal endophytes\\u000a for the biological control of plant-parasitic nematodes. This review deals in particular with the modes of action of multitrophic\\u000a interactions involving endophytic bacteria or fungi that have biological control activity towards the root-knot nematode,\\u000a Meloidogyne incognita, and the potato cyst nematode,

  3. Noncanonical cell death in the nematode Caenorhabditis elegans

    PubMed Central

    Kinet, Maxime J.; Shaham, Shai

    2014-01-01

    The nematode Caenorhabditis. elegans has served as a fruitful setting for cell death research for over three decades. A conserved pathway of four genes, egl-1/BH3-only, ced-9/Bcl-2, ced-4/Apaf-1, and ced-3/caspase, coordinates most developmental cell deaths in C. elegans. However, other cell death forms, programmed and pathological, have also been described in this animal. Some of these share morphological and/or molecular similarities with the canonical apoptotic pathway, while others do not. Indeed, recent studies suggest the existence of an entirely novel mode of programmed developmental cell destruction that may also be conserved beyond nematodes. Here we review evidence for these noncanonical pathways. We propose that different cell death modalities can function as backup mechanisms for apoptosis, or as tailor-made programs that allow specific dying cells to be efficiently cleared from the animal. PMID:25065890

  4. Structure and Function of Nematode RNA-Binding Proteins

    PubMed Central

    Kaymak, Ebru; Wee, L.M.; Ryder, Sean P.

    2010-01-01

    RNA-binding proteins are critical effectors of gene expression. They guide mRNA localization, translation, and stability, and potentially play a role in regulating mRNA synthesis. The structural basis for RNA recognition by RNA-binding proteins is the key to understanding how they target specific transcripts for regulation. Compared to other metazoans, nematode genomes contain a significant expansion in several RNA-binding protein families, including Pumilio-FBF (PUF), TTP-like zinc finger (TZF), and argonaute-like (AGO) proteins. Genetic data suggest that individual members of each family have distinct functions, presumably due to sequence variations that alter RNA binding specificity or protein interaction partners. In this review, we highlight example structures and identify the variable regions that likely contribute to functional divergence in nematodes. PMID:20418095

  5. On the Transport of Nematodes by the Wind

    PubMed Central

    Carroll, J. J.; Viglierchio, D. R.

    1981-01-01

    The possible effectiveness of atmospheric transport of nematode forms (dry larvae or eggs) as a means for introducing new species to a given environment is examined. Given the measured sedimentation velocities for a range of forms (0.1 ? Ws ? 0.6 mps), the necessary conditions on the wind speed required for natural erosion are defined. With these results scenarios for lofting, transport, and diffusion of these forms are examined using relevant gaussian plume models. Results indicate that on rare occasions individuals can be deposited up to 40 km from their original location. Redepositions up to 5 km per erosion event should be fairly common occurances when dry loose soil conditions or dry tillage operations combine with optimal atmospheric conditions and the presence of significant numbers of nematodes at the surface. PMID:19300792

  6. Occurrence of the Clover Cyst Nematode, Heterodera trifolii, in Prince Edward Island Soils

    PubMed Central

    Kimpinski, J.; Plumas, G.; MacDonald, M. C.

    1993-01-01

    In a survey of potato and rotational crops on Prince Edward Island, Canada, the cyst stage of the clover cyst nematode, Heterodera trifolii, was found in 43 of 63 sites sampled; however, only 12% of the cysts contained eggs. The root lesion nematode, Pratylenchus penetrans, was the dominant plant parasitic nematode and was found in 56 sites. Extraction of cysts from soil was similar using either the Schuiling centrifuge or the Fenwick can method, although the former was more convenient to use. The modified Baermann funnel method was not efficient for detecting the clover cyst nematode in soil. PMID:19279856

  7. Free-Living Nematodes in the Freshwater Food Web: A Review

    PubMed Central

    Majdi, Nabil; Traunspurger, Walter

    2015-01-01

    Free-living nematodes are well-recognized as an abundant and ubiquitous component of benthic communities in inland waters. Compelling evidence from soil and marine ecosystems has highlighted the importance of nematodes as trophic intermediaries between microbial production and higher trophic levels. However, the paucity of empirical evidence of their role in freshwater ecosystems has hampered their inclusion in our understanding of freshwater food web functioning. This literature survey provides an overview of research efforts in the field of freshwater nematode ecology and of the complex trophic interactions between free-living nematodes and microbes, other meiofauna, macro-invertebrates, and fishes. Based on an analysis of the relevant literature and an appreciation of the potential of emerging approaches for the evaluation of nematode trophic ecology, we point out research gaps and recommend relevant directions for further research. The latter include (i) interactions of nematodes with protozoans and fungi; (ii) nonconsumptive effects of nematodes on microbial activity and the effects of nematodes on associated key ecosystem processes (decomposition, primary production); and (iii) the feeding selectivity and intraspecific feeding variability of nematodes and their potential impacts on the structure of benthic communities. PMID:25861114

  8. The size structure of nematode assemblages along a Mediterranean deep-sea transect

    NASA Astrophysics Data System (ADS)

    Soetaert, Karline; Heip, Carlo

    1989-01-01

    The nematode assemblages along a deep-sea transect in the Mediterranean are composed of individuals that are as small as those found in other areas at much greater depth. This may be related to the low surface primary production since chloroplastic pigment equivalent (CPE) values in the sediments are low as well. A significant decrease of both nematode size and sedimentary CPE values with increasing water depth was found. At all water depths average nematode length increases with depth in the sediment (0-2 cm) due to the decreasing abundance of smaller nematodes.

  9. The Comparative Effects of Chloramines on a Range of Nematodes

    PubMed Central

    Viglierchio, D. R.; Croll, N. A.

    1969-01-01

    Chloramine-T (sodium p-toluene sulfonchloramide) was a good surface sterilant for Ditylenchus dipsaci, however it was somewhat nematicidal. These properties were presumably associated with its properties as an oxidizing chlorine. Other chloramines tested were also toxic. Its possible use as a nematicide is suggested in relation to dosage and phytotoxicity. The comparative effects of chloramines on a wide range of freeliving soil nematodes and freeliving infective larvae of animal parasitic forms are included. PMID:19325651

  10. Reindeer as hosts for nematode parasites of sheep and cattle

    Microsoft Academic Search

    J. T. Hrabok; A. Oksanen; M. Nieminen; A. Rydzik; A. Uggla; P. J. Waller

    2006-01-01

    The reindeer husbandry range of Scandinavia overlaps with sheep, goat, and cattle pastures. The aim of this study was to determine whether reindeer are suitable hosts for ovine or bovine nematode parasites, and thus may spread these parasites into the reindeer husbandry regions. To render worm-free, twelve 4-month-old male reindeer calves, six lambs, and six bovine calves were given ivermectin

  11. Nematode community structure in the vicinity of a metallurgical factory.

    PubMed

    Salamún, Peter; Ren?o, Marek; Miklisová, Dana; Hanzelová, Vladimíra

    2011-12-01

    Soil nematode communities (taxa composition, trophic structure, ecological indices) in the area of metallurgical factory (Oravské ferozliatinárske závody) in Široká, Northern Slovakia were investigated in 2009. The factory belongs to main sources of emissions originated by ferroalloy production in this region. Four sites (meadows) were selected in a downwind direction from the factory: site A was located 0.85 km far from the factory, and the other sites were maintained in approximately 2-km intervals from each other. Chemical analysis of soil samples showed low concentrations of heavy metals (As, Cd, Cr, Cu, Ni, Pb and Zn), with all values being under Slovak limit concentrations of heavy metals in soils. Only the Cd content in the soil sample from site A slightly exceeded the allowable threshold, but it was decreasing with the distance from the factory, similarly as remaining metals except Cr, with slightly increasing trend of concentration. Within 64 identified nematode genera, the Helicotylenchus, Paratylenchus, Pratylenchus, Acrobeloides, Cephalobus and Rhabditis were most common and eudominant. This was clearly reflected on the trophic structure of nematode communities, where plant feeding nematodes and bacteriovorous prevailed. Significant negative correlation (P?

  12. Sex and age-biased nematode prevalence in reptiles.

    PubMed

    Brown, David S; Symondson, William O C

    2014-08-01

    Prevalence and intensity of parasitic infections are often higher in male than in female vertebrates. This bias may represent either differences between host sex in exposure or susceptibility to parasites. The former may be due to sex-specific behaviour of the host, including differential habitat use or diet. Differences in susceptibility are often regarded as a negative effect of male sex steroid hormones on the immune system. Host-parasite dynamics are of great interest in terms of reptile survival, ecology and conservation. We used, for the first time, molecular diagnostics to track nematode parasitism in wild populations of reptiles noninvasively. Using slow worms (Anguis fragilis) as a model species, we investigated the interacting effects of time of year, sex, length, weight and climatic variables on the prevalence of the gastroenterological parasitic nematode Neoxysomatium brevicaudatum. Faeces were collected from three sites over 2 years. There was an interaction between sex and time of year, with lower nematode prevalence in males than in females in July or August (different between years) but a high prevalence in males in April. As the latter is during the slow worm breeding season, this may be the result of testosterone-induced immunosuppression. A second-order interaction between slow worm length and weight was found to be significant, with a positive association between prevalence and body condition in young slow worms and a negative association in older slow worms. The convex pattern of nematode prevalence with age that emerged suggests an increase with age-related exposure and a decrease with age-related acquired immunity. PMID:24612272

  13. Host-finding behaviour in the nematode Pristionchus pacificus

    PubMed Central

    Brown, Federico D.; D'Anna, Isabella; Sommer, Ralf J.

    2011-01-01

    Costs and benefits of foraging have been studied in predatory animals. In nematodes, ambushing or cruising behaviours represent adaptations that optimize foraging strategies for survival and host finding. A behaviour associated with host finding of ambushing nematode dauer juveniles is a sit-and-wait behaviour, otherwise known as nictation. Here, we test the function of nictation by relating occurrence of nictation in Pristionchus pacificus dauer juveniles to the ability to attach to laboratory host Galleria mellonella. We used populations of recently isolated and mutagenized laboratory strains. We found that nictation can be disrupted using a classical forward genetic approach and characterized two novel nictation-defective mutant strains. We identified two recently isolated strains from la Réunion island, one with a higher proportion of nictating individuals than the laboratory strain P. pacificus PS312. We found a positive correlation between nictation frequencies and host attachment in these strains. Taken together, our combination of genetic analyses with natural variation studies presents a new approach to the investigation of behavioural and ecological functionality. We show that nictation behaviour in P. pacificus nematodes serves as a host-finding behaviour. Our results suggest that nictation plays a role in the evolution of new life-history strategies, such as the evolution of parasitism. PMID:21411455

  14. Differential vascularization of nematode-induced feeding sites.

    PubMed

    Hoth, Stefan; Stadler, Ruth; Sauer, Norbert; Hammes, Ulrich Z

    2008-08-26

    Sedentary nematodes are destructive plant pathogens that cause significant yield losses. In the roots of their host plants, cyst nematodes (CNs) and root-knot nematodes (RKNs) induce different, highly specialized feeding sites--syncytia or giant cells (GCs), respectively--to optimize nutrient uptake. We compared the mechanisms by which nutrients are delivered from the model host plant, Arabidopsis, to GCs induced by the RKN Meloidogyne incognita or to syncytia induced by the CN Heterodera schachtii. From previous work, syncytia were known to be symplastically connected to newly formed host phloem composed of sieve elements (SEs) and companion cells. Here we studied the formation of plasmodesmata (PD) during GC and syncytia development by monitoring a viral movement protein that targets branched PD and the development of host phloem during GC formation by applying confocal laser scanning microscopy and immunocytochemistry. Analyses of plants expressing soluble or membrane-anchored green fluorescent protein in their phloem demonstrated symplastic isolation of GCs. GCs were found to be embedded in a tissue that consists exclusively of SEs. These de novo-formed SEs, contained nuclei and were interconnected by secondary PD. A similar interconnection of SEs was observed around syncytia. However, these secondary PD were also present at the SE-syncytium interface, demonstrating the postulated symplastic connection. Our results show that CNs and RKNs, despite their close phylogenetic relatedness, employ fundamentally different strategies to withdraw nutrients from host plants. PMID:18711135

  15. Epidermal Wound Healing in the Nematode Caenorhabditis elegans

    PubMed Central

    Chisholm, Andrew D.

    2015-01-01

    Significance: Healing of epidermal wounds is a fundamentally conserved process found in essentially all multicellular organisms. Studies of anatomically simple and genetically tractable model invertebrates can illuminate the roles of key genes and mechanisms in wound healing. Recent Advances: The nematode skin is composed of a simple epithelium, the epidermis (also known as hypodermis), and an associated extracellular cuticle. Nematodes likely have a robust capacity for epidermal repair; yet until recently, relatively few studies have directly analyzed wound healing. Here we review epidermal wound responses and repair in the model nematode Caenorhabditis elegans. Critical Issues: Wounding the epidermis triggers a cutaneous innate immune response and wound closure. The innate immune response involves upregulation of a suite of antimicrobial peptides. Wound closure involves a Ca2+-triggered rearrangement of the actin cytoskeleton. These processes appear to be initiated independently, yet, their coordinated activity allows the animal to survive otherwise fatal skin wounds. Future Directions: Unanswered questions include the nature of the damage-associated molecular patterns sensed by the epidermis, the signaling pathways relaying Ca2+ to the cytoskeleton, and the mechanisms of permeability barrier repair. PMID:25945288

  16. Nematode community structure along a central Chile margin transect influenced by the oxygen minimum zone

    NASA Astrophysics Data System (ADS)

    Neira, Carlos; King, Ian; Mendoza, Guillermo; Sellanes, Javier; De Ley, Paul; Levin, Lisa A.

    2013-08-01

    Nematodes are among the metazoans most tolerant of low-oxygen conditions and play major roles in seafloor ecosystem processes. Nematode communities were studied in sediments off Concepción, Central Chile, spanning the outer shelf within the OMZ (122 m) to the mid-lower continental slope (972 m) beneath the OMZ. The total density and biomass of nematodes (core depth 0-10 cm) ranged from 677 to 2006 ind. 10 cm-2, and 168.4 to 506.5 ?g DW 10 cm-2, respectively. Among metazoan meiofaunal taxa, nematodes predominated at all sites both in terms of relative abundance (83.7-99.4%) and biomass (53.8-88.1%), followed by copepods, nauplii and polychaetes. Nematodes were represented by 33 genera distributed among 17 families, with densities greatest at low oxygen sites (122-364 m; ~2000 ind. 10 cm-2). Nematode generic and trophic diversity, and individual biomass were lowest, and Rank 1 dominance was highest, at the most oxygen-depleted site (122 m), despite the fact that the organic carbon content of the sediment was maximal at this depth. At the most oxygenated slope sites (827 and 972 m), all of Wieser's nematode feeding groups were represented. In contrast, at the lowest-oxygen site, only selective deposit (bacterial) feeders (1A) were present, indicating a reduction in trophic complexity. A large percentage of nematodes inhabited subsurface sediment layers (>1 cm). At deeper, more oxygenated sites (827 and 972 m), nematode individual biomass increased downcore, while within the OMZ, nematode biomass was low and remained relatively uniform through the sediment column. The concentration of nematodes in deeper sediment layers, the vertical distribution of the feeding groups, as well as the high nutritional quality of the deeper layers, suggest a differential resource partitioning of the food available, which may reduce interspecific competition.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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, nematode secreted effe...

  18. Development of an In Vivo RNAi Protocol to Investigate Gene Function in the Filarial Nematode, Brugia malayi

    Microsoft Academic Search

    Chuanzhe Song; Jack M. Gallup; Tim A. Day; Lyric C. Bartholomay; Michael J. Kimber

    2010-01-01

    Our ability to control diseases caused by parasitic nematodes is constrained by a limited portfolio of effective drugs and a paucity of robust tools to investigate parasitic nematode biology. RNA interference (RNAi) is a reverse-genetics tool with great potential to identify novel drug targets and interrogate parasite gene function, but present RNAi protocols for parasitic nematodes, which remove the parasite

  19. Ecological Biogeography of the Terrestrial Nematodes of Victoria Land, Antarctica 29 Ecological Biogeography of theTerrestrial

    E-print Network

    Wall, Diana

    Ecological Biogeography of the Terrestrial Nematodes of Victoria Land, Antarctica 29 Ecological Biogeography of theTerrestrial Nematodes ofVictoria Land,Antarctica Byron J. Adams1 , Diana H. Wall2 , Ross A of the Terrestrial Nematodes of Victoria Land, Antarctica. ZooKeys 419: 29­71. doi: 10.3897/zookeys.419.7180 Abstract

  20. Resistance in peanut cultivars and breeding lines to three root-knot nematode species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Three major species of root-knot nematode infect peanut: Meloidogyne arenaria race 1 (Ma), M. hapla (Mh), and M. javanica race 3 (Mj). Sources of resistance to all three nematodes are needed for developing novel peanut cultivars with broad resistance to Meloidogyne spp. Cultivars and breeding lines ...

  1. Endosymbiont DNA in Endobacteria-Free Filarial Nematodes Indicates Ancient Horizontal Genetic Transfer

    Microsoft Academic Search

    Samantha N. McNulty; Jeremy M. Foster; Makedonka Mitreva; Julie C. Dunning Hotopp; John Martin; Kerstin Fischer; Bo Wu; Paul J. Davis; Sanjay Kumar; Norbert W. Brattig; Barton E. Slatko; Gary J. Weil; Peter U. Fischer; Laurent Rénia

    2010-01-01

    BackgroundWolbachia are among the most abundant symbiotic microbes on earth; they are present in about 66% of all insect species, some spiders, mites and crustaceans, and most filarial nematode species. Infected filarial nematodes, including many pathogens of medical and veterinary importance, depend on Wolbachia for proper development and survival. The mechanisms behind this interdependence are not understood. Interestingly, a minority

  2. USDA ARS RESEARCH PROGRAMS ON MICROBES FOR MANAGEMENT OF PLANT-PARASITIC NEMATODES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Restrictions on use of conventional nematicides have increased the need for new methods of managing plant-parasitic nematodes. Consequently, nematode-antagonistic microbes, and active compounds produced by such organisms, are being explored as potential additions to management practices. Programs ...

  3. Public Soybean Breeding Lines Tested for Reniform Nematode (Rotylenchulus reniformis) Reproduction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the Southeastern United States reniform nematode (Rotylenchulus reniformis) causes considerable damage and yield loss to soybean and cotton. No cotton varieties have reniform nematode resistance, whereas several sources of resistance exist in soybean. This resistance is often linked to resistance...

  4. Molecular and functional characterization of parasitism genes of the potato cyst nematode Globodera rostochiensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potato cyst nematodes (Globodera rostochiensis and G. pallida) are quarantined pests threatening the potato industry in the United States. Secreted proteins encoded by parasitism genes expressed in the esophageal gland cells of plant-parasitic nematodes represent the primary molecules involved in p...

  5. Molecular and functional characterization of parasitism genes of the potato cyst nematode Globodera rostochiensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Potato cyst nematodes (Globodera rostochiensis and G. pallida) are quarantined pests threatening the potato industry in the United States. Secreted proteins encoded by parasitism genes expressed in the esophageal gland cells of plant-parasitic nematodes represent the primary molecules involved in pl...

  6. FIRST REPORT OF THE PALE CYST NEMATODE (GLOBODERA PALLIDA) IN THE UNITED STATES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2006, a cyst nematode was discovered in tare dirt at a potato processing facility in eastern Idaho. The nematode was found during a routine survey conducted jointly by the Idaho State Department of Agriculture and the USDA Animal and Plant Health Inspection Service through the Cooperative Agricul...

  7. Extensive mitochondrial gene rearrangement in a genus of plant parasitic nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The nematodes Globodera pallida and G. rostochiensis are two of the only animals known to have multipartite mitochondrial genomes. In such genomes, mitochondrial genes are distributed on multiple circles. The entire sequence of a nematode (Radopholus similis) that belongs to the same superfamily (...

  8. Cloning, expression and functional characterisation of a peroxiredoxin from the potato cyst nematode Globodera rostochiensis

    Microsoft Academic Search

    Lee Robertson; Walter M Robertson; Miroslaw Sobczak; Johannes Helder; Emmanuel Tetaud; Mark R Ariyanayagam; Mike A. J Ferguson; Alan Fairlamb; John T Jones

    2000-01-01

    We report the cloning, expression and functional characterisation of a peroxidase belonging to the peroxiredoxin family from the potato cyst nematode Globodera rostochiensis, the first molecule of this type from any nematode parasitic on plants. The G. rostochiensis peroxiredoxin catalyses the breakdown of hydrogen peroxide, but not cumene or t-butyl hydroperoxide, in a trypanosomatid reducing system comprising trypanothione reductase, trypanothione

  9. PARASITISM GENES IDENTIFIED IN THE POTATO CYST NEMATODE, GLOBODERA ROSTOCHIENSIS, USING A COMPARATIVE GENOMIC APPROACH

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stylet secretions are encoded by parasitism genes expressed in the esophageal gland cells of plant-parasitic nematodes. These are the primary signals that facilitate nematode migration in host roots and control the formation of the elaborate feeding cells necessary for the development and reproduct...

  10. Transcript Analysis of Parasitic Females of the Sedentary Semi-Endoparasitic Nematode Rotylenchulus reniformis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The reniform nematode, Rotylenchulus reniformis Linford & Oliveira, is a sedentary semi-endoparasitic roundworm that infects the roots of many economically important plant species. Engineered resistance to plant-parasitic nematodes (PPNs) via RNA-interference (RNAi) has shown promise in providing h...

  11. Biological Control of the Nematode Infective larvae of Trichostrongylidae Family With Filamentous Fungi

    PubMed Central

    Zarrin, Majid; Rahdar, Mahmoud; Gholamian, Abbas

    2015-01-01

    Background: Biological control of parasitic nematodes by microorganisms is a promising approach to control such parasites. Microorganisms such as fungi, viruses and bacteria are recognized as biocontrol agents of nematodes. Objectives: The current study mainly aimed to evaluate the in vitro Potential of various saprophyte soil-fungi in reducing the infective larvae stage of parasitic nematode Trichostrongylidae family. Materials and Methods: Sheep feces were employed to provide the required third stage larvae source for the experiments. The nematode infective larvae of Trichostrongylidae family including three species of Ostertagia circumcincta, Marshalgia marshali and Heamonchos contortus were collected by Berman apparatus. Fifteen isolates of filamentous fungi were tested in the current study. One milliliter suspension containing 200 third stage larvae of Trichostrongylidae family was separately added to the fungal cultures in 2% water-agar medium Petri-dishes. Every day the live larvae were counted with light microscope (10X) and the number of captured larvae was recorded on different days. Results: Significant differences were observed in the results of co-culture of nematodes larva and fungi after seven days. The most effective fungi against the nematodes larvae were Cladosporium sp., Trichoderma sp., Fusarium equisetti, after seven days of incubation. Conclusions: The studies on fungi could be applied as suitable tools in biocontrol of nematode infections. However, additional surveys are required to select efficient with the ability to reduce the nematode larvae in the environment. PMID:25893084

  12. Identification of a SNP marker associated with WB242 nematode resistance in sugar beet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The beet-cyst nematode (Heterodera schachtii Schmidt) is one of the major diseases of sugar beet. The identification of molecular markers associated to the nematode resistance would be helpful for developing resistant varieties. The aim of this study was the identification of SNP (Single Nucleotide ...

  13. Development of a desiccated cadaver delivery system to apply entomopathogenic nematodes for control of soil pests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pentomopathogenic nematodes may be more capable of controlling soil pests when they are harbored by desiccated cadavers. A small-scale system was developed from a modified crop seed planter to effectively deliver desiccated nematode-infected cadavers into the soil. The system mainly consists of a me...

  14. Role of nematode peptides and other small molecules in plant parasitism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Molecular, genetic, and biochemical studies are demonstrating an increasingly important role of peptide signaling in nematode parasitism of plants. To date, the majority of nematode-secreted peptides identified share similarity with plant CLAVATA3/ESR (CLE) peptides, but bioinformatics analyses of n...

  15. Screening Locally Adapted Spring Wheat Lines for Resistance to Cereal Cyst Nematode

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cereal cyst nematode (Heterodera avenae) has become an increasing problem in the high precipitation areas of eastern Washington and the Palouse. Since 2010, surveys have discovered serious infestations of this nematode, which infects wheat, barley and grassy weeds. It causes severe yield loss, restr...

  16. DIBOA: Fate in Soil and Effects on Root-knot Nematode Egg Numbers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The benzoxazinoid 2,4-dihydroxy-1,4-benzoxazin-3-one (DIBOA) is produced by rye (Secale cereale) and may contribute to plant-parasitic nematode suppression when rye plants are incorporated as a green manure. We investigated the fate of DIBOA in soil and DIBOA’s effects on nematode reproduction. Soil...

  17. Outer Ear Canal Infection with Rhabditis sp. Nematodes in a Human

    PubMed Central

    Würfel, Waldemar; Sedlacek, Ludwig; Suerbaum, Sebastian; Tappe, Dennis; Hornef, Mathias Walter

    2014-01-01

    Here we report the first human case of an outer ear canal infection with a free-living nematode of the genus Rhabditis. Otomicroscopy revealed viable worms in the outer ear canal of a patient suffering from chronic otorrhea and hearing loss. The nematode was identified by microscopy and internal transcribed spacer (ITS)-PCR. PMID:24599974

  18. INFECTIVITY OF ENTOMOPATHOGENIC NEMATODES (STEINERNEMATIDAE AND HETERORHABDITIDAE) AGAINST THE SMALL HIVE BEETLE AETHINA TUMIDA (COLEOPTERA: NITIDULIDAE)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies were conducted to compare the susceptibility of the small hive beetle wandering larvae to Steinernema riobrave, S. carpocapsae, and Heterorhabditis megidis in sand-substrate petri dishes at 25'C. Our results showed the beetles were susceptible to entomopathogenic nematodes. Lethal nematode...

  19. Effects of the mermithid nematode Ovomermis sinensis on the hemocytes of its host Helicoverpa armigera

    Microsoft Academic Search

    Qiang Li; Yalan Sun; Guoxiu Wang; Xusheng Liu

    2009-01-01

    Little is known about the mechanism by which mermithid nematodes avoid encapsulation responses of insect hosts. In this study, we investigated the influence of the mermithid nematode Ovomermis sinensis on host Helicoverpa armigera hemocyte number, encapsulation activity, spreading behavior and cytoskeleton. Parasitism by O. sinensis caused a significant increase in the total hemocyte counts (THC) and plasmatocyte numbers of H.

  20. New Discoveries in Resistances to Columbia Root-knot Nematode and Corky Ringspot Disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Columbia root-knot nematode CRKN (Meloidogyne chitwoodi) is a serious pest of potato in the Pacific Northwest. In the warmer zones, with longer growing seasons, this nematode builds up to high populations and damages the potato tubers by invading and causing discoloration and galling. It is pr...

  1. A novel approach to biocontrol: release of live insect hosts pre-infected with entomopathogenic nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As a new application approach, we tested the efficacy of releasing live insect hosts that were pre-infected with entomopathogenic nematodes against insect pests living in cryptic habitats. We hypothesized that the pre-infected hosts could carry the next generation of emerging nematode infective juv...

  2. Optimization of a host diet for in vivo production of entomopathogenic nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In previous studies, we developed an improved diet for Tenebrio molitor, a host that is used for in vivo nematode production, and we demonstrated that single insect diet components (e.g., lipids and proteins) can have a positive or negative impact on entomopathogenic nematode fitness and quality. I...

  3. THE ORDINATION OF AQUATIC NEMATODE COMMUNITIES AS AFFECTED BY STREAM WATER QUALITY

    EPA Science Inventory

    Benthic nematodes were sampled at 16 sites on two streams to investigate the relationships of nematode community structure to various water quality factors. A prominence value for each species was calculated for use in three-dimensional community ordination. Species composition o...

  4. SWIM BLADDER NEMATODES (ANGUILLICOLOIDES CRASSUS) DISTURB SILVERING IN EUROPEAN EELS (ANGUILLA ANGUILLA)

    E-print Network

    Paris-Sud XI, Université de

    SWIM BLADDER NEMATODES (ANGUILLICOLOIDES CRASSUS) DISTURB SILVERING IN EUROPEAN EELS (ANGUILLA of freshwater eel (Anguilla spp.) populations. These nematodes are known to negatively affect many fitness-related traits in eels. We used experimental infections to study the effect of A. crassus on the relative size

  5. Current status of phytoparasitic nematodes and their host plants in Egypt

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In Egypt many phytoparasitic nematodes constitute a major constraint to agricultural production, especially in sandy soil and reclaimed desert lands. Nematological surveys were conducted to determine the genera and species of phytoparasitic nematodes on associated host plants in Egypt. The results i...

  6. Response of Watermelon Germplasm to Southern Root-Knot Nematode in Field Tests

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Southern root-knot nematode (Meloidogyne incognita) is a serious pest of cultivated watermelon (Citrullus lanatus var. lanatus) in southern regions of the US. While there is no known resistance to southern root-knot nematode in watermelon cultivars to date, wild watermelon relatives (C. lanatus var...

  7. The maturity index: an ecological measure of environmental disturbance based on nematode species composition

    Microsoft Academic Search

    Tom Bongers

    1990-01-01

    Nematode assemblages constitute a potential instrument for assessing the quality of submersed, temporarily submersed, and terrestrial soils and for the development of an ecological typology and biomonitoring system. Interpretation of physical or pollution-induced disturbances has hitherto mainly been based on changes in diversity, dominance patterns or percentage of dorylaimids (Adenophorea). The maturity index, based on the nematode fauna, is proposed

  8. Observations on the foliar nematode, Aphelenchoides besseyi, infecting tuberose and rice in India

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The foliar nematode Aphelenchoides besseyi causes white tip disease in rice (Oryza sativa L.) and floral malady in tuberose (Polianthes tuberosa L.). This nematode is widely distributed in the rice fields of many states of India, including West Bengal (WB), Andhra Pradesh (AP), Madhya Pradesh (MP) a...

  9. The use of entomopathogenic nematodes in the US and issues related to genetic degradation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research and commercial application of entomopathogenic nematodes in North America has a long history. In the pursuit of commercial viability, there have been a number of success stories, but also quite a number of dead ends. We provide insight into new opportunities for entomopathogenic nematodes...

  10. Protease inhibitor expression in soybean roots exhibiting susceptible and resistance reactions to soybean cyst nematode

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Protease inhibitors play a role in regulating proteases during cellular development and in plant defense against insects and nematodes. We identified, cloned and sequenced cDNAs encoding six protease inhibitors expressed in soybean roots infected with soybean cyst nematode. Four of these protease in...

  11. Influence of host nutrition on the development and consequences of nematode parasitism in ruminants

    Microsoft Academic Search

    Robert L Coop; Ilias Kyriazakis

    2001-01-01

    Control of gastrointestinal nematodes of ruminants is based largely on use of anthelmintics combined, where practical, with pasture management. The increasing prevalence of resistance to anthelmintics has led to the search for alternative sustainable control strategies. Here, we consider how nutrition, as a short-term alternative, can influence the host–parasite relationship in ruminants, using gastrointestinal nematode infections of sheep as the

  12. Plant-parasitic nematodes associated with grapevines, Vitis vinifera, in Washington and Idaho

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surveys were conducted in eastern Washington and Idaho to determine the plant-parasitic nematodes associated with wine grape (Vitis vinifera) vineyards. The most commonly encountered plant-parasitic nematodes in eastern Washington and Idaho wine grape vineyards were Meloidogyne hapla, Paratylenchus ...

  13. Preferred use of bacteria over phytoplankton by deep-sea nematodes in polar regions

    Microsoft Academic Search

    J. Ingels; Driessche Van den P; Mesel de I. G; S. Vanhove; T. Moens; A. Vanreusel

    2010-01-01

    The present study explored the selective feeding properties of Antarctic and Arctic deep-sea nematodes within an experimental setup. Nematodes are assumed to play an important role in the carbon flux within the polar bathyal food webs, but knowledge about their natural diets is limited. For the first time, deep-sea multicore sediment samples from both polar regions were incubated aboard research

  14. Effect of nitrogen and phosphate fertilisers on microbial and nematode diversity in pasture soils

    Microsoft Academic Search

    S. U Sarathchandra; A Ghani; G. W Yeates; G Burch; N. R Cox

    2001-01-01

    Soil microbial and nematode populations, soil microbial community structure, and microbial and nematode functional diversity were studied in two fertiliser trials on perennial pasture at three sampling times. The N trial involved the application of 0, 200 and 400kg N ha?1 y?1 in the form of urea. The P trial involved the application of 0, 30, 50 and 100kg P

  15. Analysis of chitin synthase function in a plant parasitic nematode, Meloidogyne artiellia, using RNAi

    Microsoft Academic Search

    Elena Fanelli; Mauro Di Vito; John T. Jones; Carla De Giorgi

    2005-01-01

    A single chitin synthase gene is responsible for chitin production in the eggshells of the plant parasitic nematode Meloidogyne artiellia. In this paper we describe a functional analysis of this gene using RNAi as well as further analysis of two similar genes from the free-living nematode Caenorhabditis elegans. The parasitic life-style of M. artiellia required the development of a novel

  16. Tobacco rattle virus mediates gene silencing in a plant parasitic root-knot nematode

    Microsoft Academic Search

    G. Dubreuil; M. Magliano; M. P. Dubrana; J. Lozano; P. Lecomte; B. Favery; P. Abad; M. N. Rosso

    2009-01-01

    Root-knot nematodes (RKNs) are sedentary biotrophic parasites that induce the differentiation of root cells into feeding cells that provide the nematodes with the nutrients necessary for their development. The development of new control methods against RKNs relies greatly on the functional analysis of genes that are crucial for the development of the pathogen or the success of parasitism. In the

  17. Two hypotheses to explain why RNA interference does not work in animal parasitic nematodes

    Microsoft Academic Search

    M. E. Viney; F. J. Thompson

    2008-01-01

    RNA interference (RNAi) has been used extensively in model organisms such as Caenorhabditis elegans. Methods developed for RNAi in C. elegans have also been used in parasitic nematodes. However, RNAi in parasitic nematodes has been unsuccessful or has had limited success. Studies of genes essential for RNAi in C. elegans and of RNAi in Caenorhabditis spp. other than C. elegans

  18. Sequence and genetic map of Meloidogyne hapla: A compact nematode genome for plant parasitism

    Microsoft Academic Search

    Charles H. Opperman; David M. Bird; Valerie M. Williamson; Dan S. Rokhsar; Mark Burke; Jonathan Cohn; John Cromer; Steve Diener; Jim Gajan; Steve Graham; T. D. Houfek; Qingli Liu; Therese Mitros; Jennifer Schaff; Reenah Schaffer; Elizabeth Scholl; Bryon R. Sosinski; Varghese P. Thomas; Eric Windham

    2008-01-01

    We have established Meloidogyne hapla as a tractable model plant-parasitic nematode amenable to forward and reverse genetics, and we present a complete genome sequence. At 54 Mbp, M. hapla represents not only the smallest nematode genome yet completed, but also the smallest metazoan, and defines a platform to elucidate mechanisms of parasitism by what is the largest uncontrolled group of

  19. Postembryonic RNAi in Heterorhabditis bacteriophora: a nematode insect parasite and host for insect pathogenic symbionts

    Microsoft Academic Search

    Todd A Ciche; Paul W Sternberg

    2007-01-01

    BACKGROUND: Heterorhabditis bacteriophora is applied throughout the world for the biological control of insects and is an animal model to study interspecies interactions, e.g. mutualism, parasitism and vector-borne disease. H. bacteriophora nematodes are mutually associated with the insect pathogen, Photorhabdus luminescens. The developmentally arrested infective juvenile (IJ) stage nematode (vector) specifically transmits Photorhabdus luminescens bacteria (pathogen) in its gut mucosa

  20. The pine-wood nematode, Bursaphelenchus xylophilus, in Minnesota and Wisconsin: insect associates and transmission studies'

    E-print Network

    1068 The pine-wood nematode, Bursaphelenchus xylophilus, in Minnesota and Wisconsin: insect and Wisconsin: insect associates and transmission studies. Can. J. For. Res. 13: 1068-1076. The pine emerging from nematode-infested pines in Minnesota and Wisconsin during 1981 and 1982. The greatest number

  1. Registration of JTN-5203 soybean germplasm with resistance to multiple cyst nematode populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    JTN-5203 soybean [Glycine max (L.) Merr.] (Reg. No. XX-XXX, PI 664903) was developed and released by USDA-ARS in collaboration with the University of Tennessee in 2012 for its broad resistance to soybean cyst nematode (SCN; Heterodera glycines Ichinohe), as well as reniform nematode (Rotylenchulus ...

  2. Multiple species-specific controls of root-feeding nematodes in natural soils

    Microsoft Academic Search

    A. M. Piskiewicz; H. Duyts; Putten van der W. H

    2008-01-01

    One of the major limitations to enhance sustainability of crop production systems is the inability to control root-feeding nematodes without using chemical biocides. In soils under wild vegetation, however, root-feeding nematodes affect plant performance and plant community composition varying from substantially to insignificantly. Previous studies in natural ecosystems have already shown that mutualistic symbionts, such as arbuscular mycorrhizal fungi and

  3. South Carolina Pest Management Handbook for Field Crops -2013 COTTON NEMATODE CONTROL

    E-print Network

    Stuart, Steven J.

    South Carolina Pest Management Handbook for Field Crops - 2013 113 COTTON NEMATODE CONTROL John D AVAILABLE IN SOUTH CAROLINA FOR CONTROL OF NEMATODES. SEE LABELS FOR SPECIFIC SPECIES CONTROLLED BY EACH;South Carolina Pest Management Handbook for Field Crops - 2013 115 NEMATICIDES AVAILABLE IN SOUTH

  4. South Carolina Pest Management Handbook for Field Crops -2014 COTTON NEMATODE CONTROL

    E-print Network

    Duchowski, Andrew T.

    South Carolina Pest Management Handbook for Field Crops - 2014 123 COTTON NEMATODE CONTROL John D pressure. #12;South Carolina Pest Management Handbook for Field Crops - 2014 124 FUMIGANT, GRANULAR, AND LIQUID NEMATICIDES AVAILABLE IN SOUTH CAROLINA FOR CONTROL OF NEMATODES. SEE LABELS FOR SPECIFIC SPECIES

  5. Post-transcriptional gene silencing of root knot-nematode in transformed soybean roots

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant-parasitic nematodes cause about $100 billion in crop losses annually. Root-knot nematodes (RKN; Meloidogyne spp.) are sedentary endoparasites, and the genus has been found on more than 3000 host plant species. In this study four different gene constructs were designed to produce RNA interferen...

  6. Root-Parasitic Nematodes Enhance Soil Microbial Activities and Nitrogen Mineralization

    Microsoft Academic Search

    C. Tu; S. R. Koenning; S. Hu

    2003-01-01

    Obligate root-parasitic nematodes can affect soil microbes positively by enhancing C and nutrient leakage from roots but negatively by restricting total root growth. However, it is unclear how the resulting changes in C availability affect soil microbial activities and N cycling. In a microplot experiment, effects of root-parasitic reniform nematodes (Rotylenchulus reniformis) on soil microbial biomass and activities were examined

  7. A ROOT-KNOT NEMATODE PATHOGENIC TO COCK'S COMB, CELOSIA ARGENTEA L

    Microsoft Academic Search

    S. A. ANWAR; A. ZIA; Q. SHAKEEL

    The presence of root-knot nematode, Meloidogyne incognita was assessed on roots and rhizosphere soil of cock's comb (Celosia argentea L.) planted in 5 lawns located at the campus of University of Agriculture, Faisalabad. The infected plants were stunted with galled and rotted roots. Four fungal pathogens including Fusarium, Pythium, Rhizoctonia and Sclerotia were isolated from nematode-fungal complex infected roots. Plant

  8. Effects of Midas® on Nematodes in Commercial Floriculture Production in Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cut flower producers currently have limited options for nematode control. Four field trials were conducted in 2006 and 2007 to evaluate Midas® (iodomethane:chloropicrin 50:50) for control of root-knot nematodes (Meloidogyne arenaria) on Celosia argentea var. cristata in a commercial floriculture pr...

  9. Impact of the soybean cyst nematode on seedling diseases of sugarbeet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean cyst nematode (SCN; Heterodera glycines) has recently moved into the southern Red River Valley of North Dakota and Minnesota. When sugarbeet is planted into SCN-infested soil, the nematode may attempt to penetrate and establish itself in the sugarbeet roots. Such penetration attempts are lik...

  10. A Bacterial Artificial Chromosome-Based Genetic Linkage Map of the Nematode Pristionchus pacificus

    Microsoft Academic Search

    Jagan Srinivasan; Waltraud Sinz; Christa Lanz; Alexandra Brand; Ramkumar Nandakumar; Gunter Raddatz; Hanh Witte; Heike Keller; Isabel Kipping; Taco Jesse; Jun Millare; Stephan C. Schuster; Ralf J. Sommer

    2002-01-01

    To understand the evolution of developmental processes, nonmodel organisms in the nematodes, insects, and vertebrates are compared with established model systems. Often, these comparisons suffer from the inability to apply sophisticated technologies to these nonmodel species. In the nematode Pristion- chus pacificus, cellular and genetic analyses are used to compare vulva development to that of Caenorhabditis elegans. However, substantial changes

  11. QTLS associated with resistance to soybean cyst nematode: Meta-analysis of QTL locations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soybean cyst nematode (SCN) (Heterodera glycines Ichinohe) is the most important pest of soybean (Glycine max (L.) Merr) in the world. A total of 17 quantitative trait locus (QTL) mapping papers and 62 marker-QTL associations have been reported for resistance to soybean cyst nematode in soybean. C...

  12. REGISTRATION OF CN12 AND CN72 SUGARBEET GERMPLASMS WITH RESISTANCE TO CYST NEMATODE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Resistance to sugar beet cyst nematode in sugarbeet has been elusive and very difficult to fix in a genetically stable manner. Resistance from wide crosses to Beta procumbens conditions near immunity to cyst nematode and has been extensively researched but has been little used because of this meioti...

  13. Field Responses of Bermudagrass and Seashore paspalum Cultivars to Sting and Spiral Nematodes

    PubMed Central

    Pang, Wenjing; Luc, John E.; Crow, William T.; Kenworthy, Kevin E.; Giblin-Davis, Robin M.; McSorley, Robert; Kruse, Jason K.

    2011-01-01

    Belonolaimus longicaudatus and Helicotylenchus spp. are damaging nematode species on bermudagrass (Cynodon spp.) and seashore paspalum (Paspalum vaginatum) in sandy soils of the southeastern United States. Eight bermudagrass and three seashore paspalum cultivars were tested for responses to both nematode species in field plots for two years in Florida. Soil samples were taken every three months and nematode population densities in soil were quantified. Turfgrass aboveground health was evaluated throughout the growing season. Results showed that all bermudagrass cultivars, except TifSport, were good hosts for B. longicaudatus, and all seashore paspalum cultivars were good hosts for H. pseudorobustus. Overall, bermudagrass was a better host for B. longicaudatus while seashore paspalum was a better host for H. pseudorobustus. TifSport bermudagrass and SeaDwarf seashore paspalum cultivars supported the lowest population densities of B. longicaudatus. Seashore paspalum had a higher percent green cover than bermudagrass in the nematode-infested field. Nematode intolerant cultivars were identified. PMID:23430148

  14. Field Responses of Bermudagrass and Seashore paspalum Cultivars to Sting and Spiral Nematodes.

    PubMed

    Pang, Wenjing; Luc, John E; Crow, William T; Kenworthy, Kevin E; Giblin-Davis, Robin M; McSorley, Robert; Kruse, Jason K

    2011-09-01

    Belonolaimus longicaudatus and Helicotylenchus spp. are damaging nematode species on bermudagrass (Cynodon spp.) and seashore paspalum (Paspalum vaginatum) in sandy soils of the southeastern United States. Eight bermudagrass and three seashore paspalum cultivars were tested for responses to both nematode species in field plots for two years in Florida. Soil samples were taken every three months and nematode population densities in soil were quantified. Turfgrass aboveground health was evaluated throughout the growing season. Results showed that all bermudagrass cultivars, except TifSport, were good hosts for B. longicaudatus, and all seashore paspalum cultivars were good hosts for H. pseudorobustus. Overall, bermudagrass was a better host for B. longicaudatus while seashore paspalum was a better host for H. pseudorobustus. TifSport bermudagrass and SeaDwarf seashore paspalum cultivars supported the lowest population densities of B. longicaudatus. Seashore paspalum had a higher percent green cover than bermudagrass in the nematode-infested field. Nematode intolerant cultivars were identified. PMID:23430148

  15. On the Methodology of Nematode Extraction from Field Samples: Baermann Funnel Modifications

    PubMed Central

    Viglierchio, D. R.; Schmitt, Richard V.

    1983-01-01

    Routine quantitative nematode extraction for pest management purposes remains a problem. There is need for more knowledge of the parameters limiting efficiency of the various available methods. Sedimentation rates for several species of nematodes have been confirmed as slow and highly variable and therefore not suitable for quantitative separation of nematodes. Funnel losses with clean and unpitted glassware, whether closed or open stemmed, with or without misting, are negligible so long as misting periods are neither inadequate nor excessive; i.e., approximately a 1.5-min water spray period in a 10-min cycle. Tissue paper used to retain soil, sievings, or other substrate in the funnel extraction can greatly inhibit the passage of nematodes depending upon the tissue properties and the nematode species. PMID:19295830

  16. Molecular analysis of HSP90, a multi-faceted gene involved in the growth and development of free-living and plant-parasitic nematodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plant parasitic nematodes cause in excess of $100 billion of global crop losses each year. Cyst nematodes (Heterodera spp) are endoparasitic root-feeding nematodes, and the soybean cyst nematode (SCN), Heterodera glycines, causes substantial losses in soybean yield in the U.S.A. as well as througho...

  17. Distribution of the entomopathogenic nematodes from La Rioja (Northern Spain).

    PubMed

    Campos-Herrera, Raquel; Escuer, Miguel; Labrador, Sonia; Robertson, Lee; Barrios, Laura; Gutiérrez, Carmen

    2007-06-01

    Entomopathogenic nematodes (EPNs) distribution in natural areas and crop field edges in La Rioja (Northern Spain) has been studied taking into account environmental and physical-chemical soil factors. Five hundred soil samples from 100 sites of the most representative habitats were assayed for the presence of EPNs. The occurrence of EPNs statistically fitted to a negative binomial distribution, which pointed out that the natural distribution of these nematodes in La Rioja was in aggregates. There were no statistical differences (p < or = 0.05) in the abundance of EPNs to environmental and physical-chemical variables, although, there were statistical differences in the altitude, annual mean air temperature and rainfall, potential vegetation series and moisture percentage recovery frequency. Twenty-seven samples from 14 sites were positive for EPNs. From these samples, twenty isolates were identified to a species level and fifteen strains were selected: 11 Steinernema feltiae, two S. carpocapsae and two S. kraussei strains. S. kraussei was isolated from humid soils of cool and high altitude habitats and S. carpocapsae was found to occur in heavy soils of dry and temperate habitats. S. feltiae was the most common species with a wide range of altitude, temperature, rainfall, pH and soil moisture, although this species preferred sandy soils. The virulence of nematode strains were assessed using G. mellonella as insect host, recording the larval mortality percentage and the time to insect die, as well as the number of infective juveniles produced to evaluate the reproductive potential and the time tooks to leave the insect cadaver to determinate the infection cycle length. The ecological trends and biological results are discussed in relationship with their future use as biological control. PMID:17386935

  18. Tangling of Tethered Swimmers: Interactions between Two Nematodes

    NASA Astrophysics Data System (ADS)

    Backholm, Matilda; Schulman, Rafael D.; Ryu, William S.; Dalnoki-Veress, Kari

    2014-09-01

    The tangling of two tethered microswimming worms serving as the ends of "active strings" is investigated experimentally and modeled analytically. C. elegans nematodes of similar size are caught by their tails using micropipettes and left to swim and interact at different separations over long times. The worms are found to tangle in a reproducible and statistically predictable manner, which is modeled based on the relative motion of the worm heads. Our results provide insight into the intricate tangling interactions present in active biological systems.

  19. The mitochondrial genome of the soybean cyst nematode, Heterodera glycines.

    PubMed

    Gibson, Tracey; Farrugia, Daniel; Barrett, Jeff; Chitwood, David J; Rowe, Janet; Subbotin, Sergei; Dowton, Mark

    2011-07-01

    We sequenced the entire coding region of the mitochondrial genome of Heterodera glycines. The sequence obtained comprised 14.9 kb, with PCR evidence indicating that the entire genome comprised a single, circular molecule of approximately 21-22 kb. The genome is the most T-rich nematode mitochondrial genome reported to date, with T representing over half of all nucleotides on the coding strand. The genome also contains the highest number of poly(T) tracts so far reported (to our knowledge), with 60 poly(T) tracts ? 12 Ts. All genes are transcribed from the same mitochondrial strand. The organization of the mitochondrial genome of H. glycines shows a number of similarities compared with Radopholus similis, but fewer similarities when compared with Meloidogyne javanica. Very few gene boundaries are shared with Globodera pallida or Globodera rostochiensis. Partial mitochondrial genome sequences were also obtained for Heterodera cardiolata (5.3 kb) and Punctodera chalcoensis (6.8 kb), and these had identical organizations compared with H. glycines. We found PCR evidence of a minicircular mitochondrial genome in P. chalcoensis, but at low levels and lacking a noncoding region. Such circularised genome fragments may be present at low levels in a range of nematodes, with multipartite mitochondrial genomes representing a shift to a condition in which these subgenomic circles predominate. PMID:21745140

  20. Handmade Cloned Transgenic Piglets Expressing the Nematode Fat-1 Gene

    PubMed Central

    Zhang, Peng; Zhang, Yidi; Dou, Hongwei; Yin, Jingdong; Chen, Yu; Pang, Xinzhi; Vajta, Gabor; Bolund, Lars

    2012-01-01

    Abstract Production of transgenic animals via somatic cell nuclear transfer (SCNT) has been adapted worldwide, but this application is somewhat limited by its relatively low efficiency. In this study, we used handmade cloning (HMC) established previously to produce transgenic pigs that express the functional nematode fat-1 gene. Codon-optimized mfat-1 was inserted into eukaryotic expression vectors, which were transferred into primary swine donor cells. Reverse transcriptase PCR (RT-PCR), gas chromatography, and chromosome analyses were performed to select donor clones capable of converting n-6 into n-3 fatty acids. Blastocysts derived from the clones that lowered the n-6/n-3 ratio to approximately 1:1 were transferred surgically into the uteri of recipients for transgenic piglets. By HMC, 37% (n=558) of reconstructed embryos developed to the blastocyst stage after 7 days of culture in vitro, with an average cell number of 81±36 (n=14). Three recipients became pregnant after 408 day-6 blastocysts were transferred into four naturally cycling females, and a total of 14 live offspring were produced. The nematode mfat-1 effectively lowered the n-6/n-3 ratio in muscle and major organs of the transgenic pig. Our results will help to establish a reliable procedure and an efficient option in the production of transgenic animals. PMID:22686479

  1. Pathogenesis in Pine Wilt Caused by Pinewood Nematode, Bursaphelenchus xylophilus

    PubMed Central

    Myers, Ronald F.

    1988-01-01

    The progression of events in the development of pine wilt disease following the invasion by Bursaphelenchus xylophilus is reviewed from early migration through pine tissues until symptom development on foliage. Disease resistance in pines, especially the hypersensitive reaction that is successful in controlling many potential pests and pathogens, is explored. Pathologies resulting from the activities of pinewood nematode include cortical trails and cavities; formation of cambial gaps and traumatic resin cysts; browning and death of cortex, phloem, cambium, and ray tissues; granulation and shrinkage of cell cytoplasm in rays; and destruction of resin canal epithelial and ray parenchyma cells. Death of parenchyma, production of toxins, and leakage of oleoresins and other material into tracheids are typical of the hypersensitive reaction occurring in pines following migration of small numbers of pinewood nematodes. The hypothesis presented is that a spreading hypersensitive reaction results in some of the observed pathologies and symptoms and eventually causes pine death. The growth-differentiation balance hypothesis is used to help explain predisposition, oleoresin production and toxicity, susceptibility and resistance, and the effects of variation in climate on host pines as related to pinewilt disease. PMID:19290207

  2. The regulation of spermatogenesis and sperm function in nematodes.

    PubMed

    Ellis, Ronald E; Stanfield, Gillian M

    2014-05-01

    In the nematode C. elegans, both males and self-fertile hermaphrodites produce sperm. As a result, researchers have been able to use a broad range of genetic and genomic techniques to dissect all aspects of sperm development and function. Their results show that the early stages of spermatogenesis are controlled by transcriptional and translational processes, but later stages are dominated by protein kinases and phosphatases. Once spermatids are produced, they participate in many interactions with other cells - signals from the somatic gonad determine when sperm activate and begin to crawl, signals from the female reproductive tissues guide the sperm, and signals from sperm stimulate oocytes to mature and be ovulated. The sperm also show strong competitive interactions with other sperm and oocytes. Some of the molecules that mediate these processes have conserved functions in animal sperm, others are conserved proteins that have been adapted for new roles in nematode sperm, and some are novel proteins that provide insights into evolutionary change. The advent of new techniques should keep this system on the cutting edge of research in cellular and reproductive biology. PMID:24718317

  3. The regulation of spermatogenesis and sperm function in nematodes

    PubMed Central

    Ellis, Ronald E.; Stanfield, Gillian M.

    2014-01-01

    In the nematode C. elegans, both males and self-fertile hermaphrodites produce sperm. As a result, researchers have been able to use a broad range of genetic and genomic techniques to dissect all aspects of sperm development and function. Their results show that the early stages of spermatogenesis are controlled by transcriptional and translational processes, but later stages are dominated by protein kinases and phosphatases. Once spermatids are produced, they participate in many interactions with other cells — signals from the somatic gonad determine when sperm activate and begin to crawl, signals from the female reproductive tissues guide the sperm, and signals from sperm stimulate oocytes to mature and be ovulated. The sperm also show strong competitive interactions with other sperm and oocytes. Some of the molecules that mediate these processes have conserved functions in animal sperm, others are conserved proteins that have been adapted for new roles in nematode sperm, and some are novel proteins that provide insights into evolutionary change. The advent of new techniques should keep this system on the cutting edge of research in cellular and reproductive biology. PMID:24718317

  4. Activity of doramectin against nematode endoparasites of cattle.

    PubMed

    Jones, R M; Logan, N B; Weatherley, A J; Little, A S; Smothers, C D

    1993-07-01

    A series of 28 controlled anthelmintic studies, involving 634 cattle, was conducted throughout North America and Europe to evaluate the efficacy of doramectin against a broad range of gastrointestinal parasitic nematode species and lungworms in naturally and experimentally infected animals. Within each study, one or two groups were treated with doramectin at 200 micrograms kg-1 and another group received no drug treatment. Worm burdens were estimated by standardised techniques, and efficacy assessed on reduction of worm burdens in doramectin-treated animals. Doramectin was at least 99.6% effective (P < 0.0002) in eliminating the immature and adult stages of the following 14 species of nematodes: Ostertagia ostertagi (including inhibited), Ostertagia lyrata, Haemonchus placei, Trichostrongylus axei, Trichostrongylus colubriformis, Cooperia oncophora (including inhibited), Cooperia pectinata, Cooperia punctata, Cooperia spatulata, Cooperia surnabada, Bunostomum phlebotomum, Strongyloides papillosus, Oesophagostomum radiatum and Dictyocaulus viviparus. Efficacy against adult Trichostrongylus longispicularis, Nematodirus spathiger and Trichuris spp. was 93.1%, 96.5% and 94.6%, respectively. Efficacies against adult and fourth-stage larvae of Nematodirus helvetianus, the dose-limiting species, were 73.3% and 75.5%, respectively. PMID:8236735

  5. Factors affecting population trends of plant-parasitic nematodes on rangeland grasses.

    PubMed

    Griffin, G D; Asay, K H; Horton, W H

    1996-03-01

    The effects of environmental conditions on population trends of plant-parasitic nematodes were studied in experimental plots of five wheatgrasses in the western Utah desert. In a 3-year (1984-86) field study, soil water and temperature affected the population trends of the ectoparasites, Tylenchorhynchus acutoides and Xiphinema americanum, and the migratory endoparasite, Pratylenchus neglectus, on Fairway crested wheatgrass, Agropyron cristatum; 'Hycrest' crested wheatgrass, A. cristatum X A. desertorura; 'Rosana' western wheatgrass, Pascopyrum smithii; 'Oahe' intermediate wheatgrass, Thinopyrum intermedium; and RS-1 hybrid (Elytrigia repens X Pseudoroegneria spicata). The largest soil populations of these nematode species were collected in 1984 under good plant-growth conditions. A reduction in nematode populations occurred in 1985 and 1986, possibly because of low soil-water conditions. There was a positive relationship between high soil water and maximum population densities of T. acutoides in the spring and fall of 1984, and between low soil water and minimum population densities of the nematode in 1985 and 1986. Pratylenchus neglectus populations were affected by soil water, although to a lesser degree than the ectoparasitic nematodes. Population densities of the three nematode species were significantly lower in the drier years of 1985 and 1986 than in 1984. Nematode populations were greater at the lower soil depths in the fall than in the spring or summer. PMID:19277352

  6. Effect of Host Age and Nematode Strain on Susceptibility of Spodoptera frugiperda to Steinernema feltiae

    PubMed Central

    Fuxa, James R.; Richter, Arthur R.; Acudelo-Silva, Fernando

    1988-01-01

    Median lethal concentrations (LC??) were determined for four nematode populations (two strains of Steinernema feltiae, a S. feltiae hybrid, and S. bibionis) against fifth-instar fall armyworm (Spodoptera frugiperda) larvae and for the most virulent of these nematodes against different instars and stages of the insect. Based on lack of overlap of 95% fiducial limits, there were significant differences in virulence among the four nematodes. The LC?? ranged from 7.6 to 33.3 nematodes/ 0.7 ml water, and slopes of the log dose-probit regression lines were similar except for the S. feltiae All strain. First-instar fall armyworms suffered virtually 100% mortality from the S. feltiae Mexican strain at 1.0 nematode/0.7 ml, and LC?? were 2.3 and 7.9 nematodes/0.7 ml in third-instar and fifth-instar larvae, respectively. Pupae had 7-20% mortality at doses ranging from 30 to 60 nematodes/0.7 ml. PMID:19290189

  7. Interactions of concomitant species of nematodes and Fusarium oxysporum f. sp. vasinfectum on cotton.

    PubMed

    Yang, H; Powell, N T; Barker, K R

    1976-01-01

    Meloidogyne incognita, Hoplolaintus galeatus, and North Carolina and Georgia populations of Belonolaimus longicaudatus were introduced singly and in various combinations with Fusarium oxysporum f. sp. vasinfectum on wilt-susceptible 'Rowden' cotton. Of all the nematodes, the combination of the N. C. population of B. longicaudatus with Fusarium promoted greatest wilt development. H. galeatus had no effect on wilt. With Fusarium plus M. incognito or B. longicaudatus, high nematode levels promoted greater wilt than low levels. The combination of either population of B. longicaudatus with M. incognita and Fusarium induced greater wilt development than comparable inoculum densities of either nematode alone or where H. galeatus was substituted for either of these nematodes. Nematode reproduction was inversely related to wilt development. Without Fusarium, however, the high inoculum level resulted in greater reproduction of all nematode species on cotton. Combining M. incognita with B. longicaudatus or H. galeatus gave mutually depressive effects on final nematode populations. The interactions of H. gateatus with B. longicaudatus varied with two populations of the latter. PMID:19308201

  8. Generation of transgenic plantain (Musa spp.) with resistance to plant pathogenic nematodes.

    PubMed

    Roderick, Hugh; Tripathi, Leena; Babirye, Annet; Wang, Dong; Tripathi, Jaindra; Urwin, Peter E; Atkinson, Howard J

    2012-10-01

    Plant parasitic nematodes impose a severe constraint on plantain and banana productivity; however, the sterile nature of many cultivars precludes conventional breeding for resistance. Transgenic plantain cv. Gonja manjaya (Musa AAB) plants, expressing a maize cystatin that inhibits nematode digestive cysteine proteinases and a synthetic peptide that disrupts nematode chemoreception, were assessed for their ability to resist nematode infection. Lines were generated that expressed each gene singly or both together in a stacked defence. Nematode challenge with a single species or a mixed population identified 10 lines with significant resistance. The best level of resistance achieved against the major pest species Radopholus similis was 84% ± 8% for the cystatin, 66% ± 14% for the peptide and 70% ± 6% for the dual defence. In the mixed population, trial resistance was also demonstrated to Helicotylenchus multicinctus. A fluorescently labelled form of the chemodisruptive peptide underwent retrograde transport along certain sensory dendrites of R. similis as required to disrupt chemoreception. The peptide was degraded after 30 min in simulated intestinal fluid or boiling water and after 1 h in nonsterile soil. In silico sequence analysis suggests that the peptide is not a mammalian antigen. This work establishes the mode of action of a novel nematode defence, develops the evidence for its safe and effective deployment against multiple nematode species and identifies transgenic plantain lines with a high level of resistance for a proposed field trial. PMID:22435592

  9. Nematode assemblages from the Kandalaksha Depression (White Sea, 251-288 m water depth)

    NASA Astrophysics Data System (ADS)

    Miljutin, Dmitry M.; Miljutina, Maria A.; Tchesunov, Alexei V.; Mokievsky, Vadim O.

    2014-03-01

    The shallow-water nematodes of the White Sea are relatively well studied; however, information on the nematode fauna inhabiting the deepest part of this sea is very scarce. The composition of the nematode assemblages (at species and genus level) was studied in samples collected during four sampling occasions in the deepest part of the Kandalaksha Depression (the White Sea) in July 1998, October 1998, May 1999, and November 1999. Samples were collected from a depth of 251-288 m with the aid of a multicorer. In total, 59 nematode morphotypes belonging to 37 genera and 18 families were distinguished. The genera Sabatieria and Filipjeva dominated at all stations, followed by Aponema, Desmoscolex, and Quadricoma. The composition of the dominant genera can be considered typical for this depth range in temperate and Arctic waters, although Filipjeva and Aponema were among the dominant genera for the first time. The most abundant species were Sabatieria ornata, Aponema bathyalis, and Filipjeva filipjevi. In general, diversity of the nematode assemblages was lower than in the temperate and Arctic continental shelf and slope with reduced evenness and species richness. The evenness of nematode assemblages and other diversity indices decreased with increasing sediment depth. Based on the valid species and genera recorded, the nematode fauna of the Kandalaksha Depression showed a higher resemblance to that found in the shallow waters of Kandalaksha Bay.

  10. Nematode and Arthropod Genomes Provide New Insights into the Evolution of Class 2 B1 GPCRs

    PubMed Central

    Cardoso, João C. R.; Félix, Rute C.; Power, Deborah M.

    2014-01-01

    Nematodes and arthropods are the most speciose animal groups and possess Class 2 B1 G-protein coupled receptors (GPCRs). Existing models of invertebrate Class 2 B1 GPCR evolution are mainly centered on Caenorhabditis elegans and Drosophila melanogaster and a few other nematode and arthropod representatives. The present study reevaluates the evolution of metazoan Class 2 B1 GPCRs and orthologues by exploring the receptors in several nematode and arthropod genomes and comparing them to the human receptors. Three novel receptor phylogenetic clusters were identified and designated cluster A, cluster B and PDF-R-related cluster. Clusters A and B were identified in several nematode and arthropod genomes but were absent from D. melanogaster and Culicidae genomes, whereas the majority of the members of the PDF-R-related cluster were from nematodes. Cluster A receptors were nematode and arthropod-specific but shared a conserved gene environment with human receptor loci. Cluster B members were orthologous to human GCGR, PTHR and Secretin members with which they probably shared a common origin. PDF-R and PDF-R related clusters were present in representatives of both nematodes and arthropods. The results of comparative analysis of GPCR evolution and diversity in protostomes confirm previous notions that C. elegans and D. melanogaster genomes are not good representatives of nematode and arthropod phyla. We hypothesize that at least four ancestral Class 2 B1 genes emerged early in the metazoan radiation, which after the protostome-deuterostome split underwent distinct selective pressures that resulted in duplication and deletion events that originated the current Class 2 B1 GPCRs in nematode and arthropod genomes. PMID:24651821

  11. Nematode and arthropod genomes provide new insights into the evolution of class 2 B1 GPCRs.

    PubMed

    Cardoso, João C R; Félix, Rute C; Power, Deborah M

    2014-01-01

    Nematodes and arthropods are the most speciose animal groups and possess Class 2 B1 G-protein coupled receptors (GPCRs). Existing models of invertebrate Class 2 B1 GPCR evolution are mainly centered on Caenorhabditis elegans and Drosophila melanogaster and a few other nematode and arthropod representatives. The present study reevaluates the evolution of metazoan Class 2 B1 GPCRs and orthologues by exploring the receptors in several nematode and arthropod genomes and comparing them to the human receptors. Three novel receptor phylogenetic clusters were identified and designated cluster A, cluster B and PDF-R-related cluster. Clusters A and B were identified in several nematode and arthropod genomes but were absent from D. melanogaster and Culicidae genomes, whereas the majority of the members of the PDF-R-related cluster were from nematodes. Cluster A receptors were nematode and arthropod-specific but shared a conserved gene environment with human receptor loci. Cluster B members were orthologous to human GCGR, PTHR and Secretin members with which they probably shared a common origin. PDF-R and PDF-R related clusters were present in representatives of both nematodes and arthropods. The results of comparative analysis of GPCR evolution and diversity in protostomes confirm previous notions that C. elegans and D. melanogaster genomes are not good representatives of nematode and arthropod phyla. We hypothesize that at least four ancestral Class 2 B1 genes emerged early in the metazoan radiation, which after the protostome-deuterostome split underwent distinct selective pressures that resulted in duplication and deletion events that originated the current Class 2 B1 GPCRs in nematode and arthropod genomes. PMID:24651821

  12. Soil Nematode Responses to Increases in Nitrogen Deposition and Precipitation in a Temperate Forest

    PubMed Central

    Sun, Xiaoming; Zhang, Xiaoke; Zhang, Shixiu; Dai, Guanhua; Han, Shijie; Liang, Wenju

    2013-01-01

    The environmental changes arising from nitrogen (N) deposition and precipitation influence soil ecological processes in forest ecosystems. However, the corresponding effects of environmental changes on soil biota are poorly known. Soil nematodes are the important bioindicator of soil environmental change, and their responses play a key role in the feedbacks of terrestrial ecosystems to climate change. Therefore, to explore the responsive mechanisms of soil biota to N deposition and precipitation, soil nematode communities were studied after 3 years of environmental changes by water and/or N addition in a temperate forest of Changbai Mountain, Northeast China. The results showed that water combined with N addition treatment decreased the total nematode abundance in the organic horizon (O), while the opposite trend was found in the mineral horizon (A). Significant reductions in the abundances of fungivores, plant-parasites and omnivores-predators were also found in the water combined with N addition treatment. The significant effect of water interacted with N on the total nematode abundance and trophic groups indicated that the impacts of N on soil nematode communities were mediated by water availability. The synergistic effect of precipitation and N deposition on soil nematode communities was stronger than each effect alone. Structural equation modeling suggested water and N additions had direct effects on soil nematode communities. The feedback of soil nematodes to water and nitrogen addition was highly sensitive and our results indicate that minimal variations in soil properties such as those caused by climate changes can lead to severe changes in soil nematode communities. PMID:24324794

  13. Multichannel microfluidic chip for rapid and reliable trapping and imaging plant-parasitic nematodes

    NASA Astrophysics Data System (ADS)

    Amrit, Ratthasart; Sripumkhai, Witsaroot; Porntheeraphat, Supanit; Jeamsaksiri, Wutthinan; Tangchitsomkid, Nuchanart; Sutapun, Boonsong

    2013-05-01

    Faster and reliable testing technique to count and identify nematode species resided in plant roots is therefore essential for export control and certification. This work proposes utilizing a multichannel microfluidic chip with an integrated flow-through microfilter to retain the nematodes in a trapping chamber. When trapped, it is rather simple and convenient to capture images of the nematodes and later identify their species by a trained technician. Multiple samples can be tested in parallel using the proposed microfluidic chip therefore increasing number of samples tested per day.

  14. Nematicides and Nonconventional Soil Amendments in the Management of Root-Knot Nematode on Cotton

    PubMed Central

    Jorgenson, E. C.

    1984-01-01

    Granular and liquid commercial humates, with micronutrients, and a microbial fermentation product were compared in several combinations with nematicides for their effects on cotton lint yield and root-knot nematode suppression. Fumigant nematicides effectively reduced cotton root galling caused by root-knot nematodes, and cotton lint yields increased. Organophosphates and carbamates were not effective. Occasionally, cotton lint yields were increased or maintained with combination treatments o f humates, micronutrients, and a microbial fermentation product, but galling o f cotton roots by root-knot nematodes was usually not reduced by these treatments. PMID:19295893

  15. Perspectives on the behavior of entomopathogenic nematodes from dispersal to reproduction: traits contributing to nematode fitness and biocontrol efficacy.

    PubMed

    Griffin, Christine T

    2012-06-01

    The entomopathogenic nematodes (EPN) Heterorhabditis and Steinernema are widely used for the biological control of insect pests and are gaining importance as model organisms for studying parasitism and symbiosis. In this paper recent advances in the understanding of EPN behavior are reviewed. The "foraging strategy" paradigm (distinction between species with ambush and cruise strategies) as applied to EPN is being challenged and alternative paradigms proposed. Infection decisions are based on condition of the potential host, and it is becoming clear that already-infected and even long-dead hosts may be invaded, as well as healthy live hosts. The state of the infective juvenile (IJ) also influences infection, and evidence for a phased increase in infectivity of EPN species is mounting. The possibility of social behavior - adaptive interactions between IJs outside the host - is discussed. EPNs' symbiotic bacteria (Photorhabdus and Xenorhabdus) are important for killing the host and rendering it suitable for nematode reproduction, but may reduce survival of IJs, resulting in a trade-off between survival and reproduction. The symbiont also contributes to defence of the cadaver by affecting food-choice decisions of insect and avian scavengers. I review EPN reproductive behavior (including sperm competition, copulation and evidence for attractive and organizational effects of pheromones), and consider the role of endotokia matricida as parental behavior exploited by the symbiont for transmission. PMID:23482343

  16. Isolation of whole esophageal gland cells from plant-parasitic nematodes for transcriptome analyses and effector identification.

    PubMed

    Maier, Tom R; Hewezi, Tarek; Peng, Jiqing; Baum, Thomas J

    2013-01-01

    Esophageal glands of plant-parasitic nematodes are highly specialized cells whose gene expression products include secreted effector proteins, which govern nematode parasitism of host plants. Therefore, elucidating the transcriptomes of esophageal glands with the goal of identifying nematode effectors is a promising avenue to understanding nematode parasitism and its evolutionary origins as well as to devising nematode control strategies. We have developed a method to separate and isolate individual esophageal gland cells from multiple species of plant-parasitic nematodes while preserving RNA quality. We have used such isolated gland cells for transcriptome analysis via high-throughput DNA sequencing. This method relies on the differential histochemical staining of the gland cells after homogenization of phytonematode tissues. Total RNA was extracted from whole gland cells isolated from eight different plant-parasitic nematode species. To validate this approach, the isolated RNA from three plant-parasitic nematode species-Globodera rostochiensis, Pratylenchus penetrans, and Radopholus similis-was amplified, gel purified, and used for 454 sequencing. We obtained 456,801 total reads with an average read length of 409 bp. Sequence analyses revealed the presence of homologs of previously known nematode effectors in these libraries, thus validating our approach. These data provide compelling evidence that this technical advance can be used to relatively easily and expediently discover effector repertoires of plant-parasitic nematodes. PMID:22876962

  17. Increased response to cadmium and Bacillus thuringiensis maize toxicity in the snail Helix aspersa infected by the nematode Phasmarhabditis hermaphrodita.

    PubMed

    Kramarz, Paulina E; de Vaufleury, Annette; Zygmunt, Piotr M S; Verdun, Cyrille

    2007-01-01

    To determine the effect of nematode infection on the response of snails to selected toxins, we infected Helix aspersa with 0-, 0.25-, 1-, or 4-fold the recommended field dose of a commercial nematode application for agricultural use. In the first experiment, the snails also were exposed to cadmium via food and soil at concentrations of 0, 30, 60, 120, or 240 mg/kg in a full-factorial design. In the second experiment, snails were infected with nematodes and also fed either Bt (expressing Bacillus thuringiensis toxin) maize or non-Bt maize. The snails were weighed at the beginning and end (after four weeks) of the experiments, and mortality was checked daily. Neither exposure of snails to nematodes nor exposure of snails to cadmium or Bt toxin affected the survival rates of snails. The number of dead snails was highest for combinations of nematode treatments with cadmium concentrations of 120 and 240 mg/kg. In both experiments (Bt and cadmium), the growth rate decreased with increasing nematode dose. The Bt maize was not harmful to the snails in the absence of nematodes, but infected snails grew faster when fed non-Bt maize. The growth rate of snails exposed to cadmium decreased with exposure to increasing Cd concentrations and differed significantly between the no-nematode treatment and the treatments with nematode doses of one- and fourfold the recommended field dose. Snails treated with the highest dose of nematodes accumulated the highest cadmium concentrations. PMID:17269462

  18. Controlling nematodes in dairy calves using targeted selective treatments.

    PubMed

    O'Shaughnessy, J; Earley, B; Mee, J F; Doherty, M L; Crosson, P; Barrett, D; de Waal, T

    2015-04-30

    With increasing concerns of anthelmintic resistance in cattle nematode populations worldwide, there is a need to explore alternative approaches to nematode control. One alternative approach is the use of targeted selective treatments (TST) where only individual animals are treated instead of the entire group. This study reports the findings of a TST approach in dairy calves conducted over their first grazing season (FGS) to control both gastrointestinal nematode and lungworm challenge. Ninety-six calves with an initial mean (s.d.) age and live weight of 130 (28.3) days and 120 (23.6)kg, respectively, were randomised by breed, age and live weight to one of two treatments; Control (n=24; ×2) and TST (n=24; ×2). Control calves were treated three times at pasture with ivermectin by subcutaneous injection. Individual calves in the TST group were treated at pasture with ivermectin when one of the following thresholds was met: (1) positive for lungworm larvae using the modified Baermann technique or (2) positive or negative for lungworm larvae using the modified Baermann technique with plasma pepsinogen concentration (PP) ? two international units of tyrosine/litre and faecal egg count (FEC) ? 200 strongyle eggs per gram of faeces. Calves were rotationally grazed from July 3rd 2012 (day 0) to November 2nd 2012 (day 122) when calves were housed. Calves were weighed and sampled (blood and faecal) every three weeks. There was an effect of treatment and time on both FEC [treatment (P=0.023), time (P<0.001)] and PP [treatment (P=0.002), time (P<0.001)]. Both FEC and PP were higher in TST calves. There was a 50% reduction in anthelmintic use in TST calves compared to control calves. Clinical signs of lungworm infection, confirmed by the modified Baermann technique, were evident in TST calves on days 62 and 63 of the study. The average daily live weight gain for control and TST calves was 0.50 (0.02)kg day(-1) and 0.47 (0.03)kg day(-1), respectively (P=0.41). Thus, performance in dairy calves can potentially be maintained with fewer anthelmintic treatments but farmers need to be vigilant of the challenge posed by lungworm. Any future approach into the use of TST in FGS calves must take into consideration the relative importance of lungworm as a pathogen. PMID:25770853

  19. The Alkaloid Compound Harmane Increases the Lifespan of Caenorhabditis elegans during Bacterial Infection, by Modulating the Nematode’s Innate Immune Response

    PubMed Central

    Marinus, Martin G.; Xu, Tao; Struve, Carsten; Krogfelt, Karen A.; Løbner-Olesen, Anders

    2013-01-01

    The nematode Caenorhabditis elegans has in recent years been proven to be a powerful in vivo model for testing antimicrobial compounds. We report here that the alkaloid compound Harmane (2-methyl-?-carboline) increases the lifespan of nematodes infected with a human pathogen, the Shiga toxin-producing Escherichia coli O157:H7 strain EDL933 and several other bacterial pathogens. This was shown to be unrelated to the weak antibiotic effect of Harmane. Using GFP-expressing E. coli EDL933, we showed that Harmane does not lower the colonization burden in the nematodes. We also found that the expression of the putative immune effector gene F35E12.5 was up-regulated in response to Harmane treatment. This indicates that Harmane stimulates the innate immune response of the nematode; thereby increasing its lifespan during bacterial infection. Expression of F35E12.5 is predominantly regulated through the p38 MAPK pathway; however, intriguingly the lifespan extension resulting from Harmane was higher in p38 MAPK-deficient nematodes. This indicates that Harmane has a complex effect on the innate immune system of C. elegans. Harmane could therefore be a useful tool in the further research into C. elegans immunity. Since the innate immunity of C. elegans has a high degree of evolutionary conservation, drugs such as Harmane could also be possible alternatives to classic antibiotics. The C. elegans model could prove to be useful for selection and development of such drugs. PMID:23544153

  20. [Community characteristics of soil nematode in Abies georgei var. smithii forest in Sejila Mountain of Tibet, Southwest China].

    PubMed

    Xue, Hui-Ying; Luo, Da-Qing; Yu, Bao-Zheng

    2012-12-01

    In order to understand the present status of nematode diversity in soil ecosystem of Abies georgei var. smithii forest, the typical forest type in subalpine zone of southeastern Tibet, an investigation was made on the nematode community in different soil layers of 0-30 cm depth from the summer, 2010 to the spring, 2011. The nematode individual density, diversity index, and trophic group index were taken to analyze the composition and structural characteristics of the soil nematode community. A total of 7915 soil nematodes belonging to 2 classes, 6 orders, 38 families, and 67 genera were collected by shallow dish method. The nematode individual density was averagely 620 nematodes x 100 g(-1) dry soil, and the nematode individuals in surface soil layer (0-5 cm) accounted for 56.9% of the total, indicating the obvious surface gathering characteristics of the nematode community. Tylencholaimus, Helicotylenchus, and Plectus were the dominant genus. Plant-parasite nematode was the dominant trophic group, while fungi-feeding nematode had the largest proportion among the non plant-parasite nematodes. Soil organic matter was mainly decomposed by fungi. The ANOVA analysis indicated that there were no significant differences in the Shannon, Pielou, Margalef, and Simpson indices of soil nematode community among different seasons. The Pielou index had no significant difference among different soil layers, while the differences of Shannon, Margalef, and Simpson indices tended to be increased with increasing soil depth. It was concluded that the A. georgei var. smithii forest ecosystem in Sejila Mountain had a high maturity, with strong resistance to environment disturbances. PMID:23479883

  1. Comparison of endemic and exotic entomopathogenic nematode species for control of Colorado potato beetle (Coleoptera: Chrysomelidae).

    PubMed

    Berry, R E; Liu, J; Reed, G

    1997-12-01

    We compared the efficacy of 2 endemic strains of entomopathogenic nematodes isolated from Hermiston, OR, with that of 3 exotic nematode species for control of Colorado potato beetle, Leptinotarsa decemlineata (Say). In laboratory experiments, the exotic Heterorhabditis species were more pathogenic to Colorado potato beetle than were the endemic Heterorhabditis strains. Exotic Steinernema species were less pathogenic to Colorado potato beetle than the exotic Heterorhabditis species. No Colorado potato beetle adults emerged from soil treated with H. marelatus Liu & Berry, a new species collected from Seaside, OR. Nematode pathogenicity was detected up to 14 wk after application in Galleria mellonella (L.) in soil taken from field plots treated with endemic and exotic nematode species. PMID:9461847

  2. The use of nematodes in assessing ecological conditions in shallow waters surrounding a Mediterranean harbour facility

    NASA Astrophysics Data System (ADS)

    Losi, V.; Ferrero, T. J.; Moreno, M.; Gaozza, L.; Rovere, A.; Firpo, M.; Marques, J. C.; Albertelli, G.

    2013-09-01

    The spatial distribution and structure of nematode assemblages in the area surrounding the harbour of Vado Ligure (Savona, NW Mediterranean) were studied in relation to the influence of natural and anthropogenic environmental factors. Stations were selected following an "anthropogenic gradient" from sites located near the city centre and its harbour to more pristine and distant sites. Sediment quality was determined by considering both sediment granulometric and chemical parameters (hydrocarbons, heavy metals, total organic matter, proteins, carbohydrates) as well as nematode abundance, diversity, life strategies, trophic structure and assemblage composition. A high correlation between environmental characteristics and the nematode response was found. On the basis of the comparison of these results, which identified three distinct sub-areas associated with different levels of environmental quality, a set of nematode indicator genera was selected for the future evaluation of quality status.

  3. Transcriptional profiling of trait deterioration in the insect pathogenic nematode Heterorhabditis bacteriophora

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trait deterioration under laboratory conditions has been widely documented in the entomopathogenic nematode (EPN) Heterorhabditis bacteriophora (Hb) but the specific mechanisms behind these genetic processes remain unclear. This research investigates the molecular mechanisms of trait deterioration ...

  4. Potential of Foliar, Dip, and Injection Applications of Avermectins for Control of Plant-Parasitic Nematodes

    PubMed Central

    Jansson, Richard K.; Rabatin, Susan

    1998-01-01

    Studies were conducted to determine the potential of two avermectin compounds, abamectin and emamectin benzoate, for controlling plant-parasitic nematodes when applied by three methods: foliar spray, root dip, and pseudostem injection. Experiments were conducted against Meloidogyne incognita on tomato, M. javanica on banana, and Radopholus similis on banana. Foliar applications of both avermectins to banana and tomato were not effective for controlling any of the nematodes evaluated. Root dips of banana and tomato were moderately effective for controlling M. incognita on tomato and R. similis on banana. Injections (1 ml) of avermectins into banana pseudostems were effective for controlling M. javanica and R similis, and were comparable to control achieved with a conventional chemical nematicide, fenamiphos. Injections of 125 to 2,000 ?g/plant effectively controlled one or both nematodes on banana; abamectin was more effective than emamectin benzoate for controlling nematodes. PMID:19274200

  5. Use of nematodes and insecticides for postharvest control of navel orangeworm (Amyelois transitella)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In previous research the feasibility of two different large scale nematode (Steinernema carpoapsae) application methods were evaluated, application by herbicide sprayer and application through the irrigation system. Application through the irrigation system, chemigation, was chosen for follow up exp...

  6. Molecular networks associated with host resistance to gastrointestional nematodes in cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Parasitism by gastrointestinal nematodes is a disease severely affecting productivity in ruminants. To unravel mechanisms of host resistance to parasitic infection, we characterized the jejunal transcriptome of the cattle populations displaying resistance phenotypes in response to experimental Coope...

  7. Molecular phylogenetics and the evolution of host plant associations in the nematode genus Fergusobia (Tylenchida: Fergusobiinae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fergusobia nematodes (Tylenchida: Fergusobiinae) and Fergusonina flies (Diptera: Fergusoninidae) are mutualists that develop together in galls formed in meristematic tissues of many species of the plant family Myrtaceae in Australasia. Evolutionary relationships of Fergusobia species were inferred f...

  8. Development and chromosome mechanics in nematodes: Results from IML-1

    NASA Astrophysics Data System (ADS)

    Nelson, G. A.; Schubert, W. W.; Kazarians, G. A.; Richards, G. F.

    1994-08-01

    A subset of the Caenorhabditis elegans nematodes flown aboard Biorack on IML-1 was analyzed for the fidelity of development and the mechanics of chromosomes at meiosis. To assess meiosis, mutant worms marked at two linked or unlinked loci were inoculated as heterozygous hermaphrodites and allowed to self fertilize. Mendelian segregation ratios and recombination frequency were measured for offspring produced at 1XG or in microgravity. To assess development, worms and embryos were fixed and stained with the DNA dye, DAPI, or antibodies specific for antigens expressed in germ cells, pharyngeal and body wall muscles, and gut cells. The distribution of cytoplasmic determinants, cell nuclei counts and positions were scored to assess symmetry relations and anatomical features.

  9. Scanning electron microscopy in nematode-induced giant transfer cells.

    PubMed

    Jones, M G; Dropkin, V H

    1976-01-01

    A study of giant cells induced by the root-knot nematode, Meloidogyne incognita, in roots of Impatiens balsamina was made by scanning electron microscopy. The cytoplasmic contents of giant cells were removed by a procedure based on KOH digestion, to reveal inner wall structure. Wall ingrowths typical of transfer cells are present in giant cells from six days onwards after induction. They develop on walls adjacent to vascular tissues, and their distribution and development was examined. Pit fields contianing plasmodesmata become elaborated in walls between giant cells, but pit fields are lost between giant cells and cells outside them. The distribution of plasmodesmata in pit fields suggests that de novo formation of plasmodesmata occurs in walls between giant cells. Various aspects of giant cell formation and function are discussed and wall ingrowth development is compared in giant cells and normal transfer cells. PMID:1001022

  10. Radiation effects in nematodes: results from IML-1 experiments.

    PubMed

    Nelson, G A; Schubert, W W; Kazarians, G A; Richards, G F; Benton, E V; Benton, E R; Henke, R

    1994-10-01

    The nematode Caenorhabditis elegans was exposed to natural space radiation using the ESA Biorack facility aboard Spacelab on International Microgravity Laboratory 1, STS-42. For the major experimental objective dormant animals were suspended in buffer or on agar or immobilized next to CR-39 plastic nuclear track detectors to correlate fluence of HZE particles with genetic events. This configuration was used to isolate mutations in a set of 350 essential genes as well as in the unc-22 structural gene. From flight samples 13 mutants in the unc-22 gene were isolated along with 53 lethal mutations from autosomal regions balanced by a translocation eT1(III;V). Preliminary analysis suggests that mutants from worms correlated with specific cosmic ray tracks may have a higher proportion of rearrangements than those isolated from tube cultures on a randomly sampled basis. Right sample mutation rate was approximately 8-fold higher than ground controls which exhibited laboratory spontaneous frequencies. PMID:11540032

  11. Radiation effects in nematodes: Results from IML-1 experiments

    NASA Technical Reports Server (NTRS)

    Nelson, G. A.; Schubert, W. W.; Kazarians, G. A.; Richards, G. F.; Benton, E. V.; Benton, E. R.; Henke, R.

    1994-01-01

    The nematode Caenorhabditis elegans was exposed to natural space radiation using the ESA biorack facility aboard Spacelab on International Microgravity Laboratory 1, STS-42. For the major experimental objective dormant animals were suspended in buffer or on agar or immobilized next to CR-39 plastic nuclear track detectors to correlate fluence of HZE particles with genetic events. This configuration was used to isolate mutations in a set of 350 essential genes as well as in the unc-22 structural gene. From flight samples 13 mutants in the unc-22 gene were isolated along with 53 lethal mutations from autosomal regions balanced by a translocation eT1(III;V). Preliminary analysis suggests that mutants from worms correlated with specific cosmic ray tracks may have a higher proportion of rearrangements than those isolated from tube cultures on a randomly sampled basis. Flight sample mutation rate was approximately 8-fold higher than ground controls which exhibited laboratory spontaneous frequencies.

  12. nGASP - the nematode genome annotation assessment project

    SciTech Connect

    Coghlan, A; Fiedler, T J; McKay, S J; Flicek, P; Harris, T W; Blasiar, D; Allen, J; Stein, L D

    2008-12-19

    While the C. elegans genome is extensively annotated, relatively little information is available for other Caenorhabditis species. The nematode genome annotation assessment project (nGASP) was launched to objectively assess the accuracy of protein-coding gene prediction software in C. elegans, and to apply this knowledge to the annotation of the genomes of four additional Caenorhabditis species and other nematodes. Seventeen groups worldwide participated in nGASP, and submitted 47 prediction sets for 10 Mb of the C. elegans genome. Predictions were compared to reference gene sets consisting of confirmed or manually curated gene models from WormBase. The most accurate gene-finders were 'combiner' algorithms, which made use of transcript- and protein-alignments and multi-genome alignments, as well as gene predictions from other gene-finders. Gene-finders that used alignments of ESTs, mRNAs and proteins came in second place. There was a tie for third place between gene-finders that used multi-genome alignments and ab initio gene-finders. The median gene level sensitivity of combiners was 78% and their specificity was 42%, which is nearly the same accuracy as reported for combiners in the human genome. C. elegans genes with exons of unusual hexamer content, as well as those with many exons, short exons, long introns, a weak translation start signal, weak splice sites, or poorly conserved orthologs were the most challenging for gene-finders. While the C. elegans genome is extensively annotated, relatively little information is available for other Caenorhabditis species. The nematode genome annotation assessment project (nGASP) was launched to objectively assess the accuracy of protein-coding gene prediction software in C. elegans, and to apply this knowledge to the annotation of the genomes of four additional Caenorhabditis species and other nematodes. Seventeen groups worldwide participated in nGASP, and submitted 47 prediction sets for 10 Mb of the C. elegans genome. Predictions were compared to reference gene sets consisting of confirmed or manually curated gene models from WormBase. The most accurate gene-finders were 'combiner' algorithms, which made use of transcript- and protein-alignments and multi-genome alignments, as well as gene predictions from other gene-finders. Gene-finders that used alignments of ESTs, mRNAs and proteins came in second place. There was a tie for third place between gene-finders that used multi-genome alignments and ab initio gene-finders. The median gene level sensitivity of combiners was 78% and their specificity was 42%, which is nearly the same accuracy as reported for combiners in the human genome. C. elegans genes with exons of unusual hexamer content, as well as those with many exons, short exons, long introns, a weak translation start signal, weak splice sites, or poorly conserved orthologs were the most challenging for gene-finders.

  13. Molecular Analysis of the Cold Tolerant Antarctic Nematode, Panagrolaimus davidi

    PubMed Central

    Thorne, Michael A. S.; Kagoshima, Hiroshi; Clark, Melody S.; Marshall, Craig J.; Wharton, David A.

    2014-01-01

    Isolated and established in culture from the Antarctic in 1988, the nematode Panagrolaimus davidi has proven to be an ideal model for the study of adaptation to the cold. Not only is it the best-documented example of an organism surviving intracellular freezing but it is also able to undergo cryoprotective dehydration. As part of an ongoing effort to develop a molecular understanding of this remarkable organism, we have assembled both a transcriptome and a set of genomic scaffolds. We provide an overview of the transcriptome and a survey of genes involved in temperature stress. We also explore, in silico, the possibility that P. davidi will be susceptible to an environmental RNAi response, important for further functional studies. PMID:25098249

  14. Impact of Pinewood Nematode in North America: Present and Future

    PubMed Central

    Bergdahl, D. R.

    1988-01-01

    Bursaphelenchus xylophilus, pinewood nematode (PWN), is the most serious pest of pine forests in Japan, but in North America its role in pine wilt disease is still being studied. The PWN is known to infest many species of Pinus, with P. nigra, P. sylvestris, and P. thunbergii the most susceptible in the eastern United States. Because of its potential, several European countries (Finland, Norway, and Sweden) and Korea have established embargoes against the importation of coniferous wood from regions of the world known to be infested with the PWN. Although the PWN is not considered an economic pest in North American forests, the recent embargoes have established an impact on current forest management practices and an economic impact on North American export trade. PMID:19290210

  15. Radiation-induced gene expression in the nematode Caenorhabditis elegans

    NASA Technical Reports Server (NTRS)

    Nelson, Gregory A.; Jones, Tamako A.; Chesnut, Aaron; Smith, Anna L.

    2002-01-01

    We used the nematode C. elegans to characterize the genotoxic and cytotoxic effects of ionizing radiation in a simple animal model emphasizing the unique effects of charged particle radiation. Here we demonstrate by RT-PCR differential display and whole genome microarray hybridization experiments that gamma rays, accelerated protons and iron ions at the same physical dose lead to unique transcription profiles. 599 of 17871 genes analyzed (3.4%) showed differential expression 3 hrs after exposure to 3 Gy of radiation. 193 were up-regulated, 406 were down-regulated and 90% were affected only by a single species of radiation. A novel statistical clustering technique identified the regulatory relationships between the radiation-modulated genes and showed that genes affected by each radiation species were associated with unique regulatory clusters. This suggests that independent homeostatic mechanisms are activated in response to radiation exposure as a function of track structure or ionization density.

  16. Molecular relationships between closely related strains and species of nematodes

    NASA Technical Reports Server (NTRS)

    Butler, M. H.; Wall, S. M.; Luehrsen, K. R.; Fox, G. E.; Hecht, R. M.

    1981-01-01

    Electrophoretic comparisons have been made for 24 enzymes in the Bergerac and Bristol strains of Caenorhabditis elegans and the related species, Caenorhabditis briggsae. No variation was detected between the two strains of C. elegans. In contrast, the two species, C. elegans and C. briggsae exhibited electrophoretic differences in 22 of 24 enzymes. A consensus 5S rRNA sequence was determined for C. elegans and found to be identical to that from C. briggsae. By analogy with other species with relatively well established fossil records it can be inferred that the time of divergence between the two nematode species is probably in the tens of millions of years. The limited anatomical evolution during a time period in which proteins undergo extensive changes supports the hypothesis that anatomical evolution is not dependent on overall protein changes.

  17. Desiccation survival in an Antarctic nematode: molecular analysis using expressed sequenced tags

    PubMed Central

    Adhikari, Bishwo N; Wall, Diana H; Adams, Byron J

    2009-01-01

    Background Nematodes are the dominant soil animals in Antarctic Dry Valleys and are capable of surviving desiccation and freezing in an anhydrobiotic state. Genes induced by desiccation stress have been successfully enumerated in nematodes; however we have little knowledge of gene regulation by Antarctic nematodes which can survive multiple environmental stresses. To address this problem we investigated the genetic responses of a nematode species, Plectus murrayi, that is capable of tolerating Antarctic environmental extremes, in particular desiccation and freezing. In this study, we provide the first insight into the desiccation induced transcriptome of an Antarctic nematode through cDNA library construction and suppressive subtractive hybridization. Results We obtained 2,486 expressed sequence tags (ESTs) from 2,586 clones derived from the cDNA library of desiccated P. murrayi. The 2,486 ESTs formed 1,387 putative unique transcripts of which 523 (38%) had matches in the model-nematode Caenorhabditis elegans, 107 (7%) in nematodes other than C. elegans, 153 (11%) in non-nematode organisms and 605 (44%) had no significant match to any sequences in the current databases. The 1,387 unique transcripts were functionally classified by using Gene Ontology (GO) hierarchy and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The results indicate that the transcriptome contains a group of transcripts from diverse functional areas. The subtractive library of desiccated nematodes showed 80 transcripts differentially expressed during desiccation stress, of which 28% were metabolism related, 19% were involved in environmental information processing, 28% involved in genetic information processing and 21% were novel transcripts. Expression profiling of 14 selected genes by quantitative Real-time PCR showed 9 genes significantly up-regulated, 3 down-regulated and 2 continuously expressed in response to desiccation. Conclusion The establishment of a desiccation EST collection for Plectus murrayi, a useful model in assessing the structural, physiological, biochemical and genetic aspects of multiple stress tolerance, is an important step in understanding the genome level response of this nematode to desiccation stress. The type of transcript analysis performed in this study sets the foundation for more detailed functional and genome level analyses of the genes involved in desiccation tolerance in nematodes. PMID:19203352

  18. Intermediate filaments in muscle and epithelial cells of nematodes

    PubMed Central

    1986-01-01

    Current concepts of the developmentally controlled multigene family of intermediate filament (IF) proteins expect the origin of their complexity in evolutionary precursors preceding all vertebrate classes. Among invertebrates, however, firm ultrastructural as well as molecular documentation of IFs is restricted to some giant axons and to epithelia of a few molluscs and annelids. As Ascaris lumbricoides is easily dissected into clean tissues, IF expression in this large nematode was analyzed by electron microscopic and biochemical procedures and a monoclonal antibody reacting with all mammalian IF proteins. We document for the first time the presence of IFs in muscle cells of an invertebrate. They occur in three muscle types (irregular striated pharynx muscle, obliquely striated body muscle, uterus smooth muscle). IFs are also found in the epithelia studied (syncytial epidermis, intestine, ovary, testis). Immunoblots on muscles, pharynx, intestine, uterus, and epidermis identify a pair of polypeptides (with apparent molecular masses of 71 and 63 kD) as IF constituents. In vitro reconstitution of filaments was obtained with the proteins purified from body muscle. In the small nematode Caenorhabditis elegans IF proteins are so far found only in the massive desmosome-anchored tonofilament bundles which traverse a special epithelial cell type, the marginal cells of the pharynx. We speculate that IFs may occur in most but perhaps not all invertebrates and that they may not occur in all cells in large amounts. As electron micrographs of the epidermis of a planarian--a member of the Platyhelminthes--reveal IFs, the evolutionary origin of this cytoplasmic structure can be expected either among the lowest metazoa or already in some unicellular eukaryotes. PMID:3519620

  19. Divergent thermal specialisation of two South African entomopathogenic nematodes

    PubMed Central

    Malan, Antoinette P.; Terblanche, John S.

    2015-01-01

    Thermal physiology of entomopathogenic nematodes (EPN) is a critical aspect of field performance and fitness. Thermal limits for survival and activity, and the ability of these limits to adjust (i.e., show phenotypic flexibility) depending on recent thermal history, are generally poorly established, especially for non-model nematode species. Here we report the acute thermal limits for survival, and the thermal acclimation-related plasticity thereof for two key endemic South African EPN species, Steinernema yirgalemense and Heterorhabditis zealandica. Results including LT50 indicate S. yirgalemense (LT50 = 40.8 ± 0.3 °C) has greater high temperature tolerance than H. zealandica (LT50 = 36.7 ± 0.2 °C), but S. yirgalemense (LT50 = ?2.4 ± 0 °C) has poorer low temperature tolerance in comparison to H. zealandica (LT50 = ?9.7 ± 0.3 °C), suggesting these two EPN species occupy divergent thermal niches to one another. Acclimation had both negative and positive effects on temperature stress survival of both species, although the overall variation meant that many of these effects were non-significant. There was no indication of a consistent loss of plasticity with improved basal thermal tolerance for either species at upper lethal temperatures. At lower temperatures measured for H. zealandica, the 5 °C acclimation lowered survival until below ?12.5 °C, where after it increased survival. Such results indicate that the thermal niche breadth of EPN species can differ significantly depending on recent thermal conditions, and should be characterized across a broad range of species to understand the evolution of thermal limits to performance and survival in this group. PMID:26157609

  20. Interleukin-9 Enhances Resistance to the Intestinal Nematode Trichuris muris

    PubMed Central

    Faulkner, Helen; Renauld, J.-C.; Van Snick, J.; Grencis, R. K.

    1998-01-01

    Upon infection with the cecum-dwelling nematode Trichuris muris, the majority of inbred strains of mice launch a Th2-type immune response and in doing so expel the parasite before patency. In contrast, there are a few mouse strains which develop a nonprotective Th1-type response resulting in a chronic infection and the presence of adult worms. Of the Th2 cytokines known to be associated with the resistant phenotype (interleukin-4 [IL-4], IL-5, IL-9, and IL-13), comparatively little is known about the contribution that IL-9 makes towards the protective immune response. In this study we demonstrate that IL-9 is expressed early during the Th2-type response and that its elevation in vivo results in the enhancement of intestinal mastocytosis and the production of both the immunoglobulin E (IgE) and IgG1 isotypes. In addition, elevated IL-9 levels in vivo facilitated the loss of T. muris from the intestine. That IL-9 is important in promoting worm expulsion was also seen following infection of IL-9-transgenic mice, which constitutively overexpress the cytokine. These animals displayed an extremely rapid, but immune mediated, expulsion of the parasite. Also evident in these animals was a pronounced intestinal mastocytosis, which was previously shown by us to be responsible for the expulsion of the related nematode Trichinella spiralis from these animals. Taken together with observations of IL-9 production following infection with other helminths, the results imply that IL-9 contributes to the general mast cell and IgE response characteristic of these infections and, more specifically, enhances resistance to T. muris. PMID:9673269

  1. Functional Analysis of Pathogenicity Proteins of the Potato Cyst Nematode Globodera rostochiensis Using RNAi

    Microsoft Academic Search

    Qing Chen; S. Rehman; G. Smant; John T. Jones

    2005-01-01

    RNA interference (RNAi) has been used widely as a tool for examining gene function and a method that allows its use with plant-parasitic nematodes recently has been described. Here, we use a modified method to analyze the function of secreted ß-1,4, endoglucanases of the potato cyst nematode Globodera rostochiensis, the first in vivo functional analysis of a pathogenicity protein of

  2. Differences in efficacy of monepantel, derquantel and abamectin against multi-resistant nematodes of sheep

    Microsoft Academic Search

    Ronald Kaminsky; Beatrice Bapst; Philip A. Stein; Guenther A. Strehlau; Brooke A. Allan; Barry C. Hosking; Peter F. Rolfe; Heinz Sager

    2011-01-01

    Drug resistance has become a global phenomenon in gastrointestinal nematodes of sheep, particularly resistance to macrocyclic\\u000a lactones. New anthelmintics are urgently needed for both the control of infections with multi-resistant nematodes in areas\\u000a where classical anthelmintics are no longer effective, and the prevention of the spread of resistance in areas where the problem\\u000a is not as severe. Recently, two new

  3. Inheritance of a Broad-Based Form of Root-Knot Nematode Resistance in Cowpea

    Microsoft Academic Search

    A. S. Khehra; B. S. Dhillon

    of cowpea cultivars and accessions and an examination of breeding pedigrees suggested that the available resis- Root-knot nematodes (Meloidogyne spp.) are serious pests of cow- tance to root-knot nematodes is based on a single locus pea (Vigna unguiculata (L.) Walp.) and many other crops worldwide. Host plant resistance is the primary means for managing root-knot with allelic differences (Fery, 1985;

  4. The assessment of partial resistance of potato clones to cyst nematodes at six test centres

    Microsoft Academic Search

    M. S. Phillips; D. L. Trudgill; K. Evans; C. N. D. Lacey; M. Mackenzie; S. J. Turner

    1987-01-01

    Eleven potato cultivars or clones representing a range of resistances to potato cyst nematodes derived fromSolanum vernei orSolanum tuberosum ssp.andigena CPC 2802 were assessed in eight pot tests and one field trial. Six involvedGlobodera pallida Pa2\\/3, oneG. pallida Pa1, and twoG. rostochiensis Ro1. The nine tests were at six different centres each using their own nematode populations and standard techniques.

  5. Pelecitus helicinus Railliet & Henry, 1910 (Filarioidea, Dirofilariinae) and other nematode parasites of Brazilian birds.

    PubMed

    Oniki, Yoshika; Kinsella, J M; Willis, Edwin O

    2002-06-01

    We report Pelecitus helicinus Railliet & Henry, 1910 from 13 species of birds of 2 orders and 7 families, collected from the states of São Paulo and Mato Grosso, Brazil. All 13 constitute new host records for this nematode. In addition, we report the first record of Aprocta golvani Diaz-Ungria, 1963 from Brazil and Monasa nigrifrons (Bucconidae), as well as a number of other nematode records from Neotropical birds. PMID:12118298

  6. Regional patterns among soil nematode assemblages in Australasian pastures and effects of management practices

    Microsoft Academic Search

    G. W. Yeates; G. R. Stirling

    2008-01-01

    Abundance, composition and diversity of nematode assemblages at 58 sites from five Australasian regions (New Zealand, South\\u000a Australia, coastal southern Australia, New South Wales and Queensland) are analysed with particular reference to rainfall,\\u000a pasture type and proportions of plant-, bacterial- and fungal-feeders. Nematode abundance was generally related to plant production\\u000a or surrogates such as soil carbon concentration. Diversity was lowest

  7. Anisakid Nematode (Ascaridoidea) Life Cycles and Distribution: Increasing Zoonotic Potential in the Time of Climate Change?

    Microsoft Academic Search

    Sven Klimpel; Harry W. Palm

    \\u000a Parasitic nematodes are known as important pathogens that cause problems for human and animal health. Some of them naturally\\u000a inhabit the marine environment, where they are widespread and can be found in a variety of different hosts. Food-borne zoonoses\\u000a via aquatic animals are most often linked to anisakid nematodes of the genera Anisakis Dujardin, 1845, Contracaecum Railliet and Henry, 1912,

  8. Root-Knot Nematode Resistant Cowpea Cover Crops in Tomato Production Systems

    Microsoft Academic Search

    P. A. Roberts; W. C. Matthews; J. D. Ehlers

    2005-01-01

    growers who have few inexpensive sources of this nu- trient. Root-knot nematodes,Meloidogynespp., are serious pests of many Root-knot nematodes are major pests of agronomic crops worldwide. Recent limitations on the use of nematicides have enhanced the need to develop alternative management strategies, in- and vegetable crops worldwide and cause root galling, cluding host plant resistance. This study was conducted to

  9. Management Of Virus-Transmitting Nematodes With Special Emphasis On South-East Euroup

    Microsoft Academic Search

    Tatyana Bilevai; Boryana Choleva; Sue Hockland; Aurelio Ciancio

    Available strategies for the management of nematode vectors of plant viruses are reviewed, focusing on the nematode vector\\u000a species, their associated viruses, as well as their geographic distribution and spread. Diagnostic procedures including morphological\\u000a identification of virus vectors, plant tests and transmission assays as well as the application of molecular detection tools\\u000a are reviewed, in the light of preventive and

  10. Spatial Distribution of Soil Nematode Communities in Stable and Active Sand Dunes of Horqin Sandy Land

    Microsoft Academic Search

    Xiaoke Zhang; Xiwen Dong; Wenju Liang

    2010-01-01

    To explore the ecological significance of artificial plantation and the restoration process in sand dune ecosystems, the spatial distribution of soil nematode communities in stable and active sand dunes were investigated in northeastern Inner Mongolia, China. Soil nematode community structure and composition at five soil depths (0–5 cm, 5–10 cm, 10–20 cm, 20–40 cm, and 40–60 cm) and three slope positions (windward slope, top slope,

  11. Comparative serial analysis of gene expression of transcript profiles of tomato roots infected with cyst nematode

    Microsoft Academic Search

    Taketo Uehara; Shunpei Sugiyama; Chikara Masuta

    2007-01-01

    We analyzed global transcripts for tomato roots infected with the cyst nematode Globodera rostochiensis using serial analysis of gene expression (SAGE). SAGE libraries were made from nematode-infected roots and uninfected roots\\u000a at 14 days after inoculation, and the clones including SAGE tags were sequenced. Genes were identified by matching the SAGE\\u000a tags to tomato expressed sequence tags and cDNA databases.

  12. The nematode C. elegans - A model animal system for the detection of genetic and developmental lesions

    NASA Technical Reports Server (NTRS)

    Nelson, Gregory A.; Marshall, Tamara M.; Schubert, Wayne W.

    1989-01-01

    The effects of ionizing and nonionizing radiation effects on cell reproduction, differentiation, and mutation in vivo are studied using the nematode C. elegans. The relationships between fluence/dose and response and quality factor and linear energy transfer are analyzed. The data reveal that there is a complex repair pathway in the nematode and that mutants can be used to direct the sensitivity of the system to specific mutagens/radiation types.

  13. Combined effects of bacterial-feeding nematodes and prometryne on the soil microbial activity

    Microsoft Academic Search

    Jihai Zhou; Xuechao Li; Ying Jiang; Yue Wu; Jiandong Chen; Feng Hu; Huixin Li

    2011-01-01

    Microcosm experiments were carried out to study the effects of bacterial-feeding nematodes and indigenous microbes and their interactions on the degradation of prometryne and soil microbial activity in contaminated soil. The results showed that soil indigenous microbes could degrade prometryne up to 59.6–67.9%; bacterial-feeding nematodes accelerated the degradation of prometryne in contaminated soil, and prometryne degradation was raised by 8.36–10.69%.

  14. Host-delivered RNAi: an effective strategy to silence genes in plant parasitic nematodes

    Microsoft Academic Search

    David J. Fairbairn; Antonino S. Cavallaro; Margaret Bernard; Janani Mahalinga-Iyer; Michael W. Graham; José R. Botella

    2007-01-01

    Root-knot nematodes (Meloidogyne spp.) are obligate, sedentary endoparasites that infect many plant species causing large economic losses worldwide. Available\\u000a nematicides are being banned due to their toxicity or ozone-depleting properties and alternative control strategies are urgently\\u000a required. We have produced transgenic tobacco (Nicotiana tabacum) plants expressing different dsRNA hairpin structures targeting a root-knot nematode (Meloidogyne javanica) putative transcription factor, MjTis11.

  15. Host-derived suppression of nematode reproductive and fitness genes decreases fecundity of Heterodera glycines Ichinohe

    Microsoft Academic Search

    Jiarui Li; Timothy C. Todd; Tom R. Oakley; Junghoon Lee; Harold N. Trick

    2010-01-01

    To control Heterodera glycines Ichinohe (soybean cyst nematode) in Glycine max (L.) Merr. (soybean), we evaluated the use of producing transgenic soybean seedlings expressing small interfering RNAs (siRNAs)\\u000a against specific H. glycines genes. Gene fragments of three genes related to nematode reproduction or fitness (Cpn-1, Y25 and Prp-17) were PCR-amplified using specific primers and independently cloned into the pANDA35HK RNAi

  16. C. elegans as a Resource for Studies on Plant Parasitic Nematodes

    Microsoft Academic Search

    Laura M. Jones; Carla De Giorgi; Peter E. Urwin

    \\u000a \\u000a C. elegans provides a suitable model to study basic and conserved nematode biology. The short life-cycle, adult size, easy maintenance\\u000a in large numbers and the tractability of C. elegans facilitate its use in translational biology. The C. elegans genome project has greatly assisted the mapping, sequencing and annotation of parasitic nematode genomes. Furthermore, the\\u000a development of RNAi in C. elegans

  17. Soybean cyst nematode effects on soybean aphid preference and performance in the laboratory.

    PubMed

    Hong, S C; Donaldson, J; Gratton, C

    2010-10-01

    Herbivores on plants frequently interact via shared resources. Studies that have examined performance of herbivores in the presence of other herbivores, however, have often focused on above-ground feeding guilds and relatively less research has examined interactions between below- and above-ground consumers. We examine how soybean aphid, Aphis glycines (Matsumura) an above-ground phloem-feeding herbivore, interacts with a below-ground plant parasite, soybean cyst nematode, Heterodera glycines (Ichinohe) through their shared host plant, soybean (Glycine max L). Laboratory experiments evaluated the preference of alate (flight-capable) soybean aphids toward plants either infected with soybean cyst nematode or uninfected controls in a simple choice arena. Alate soybean aphids preferred uninfected soybean over soybean cyst nematode-infected plants: 48 h after the releases of alate aphids in the center of the arena, 67% more aphids were found on control soybean compared with nematode infected plants. No-choice feeding assays were also conducted using clip cages and apterous (flight-incapable) aphids to investigate effect of soybean cyst nematode infection of soybean on aphid performance. These studies had mixed results: in one set of experiments overall aphid population growth at 7 d was not statistically different between control and soybean cyst nematode-infected plants. A different experiment using a life-table analysis found that apterous aphids feeding on soybean cyst nematode-infected plants had significantly greater finite rate of increase (?), intrinsic rate of increase (r(m)), and net reproductive rate (R(o)) compared with aphids reared on uninfected (control) soybean plants. We conclude that the below-ground herbivore, soybean cyst nematode, primarily influences soybean aphid behavior rather than performance. PMID:22546453

  18. Dynamics in the tomato root transcriptome on infection with the potato cyst nematode Globodera rostochiensis

    Microsoft Academic Search

    MAGDALENA SWIECICKA; MARCIN FILIPECKI; DIEUWERTJE LONT; JOKE VAN VLIET; LING QIN; ASKA GOVERSE; JAAP BAKKER; JOHANNES HELDER

    2009-01-01

    Plant parasitic nematodes infect roots and trigger the formation of specialized feeding sites by substantial reprogramming of the developmental process of root cells. In this article, we describe the dynamic changes in the tomato root transcriptome during early interactions with the potato cyst nematode Globodera rostochiensis. Using amplified fragment length polymorphism-based mRNA fingerprinting (cDNA-AFLP), we monitored 17 600 transcript-derived fragments

  19. Spread of the pinewood nematode vectored by the Japanese pine sawyer: modeling and analytical approaches

    Microsoft Academic Search

    Katsumi Togashi; Nanako Shigesada

    2006-01-01

    The pinewood nematode, Bursaphelenchus xylophilus, is the causative agent of pine wilt of Pinus thunbergii and P. densiflora in Japan. The nematode is vectored by cerambycid beetles of the genus Monochamus. It is inferred to have been introduced from North America early in the 1900s and then to have distributed in China, Korea, and Taiwan. Intensive and\\/or long-term studies of

  20. Enhanced resistance to soybean cyst nematode Heterodera glycines in transgenic soybean by silencing putative CLE receptors.

    PubMed

    Guo, Xiaoli; Chronis, Demosthenis; De La Torre, Carola M; Smeda, John; Wang, Xiaohong; Mitchum, Melissa G

    2015-08-01

    CLE peptides are small extracellular proteins important in regulating plant meristematic activity through the CLE-receptor kinase-WOX signalling module. Stem cell pools in the SAM (shoot apical meristem), RAM (root apical meristem) and vascular cambium are controlled by CLE signalling pathways. Interestingly, plant-parasitic cyst nematodes secrete CLE-like effector proteins, which act as ligand mimics of plant CLE peptides and are required for successful parasitism. Recently, we demonstrated that Arabidopsis CLE receptors CLAVATA1 (CLV1), the CLAVATA2 (CLV2)/CORYNE (CRN) heterodimer receptor complex and RECEPTOR-LIKE PROTEIN KINASE 2 (RPK2), which transmit the CLV3 signal in the SAM, are required for perception of beet cyst nematode Heterodera schachtii CLEs. Reduction in nematode infection was observed in clv1, clv2, crn, rpk2 and combined double and triple mutants. In an effort to develop nematode resistance in an agriculturally important crop, orthologues of Arabidopsis receptors including CLV1, CLV2, CRN and RPK2 were identified from soybean, a host for the soybean cyst nematode Heterodera glycines. For each of the receptors, there are at least two paralogues in the soybean genome. Localization studies showed that most receptors are expressed in the root, but vary in their level of expression and spatial expression patterns. Expression in nematode-induced feeding cells was also confirmed. In vitro direct binding of the soybean receptors with the HgCLE peptide was analysed. Knock-down of the receptors in soybean hairy roots showed enhanced resistance to SCN. Our findings suggest that targeted disruption of nematode CLE signalling may be a potential means to engineer nematode resistance in crop plants. PMID:25581705

  1. Horizontally transferred genes in plant-parasitic nematodes: a high-throughput genomic approach

    Microsoft Academic Search

    Elizabeth H Scholl; Jeffrey L Thorne; James P McCarter; David Mck Bird

    2003-01-01

    BACKGROUND: Published accounts of horizontally acquired genes in plant-parasitic nematodes have not been the result of a specific search for gene transfer per se, but rather have emerged from characterization of individual genes. We present a method for a high-throughput genome screen for horizontally acquired genes, illustrated using expressed sequence tag (EST) data from three species of root-knot nematode, Meloidogyne

  2. Brassicaceous and rye cover crops altered free-living soil nematode community composition

    Microsoft Academic Search

    Lisa Stocking Gruver; Ray R. Weil; Inga A. Zasada; Sandra Sardanelli; Bahram Momen

    2010-01-01

    Nematode community analysis was utilized to evaluate the biofumigant or allelopathic effects of brassicaceous and rye winter cover crops on non-target nematodes in three experiments (two sites) in Maryland. The cover crop treatments included mustard blend (Sinapis alba and Brassica juncea) ‘Caliente’, rapeseed (B. napus) ‘Essex’\\/’Humus’, forage radish (Raphanus sativus) ‘Dichon’, oilseed radish (R. sativus) ‘Adagio’\\/’Colonel’, rye (Secale cereale) ‘Wheeler’

  3. Relation between nematode communities and trophic state in southern Swedish lakes

    Microsoft Academic Search

    Kai Ristau; Walter Traunspurger

    2011-01-01

    The aim of this study was to examine whether littoral nematode community patterns are shaped by lake trophic state. It was\\u000a hypothesized that trophic level is associated negatively with the proportion of omnivores and positively with the percentages\\u000a of bacterial feeders, but not at all with the diversity, abundance, and biomass of freshwater nematodes. Sediment samples\\u000a were taken at littoral

  4. Serine Protease(s) Secreted by the Nematode Trichuris muris Degrade the Mucus Barrier

    PubMed Central

    Hasnain, Sumaira Z.; McGuckin, Michael A.; Grencis, Richard K.; Thornton, David J.

    2012-01-01

    The polymeric mucin component of the intestinal mucus barrier changes during nematode infection to provide not only physical protection but also to directly affect pathogenic nematodes and aid expulsion. Despite this, the direct interaction of the nematodes with the mucins and the mucus barrier has not previously been addressed. We used the well-established Trichuris muris nematode model to investigate the effect on mucins of the complex mixture of immunogenic proteins secreted by the nematode called excretory/secretory products (ESPs). Different regimes of T. muris infection were used to simulate chronic (low dose) or acute (high dose) infection. Mucus/mucins isolated from mice and from the human intestinal cell line, LS174T, were treated with ESPs. We demonstrate that serine protease(s) secreted by the nematode have the ability to change the properties of the mucus barrier, making it more porous by degrading the mucin component of the mucus gel. Specifically, the serine protease(s) acted on the N-terminal polymerising domain of the major intestinal mucin Muc2, resulting in depolymerisation of Muc2 polymers. Importantly, the respiratory/gastric mucin Muc5ac, which is induced in the intestine and is critical for worm expulsion, was protected from the depolymerising effect exerted by ESPs. Furthermore, serine protease inhibitors (Serpins) which may protect the mucins, in particular Muc2, from depolymerisation, were highly expressed in mice resistant to chronic infection. Thus, we demonstrate that nematodes secrete serine protease(s) to degrade mucins within the mucus barrier, which may modify the niche of the parasite to prevent clearance from the host or facilitate efficient mating and egg laying from the posterior end of the parasite that is in intimate contact with the mucus barrier. However, during a TH2-mediated worm expulsion response, serpins, Muc5ac and increased levels of Muc2 protect the barrier from degradation by the nematode secreted protease(s). PMID:23071854

  5. Catalogue of Types Deposited in the Canadian National Collection of Nematodes

    PubMed Central

    Anderson, R. V.; Ebsary, B. A.

    1985-01-01

    Primary and secondary types housed in the Canadian National Collection of Nematodes are given for 396 species of plant-parasitic, marine, freshwater, terrestrial, and entomophagous nematodes. Species are listed in alphabetical order and include author(s), date, publication source, type category, numbers and sex, and collection accession number. Current nomenclatorial changes in status of a binomial are not given, but authority data are added for type designations made to the original type series. PMID:19294084

  6. Dynamics in the tomato root transcriptome on infection with the potato cyst nematode Globodera rostochiensis.

    PubMed

    Swiecicka, Magdalena; Filipecki, Marcin; Lont, Dieuwertje; Van Vliet, Joke; Qin, Ling; Goverse, Aska; Bakker, Jaap; Helder, Johannes

    2009-07-01

    Plant parasitic nematodes infect roots and trigger the formation of specialized feeding sites by substantial reprogramming of the developmental process of root cells. In this article, we describe the dynamic changes in the tomato root transcriptome during early interactions with the potato cyst nematode Globodera rostochiensis. Using amplified fragment length polymorphism-based mRNA fingerprinting (cDNA-AFLP), we monitored 17 600 transcript-derived fragments (TDFs) in infected and uninfected tomato roots, 1-14 days after inoculation with nematode larvae. Six hundred and twenty-four TDFs (3.5%) showed significant differential expression on nematode infection. We employed GenEST, a computer program which links gene expression profiles generated by cDNA-AFLP and databases of cDNA sequences, to identify 135 tomato sequences. These sequences were grouped into eight functional categories based on the presence of genes involved in hormone regulation, plant pathogen defence response, cell cycle and cytoskeleton regulation, cell wall modification, cellular signalling, transcriptional regulation, primary metabolism and allocation. The presence of unclassified genes was also taken into consideration. This article describes the responsiveness of numerous tomato genes hitherto uncharacterized during infection with endoparasitic cyst nematodes. The analysis of transcriptome profiles allowed the sequential order of expression to be dissected for many groups of genes and the genes to be connected with the biological processes involved in compatible interactions between the plant and nematode. PMID:19523102

  7. Transgenic potatoes for potato cyst nematode control can replace pesticide use without impact on soil quality.

    PubMed

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

    2012-01-01

    Current and future global crop yields depend upon soil quality to which soil organisms make an important contribution. The European Union seeks to protect European soils and their biodiversity for instance by amending its Directive on pesticide usage. This poses a challenge for control of Globodera pallida (a potato cyst nematode) for which both natural resistance and rotational control are inadequate. One approach of high potential is transgenically based resistance. This work demonstrates the potential in the field of a new transgenic trait for control of G. pallida that suppresses root invasion. It also investigates its impact and that of a second transgenic trait on the non-target soil nematode community. We establish that a peptide that disrupts chemoreception of nematodes without a lethal effect provides resistance to G. pallida in both a containment and a field trial when precisely targeted under control of a root tip-specific promoter. In addition we combine DNA barcoding and quantitative PCR to recognise nematode genera from soil samples without microscope-based observation and use the method for nematode faunal analysis. This approach establishes that the peptide and a cysteine proteinase inhibitor that offer distinct bases for transgenic plant resistance to G. pallida do so without impact on the non-target nematode soil community. PMID:22359559

  8. Consequences of Melaleuca quinquenervia Invasion on Soil Nematodes in the Florida Everglades

    PubMed Central

    Porazinska, Dorota L.; Pratt, Paul D.; Glblin-Davis, Robin M.

    2007-01-01

    The tree Melaleuca quinquenervia invades all types of habitats of South Florida leading to up to 80% loss of aboveground diversity. To examine impacts on the belowground ecosystem, we investigated the composition and diversity of nematodes from soils dominated by the invasive tree and compared them with soils supporting native plant communities at six locations across the Florida Everglades over three years. Despite the significant differences in soil type, hydrology, and native plant composition of the sites, there were consistent differences in nematode communities between soil environments under the native and invaded plant communities. The total abundance and diversity of nematodes in soils dominated by M. quinquenervia was 60% and 80% of adjacent soils under native plants. Fungal-feeding and plant-parasitic nematodes were twice as abundant under native plants as under M. quinquenervia. Nematode communities under M. quinquenervia were bacterivore-dominated, while under native vegetation plant-parasite dominated. The overall diversity of nematodes was 20% lower under the exotic than under native plants, with plant parasites being 36% and fungivores being 30% less diverse. Soil moisture, % of Ca, Mg, and clay particles and total soil C and N were greater in M. quinquenervia soils, but plant-available concentrations of P, K, Ca, and Mg as well as CEC were reduced. Overall, data suggests that the invasion process may modify soil biotic and abiotic conditions that in turn promote the advancement of the exotic M. quinquenervia and displacement of the native plants. PMID:19259503

  9. An Aphelenchoides sp. nematode Parasitic of Polianthes tuberosa in the Mekong Delta

    PubMed Central

    Thi Thu Cuc, Nguyen; Pilon, Marc

    2007-01-01

    Polianthes tuberosa is a commercially valuable flower crop in the Mekong Delta of Vietnam that is propagated by the harvesting and planting of bulbs. The cultivation of P. tuberosa is complicated by an endemic nematode infection that damages a high proportion of the plants. Based on morphological criteria and ribosomal RNA gene sequencing, we have determined that the infection is caused by an Aphelenchoides sp. nematode and is most likely Aphelenchoides besseyi. By scoring various parts of harvested plants with flowers for the presence of viable nematodes over a period of six months, we determined that the nematode is an ectoparasite that can survive the intercrop periods, especially in the bulbs that are used to plant new crops. A comparison of farming practices in the Mekong Delta failed to identify useful control methods, but rather indicated that fields that have cultivated P. tuberosa for the longest periods suffer the worst damage from the nematode infection. Finally, we demonstrated that the nematode is capable of infecting 30 rice cultivars but does not cause the white tip disease usually associated with A. besseyi infection. PMID:19259495

  10. Plant-parasitic Nematodes in the Waimanalo, Hawaii Irrigation System from Watershed to Farm

    PubMed Central

    Zhang, Fengru; Schmitt, D. P.

    2001-01-01

    Nematode occurrence at specific locations throughout a water catchment-irrigation system was determined. Soil samples were collected from five water source locations on the slopes of Olomana Mountain and Maunawili Valley and from about 40 plant species on 18 farms (56 ha of 480 ha irrigated by the reservoir). Water was sampled from the catchment reservoir at 0.3 m, 9 m, and 18 m (bottom). A farm irrigated with potable water was sampled and compared to areas of the same farm irrigated from the reservoir. Nematodes present in soil from the mountain and farms were root-knot (Meloidogyne spp.), lesion (Pratylenchus spp.), reniform (Rotylenchulus reniformis), stunt (Tylenchorhynchus sp.), ring (Criconema spp.), dagger (Xiphinema sp.), spiral (Helicotylenchus sp.), Tylenchus sp., Aphelenchus sp., and pin (Paratylenchus sp.) nematodes. The economically important genera Rotylenchulus, Meloidogyne, and Pratylenchus occurred in very low numbers (10, 41, and 10/250 cm³ soil, respectively) and in low frequency (10%, 25%, and 8% of the samples, respectively) in the mountain samples compared with high numbers (170-895/250 cm³ soil) from farms. Frequency of occurrence over all farms was near 40% for Meloidogyne and 80% for Rotylenchulus. No nematodes were detected in water from the reservoir. One sample from the outlets contained two specimens of plant-parasitic nematodes. The population densities of nematodes were not different between the soil samples collected from crops irrigated by potable or reservoir water. PMID:19265890

  11. Comparative serial analysis of gene expression of transcript profiles of tomato roots infected with cyst nematode.

    PubMed

    Uehara, Taketo; Sugiyama, Shunpei; Masuta, Chikara

    2007-01-01

    We analyzed global transcripts for tomato roots infected with the cyst nematode Globodera rostochiensis using serial analysis of gene expression (SAGE). SAGE libraries were made from nematode-infected roots and uninfected roots at 14 days after inoculation, and the clones including SAGE tags were sequenced. Genes were identified by matching the SAGE tags to tomato expressed sequence tags and cDNA databases. We then compiled a list of numerous genes according to the mRNA levels that were altered after cyst nematode infection. Our SAGE results showed significant changes in expression of many unreported genes involved in nematode infection. Of these, for discussion we selected five SAGE tags of RSI-1, BURP domain-containing protein, hexose transporter, P-rich protein, and PHAP2A that were activated by cyst nematode infection. Over 20% of the tags that were upregulated in the infected root have unknown functions (non-annotated), suggesting that we can obtain information on previously unreported and uncharacterized genes by SAGE. We can also obtain information on previously reported genes involved in nematode infection (e.g., multicystatin, peroxidase, catalase, pectin esterase, and S-adenosylmethionine transferase). To evaluate the validity of our SAGE results, seven genes were further analyzed by semiquantitative reverse transcriptase-polymerase chain reaction and Northern blot hybridization; the results agreed well with the SAGE data. PMID:16983456

  12. Temporary Changes in Populations of Soil Organisms after Field Application of Entomopathogenic Nematodes

    PubMed Central

    Chevalier, R.; Webster, J.M.

    2006-01-01

    To assess the effect of an inundative release of entomopathogenic nematodes on soil organisms, population densities of soil-dwelling organisms were monitored before and after an application of an aqueous suspension of Heterorhabditis megidis to field plots in mown grassland (Exp. I) at a level of 0.38 million/m2 and to plots (Exp. II) situated in a forested area, a grass sports field and an orchard at a level of 1.5 million/m2. At the forested site, heat-killed H. megidis (1.5 million/m2) also were applied to two plots to compare the impact on soil organisms of a large introduction of living and dead nematodes. Post-treatment, temporary changes in natural population densities of several nematode genera and other organisms were detected in H. megidis-treated plots in both experiments. Temporary changes in the nematode trophic structure occurred in the percentages of nematode omnivores, herbivores and predators in both experiments. Evidence from all sites suggests that the changes were temporary and that the presence of decaying H. megidis following treatment contributed to nutrient enrichment of the soil and to direct and indirect effects on the nematode community. PMID:19259465

  13. Comparative Genomics and Transcriptomics Analyses Reveal Divergent Lifestyle Features of Nematode Endoparasitic Fungus Hirsutella minnesotensis

    PubMed Central

    Lai, Yiling; Liu, Keke; Zhang, Xinyu; Zhang, Xiaoling; Li, Kuan; Wang, Niuniu; Shu, Chi; Wu, Yunpeng; Wang, Chengshu; Bushley, Kathryn E.; Xiang, Meichun; Liu, Xingzhong

    2014-01-01

    Hirsutella minnesotensis [Ophiocordycipitaceae (Hypocreales, Ascomycota)] is a dominant endoparasitic fungus by using conidia that adhere to and penetrate the secondary stage juveniles of soybean cyst nematode. Its genome was de novo sequenced and compared with five entomopathogenic fungi in the Hypocreales and three nematode-trapping fungi in the Orbiliales (Ascomycota). The genome of H. minnesotensis is 51.4 Mb and encodes 12,702 genes enriched with transposable elements up to 32%. Phylogenomic analysis revealed that H. minnesotensis was diverged from entomopathogenic fungi in Hypocreales. Genome of H. minnesotensis is similar to those of entomopathogenic fungi to have fewer genes encoding lectins for adhesion and glycoside hydrolases for cellulose degradation, but is different from those of nematode-trapping fungi to possess more genes for protein degradation, signal transduction, and secondary metabolism. Those results indicate that H. minnesotensis has evolved different mechanism for nematode endoparasitism compared with nematode-trapping fungi. Transcriptomics analyses for the time-scale parasitism revealed the upregulations of lectins, secreted proteases and the genes for biosynthesis of secondary metabolites that could be putatively involved in host surface adhesion, cuticle degradation, and host manipulation. Genome and transcriptome analyses provided comprehensive understanding of the evolution and lifestyle of nematode endoparasitism. PMID:25359922

  14. Small Intestinal Nematode Infection of Mice Is Associated with Increased Enterobacterial Loads alongside the Intestinal Tract

    PubMed Central

    Rausch, Sebastian; Held, Josephin; Fischer, André; Heimesaat, Markus M.; Kühl, Anja A.; Bereswill, Stefan; Hartmann, Susanne

    2013-01-01

    Parasitic nematodes are potent modulators of immune reactivity in mice and men. Intestinal nematodes live in close contact with commensal gut bacteria, provoke biased Th2 immune responses upon infection, and subsequently lead to changes in gut physiology. We hypothesized that murine nematode infection is associated with distinct changes of the intestinal bacterial microbiota composition. We here studied intestinal inflammatory and immune responses in mice following infection with the hookworm Heligmosomoidespolygyrusbakeri and applied cultural and molecular techniques to quantitatively assess intestinal microbiota changes in the ileum, cecum and colon. At day 14 post nematode infection, mice harbored significantly higher numbers of ?-Proteobacteria/Enterobacteriaceae and members of the Bacteroides/Prevotella group in their cecum as compared to uninfected controls. Abundance of Gram-positive species such as Lactobacilli, Clostridia as well as the total bacterial load was not affected by worm infection. The altered microbiota composition was independent of the IL-4/-13 – STAT6 signaling axis, as infected IL-4R?-/- mice showed a similar increase in enterobacterial loads. In conclusion, infection with an enteric nematode is accompanied by distinct intestinal microbiota changes towards higher abundance of gram-negative commensal species at the small intestinal site of infection (and inflammation), but also in the parasite-free large intestinal tract. Further studies should unravel the impact of nematode-induced microbiota changes in inflammatory bowel disease to allow for a better understanding of how theses parasites interfere with intestinal inflammation and bacterial communities in men. PMID:24040152

  15. Spread and Transmission of Bacterial Pathogens in Experimental Populations of the Nematode Caenorhabditis elegans

    PubMed Central

    Restif, Olivier

    2014-01-01

    Caenorhabditis elegans is frequently used as a model species for the study of bacterial virulence and innate immunity. In recent years, diverse mechanisms contributing to the nematode's immune response to bacterial infection have been discovered. Yet despite growing interest in the biochemical and molecular basis of nematode-bacterium associations, many questions remain about their ecology. Although recent studies have demonstrated that free-living nematodes could act as vectors of opportunistic pathogens in soil, the extent to which worms may contribute to the persistence and spread of these bacteria has not been quantified. We conducted a series of experiments to test whether colonization of and transmission between C. elegans nematodes could enable two opportunistic pathogens (Salmonella enterica and Pseudomonas aeruginosa) to spread on agar plates occupied by Escherichia coli. We monitored the transmission of S. enterica and P. aeruginosa from single infected nematodes to their progeny and measured bacterial loads both within worms and on the plates. In particular, we analyzed three factors affecting the dynamics of bacteria: (i) initial source of the bacteria, (ii) bacterial species, and (iii) feeding behavior of the host. Results demonstrate that worms increased the spread of bacteria through shedding and transmission. Furthermore, we found that despite P. aeruginosa's relatively high transmission rate among worms, its pathogenic effects reduced the overall number of worms colonized. This study opens new avenues to understand the role of nematodes in the epidemiology and evolution of pathogenic bacteria in the environment. PMID:24973073

  16. Bacteriophage migration via nematode vectors: host-parasite-consumer interactions in laboratory microcosms.

    PubMed

    Dennehy, John J; Friedenberg, Nicholas A; Yang, Yul W; Turner, Paul E

    2006-03-01

    Pathogens vectored by nematodes pose serious agricultural, economic, and health threats; however, little is known of the ecological and evolutionary aspects of pathogen transmission by nematodes. Here we describe a novel model system with two trophic levels, bacteriophages and nematodes, each of which competes for bacteria. We demonstrate for the first time that nematodes are capable of transmitting phages between spatially distinct patches of bacteria. This model system has considerable advantages, including the ease of maintenance and manipulation at the laboratory bench, the ability to observe many generations in short periods, and the capacity to freeze evolved strains for later comparison to their ancestors. More generally, experimental studies of complex multispecies interactions, host-pathogen coevolution, disease dynamics, and the evolution of virulence may benefit from this model system because current models (e.g., chickens, mosquitoes, and malaria parasites) are costly to maintain, are difficult to manipulate, and require considerable space. Our initial explorations centered on independently assessing the impacts of nematode, bacterium, and phage population densities on virus migration between host patches. Our results indicated that virus transmission increases with worm density and host bacterial abundance; however, transmission decreases with initial phage abundance, perhaps because viruses eliminate available hosts before migration can occur. We discuss the microbial growth dynamics that underlie these results, suggest mechanistic explanations for nematode transmission of phages, and propose intriguing possibilities for future research. PMID:16517645

  17. A Survey of Phytoparasitic Nematodes on Cultivated and Non-Cultivated Plants in Northwestern Egypt

    PubMed Central

    Ibrahim, I. K. A.; Handoo, Z. A.; El-Sherbiny, A. A.

    2000-01-01

    Surveys were conducted in Alexandria, El-Behera, and Matrouh Governorates in northwestern Egypt during the 1994-1998 cropping seasons to study the occurrence, population density, host associations, and distribution of phytoparasitic nematodes associated with 35 major crops, grasses, and weeds. A total of 220 soil and root samples containing mixed populations of 26 genera and 38 species of phytoparasitic nematodes was analyzed; three known genera and 13 known species are reported for the first time in northwestern Egypt. Root-knot nematodes with 34 occurrences were the most frequently encountered group of nematodes, followed by spiral, stunt, ring, lesion, lance, and dagger nematodes with 19, 18, 15, 9, 8, and 7 occurrences, respectively. New species records are Boleodorus pakistanensis, Criconemella sphaerocephala, Discocriconemella sphaerocephaloides, Hemicriconemoides cocophilus, Hemicycliophora thienmanni, Hoplolaimus clarissimus, Irantylenchus clavidorus, Merlinius nanus, Paratylenchus projectus, Tylenchorhynchus ebriensis, Tylenchus afghanicus, T. exiguus, Xiphinema basilgoodeyi, and X. ensiculiferum. Survey results showed new host plant records for most of the identified nematode species in Egypt. PMID:19270998

  18. Estimate of Yield Loss from the Citrus Nematode in Texas Grapefruit

    PubMed Central

    Timmer, L. W.; Davis, R. M.

    1982-01-01

    Chemical control of the citrus nematode, Tylenchulus semipenetrans Cobb, has consistently increased yield of grapefruit on sour orange rootstock in Texas. In this study, data from chemical control tests conducted from 1973 to 1980 were analyzed to determine the relationship between nematode counts and grapefruit yield and fruit size. The correlation between yield and nematode counts was negative (r = -0.47) and highly significant (P < 0.01). The data best fit the exponential decay curve: y = 160.3e-0.0000429 where y = yield in kg/tree and x = nematodes/100 cm³ of soil. The correlation between fruit size and nematode counts was not significant because yield and fruit size were inversely related. Yield loss in an average untreated orchard was estimated to be 12.4 tons/ha. Economic loss to citrus nematode in Texas grapefruit, assuming no treatment and an average on-tree price of $60/ton, was estimated to be $13.2 million annually. PMID:19295756

  19. Evidence of Hermaphroditism and Sex Ratio Distortion in the Fungal Feeding Nematode Bursaphelenchus okinawaensis

    PubMed Central

    Shinya, Ryoji; Hasegawa, Koichi; Chen, Anthony; Kanzaki, Natsumi; Sternberg, Paul W.

    2014-01-01

    Nematodes have many different reproductive strategies along with their divergent life histories; the ability of hermaphrodite to self- and cross-fertilize is useful for genetic manipulation. Here, we demonstrate the hermaphroditism of the fungal feeding nematode Bursaphelenchus okinawaensis, which was formerly described as a parthenogenetic nematode, and we show its other unique sexual characteristics. To determine that it is hermaphroditic, we performed the following experiments: observation of the pronuclear and chromosome behavior during oogenesis and early embryogenesis; observation of spermatogenesis during the fourth larval stage; investigation of sperm utilization; and investigation of phenotypic segregation after cross-mating using a chemically induced visible mutant. We then investigated the mating preferences and spermatid size difference between males and hermaphrodites. B. okinawaensis males successfully mated only with sperm-depleted old hermaphrodites, and the spermatid sizes of males were almost the same as those of hermaphrodites. Moreover, the sex ratio of cross-fertilized progeny was highly skewed toward hermaphrodites. B. okinawaensis is phylogenetically distant from established model nematodes such as C. elegans and is more closely related to some economically relevant parasitic nematodes. This newly discovered hermaphroditic nematode has great potential for evolutionary and parasitological research. PMID:25122669

  20. Effectiveness of native West African arbuscular mycorrhizal fungi in protecting vegetable crops against root-knot nematodes

    Microsoft Academic Search

    Antoine Affokpon; Danny L. Coyne; Louis Lawouin; Colette Tossou; Rufin Dossou Agbèdè; Jozef Coosemans

    2011-01-01

    Twenty strains of arbuscular mycorrhizal fungi (AMF), native to West Africa, and three commercial AMF, were evaluated for\\u000a their protective effect against root-knot nematodes, Meloidogyne spp., in pots and field experiments in Benin. In pots, these strains were assessed in sterilized soil following inoculation\\u000a of nematodes and in non-sterilized soil naturally infested with nematodes using tomato. The four strains showing

  1. Biological Control of Plant-Parasitic Nematodes: An Ecological Perspective, a Review of Progress and Opportunities for Further Research

    Microsoft Academic Search

    Graham R. Stirling

    \\u000a Plant-parasitic nematodes are important pests, causing billions of dollars damage to the world’s food and fibre crops. However,\\u000a from an ecological perspective, this group of nematodes is simply one component in a vast array of organisms that live in\\u000a soil. All these organisms interact with nematodes and with each other, and during that process, contribute to regulatory mechanisms\\u000a that maintain

  2. Plant-parasitic nematodes in Australian viticulture: key pests, current management practices and opportunities for future improvements

    Microsoft Academic Search

    G. E. Walker; G. R. Stirling

    2008-01-01

    This paper provides a brief overview of the Australian grape industry and discusses the distribution and economic importance\\u000a of its main nematode pests and outlines the management practices (hot water treatment of planting material, nematode-resistant\\u000a rootstocks and nematicides) that are currently used to minimise losses from nematodes. However, the main focus of the paper\\u000a is the research that will be

  3. The state of knowledge on deep-sea nematode taxonomy: how many valid species are known down there?

    Microsoft Academic Search

    Dmitry M. Miljutin; Gunnar Gad; Maria M. Miljutina; Vadim O. Mokievsky; Verônica Fonseca-Genevois; André M. Esteves

    2010-01-01

    All available information from literature sources dealing with deep-sea nematode species was analyzed, in order to obtain\\u000a an overview of the state of knowledge in deep-sea nematode taxonomy and answer the question of how many valid nematode species\\u000a are known from the deep sea so far. One hundred and twenty-seven taxonomic and ecological literature sources reported a total\\u000a of 638

  4. First report of a mermithid nematode infecting the invasive Megacopta cribraria (Hemiptera: Plataspidae) in the United States.

    PubMed

    Stubbins, F L; Agudelo, P; Reay-Jones, F P F; Greene, J K

    2015-05-01

    Megacopta cribraria (Hemiptera: Plataspidae) has become a pest of soybean, Glycine max (L.), in the United States. While several natural enemies of M. cribraria have been reported, our study is the first to report nematodes beneath the pleural membranes in the abdominal cavities of adults. Morphological and molecular analyses suggest this nematode belongs to the family Mermithidae. This first report of a nematode infection in M. cribraria adds to the current inventory of enemies attacking this insect. Our observations provide a basis for future research to examine the impact of nematodes on M. cribraria mortality and to investigate their capacity to reduce populations. PMID:25731127

  5. Optimization of a Host Diet for in vivo Production of Entomopathogenic Nematodes

    PubMed Central

    Shapiro-Ilan, David; Guadalupe Rojas, M.; Morales-Ramos, Juan A.; Louis Tedders, W.

    2012-01-01

    To facilitate improved in vivo culture of entomopathogenic nematodes, production of both insect hosts and nematodes should be optimized for maximum fitness, quality, and cost efficiency. In previous studies, we developed an improved diet for Tenebrio molitor, a host that is used for in vivo nematode production, and we demonstrated that single insect diet components (e.g., lipids and proteins) can have a positive or negative impact on entomopathogenic nematode fitness and quality. In this study, we tested components of our improved T. molitor diet (lipids, cholesterol, and a salt [MnSO4]) alone and in combination for effects on host susceptibility and reproductive capacity of Heterorhabditis indica and Steinernema carpocapsae. Our results indicated that moderate levels of lipids (10%) increased host susceptibility to S. carpocapsae but did not affect H. indica, whereas cholesterol and MnSO4 increased host susceptibility to H. indica but not S. carpocapsae. The combined T. molitor diet (improved for increased insect growth) increased host susceptibility to S. carpocapsae and had a neutral effect on H. indica; interactions among single diet ingredients were observed. No effects of insect host diet were detected on the reproductive capacity of either nematode species in T. molitor. Subsequently, progeny infective juveniles, derived from nematodes grown in T. molitor that were fed diets with varying nutritive components were tested for virulence to and reproduction capacity in the target pest Diaprepes abbreviatus. The progeny nematodes produced from differing T. molitor diet treatments did not differ in virulence except H. indica derived from a diet that lacked cholesterol or MnS04 (but contained lipids) did not cause significant D. abbreviatus suppression relative to the water control. We conclude that the improved insect host diet is compatible with production of H. indica and S. carpocapsae, and increases host susceptibility in S. carpocapsae. Furthermore, in a general sense, our results indicate host diets can be optimized for improved in vivo entomopathogenic nematode production efficiency. This is the first report of an insect diet that was optimized for both host and entomopathogenic nematode production. Additionally, our study indicates that host diet may impact broader aspects of entomopathogenic nematode ecology and pest control efficacy. PMID:23481558

  6. Transcriptome Analysis of Resistant and Susceptible Alfalfa Cultivars Infected With Root-Knot Nematode Meloidogyne incognita

    PubMed Central

    Postnikova, Olga A.; Hult, Maria; Shao, Jonathan; Skantar, Andrea; Nemchinov, Lev G.

    2015-01-01

    Nematodes are one of the major limiting factors in alfalfa production. Root-knot nematodes (RKN, Meloidogyne spp.) are widely distributed and economically important sedentary endoparasites of agricultural crops and they may inflict significant damage to alfalfa fields. As of today, no studies have been published on global gene expression profiling in alfalfa infected with RKN or any other plant parasitic nematode. Very little information is available about molecular mechanisms that contribute to pathogenesis and defense responses in alfalfa against these pests and specifically against RKN. In this work, we performed root transcriptome analysis of resistant (cv. Moapa 69) and susceptible (cv. Lahontan) alfalfa cultivars infected with RKN Meloidogyne incognita, widespread root-knot nematode species and a major pest worldwide. A total of 1,701,622,580 pair-end reads were generated on an Illumina Hi-Seq 2000 platform from the roots of both cultivars and assembled into 45,595 and 47,590 transcripts in cvs Moapa 69 and Lahontan, respectively. Bioinformatic analysis revealed a number of common and unique genes that were differentially expressed in susceptible and resistant lines as a result of nematode infection. Although the susceptible cultivar showed a more pronounced defense response to the infection, feeding sites were successfully established in its roots. Characteristically, basal gene expression levels under normal conditions differed between the two cultivars as well, which may confer advantage to one of the genotypes toward resistance to nematodes. Differentially expressed genes were subsequently assigned to known Gene Ontology categories to predict their functional roles and associated biological processes. Real-time PCR validated expression changes in genes arbitrarily selected for experimental confirmation. Candidate genes that contribute to protection against M. incognita in alfalfa were proposed and alfalfa-nematode interactions with respect to resistance are discussed. PMID:25710378

  7. Genomic mechanisms accounting for the adaptation to parasitism in nematode-trapping fungi.

    PubMed

    Meerupati, Tejashwari; Andersson, Karl-Magnus; Friman, Eva; Kumar, Dharmendra; Tunlid, Anders; Ahrén, Dag

    2013-11-01

    Orbiliomycetes is one of the earliest diverging branches of the filamentous ascomycetes. The class contains nematode-trapping fungi that form unique infection structures, called traps, to capture and kill free-living nematodes. The traps have evolved differently along several lineages and include adhesive traps (knobs, nets or branches) and constricting rings. We show, by genome sequencing of the knob-forming species Monacrosporium haptotylum and comparison with the net-forming species Arthrobotrys oligospora, that two genomic mechanisms are likely to have been important for the adaptation to parasitism in these fungi. Firstly, the expansion of protein domain families and the large number of species-specific genes indicated that gene duplication followed by functional diversification had a major role in the evolution of the nematode-trapping fungi. Gene expression indicated that many of these genes are important for pathogenicity. Secondly, gene expression of orthologs between the two fungi during infection indicated that differential regulation was an important mechanism for the evolution of parasitism in nematode-trapping fungi. Many of the highly expressed and highly upregulated M. haptotylum transcripts during the early stages of nematode infection were species-specific and encoded small secreted proteins (SSPs) that were affected by repeat-induced point mutations (RIP). An active RIP mechanism was revealed by lack of repeats, dinucleotide bias in repeats and genes, low proportion of recent gene duplicates, and reduction of recent gene family expansions. The high expression and rapid divergence of SSPs indicate a striking similarity in the infection mechanisms of nematode-trapping fungi and plant and insect pathogens from the crown groups of the filamentous ascomycetes (Pezizomycotina). The patterns of gene family expansions in the nematode-trapping fungi were more similar to plant pathogens than to insect and animal pathogens. The observation of RIP activity in the Orbiliomycetes suggested that this mechanism was present early in the evolution of the filamentous ascomycetes. PMID:24244185

  8. Nematodes of the large intestine of the European bison of the Bia?owieza National Park.

    PubMed

    Demiaszkiewicz, Aleksander W; Pyziel, Anna M; Kuligowska, Izabela; Lachowicz, Jacek; Krzysiak, Micha? K

    2012-01-01

    The present study was conducted on 31 males and females of the European bison, eliminated during the winter seasons 2007-2011 in the Bia?owieza Primeval Forest, Poland. The caeca of 14 free-ranging bison, aged from 3 months up to 16 years, the most favorable infection site for the large intestine nematodes, were investigated during the winter of 2007/2008. The parasitological autopsies of the large intestines of 9 free-ranging bison aged from 5 months up to 10 years as well as 9 bison kept in the close reserves aged from one up to 20 years were done during the winter seasons of 2008-2011 to determine localization of nematodes in large intestine and the total intensity of parasite infection. Five species of nematodes (i.e., Trichuris ovis, Oesophagostomum venulosum, O. radiatum, Ashworthius sidemi, Nematodirus helvetianus) were found in dissected caecum of bison culled during the winter of 2007/2008. During the seasons of 2008-2010, 6 species of nematodes were found in the large intestine of bison (i.e., T. ovis, O. venulosum, O. radiatum, A. sidemi, N. roscidus and Bunostomum trigonocephalum). We did not find any nematodes in the lumen of the large intestine of captive bison culled during the seasons of 2010/2011. The results of the present study indicate that the intensity of infection by the large intestine nematodes of the European bison in the Bia?owieza Primeval Forest has stayed at the comparable level throughout the last 20 years; however the number of nematode species has increased. The observed level of parasitic infection is typical of subclinical parasitoses. PMID:23094330

  9. Influence of chemosynthetic ecosystems on nematode community structure and biomass in the deep eastern Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Lampadariou, N.; Kalogeropoulou, V.; Sevastou, K.; Keklikoglou, K.; Sarrazin, J.

    2012-12-01

    Mud volcanoes are a special type of cold seeps where life is based on chemoautotrophic processes. They are considered as extreme environments and are characterised by unique megafaunal and macrofaunal communities. However, very few studies on mud volcanoes taking into account the smaller meiobenthic communities have been carried out. Two mud volcanoes were explored during the MEDECO cruise (2007) with the Remotely Operated Vehicle (ROV) Victor-6000; Amsterdam, located south of Turkey between 1700 and 2000 m depth (Anaximander mud field) and Napoli, south of Crete, located along the Mediterranean Ridge at about 2000 m depth (Olimpi mud field). The major aim of this study was to describe distributional patterns of meiofaunal communities and nematode assemblages from different seep microhabitats. Meiofaunal taxa and nematode assemblages at both mud volcanoes differed significantly from other Mediterranean sites in terms of standing stocks, dominance and species diversity. Density and biomass values were significantly higher at the seep sites, particularly at Amsterdam. Nematodes, the dominant meiofaunal taxon, displayed deeper penetration vertically into the sediment at the seep areas, indicating that biological rather than physicochemical factors are responsible for their vertical distribution. Patterns of nematode diversity varied, displaying both very high or very low species richness and dominance, depending on the habitat studied. The Lamellibrachia periphery and mussel bed of Napoli exhibited the highest species richness while the reduced sediments of Amsterdam yielded a species-poor nematode community, dominated by two successful species; one belonging to the genus Aponema and the other to the genus Sabatieria. Analysis of ?-diversity showed that habitat heterogeneity of mud volcanoes contributed substantially to the total nematode species richness in the eastern Mediterranean Sea. These observations indicate a strong influence of mud volcanoes and cold-seep ecosystems on the meiofaunal communities and nematode assemblages.

  10. Contrasting diversity patterns of soil mites and nematodes in secondary succession

    SciTech Connect

    Kardol, Paul [ORNL; Newton, Jeffrey S. [University of Alberta, Edmondton, Canada; Bezemer, T Martijn [Netherlands Institute of Ecology (NIOO-KNAW); Maraun, Mark [University of Gottingen, Germany; van der Putten, Wim H. [Netherlands Institute of Ecology (NIOO-KNAW)

    2009-01-01

    Soil biodiversity has been recognized as a key feature of ecosystem functioning and stability. However, soil biodiversity is strongly impaired by agriculture and relatively little is known on how and at what spatial and temporal scales soil biodiversity is restored after the human disturbances have come to an end. Here, a multi-scale approach was used to compare diversity patterns of soil mites and nematodes at four stages (early, mid, late, reference site) along a secondary succession chronosequence from abandoned arable land to heath land. In each field four soil samples were taken during four successive seasons. We determined soil diversity within samples ({alpha}-diversity), between samples ({beta}-diversity) and within field sites ({gamma}-diversity). The patterns of {alpha}- and {gamma}-diversity developed similarly along the chronosequence for oribatid mites, but not for nematodes. Nematode {alpha}-diversity was highest in mid- and late-successional sites, while {gamma}-diversity was constant along the chronosequence. Oribatid mite {beta}-diversity was initially high, but decreased thereafter, whereas nematode {beta}-diversity increased when succession proceeded; indicating that patterns of within-site heterogeneity diverged for oribatid mites and nematodes. The spatio-temporal diversity patterns after land abandonment suggest that oribatid mite community development depends predominantly on colonization of new taxa, whereas nematode community development depends on shifts in dominance patterns. This would imply that at old fields diversity patterns of oribatid mites are mainly controlled by dispersal, whereas diversity patterns of nematodes are mainly controlled by changing abiotic or biotic soil conditions. Our study shows that the restoration of soil biodiversity along secondary successional gradients can be both scale- and phylum-dependent.

  11. Extension of the established period of diacetyl adaptation by oxygen intermediates in the nematode Caenorhabditis elegans.

    PubMed

    Nishino, Asuka; Sato, Fumihiko; Ito, Kuniko; Matsuura, Tetsuya

    2015-06-01

    After pre-exposure to the odorant diacetyl, the nematode Caenorhabditis elegans showed a decline in chemotactic responses to diacetyl, a phenomenon known as diacetyl adaptation. In the present study, we found that the established period of diacetyl adaptation in nematodes increased with the breeding temperature. When wild-type (N2) nematodes were bred at 15°C, adaptation was observed from the young adult (YA) to the 3-day-old adult that is reached 3 days after the YA stage. On breeding nematodes at 20°C and 25°C, adaptation was observed between the YA and 5-day-old adult and between the YA and the 7-day-old adult, respectively. Breeding temperature has been shown to correlate with the rate of aging in nematodes, which is related to the level of oxygen consumption. Accordingly, long-lived isp-1 and clk-1 mutants that demonstrate decreased levels of oxygen consumption showed a shorter established period of adaptation than N2 nematodes, whereas short-lived gas-1 and mev-1 mutants that have a hypersensitive response to oxygen showed a longer period of adaptation than the N2. Moreover, the established period of diacetyl adaptation in N2 nematodes was shortened by the antioxidant ?-lipoic acid. These results suggest that oxygen intermediates, which are produced by oxygen consumption, play a significant role in diacetyl adaptation. Although this is only one of many factors that regulate diacetyl adaptation, such as the release of neurotransmitters and changes in intracellular conditions, the acquisition of this adaptation requires an increase in the intensity of moderate oxygen signals. PMID:25759262

  12. The Potato Pathotype of the False-Root Knot Nematode, Nacobbus aberrans Working Group of the SON Exotic Nematode Plant Pest List

    Microsoft Academic Search

    R. N. Inserra; J. J. Chitambar; D. J. Chitwood; Z. Handoo

    The false root-knot nematode, Nacobbus aberrans, is a species complex with many pathotypes having different host preference. This species is native in the United States, where it is a damaging pest of sugarbeet. Native hosts parasitized by N. aberrans in the United States have favored the specialization of N. aberrans populations to infect sugarbeet. These populations are named the sugarbeet

  13. The majority of parasitic worms belong to either the Platyhelminthes (flatworms/flukes and tape-worms) or Nematoda (roundworms/nematodes).

    E-print Network

    Jawitz, James W.

    The majority of parasitic worms belong to either the Platyhelminthes (flatworms/flukes and tape- worms) or Nematoda (roundworms/nematodes). Unlike earthworms, nematodes are un becomes capable of reproducing (eggs produced after male worm inseminates female). In some instances

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

    PubMed Central

    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

  15. The development and utilization of an in vivo RNA interference protocol to elucidate gene functions and identify potential drug targets in the filarial nematode Brugia malayi

    Microsoft Academic Search

    Chuanzhe Song

    2011-01-01

    Since its first characterization in 1998 in the free-living nematode Caenorhabditis elegans, RNA interference has been considered a powerful reverse genetics tool to investigate nematode biology. But to date, current RNAi protocols for parasitic nematodes have proven unreliable and inconsistent.\\u000aWe established an alternative RNAi protocol targeting the filarial nematode Brugia malayi in-host whereby the parasites are exposed to RNAi

  16. The Genetics of Levamisole Resistance in the Nematode CAENORHABDITIS ELEGANS

    PubMed Central

    Lewis, James A.; Wu, C.-H.; Berg, Howard; Levine, Joseph H.

    1980-01-01

    We have characterized a small group of genes (13 loci) in the nematode Caenorhabditis elegans that, when mutated, confer resistance to the potent anthelmintic levamisole. Mutants at the 7 loci conferring the most extreme resistance generally possess almost identical visible and pharmacological phenotypes: uncoordinated motor behavior, most severe in early larval life, extreme resistance to cholinergic agonists and sensitivity to hypo-osmotic shock. Mutants with exceptional phenotypes suggest possible functions for several of the resistance loci. The most extreme mutants can readily be selected by their drug resistance (211 mutants, as many as 74 alleles of one gene). The more common resistance loci are likely to be unessential genes, while loci identified by only a few alleles may be essential genes or genes conferring resistance only when mutated in a special way. We propose that these mutants represent a favorable system for understanding how a small group of related genes function in a simple animal. The extreme drug resistance of these mutants makes them useful tools for the genetic manipulation of C. elegans. And, as the most resistant class of mutants might lack pharmacologically functional acetylcholine receptors (Lewis et al. 1980), these mutants may also be of some neurobiological significance. PMID:7203008

  17. Grazing sericea lespedeza for control of gastrointestinal nematodes in lambs.

    PubMed

    Burke, J M; Miller, J E; Mosjidis, J A; Terrill, T H

    2012-05-25

    Alternatives to chemical dewormers are needed to counter anthelmintic resistance and improve worm control in organic management systems. The objective was to examine the effectiveness of grazing sericea lespedeza (SL) compared with grass pastures for control of gastrointestinal nematodes (GIN) in lambs. In Experiment 1, Katahdin lambs grazed bermudagrass (BG; n=14), tall fescue (TF; n=7), or SL (n=19) pastures during early summer months. In Experiment 2, lambs grazed TF (n=15) or SL (n=13) pastures during late summer. Stocking rate of pastures was based on forage availability; additional lambs grazed pastures in Experiment 2, but were not sampled. Lambs were dewormed with 0.5 g COWP if FAMACHA(©) score was >3. In Experiment 1, FEC were reduced within 35 days in SL compared with BG lambs (forage by time, P=0.03). The PCV was more resilient to changes over time in SL compared with other groups of lambs (forage by time, P=0.001). In Experiment 2, FEC were lower (P=0.02) and PCV tended to be higher (P=0.09) in lambs grazing SL compared with TF forage. Incidence of deworming was similar among forage groups in both experiments. Grazing SL reduced FEC in lambs in early and late summer, despite reluctance by lambs to graze. Grazing forage and selective deworming using COWP was effective in lambs. PMID:22226762

  18. Characterization of Bacteria Associated with Pinewood Nematode Bursaphelenchus xylophilus

    PubMed Central

    Vicente, Claudia S. L.; Nascimento, Francisco; Espada, Margarida; Barbosa, Pedro; Mota, Manuel; Glick, Bernard R.; Oliveira, Solange

    2012-01-01

    Pine wilt disease (PWD) is a complex disease integrating three major agents: the pathogenic agent, the pinewood nematode Bursaphelenchus xylophilus; the insect-vector Monochamus spp.; and the host pine tree, Pinus sp. Since the early 80's, the notion that another pathogenic agent, namely bacteria, may play a role in PWD has been gaining traction, however the role of bacteria in PWD is still unknown. The present work supports the possibility that some B. xylophilus-associated bacteria may play a significant role in the development of this disease. This is inferred as a consequence of: (i) the phenotypic characterization of a collection of 35 isolates of B. xylophilus-associated bacteria, in different tests broadly used to test plant pathogenic and plant growth promoting bacteria, and (ii) greenhouse experiments that infer the pathogenicity of these bacteria in maritime pine, Pinus pinaster. The results illustrate the presence of a heterogeneous microbial community associated with B. xylophilus and the traits exhibited by at least, some of these bacteria, appear to be related to PWD symptoms. The inoculation of four specific B. xylophilus-associated bacteria isolates in P. pinaster seedlings resulted in the development of some PWD symptoms suggesting that these bacteria likely play an active role with B. xylophilus in PWD. PMID:23091599

  19. Grower Acceptance of Entomopathogenic Nematodes: Case Studies on Three Continents

    PubMed Central

    Dolinski, C.; Choo, H.Y.

    2012-01-01

    Projects to manage arthropod pests using entomopathogenic nematodes (EPNs) in Brazil, Korea and USA are reviewed to identify conditions and practices that affected the use of EPNs for pest management. A proliferation of covered agriculture in Korea, the growth in demand for high value, pesticide-free produce in Korea and Brazil, and the cost-effectiveness of EPNs created favorable conditions for the widespread adoption of EPN products in Brazilian guava orchards and Korean vegetable greenhouses. In Florida, EPNs imported from South America function successfully as classical biocontrol agents against invasive mole crickets attacking pasture and turf. However, the low value of pasture and the availability of cost-effective chemical insecticides in turf have depressed the demand for EPN products to control mole crickets. In Florida citrus orchards, a recent, dramatic increase in the use of chemical insecticides to control an arthropod vector of a devastating bacterial disease of citrus (huanglongbing) reduced the demand for EPN products to control Diaprepes root weevils. Nevertheless, a rich and diverse EPN fauna in the Florida peninsula provides significant control of subterranean stages of root weevils in some habitats, and is the focus of research to develop cultural practices that exploit the potential for increased pest management through EPN conservation. PMID:23482423

  20. An explicit immunogenetic model of gastrointestinal nematode infection in sheep

    PubMed Central

    Prada Jiménez de Cisneros, Joaquín; Stear, Michael J.; Mair, Colette; Singleton, Darran; Stefan, Thorsten; Stear, Abigail; Marion, Glenn; Matthews, Louise

    2014-01-01

    Gastrointestinal nematodes are a global cause of disease and death in humans, wildlife and livestock. Livestock infection has historically been controlled with anthelmintic drugs, but the development of resistance means that alternative controls are needed. The most promising alternatives are vaccination, nutritional supplementation and selective breeding, all of which act by enhancing the immune response. Currently, control planning is hampered by reliance on the faecal egg count (FEC), which suffers from low accuracy and a nonlinear and indirect relationship with infection intensity and host immune responses. We address this gap by using extensive parasitological, immunological and genetic data on the sheep–Teladorsagia circumcincta interaction to create an immunologically explicit model of infection dynamics in a sheep flock that links host genetic variation with variation in the two key immune responses to predict the observed parasitological measures. Using our model, we show that the immune responses are highly heritable and by comparing selective breeding based on low FECs versus high plasma IgA responses, we show that the immune markers are a much improved measure of host resistance. In summary, we have created a model of host–parasite infections that explicitly captures the development of the adaptive immune response and show that by integrating genetic, immunological and parasitological understanding we can identify new immune-based markers for diagnosis and control. PMID:25121649

  1. Pinewood Nematode Species Complex: Interbreeding Potential and Chromosome Number

    PubMed Central

    Bolla, R. I.; Boschert, M.

    1993-01-01

    Interbreeding potential, chromosome number, and host range were compared among several isolates and species of Bursaphelenchus from diverse geographic areas. Some isolates from North America, Japan, and France had a wide-ranging interbreeding potential, whereas others were restricted in their potential to hybridize with other isolates. Although interbreeding occurred in the laboratory between some "M" and "R" forms of B. xylophilus, interbreeding of B. xylophilus and B. mucronatus was rare. The hybrids had the pathogenicity of the parent with the broader host range. This fact suggests that virulence may be inherited as a dominant character or that increased virulence may have resulted from differences in hybrid vigor. The haploid chromosome number of the different isolates separated the isolates into three groups and distinguished B. xylophilus from B. mucronatus. The findings suggest that the pinewood nematode species complex consists of sibling species that have evolved by reproductive isolation, that the French isolate is a new species, and that B. xylophilus and B. mucronatus have evolved from a common ancestor. PMID:19279762

  2. Wild deer as potential vectors of anthelmintic-resistant abomasal nematodes between cattle and sheep farms.

    PubMed

    Chintoan-Uta, C; Morgan, E R; Skuce, P J; Coles, G C

    2014-04-01

    Gastrointestinal (GI) nematodes are among the most important causes of production loss in farmed ruminants, and anthelmintic resistance is emerging globally. We hypothesized that wild deer could potentially act as reservoirs of anthelmintic-resistant GI nematodes between livestock farms. Adult abomasal nematodes and faecal samples were collected from fallow (n = 24), red (n = 14) and roe deer (n = 10) from venison farms and areas of extensive or intensive livestock farming. Principal components analysis of abomasal nematode species composition revealed differences between wild roe deer grazing in the areas of intensive livestock farming, and fallow and red deer in all environments. Alleles for benzimidazole (BZ) resistance were identified in ?-tubulin of Haemonchus contortus of roe deer and phenotypic resistance confirmed in vitro by an egg hatch test (EC50 = 0.149 µg ml(-1) ± 0.13 µg ml(-1)) on H. contortus eggs from experimentally infected sheep. This BZ-resistant H. contortus isolate also infected a calf experimentally. We present the first account of in vitro BZ resistance in wild roe deer, but further experiments should firmly establish the presence of phenotypic BZ resistance in vivo. Comprehensive in-field studies should assess whether nematode cross-transmission between deer and livestock occurs and contributes, in any way, to the development of resistance on livestock farms. PMID:24552838

  3. Long-term Disturbance Effects in the Nematode Communities of South Mississippi Woodlands

    PubMed Central

    Thornton, C. W.; Matlack, G. R.

    2002-01-01

    The effects of soil disturbance on the nematode community were assessed at 30 sites on the outer coastal plain of Mississippi, representing four ages since soil disturbance plus a control group of six undisturbed sites. Thirty-five taxa were encountered, dominated in abundance and taxonomic richness by plant and bacterial feeders. Nematodes were more abundant and more taxonomically rich in sites with a low slope and deep litter cover, distant from trees. Plant feeders were more numerous at sites with a dense herb cover, suggesting limitation by food availability. When sites were arranged as a chronosequence, herb cover, litter depth, soil organic matter, soil moisture, and tree canopy cover increased through time consistent with succession to forest. The abundance of most trophic groups decreased in the 10 to 20 years following disturbance and increased thereafter, a pattern repeated in taxonomic richness of plant and bacterial feeders. Fifty years after disturbance, nematode abundance had not returned to levels observed in control sites. These results suggest that nematode succession following soil disturbance is a gradual process regulated by establishment of aboveground vegetation. There was no evidence of dispersal limitation or facilitation by colonist nematode species. PMID:19265914

  4. Sensitive and reliable detection of grapevine fanleaf virus in a single Xiphinema index nematode vector.

    PubMed

    Demangeat, Gérard; Komar, Véronique; Cornuet, Pascal; Esmenjaud, Daniel; Fuchs, Marc

    2004-12-01

    Grapevine fanleaf virus (GFLV) is specifically transmitted from plant to plant by the ectoparasitic nematode Xiphinema index. A sensitive and reliable procedure was developed to readily detect GFLV in a single viruliferous X. index, regardless of the nematode origin, i.e. greenhouse rearings or vineyard soils. The assay is based on bead milling to disrupt nematodes extracted from soil samples, solid-phase extraction of total nematode RNAs, and amplification of a 555bp fragment of the coat protein (CP) gene by reverse transcription-polymerase chain reaction with two primers designed from conserved sequences. This procedure is sensitive since the CP gene fragment is amplified from an artificial sample consisting of one viruliferous nematode mixed with 3000 aviruliferous individuals. In addition, StyI RFLP analysis of the CP amplicon enables the GFLV isolate carried by a single viruliferous X. index to be characterized. This GFLV detection assay opens new avenues for epidemiological studies and for molecular investigations on the mechanism of X. index-mediated GFLV transmission. PMID:15488624

  5. Effects of Tagetes patula on Active and Inactive Stages of Root-Knot Nematodes.

    PubMed

    Marahatta, Sharadchandra P; Wang, Koon-Hui; Sipes, Brent S; Hooks, Cerruti R R

    2012-03-01

    Although marigold (Tagetes patula) is known to produce allelopathic compounds toxic to plant-parasitic nematodes, suppression of Meloidogyne incognita can be inconsistent. Two greenhouse experiments were conducted to test whether marigold is more effective in suppressing Meloidogyne spp. when it is active rather than dormant. Soils infested with Meloidogyne spp. were collected and conditioned in the greenhouse either by 1) keeping the soil dry (DRY), 2) irrigating with water (IRR), or 3) drenching with cucumber (Cucumis sativus) leachate (CL) for 5 wk. These soils were then either planted with cucumber, marigold or remained bare for 10 wk. Suppression of nematode by marigold was then assayed using cucumber. DRY conditioning resulted in the highest number of inactive nematodes, whereas CL and IRR had higher numbers of active nematodes than DRY. At the end of the cucumber bioassay, marigold suppressed the numbers of Meloidogyne females in cucumber roots if the soil was conditioned in IRR or CL, but not in DRY. However, in separate laboratory assays, marigold root leachate slightly reduced M. incognita J2 activity but did not reduce egg hatch (P > 0.05). These finding suggest that marigold can only suppress Meloidogyne spp. when marigold is actively growing. This further suggests that marigold will more efficiently suppress Meloidogyne spp. if planted when these nematodes are in active stage. PMID:23482862

  6. Transgenerational effects of traffic-related fine particulate matter (PM?.?) on nematode Caenorhabditis elegans.

    PubMed

    Zhao, Yunli; Lin, Zhiqing; Jia, Ruhan; Li, Guojun; Xi, Zhuge; Wang, Dayong

    2014-06-15

    Numerous studies have demonstrated the toxic effects of fine particle matter less than 2.5 ?m (PM2.5) on health of human. However, little information is available on PM2.5 ecotoxicity. We employed Caenorhabditis elegans to investigate the adverse effects of traffic-related PM2.5 on exposed animals and their progeny. Acute exposure to high concentrations of PM2.5 in the range of mg/L caused adverse effects on development, lifespan, reproduction, and locomotion behavior of nematodes. In contrast, prolonged exposure to low concentrations of PM2.5 in the range of ?g/L resulted in adverse effects on development, lifespan, reproduction, locomotion behavior, and intestinal development of nematodes. Prolonged exposure to PM2.5 could even cause adverse effects on lifespan, reproduction, locomotion behavior, and intestinal development in progeny of exposed nematodes. PM2.5 toxicity was only partially recovered in progeny of exposed nematodes. For the PM2.5 toxicity on nematodes and their progeny, we hypothesize that it might be the combinational effects of oxidative stress, damage on intestinal barrier, and abnormal defecation behavior. Our data here imply the potential toxic effects of long-term exposure to traffic-related PM2.5 on environmental organisms. Our results further highlight the possible crucial roles of biological barrier and defecation behavior in regulating the PM2.5 toxicity. PMID:24769847

  7. Catalases Induction in High Virulence Pinewood Nematode Bursaphelenchus xylophilus under Hydrogen Peroxide-Induced Stress

    PubMed Central

    Vicente, Cláudia S. L.; Ikuyo, Yoriko; Shinya, Ryoji; Mota, Manuel; Hasegawa, Koichi

    2015-01-01

    Considered an EPPO A2 quarantine pest, Bursaphelenchus xylophilus is the causal agent of the pine wilt disease and the most devastating plant parasitic nematode attacking coniferous trees in the world. In the early stages of invasion, this nematode has to manage host defence mechanisms, such as strong oxidative stress. Only successful, virulent nematodes are able to tolerate the basal plant defences, and furthermore migrate and proliferate inside of the host tree. In this work, our main objective was to understand to what extent B. xylophilus catalases are involved in their tolerance to oxidative stress and virulence, using as oxidant agent the reactive oxygen species hydrogen peroxide (H2O2). After 24 hours of exposure, high virulence isolates of B. xylophilus could withstand higher H2O2 concentrations in comparison with low virulence B. xylophilus and B. mucronatus, corroborating our observation of Bxy-ctl-1 and Bxy-ctl-2 catalase up-regulation under the same experimental conditions. Both catalases are expressed throughout the nematode intestine. In addition, transgenic strains of Caenorhabditis elegans overexpressing B. xylophilus catalases were constructed and evaluated for survival under similar conditions as previously. Our results suggest that catalases of high virulence B. xylophilus were crucial for nematode survival under prolonged exposure to in vitro oxidative stress, highlighting their adaptive response, which could contribute to their success in host conditions. PMID:25894519

  8. Wild deer as potential vectors of anthelmintic-resistant abomasal nematodes between cattle and sheep farms

    PubMed Central

    Chintoan-Uta, C.; Morgan, E. R.; Skuce, P. J.; Coles, G. C.

    2014-01-01

    Gastrointestinal (GI) nematodes are among the most important causes of production loss in farmed ruminants, and anthelmintic resistance is emerging globally. We hypothesized that wild deer could potentially act as reservoirs of anthelmintic-resistant GI nematodes between livestock farms. Adult abomasal nematodes and faecal samples were collected from fallow (n = 24), red (n = 14) and roe deer (n = 10) from venison farms and areas of extensive or intensive livestock farming. Principal components analysis of abomasal nematode species composition revealed differences between wild roe deer grazing in the areas of intensive livestock farming, and fallow and red deer in all environments. Alleles for benzimidazole (BZ) resistance were identified in ?-tubulin of Haemonchus contortus of roe deer and phenotypic resistance confirmed in vitro by an egg hatch test (EC50 = 0.149 µg ml?1 ± 0.13 µg ml?1) on H. contortus eggs from experimentally infected sheep. This BZ-resistant H. contortus isolate also infected a calf experimentally. We present the first account of in vitro BZ resistance in wild roe deer, but further experiments should firmly establish the presence of phenotypic BZ resistance in vivo. Comprehensive in-field studies should assess whether nematode cross-transmission between deer and livestock occurs and contributes, in any way, to the development of resistance on livestock farms. PMID:24552838

  9. Meiobenthos of the central Arctic Ocean with special emphasis on the nematode community structure

    NASA Astrophysics Data System (ADS)

    Vanreusel, Ann; Clough, Lisa; Jacobsen, Kim; Ambrose, William; Jivaluk, Jutamas; Ryheul, Valerie; Herman, Rudy; Vincx, Magda

    2000-10-01

    We investigated the abundance of the meiobenthos and the biomass and community structure of the nematodes in the central Arctic Ocean along two separate transects during 1991 and 1994. Meiobenthos abundances ranged from <100 to 600 individuals per 10 cm 2, in the same order of magnitude as in other oligotrophic areas of the world's deep ocean. Nematodes were the numerically dominant meiofaunal group at every station. Nematode biomass ranged from <1 to 48 ?g dry weight per 10 cm 2. A combination of water depth and latitude explained 55% of the variability among stations in nematode biomass and 67% of the variability of total abundance, implying that both vertical and advective fluxes are important sources of food to the meiofaunal communities.The dominant nematode genus was Monhystera, a detrivorous/bacterivorous deposit feeder, suggesting that bacteria may play an important role in the food web of the meiobenthos in the Central Arctic. Multivariate analysis of genera abundances revealed differences among stations in the Eurasian and Amerasian Basins. During 1994, however, the deep stations in the Eurasian Basin were more similar to the other Amerasian stations, while the single deep station in the Makarov Basin was most similar to the other Eurasian Basin stations. The structure of meiofaunal communities in the central Arctic may provide insight into spatial variability in the Arctic Ocean.

  10. The alpha and beta subunits of nematode actin capping protein function in yeast.

    PubMed Central

    Waddle, J A; Cooper, J A; Waterston, R H

    1993-01-01

    We cloned and analyzed two genes, cap-1 and cap-2, which encode the alpha and beta subunits of Caenorhabditis elegans capping protein (CP). The nematode CP subunits are 55% (cap-1) and 66% (cap-2) identical to the chicken CP subunits and 32% (cap-1) and 48% (cap-2) identical to the yeast CP subunits. Purified nematode CP made by expression of both subunits in yeast is functionally similar to chicken skeletal muscle CP in two different actin polymerization assays. The abnormal cell morphology and disorganized actin cytoskeleton of yeast CP null mutants are restored to wild-type by expression of the nematode CP subunits. Expression of the nematode CP alpha or beta subunit is sufficient to restore viability to yeast cap1 sac6 or cap2 sac6 double mutants, respectively. Therefore, despite evolution of the nematode actin cytoskeleton to a state far more complex than that of yeast, one important component can function in both organisms. Images PMID:8257793

  11. Effect of white grub developmental stage on susceptibility to entomopathogenic nematodes.

    PubMed

    Koppenhöfer, Albrecht M; Fuzy, Eugene M

    2004-12-01

    The pathogenicity of the entomopathogenic nematodes Heterorhabditis bacteriophora Poinar and Steinernema scarabaei Stock & Koppenhöfer against different developmental stages of the Japanese beetle, Popillia japonica Newman, and the oriental beetle, Anomala (=Exomala) orientalis Waterhouse, were studied under laboratory conditions. The efficacy of S. scarabaei did not differ between second and third instars in P. japonica or A. orientalis or between small (young) and large (older) third instars in A. orientalis. However, H. bacteriophora efficacy decreased from first over second to third instar and also from small third instars to large third instars in A. orientalis but did not differ significantly between P. japonica larval stages. Once A. orientalis third instars had purged their intestines in preparation for pupation, no significant mortality by S. scarabaei and H. bacteriophora was observed. In contrast, P. japonica susceptibility to both nematode species gradually decreased from stage to stage from actively feeding third instars to pupae. In two additional experiments, we found no difference in Steinernema glaseri (Steiner) susceptibility between second and third instars of A. orientalis but an increase in S. scarabaei susceptibility from the second to third instar of Asiatic garden beetle, Maladera castanea (Arrow). Our observations combined with those of previous studies with other nematode and white grub species show that nematode efficacy against white grub developmental stages varies with white grub and nematodes species, and no generalization can be made. PMID:15666735

  12. Two closely related members of Arabidopsis 13-LOXs, LOX3 and LOX4, reveal distinct functions in response to plantparasitic nematode infection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The responses of two closely related members of Arabidopsis 13-lipoxygenase (13-LOX), LOX3 and LOX4, to infection by the sedentary nematodes root-knot nematode (Meloidogyne javanica) and cyst nematode (Heterodera schachtii) were analyzed in transgenic Arabidopsis seedlings. Tissue localization of LO...

  13. The significance of ecology in the development of Verticillium chlamydosporium as a biological agent against root-knot nematodes (Meloidogyne spp.)

    Microsoft Academic Search

    Leij de F. A. A. M

    1992-01-01

    A thorough understanding of the interactions which occur between nematode parasites and nematode pests and the influence of biotic and abiotic factors on these interactions, is essential in the development of biological control agents for nematodes. The aim of this study was to develop a particular isolate of the nematophagous fungus Verticillium chlamydosporium as a biological control agent for root-knot

  14. Microhabitat type determines the composition of nematode communities associated with sediment-clogged cold-water coral framework in the Porcupine Seabight (NE Atlantic)

    Microsoft Academic Search

    M. Raes; A. Vanreusel

    2006-01-01

    The nematofauna associated with a cold-water coral degradation zone in the Porcupine Seabight (NE Atlantic) was investigated. This is the first comprehensive study of nematodes associated with cold-water corals. This research mainly aimed to investigate the influence of microhabitat type on nematode community structure. Three distinct microhabitats for nematodes were distinguished: dead coral fragments, glass sponge skeletons and the underlying

  15. The role of cell wall-modifying proteins in plant penetration and feeding site proliferation by the potato cyst nematode Globodera rostochiensis

    Microsoft Academic Search

    U. Kudla

    2006-01-01

    The main objective of this thesis was to investigate two distinct groups of proteins involved in plant cell walls modifications in the parasitism of the potato cyst nematode, Globodera rostochiensis , namely pectate lyases and expansins. Plant parasitism of potato cyst nematode proceeds through two main stages i.e. mobile and sessile. During the migratory phase, potato cyst nematode uses cell

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  17. RESISTANCE OF WATERMELON (CITRULLUS SPP.) GERMPLASM TO THE PEANUT ROOT-KNOT NEMATODE (MELOIDOGYNE ARENARIA RACE 1)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Root-knot nematodes (Meloidogyne arenaria, M. incognita, and M. javanica) are serious pests of watermelon (Citrullus lanatus) in the southern U.S. and world-wide. Currently, root-knot nematodes (RKN) are controlled in watermelon by pre-plant soil fumigation with methyl bromide or other nematicides....

  18. Site-Specific Nematode Management for Potatoes in Idaho Using 1,3-Dichloropropene; Experiences and Economics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fumigation for nematode management in irrigated potato production systems of Idaho is widely practiced. Spatially uniform fumigation with large scale soil injection equipment is the only labeled application method for 1,3-dichloropropene. Plant-parasitic nematode species exhibit spatially variable p...

  19. A novel mechanism of gene regulation identified in the chorismate mutase gene from the potato cyst nematode Globodera rostochiensis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Alternative pre-mRNA splicing, a widely used means to control gene expression in eukaryotic organisms, has not been documented in plant parasitic nematodes. Here we report that a chorismate mutase gene (GrCM1) expressed exclusively within the subventral gland cells of the potato cyst nematode Golob...

  20. Chorismate mutase: an alternatively spliced parasitism gene and a diagnostic marker for three important Globodera nematode species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The chorismate mutase gene is widely distributed in both cyst and root-knot nematode species and believed to play a critical role in nematode parasitism. In this study, we cloned a new chorismate mutase gene (Gt-cm-1) from Globodera tabacum and further characterized the gene structure in both G. tab...