Academic literature on the topic 'Nematoda'
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Journal articles on the topic "Nematoda"
1
Indarti, Siwi, Arif Wibowo, Siti Subandiyah, and Miftahul Ajri. "First Record: A Stem and Bulb Plant Parasitic Nematode at Garlic Area Centre Temanggung, Central Java, Indonesia with Species Reference to Ditylenchus dipsaci." Jurnal Perlindungan Tanaman Indonesia 22, no. 2 (November 15, 2018): 233. http://dx.doi.org/10.22146/jpti.35321.
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A survey to investigate the stem and bulb plant parasitic nematode at one of garlic area centre, in Temanggung, Central Java, Indonesia was conducted from Januaryto February 2018. Infected plant with specific symptoms, morphological and morphometric characters both of female and male of adult nematodes were used to describe a A1 quarantine plant parasitic nematode Ditylenchus dipsaci. Seven from nine observed locations were postively infected with population in average 2.67 nematodes per 100 g of soil and 2.67–189.33 per bulb. This is the first report of D. dipsaci from Indonesia and consequently further investigations were needed to know their distribution and also to confirm the origin of the nematode. IntisariSurvei keberadaan nematoda parasit batang dan umbi dilakukan pada bulan Januari–Februari 2018 pada satu sentra penangkaran bawang putih di Temanggung, Jawa Tengah, Indonesia. Tanaman terinfeksi dengan gejala serangan yang spesifik, karakter morfologi dan morfometri nematoda betina dan jantan dewasa dipergunakan dalam identifikasi Ditylenchus dipsaci yang merupakan nematoda parasit tanaman yang termasuk OPTK A1 (Organisme Pengganggu Tanaman Karantina A1) di Indonesia. Sebanyak tujuh dari sembilan lokasi yang diamati mengindikasikan positif sebagai daerah sebaran nematoda tersebut dengan populasi rata-rata 2,67 ekor per 100 gram tanah dan 2,67–189,33 nematoda per umbi. Laporan pertama tentang nematoda D. dipsaci ini membawa konsekuensi perlunya penelitian lebih lanjut untuk mengetahui daerah sebaran dan juga konfirmasi dari mana nematoda tersebut berasal.
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Indrayati, Liestiana. "INVENTARISASI NEMATODA PARASIT PADA TANAMAN, HEWAN DAN MANUSIA." EnviroScienteae 13, no. 3 (December 20, 2017): 195. http://dx.doi.org/10.20527/es.v13i3.4306.
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Pathogenic nematodas are widespread in nature, it can attack plants, animals, and humans and cause disruption to their hosts, then effect to lower quantity of plantation, yields, and livestock production and also affect to degradation of human resource quality. This paper is a systematic review that uses literature method about the inventory of nematoda parasite that attacks plants, animals and human, some method of examination and the effects that occurred by the host. The major parasite nematodas that infect the plants are Meloidogyne sp, Pratylenchut sp, and Radopholus sp., nematode in animals are Strongyloides spp., Haemonchus spp., Oesophagosomum spp., and Trichostrongyloides spp. In the fish variant, Anisakis spp, and nematode in humans are Ascaris lumbricoides, Trichuris trichiura, and hookworm. Some animal nematodas were found to attack humans whereas plant nematodas have not been reported to be found in humans or animals. Nematoda control is by anthelmintic consumption, environmental modification, personal hygiene and the use of biological agents.
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Irvine, Allister, Sharon A. Huws, Louise E. Atkinson, and Angela Mousley. "Exploring the antimicrobial peptidome of nematodes through phylum-spanning in silico analyses highlights novel opportunities for pathogen control." PLOS Neglected Tropical Diseases 17, no. 9 (September 6, 2023): e0011618. http://dx.doi.org/10.1371/journal.pntd.0011618.
Full textAbstract:
Antimicrobial Peptides (AMPs) are key constituents of the invertebrate innate immune system and provide critical protection against microbial threat. Nematodes display diverse life strategies where they are exposed to heterogenous, microbe rich, environments highlighting their need for an innate immune system. Within the Ecdysozoa, arthropod AMPs have been well characterised, however nematode-derived AMP knowledge is limited. In this study the distribution and abundance of putative AMP-encoding genes was examined in 134 nematode genomes providing the most comprehensive profile of AMP candidates within phylum Nematoda. Through genome and transcriptome analyses we reveal that phylum Nematoda is a rich source of putative AMP diversity and demonstrate (i) putative AMP group profiles that are influenced by nematode lifestyle where free-living nematodes appear to display enriched putative AMP profiles relative to parasitic species; (ii) major differences in the putative AMP profiles between nematode clades where Clade 9/V and 10/IV species possess expanded putative AMP repertoires; (iii) AMP groups with highly restricted profiles (e.g. Cecropins and Diapausins) and others [e.g. Nemapores and Glycine Rich Secreted Peptides (GRSPs)] which are more widely distributed; (iv) complexity in the distribution and abundance of CSαβ subgroup members; and (v) that putative AMPs are expressed in host-facing life stages and biofluids of key nematode parasites. These data indicate that phylum Nematoda displays diversity in putative AMPs and underscores the need for functional characterisation to reveal their role and importance to nematode biology and host-nematode-microbiome interactions.
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Malyutina. "ABOUT EFFECTS OF SOME NEUROPEPTIDES ON LOCOMOTOR BEHAVIOR OF CYST-FORMING PLANT NEMATODES." THEORY AND PRACTICE OF PARASITIC DISEASE CONTROL, no. 21 (May 29, 2020): 213–16. http://dx.doi.org/10.31016/978-5-9902341-5-4.2020.21.213-216.
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The article presents an analysis of world literature on the study of the physiological and functional significance of FMRFamide-like neuropeptides in the neurobiology of cyst-forming plant parasitic nematodes (by the example of larvae of the 2-yearold potato cyst nematode Globodera pallida and G. rostochiensis, and soybean cyst nematode Heterodera glycines). It was shown that the basic physiological and functional characteristics of FMRFamide-like neuropeptides were obtained from the effects that have some neuropeptides on the motor activity of intact nematode larvae, and molecular studies of flp-genes that encode FMRFamidelike neuropeptides. FMRFamide-like neuropeptides belong to the largest and most diverse family of signal neuropeptides found in invertebrate animals including numerous representatives of the Nematoda type which can significantly modulate the locomotor behavioral reactions of these animals. The work discusses a physiological function of FMRFamide-like neuropeptides and the identified putative receptor of one of the neuropeptides in locomotor behavioral reactions that ensure the vital activity of cyst-forming nematodes, and the possibility of using the data in developing new targeted anthelmintics. The fact of revealing the peptidergic nervous system in cyst-forming plant nematodes, parasitic nematodes of vertebrate animals and freeliving nematodes confirms the concept about the conservation of the peptidergic nervous system in representatives of the entire Nematoda type in general.
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Ramdani, Souhila, Jean-Paul Trilles, and Zouhir Ramdane. "Histopathological changes from parasitic Nematoda infestation in the musculature of some marine teleost fishes from the Algerian coast." Fisheries & Aquatic Life 30, no. 4 (December 1, 2022): 209–16. http://dx.doi.org/10.2478/aopf-2022-0020.
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Abstract Numerous marine fishes from the Algerian coast were examined for nematode parasites. Our study revealed five species of nematodes that were identified according to morphological characteristics: Anisakis simplex, Hysterothylacium aduncum, Hysterothylacium reliquens, Hysterothylacium fabri, Dichelyne pleuronectidis. D. pleuronectidis was newly collected from the study region. Four new host species were recorded for A. simplex, six for H. aduncum, and three for H. fabri. The infection rates observed were higher for Hysterothylacium and Dichelyne than Anisakis. The highest infection rate by Nematoda parasites were recorded for Trachinus draco L., Pagellus acarne (Risso) and Mullus barbatus L. (P = 100%, P = 53.33%, P = 42.5%), respectively. Nematoda larvae were found in body cavity and musculature. Histological changes associated with nematode musculature infestation revealed myodegeneration of fibers with a loss of striated texture and skin damage.
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DJIWANTI, SETYOWATI RETNO, and SUPRIADI SUPRIADI. "EKOBIOLOGI NEMATODA HAWAR DAUN (Aphelenchoides fragariae) PADA TANAMAN SAMBILOTO (Andrographis paniculata)." Jurnal Penelitian Tanaman Industri 17, no. 3 (June 19, 2020): 95. http://dx.doi.org/10.21082/jlittri.v17n3.2011.95-101.
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<p>ABSTRAK</p><p>Nematoda hawar daun (Aphelenchoides fragariae) merupakan salahsatu kendala dalam budidaya tanaman obat sambiloto (Andrographispaniculata). Informasi tentang perilaku dan cara pengendalian nematodapada tanaman sambiloto masih sangat terbatas. Dalam rangka mencari carapengendalian nematoda yang efektif, maka penelitian ini bertujuan untukmengetahui ekobiologi nematoda tersebut seperti kisaran inang, sumberinokulum, dan pestisida. Penelitian dilakukan di laboratorium, rumah kaca,dan kebun percobaan Balittro pada tahun 2006-2008. Studi kisaran inangalami dilakukan dengan mengamati karakteristik gejala khas penyakit,ekstraksi, dan karakterisasi morfologi nematoda dari sampel daun-daungulma yang tumbuh di pembibitan dan pertanaman sambiloto. Studi sum-ber penularan nematoda dilakukan dengan metode bioassay, yaitu denganmengamati gejala hawar daun dan jenis nematoda pada bibit sambilotoyang ditanam pada beberapa macam media tumbuh (tanah steril dicampurdengan beberapa macam jenis bahan organik seperti pupuk kandang,kompos, pupuk organik, dan potongan daun-daun sambiloto sakit).Sedangkan studi sensitivitas nematoda terhadap pestisida sintetik dannabati dilakukan di rumah kaca dan di lapang. Hasil penelitian menun-jukkan bahwa 6 jenis gulma, yaitu babadotan (Ageratum conyzoides),pulus hayam (Acalypha lanceolata), calincing (Oxalys sepium), gulmaBorreria sp., gulma daun sirih (Lindernia sp.), dan paku (Pleocnemia sp.)merupakan inang pengganti nematoda A. fragariae. Bahan organik sepertipupuk kandang dan serasah daun sambiloto sakit dalam tanah merupakansumber penting inokulum A. fragariae, tetapi penyebaran utama penyakitterjadi melalui bibit terinfeksi dan kontak fisik antara daun sakit dengandaun sehat. Perkembangan penyakit hawar daun berlangsung selama 2-4minggu setelah infeksi pertama. Senyawa karbofuran (2-5 g/tanaman),CNSL (cashew nut shell liquid) (0,5-1,0%), tepung (10,0-15,0 g/tanaman),dan ekstrak biji mimba (0,5-1,0%) efektif menekan populasi A. fragariae.Penanaman bibit sehat, sanitasi kebun, penggunaan pupuk kandang yangbenar-benar matang, dan aplikasi pestisida merupakan faktor pentingdalam pengendalian penyakit hawar daun nematoda pada sambiloto.</p><p>Kata kunci: Andrographis paniculata, sambiloto, nematoda hawar daun,Aphelenchoides fragariae, ekobiologi</p><p>ABSTRACT</p><p>Bioecology of Leaf Blotch Nematode (Aphelenchoidesfragariae) on King of Bitter Plant (Andrographispaniculata)</p><p>Leaf blotch nematode (Aphelenchoides fragariae) is one of the mostimportant constrains on cultivation of king of bitter plant (Andrographispaniculata). Information on the bioecology and control method of thenematode is still limited. In relation to finding an effective control methodof the nematode, this study aimed to evaluate several bioecological factorsof the nematode, such as its host range, inoculums source, and sensitivityof the nematode to several chemicals. The studies were conducted inlaboratory, green house, and experimental station of the IndonesianMedicinal and Aromatic Crops Research Institute in 2006-2008. Naturalhost range of the nematode was studied by examining the typical diseasesymptoms on leaves of several weeds grown in the nursery and field of theking of bitter plants, followed with extraction and morphologicalexamination of nematodes. Infection source of the nematode was carriedout by bioassay method using healthy king of bitter seedlings grown onsoil planting medium incorporated with suspected infection sources suchas animal manure, compost, organic fertilizer, and diseased leaf cutting ofthe plants. Sensitivity of the nematode to several pesticides (carbofuran,neem seed powder, neem seed extract, and cashew nut shell liquid) wasconducted in the green house and field. The results showed that six weedssuch as Ageratum conyzoides, Acalypha lanceolata, Oxalys sepium,Borreria sp., Lindernia sp., and Pleocnemia sp. grown in the nursery andfield of king of bitter plantation were infected with the nematode; thereforethese plants are natural alternate hosts of A. fragariae. Organic animalmanure and infected fallen leaves of the king of bitter were importantsources of inoculums of A. fragariae, however, main spread of the diseasewas through infected seedlings and direct contact between healthy andinfected leaves. Leaf blotch disease development occurred 2-4 weeks afterfirst infection. Chemicals such as carbofuran (2-5 g/plant), cashew nutshell liquid (0.5-1.0%), neem seed powder (10.0-15.0 g/plant) and extract(0.5-1.0%) were effectively suppressed the nematode. Planting disease-free seedlings, sanitation, and application of well-decomposed animalmanure and certain chemical pesticides are important factors to control theleaf blotch nematode on king of bitter plant.</p><p>Key words: Andrographis paniculata, king of bitter, leaf blotchnematode, Aphelenchoides fragariae, bioecology.</p>
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HARNI, RITA, SUPRAMANA SUPRAMANA, MEITY S. SINAGA, GIYANTO GIYANTO, and SUPRIADI SUPRIADI. "PENGARUH FILTRAT BAKTERI ENDOFIT TERHADAP MORTALITAS, PENETASAN TELUR DAN POPULASI NEMATODA PELUKA AKAR Pratylenchus brachyurus PADA NILAM." Jurnal Penelitian Tanaman Industri 16, no. 1 (June 19, 2020): 43. http://dx.doi.org/10.21082/jlittri.v16n1.2010.43-47.
Full textAbstract:
<p>ABSTRAK</p><p>Pratylenchus brachyurus merupakan salah satu patogen utama padatanaman nilam di Indonesia. Pengendalian yang banyak dilakukan petanisaat ini adalah menggunakan pestisida sintetik. Penggunaan pestisidasintetik yang terus menerus merupakan ancaman terhadap lingkungan, dankesehatan manusia. Bakteri endofit mungkin dapat dimanfaatkan sebagaisalah satu teknik pengendalian nematoda yang ramah lingkungan karenabakteri endofit dapat menghasilkan racun yang toksik terhadap nematoda.Tujuan penelitian adalah melihat pengaruh kultur filtrat bakteri endofitterhadap mortalitas nematoda, penetasan telur dan perkembangannematoda di dalam akar nilam. Penelitian dilakukan di Laboratorium danRumah kaca Hama dan Penyakit Balai Penelitian Tanaman Obat danAromatik Bogor, dari bulan Januari sampai April 2008 menggunakanrancangan acak lengkap (RAL). Filtrat bakteri dibuat dengan caramenumbuhkan bakteri endofit pada media TSB selama 48 jam, kemudiandisentrifugasi dengan kecepatan 7.000 rpm selama 15 menit. Filtratdisaring dengan milipore berdiameter 0,22 µm, selanjutnya filtrat diujipada nematoda in vitro dan rumah kaca. Hasil penelitian menunjukkanbahwa filtrat dapat membunuh nematoda dalam waktu 24 jam dengannilai LC 50 sebesar 7,709%. Bakteri endofit isolat TT2 dan EH11memperlihatkan daya bunuh paling tinggi yaitu 91-100%. Di samping itufiltrat bakteri endofit juga dapat menekan penetasan telur nematoda 48,5-74,6% dibanding dengan kontrol. Namun hanya filtrat bakteri endofitisolat EH11 yang nyata dapat menekan populasi nematoda di dalam akarnilam dengan tingkat penekanan sebesar 81,3%.</p><p>Kata kunci : Pratylenchus brachyurus, bakteri endofit, kultur filtrat,Pogostemon cablin</p><p>ABSTRACT</p><p>Effect of culture filtrates endophytic bacteria on themortality, hatching eggs and population of root lesionnematodes Pratylenchus brachyurus on patchouli</p><p>Root lesion nematode (Pratylenchus brachyurus) is an importantpathogen of patchouli in Indonesia and causes significant losses. Controlsystem that are done today is using synthetic pesticides. The use ofsynthetic pesticides is a continuing threat to the environment and humanhealth. However, endophytic bacterial culture filtrates may be used as oneof the nematode control that is environmentally friendly. Effect of culturefiltrates endophytic bacteria on the mortality, hatching eggs and populationroot lesion nematodes Pratylenchus brachyurus on patchouli has beendone in vitro and greenhouse. The results showed that the culture filtrate ofendophytic bacteria produced metabolite toxic to nematodes and wereable to kill P. brachyurus 100% within 24 hours with LC 50 7.709%. TT2and EH11 isolates showed high killing power of 91-100%. The culturefiltrates also inhibited hatching of P. brachyurus eggs compared withcontrols. Not all culture filtrates can suppress the nematode population inthe roots of patchouli. EH11 isolates filtrate really pressing nematodepopulations compared to other isolates.</p><p>Key words: Pratylenchus brachyurus, culture filtrate, endophyticbacteria, Pogostemon cablin</p>
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Mariyono, Mariyono, Eko Yuliarsha Sidhi, and Nugraheni Hadiyanti. "Keefektifan Patogenesitas Steirmema Carpocapsae (all strain) terhadap Hama Plutella xylostella L." Jurnal Agrinika : Jurnal Agroteknologi dan Agribisnis 5, no. 1 (March 29, 2021): 51. http://dx.doi.org/10.30737/agrinika.v5i1.1555.
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The utilization of entomopathogenic nematodes is an example of the uses of an environmentally friendly biological agent. Entomopathogenic nematodes of the family Steinernematidae and Hetrorhabditidae are very potential to control insect pests. The purpose of this study was to study the pathogenicity of the entomopathogenic nematode Steinernema carpocapsae (all strains) as a biological control against Plutella xylostella. This research includes 2 stages, namely the preparation stage and laboratory experiments. The experimental design in this study was a completely randomized design (CRD) consisting of six treatments and three replications. The treatments tested were entomopathogenic nematode concentrations consisting of six levels: 0, 8, 16, 32, 64 and 128 infective juvenile per ml. The LC50 and LT50 values were calculated using Probit analysis. The results of observations of nematodes that enter the insect body and pest mortality were analyzed using analysis of variance (ANOVA), once showing a significant difference, it was then continued to the DMRT test at 5% level. Based on the results of the study, the highest pathogenicity against Plutella xylostella was Steinernema carpocapsae (all strains) when compared to Steinernema glaseri (NC) and Steinernema sp. local isolates. Resistance to Steinernema carpocapsae (all strains) and the LC50 value were determined by the age of Plutella xylostella larvae. The bigger and older the larvae, the more its resistance to Steinernema carpocapsae (All strains) and the LC50 value. The number of entomopathogenic nematodes that enter the body of Plutella xylostella increased with increasing length of contact time.Penggunaan nematoda entomopatogen merupakan salah satu pemanfaatan agensia hayati yang ramah lingkungan. Nematoda entomopatogen dari famili Steinernematidae dan Hetrorhabditidae sangat potensial untuk mengendalikan serangga hama. Tujuan dari penelitian ini adalah mempelajari patogenisitas nematoda entomopatogen Steinernema carpocapsae (all strain) sebagai pengendali hayati terhadap hama Plutella xylostella. Penelitian ini meliputi 2 tahap yaitu tahap persiapan dan percobaan laboratorium. Rancangan percobaan pada penelitian ini adalah Rancangan Acak Lengkap (RAL) yang terdiri enam perlakuan dan tiga ulangan. Perlakuan yang diujikan adalah konsentrasi nematoda entomopatogen yang terdiri enam taraf: 0, 8, 16, 32, 64 dan 128 infektif juvenile/ml. Nilai LC50 dan LT50 dihitung menggunakan analisis probit. Hasil pengamatan nematoda yang masuk dalam tubuh serangga dan mortalitas hama dianalisis menggunakan analisis sidik ragam (ANOVA), apabila menunjukkan beda nyata dilanjutkan uji DMRT taraf 5%. Berdasarkan hasil penelitian, patogenisitas tertinggi terhadap Plutella xylostella adalah Steinernema carpocapsae (all strain) bila dibandingkan dengan Steinernema glaseri (NC) dan Steinernema sp. isolat lokal. Ketahanan terhadap Steinernema carpocapsae (All strain) dan nilai LC50 ditentukan umur larva Plutella xylostella. Semakin besar dan tua umur larva, ketahanan terhadap Steinernema carpocapsae (All strain) dan nilai LC50 juga semakin meningkat. Jumlah nematoda entomopatogen yang masuk kedalam tubuh Plutella xylostella semakin banyak seiring dengan bertambah lamanya waktu kontak.
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Sánchez-Monge, Alcides, and Jorge Cortés. "Marine nematodes of Costa Rica: state of the art." Neotropical Biology and Conservation 19, no. 2 (June 28, 2024): 269–81. http://dx.doi.org/10.3897/neotropical.19.e115345.
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Nematoda is the fourth most diverse animal phylum and is widely distributed. Marine nematodes are generally the most speciose group of meiofauna, yet there are relatively few studies on the taxonomy and biodiversity of free living marine nematodes. Here we present a review of the existing scientific literature and data in international databases on marine nematodes of Costa Rica. Most of the papers currently available mentioned Nematoda as the most abundant phylum in terms of the number of individuals within sand samples, nonetheless, only three publications included taxonomic data such as the description of new species or new records. Most publications are for the Pacific coast and we found only one paper for the Caribbean coast of Costa Rica. Large sections of the coasts and almost all the Exclusive Economic Zone remain unexplored in terms of nematode diversity, abundance and ecological role. Ten species, five free-living and five parasitic species, have been reported from the coasts of Costa Rica. Several reports indicate the presence of nematodes without further identification. More effort should be dedicated to the taxonomic identification of nematodes since, in addition to being the most abundant group, they can also be used as biological indicators.
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Gdemakarti, Yoshua, Bainah Sari Dewi, I. Gede Swibawa, and Irwan Sukri Banuwa. "KOMUNITAS NEMATODA TANAH DI BLOK LINDUNG HUTAN PENDIDIKAN KONSERVASI TERPADU TAMAN HUTAN RAYA WAN ABDUL RACHMAN." Jurnal Hutan Tropis 9, no. 1 (April 18, 2021): 13. http://dx.doi.org/10.20527/jht.v9i1.10464.
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Hutan Pendidikan Konservasi Terpadu (HPKT) is part of Taman Hutan Raya Wan Abdul Rachman (Tahura WAR) enabled to support educational activities and research. The quality of the soil in this area is influenced by several factors, one of the factors i.e. nematodes. The aim of study to know the community of nematodes on the Protection Block, Hutan Pendidikan Konservasi Terpadu, Wan Abdul Rachman Forest Park. The research was conducted in April to May 2018. The soil samples were taken on arboretum seven, arboretum eight, arboretum nine and arboretum 10. Nematode observations were conducted in the laboratory of Plant Pests, Faculty of Agriculture, University of Lampung. Nematodes have been identified to genus level based on morphological traits. The result of study showed that there are 29 genus of nematode consists of 17 plant parasitic nematode genera, seven nematoda bacterial-feeding, three nematode fungal-feeding, one omnivore nematode and one predator nematode. The dominant nematode genera are Criconomella, Helycotylenchulus dan Rotylenchulus. The abundance of nematodes ranges from 251-613 individuals / 300cc soil. The diversity of soil nematodes based on the Shannon-Wienner index ranges from 2.33-2.62. The Shannon-Whienner Index criteria are classified as moderate. The Simpson Index ranges from 0.862-0.907. The highest similarity index genus in arboretum seven with arboretum nine and arboretum eight with arboretum nine with a value of 0.81. The lowest in arboretum seven and arboretum 10 that is 0.63.
Dissertations / Theses on the topic "Nematoda"
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Valadas, Vera Mónica Piegas. "Genetic diversity of entomopathogenic nematodes (Nematoda: Steinernematidae and Heterorhabditidae) and the nematode Bursaphelenchus xylophilus (Nematoda: Aphelenchoididae) from continental Portugal." Doctoral thesis, Universidade de Évora, 2012. http://hdl.handle.net/10174/15718.
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“Diversidade genética dos nemátodes entomopatogénicos
(Nematoda: Steinernematidae e Heterorhabditidae) e do
nemátode Bursaphelenchus xylophilus (Nematoda:
Aphelenchoididade) em Portugal continental”
Os nematodes entomopatogénicos são utilizados como agentes de controlo
biológico. Para compreender a sua diversidade, foi realizada uma prospecção
em Portugal. Cinco espécies, nomeadamente Steinernema feltiae, S.
intermedium, S. kraussei, Steinernema sp. e Heterorhabditis bacteriophora
foram identificadas. As sequências de ITS, região D2D3 do 28S rRNA, COXI e
cytb foram utilizadas para estudar a diversidade genética das duas espécies
mais abundantes, S. feltiae and H. bacteriophora, não tendo sido encontradas
diferenças significativas entre isolados.
O nemátode da madeira do pinheiro, Bursaphelenchus xylophilus, provoca
doença nos pinheiros tendo sido detectada pela primeira vez na Europa e em
Portugal em 1999. Para avaliar a diversidade genética dos isolados
Portugueses e identificar o padrão de propagação da doença, foram utilizadas
a sequência da região IGS do 5.8S rRNA, e os genes cytb e cellulase,
combinados com os padrões ISSR. Os padrões de ISSR mostraram elevada
diversidade genética entre os recentes isolados Portugueses, sugerindo a
possibilidade de uma nova introdução. As árvores filogenéticas dos genes da
celulase e cytb sugeriram uma origem Asiática para os isolados Portugueses; ABSTRACT: Entomopathogenic nematodes are used as biocontrol agents. To understand
their diversity, a survey was undertaken in Portugal. Five species, namely
Steinernema feltiae, S. intermedium, S. kraussei, Steinernema sp. and
Heterorhabditis bacteriophora were identified. The ITS, 28S rRNA D2D3 region,
COXI and cytb sequences, used to study the genetic diversity of the two most
abundant species, S. feltiae and H. bacteriophora, showed no significant
differences among the isolates.
Bursaphelenchus xylophilus causes severe disease in pine trees and was
detected for the first time in Europe and in Portugal in 1999. To evaluate the
genetic diversity of Portuguese isolates and identify disease spread pathways,
the sequence of 5.8S rRNA IGS region, cytb and cellulase genes, combined
with ISSR fingerprints were used. ISSR fingerprints show a high genetic
variability among recent Portuguese isolates, suggesting the possibility of a new
introduction. Phylogenetic trees based on cellulase and cytb genes suggests an
Asian origin for Portuguese isolates.
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Kruitbos, Laura Marina. "Influence of habitat on the behaviour of entomopathogenic nematodes." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=25963.
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Zervos, S. "Population regulation of thelastomatid nematodes (Nematoda: Thelastomatidae) of cockroaches." Thesis, University of Canterbury. Zoology, 1986. http://hdl.handle.net/10092/4791.
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Populations of thelastomatid nematodes in cockroach hosts were
investigated.
The population biology, life history, habits. distribution, and
gross morphology of cockroaches involved are discussed.
New species of thelastomatid nematodes from cockroaches are
described and keys to species of Protrellus and Blatticola are given.
Evidence for population regulation in six species of
thelastomatids in eight species of cockroaches collected from the field
is presented. No host contained two adult males, infrapopulations with
two juvenile males were very rare, the number of adult females per host
was small. and monogamy was common. Juvenile males were rare while
juvenile females were relatively common, indicating that, compared to
females, males develop and are eliminated rapidly from hosts (leaving
one), or that males are less common to start with. Infection prevalence
varied markedly between the cockroach species.
Reproductive competition due to crowding, and cyclical egg
production were found in two species.
these phenomena are discussed.
Mechanisms which may control
The effects of density-independent climatic factors on seasonal
variation in incidence and infrapopulation structure of one thelastomatid
population were transient.
Evidence for population self-regulation in Protrellus dixoni
was obtained from laboratory studies. Infrapopulations were regulated
by a density-dependent and sex-dependent reduction in infection intensity
with infrapopulation age. This reduction was not equal in initial speed
or intensity between the sexes (reduction in number of males was faster)
and led to infrapopulations with never more than a single adult male. and
few adult females. In structure. these laboratory-produced infrapopulations
resembled those in field collected hosts.
Unmated females produced male progeny only (probably by
arrhenotokous parthenogenesis). Female offspring probably result
from amphimixis.
Possible methods of thelastomatid infrapopulation regulation are
discussed. It is concluded that regulation is parasite-mediated and due
to chemical interference competition. Regulation benefits the surviving
nematodes because per capita fecundity is greater in uncrowded infrapopulations.
Self-regulation may be common among thelastomatids and
other parasites.
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Cho, Hyun-Bae. "Molecular characterization and phylogenetics of entomopathogenic nematodes (nematoda: stienernematidae) from Asia." Thesis, The University of Arizona, 2009. http://hdl.handle.net/10150/192304.
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Yu, Hao. "Parasitism of Subterranean Termites (Isoptera: Rhinotermitidae: Termitidae) by Entomopathogenic Nematodes (Nematoda: Steinernematidae: Heterorhabditidae)." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/195263.
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The biological control of subterranean termites (Isoptera: Rhinotermitidae; Termitidae) using entomopathogenic nematodes (Nematoda: Steinernematidae; Heterorhabditidae) (EPN) was investigated. The desert subterranean termite Heterotermes aureus Snyder was found to be very susceptible to Steinernema riobrave Cabanillas, Poinar and Raulston. In laboratory bioassays S. riobrave (355, TP, 3-8b and 7-12 strains), S. carpocapsae Weiser (Mexican 33 strain), S. feltiae Filipjev (UK76 strain), and Heterorhabditis bacteriophora Poinar (HP88 strain) were all capable of infecting and killing H. aureus, Reticulitermes flavipes Kollar, R. virginicus Banks, Coptotermes formosanus Shiraki and Gnathamitermes perplexus Banks. In sand assays, S. riobrave caused > 90% H. aureus mortality in 3 days and 100% mortality by day 5 at 22 °C. TP strain of S. riobrave caused 75% R. flavipes mortality and 90.91% C. formosanus mortality in 7 days. EPNs utilizing termites as hosts produced smaller sized offspring, with the exception of S. feltiae. Stunted females of S. feltiae were frequently found in termite cadavers, but no progeny. Small IJs of S. carpocapsae, S. riobrave and H. bacteriophora infect, reproduce and form normal size IJs after subsequent infection in Galleria mellonella L. The progeny of small IJs were as effective as the normal size IJs, with regard to subsequent induced mortality, under the conditions tested. In laboratory two-container choice experiments, H. aureus were repelled by EPN treated areas for up to 10 days at 10,000 IJs per device. The repellency threshold was found to vary among nematodes species. We hypothesis that it is the physical movement of the nematodes that repels the termites. Temperature is a key factor affecting nematode pathogenicity. Temperature tolerance of the nematodes varied between species. After a gradual heat adaptation process, S. riobrave and H. bacteriophora caused significantly higher H. aureus mortality at 32 °C compared with original laboratory cultured strains. Further work may result in the contribution of commercially available strains with enhanced heat tolerance. Preliminary field studies confirmed EPN protection of a structure, however, termites began to reinfest 4 weeks after the application. Additional tests are necessary to provide more evidence before we can conclude nematodes as useful in the field.
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Ratnasinghe, Gamini. "Biological control of diamondback moth, Plutella xylostella (Lepidoptera: yponomeutidae) with entomopathogenic nematodes (Nematoda: rhabditida)." Thesis, University of Reading, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308035.
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LASSERRE, FRANCOISE. "Lutte integree contre heterodera avenae (nematoda) : consequences sur une communaute de nematodes en ecosysteme cerealier." Rennes 1, 1994. http://www.theses.fr/1994REN10053.
Full textAbstract:
L'objet de cette etude etait de proposer un modele de gestion integree des populations de nematodes en agroecosysteme cerealier. Six itineraires de lutte bases sur une rotation de type mais-ble-ble, differant par le degre de couverture chimique par un nematicide et par l'introduction ou non d'une variete resistante en premier ble, ont ete compares selon des criteres economiques et ecologiques. La variete resistante a permis un gain de 10% sur le deuxieme ble; par contre, la protection chimique du mais s'est averee d'efficacite tres dependante des conditions climatiques. Par ailleurs, l'etude a considere les effets a long terme de la culture repetee de l'avoine panema resistante a h. Avenae. La chute subsequente de ce nematode entraine une multiplication des effectifs de pratylenchus neglectus, nematode des lesions necrotiques, a des effectifs nuisibles sur ble d'hiver; elle cause egalement une chute durable de l'inoculum du champignon endoparasite verticillium chlamydosporium dont l'absence favorise les remontees foudroyantes des populations d'h. Avenae des que des cultures hotes succedent a la variete resistante. L'application repetee du meme gene de resistance a egalement selectionne un pathotype virulent sur l'avoine panema. Les structures genetiques de ce dernier (polymorphisme enzymatique) se sont averees significativement differentes de celles de la population d'origine. Il est important de tenir compte de tels risques dans une strategie d'utilisation optimale de la resistance, elle-meme faisant partie d'un programme de gestion integree des populations de nematodes
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Mezzalira, Itamara. "Análise funcional de proteínas efetoras de Meloidogyne incognita com potencial aplicação no controle de fitonematoides." reponame:Repositório Institucional da UnB, 2013. http://repositorio.unb.br/handle/10482/13841.
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Dissertação (mestrado)—Universidade de Brasília, Instituto de Ciências Biológicas, Departamento de Biologia Celular, Programa de Pós-Graduação em Biologia Molecular, 2013.Submitted by Luiza Silva Almeida (luizaalmeida@bce.unb.br) on 2013-07-30T20:15:42Z No. of bitstreams: 1 2013_ItamaraMezzalira.pdf: 1833540 bytes, checksum: 37510b82177c627dc73b548a5947cd12 (MD5)
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Nematoides formadores de galhas (NFG) (Meloidogyne spp.) são endoparasitas biotróficos que possuem uma ampla gama de hospedeiros. O sucesso do parasitismo dos NFG depende da indução e manutenção de sítios de alimentação altamente especializados que são compostos por células gigantes. Os NFG produzem uma série de proteínas nas glândulas secretoras e as injetam, via estilete, nas células da planta hospedeira para manipular o seu metabolismo. Elucidar o papel das proteínas secretadas é essencial para o entendimento das bases moleculares do processo de parasitismo dos nematoides, bem como para o desenvolvimento de novas estratégias para o controle destes parasitas. Este trabalho é o início de uma análise detalhada sobre o papel que três proteínas efetoras de M. incognita, MSP2, MSP7 e MSP18, desempenham na interação com arroz (Oryza sativa). Os genes de parasitismo de M. incognita MSP2, MSP7 e MSP18 codificam para proteínas de 210, 176 e 172 aminoácidos, respectivamente, são expressos nas glândulas secretoras do nematoide e possuem peptídeo sinal de secreção na extremidade N-terminal. A análise de expressão através de qRT-PCR mostrou que estes genes apresentam diferentes padrões de expressão durante interação planta-nematoide, sendo que MSP2 tem seu pico de expressão na fase inicial de estabelecimento do parasitismo, enquanto MSP7 e MSP18 são expressos ao longo de todo o ciclo de parasitismo. Resultados de experimentos de transformação transiente de células da epiderme de cebola, via biobalística, mostraram que o produto da fusão MSP2-EGFP apresentou forte sinal de fluorescência no núcleo, enquanto que os produtos das fusões MSP7-EGFP e MSP18-EGFP mostraram sinal de fluorescência no citoplasma e no núcleo da célula vegetal. Estes resultados mostram que estas proteínas são direcionadas a diferentes compartimentos subcelulares da célula vegetal. Foram obtidas plantas transgênicas de arroz (O. sativa cv. Nipponbare) expressando as proteínas MSP2, MSP7 e MSP18, sem o peptídeo sinal de secreção, e micro-RNAs artificiais (amiRNAs) capazes de silenciar a expressão dos genes corespondentes no nematoide. Para cada gene estudado, dois amiRNAS foram selecionados. Para cada construção uma média de 24 plantas transgênicas foram obtidas. Análises de Southern-blot and qPCR foram realizadas para identificar plantas T0 com apenas uma cópia do transgene e para cada construção foram selecionadas três linhagens T1 para avanço de geração e, posterior, realização de bioensaios. A análise do processo de infecção das plantas transgênicas por M. incognita irá permitir a identificação de genes essenciais para o estabelecimento do parasitismo. Os dados obtidos nestas análises irão ampliar o conhecimento sobre as proteínas efetoras de fitonematoides e trazer novas possibilidades para o desenvolvimento de estratégias de controle de Meloidogyne spp. em arroz e outras culturas de interesse. _______________________________________________________________________________________ ABSTRACT
Root-knot nematodes (RKN) (Meloidogyne spp.) are endo-parasites with a wide host range. Effector proteins, produced in the nematode esophageal gland cells and released in the host plant cells through stylet, dramatically modify selected plant cells into giant-cells, which are the permanent food source to the sedentary nematode. Elucidating the role of different nematode effectors is essential to understanding the molecular basis of nematode parasitism as well as to developing new nematode control strategies. This study is the beginning of an extensive analysis to assess the functional role of three M. incognita effector proteins, MSP2, MSP7 and MSP18, during rice-nematode interaction. The coding sequence of MSP2, MSP7 and MSP18 encoded proteins with 210, 176 e 172 amino acids, respectively, including N-terminal signal peptides. These genes are expressed exclusively in the nematode esophageal gland cells. qPCR analysis of transcript accumulation showed that MSP2, MSP7 and MSP18 genes displayed different expression patterns during host infection. MSP2 reaches the maximum expression level in the beginning of parasitism cycle. MSP7 and MSP18 are highly expressed during the whole parasitism cycle. To test the localization of MSP2, MSP7 and MSP18 in plant cells, a protein transient expression assay was performed. The fusion product of MSP2-GFP showed a strong fluorescence signal in plant nuclei, while the fluorescence signal of the MSP7-GFP and MSP18-GFP fusion products were observed in plant cytoplasm and nuclei. Reverse and forward genetic analyses were conducted to assess the role of the candidate proteins in plant-nematode interactions. We used rice (Oryza sativa cv. Nipponbare) to generate transgenic plants expressing MSP2, MSP7 and MSP18 full-length cDNAs or artificial micro-RNAs (amiRNAs) able to silence the cognate genes in the nematode. For each gene studied, two amiRNAs were selected to perfectly match the M. incognita candidate gene but not other nematode or plant sequences. For each construct, an average of 24 plants was recovered. Southern- blots and qPCR analyses identified single-copy gene (or amiRNA) constructs insertion in the genome of the transformed plants (T0 plants). Assessment of nematode growth and development on transgenic plants will allow selecting genes involved in establishing the compatibility with the host plant. Data obtained should significantly widen our knowledge of molecular players contributing to nematode pathogenicity, opening new avenues for Meloidogyne spp. control strategies in rice and other crops of interest which are highly susceptible to M. incognita.
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Estevez, Annette Orene Zager. "The role of the daf-8 gene in Caenorhabditis elegans dauer larva development /." free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9841284.
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Lau, Ching-man Tracy. "Study of specific genes in trichinella spiralis (nematoda) by differential display /." Hong Kong : University of Hong Kong, 1999. http://sunzi.lib.hku.hk/hkuto/record.jsp?B20979009.
Full textBooks on the topic "Nematoda"
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Nesterov, P. I. Klass kruglykh cherveĭ--nematoda: Sistematika, ėkologii͡a︡, zoogeografii͡a︡ i prakticheskoe znachenie nematod. Kishinev: "Shtiint͡s︡a", 1988.
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2
Wharton, David A. A functional biology of nematodes. London: Croom Helm, 1986.
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Wharton, David A. A functional biology of nematodes. Baltimore, Md: Johns Hopkins University Press, 1986.
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Gagarin, V. G. Svobodnozhivushchie nematody presnykh vod Rossii i sopredelʹnykh stran: Fauna i puti ee formirovanii͡a︡, ėkologii͡a︡, taksonomii͡a︡, filogenii͡a︡. Moskva: "Nauka", 2001.
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Lemzina, L. V. Svobodnozhivushchie nematody ozer Issyk-Kulʹ i Son-Kulʹ. Frunze: "Ilim", 1989.
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Randy, Gaugler, ed. Entomopathogenic nematology. New York: CABI Pub., 2002.
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Andrássy, I. Free-living nematodes of Hungary: Nematoda errantia. Budapest: Hungarian Natural History Museum, 2005.
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Rubt͡sov, I. A. Fresh-water mermithids of Estonia. New Delhi: Oxonian Press, 1988.
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Platonova, T. A. Nematodes and their role in the meiobenthos. New Delhi: Oxonian Press, 1985.
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Skarbilovich, T. S. Bibliography of Russian literature on nematodes: Published between 1874 and 1975 = Otechestvennaya literatura po nematodam rastenii, nasekomykh, pochvy i vodnoi sredy, za period s 1874 po 1975 gg : bibliografiya. New Delhi: Oxonian Press, 1985.
Find full textBook chapters on the topic "Nematoda"
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Specht, Sabine, and Achim Hoerauf. "Nematoda: Filarial Nematodes." In Immunity to Parasitic Infection, 217–30. Chichester, UK: John Wiley & Sons, Ltd, 2012. http://dx.doi.org/10.1002/9781118393321.ch11.
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Cole, Theodor C. H. "VI. Nematoda – Fadenwürmer – Nematodes." In Wörterbuch der Wirbellosen / Dictionary of Invertebrates, 39–44. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-662-52869-3_6.
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Sommer, Ralf J. "Nematoda." In Evolutionary Developmental Biology of Invertebrates 3, 15–33. Vienna: Springer Vienna, 2015. http://dx.doi.org/10.1007/978-3-7091-1865-8_2.
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Loos-Frank, Brigitte, and Sabine Begall. "Nematoda." In Zoologica Poetica, 21–27. Berlin, Heidelberg: Springer Berlin Heidelberg, 2020. http://dx.doi.org/10.1007/978-3-662-61568-3_3.
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Despommier, Dickson D., and John W. Karapelou. "Nematoda." In Parasite Life Cycles, 93–123. New York, NY: Springer New York, 1987. http://dx.doi.org/10.1007/978-1-4612-3722-8_4.
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Mitsuhashi, Jun. "Nematoda." In Invertebrate Tissue Culture Methods, 203–7. Tokyo: Springer Japan, 2002. http://dx.doi.org/10.1007/978-4-431-67875-5_17.
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Mitsuhashi, Jun. "Nematoda." In Invertebrate Tissue Culture Methods, 293–94. Tokyo: Springer Japan, 2002. http://dx.doi.org/10.1007/978-4-431-67875-5_27.
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Pandian, T. J. "Nematoda." In Reproduction and Development in Minor Phyla, 83–120. First edition. | Boca Raton : CRC Press, 2021. | Series:: CRC Press, 2021. http://dx.doi.org/10.1201/9781003057512-15.
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Barrios, Roberto, and Abida K. Haque. "Nematoda." In Parasitic Diseases of the Lungs, 69–74. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-37609-2_5.
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Helder, Johannes, and Holger Heuer. "Let's be inclusive - the time of looking at individual plant parasitic nematodes is over, and new technologies allow for it." In Integrated nematode management: state-of-the-art and visions for the future, 403–7. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789247541.0056.
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Abstract Parasitism is a popular life style among members of the phylum Nematoda. Around 46% of the 27,000 described nematode species use either a plant or an animal as a primary food source. Molecular phylogenetics has aided in deciphering patterns of evolution and diversification among plant parasitic nematodes. Alignments comprising over 5000 nearly full-length small subunit ribosomal DNA sequences (each approximately 1700 bp) with a fairly good coverage of all extant nematode families allowed to pinpoint patterns with regard to the appearance of plant parasitism. This chapter describes the soil biome, identification of nematode and microbial community in soil, as well as the activity of microbiome. Future plant parasitic nematode management strategies are also mentioned. Exploring and boosting the soil suppressive potential will be a major additional tool in the foreseeable future.
Conference papers on the topic "Nematoda"
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Malyutina, T. A. "NEUROPEPTIDES INVOLVING IN THE REGULATION OF LOCOMOTOR BEHAVIOR OF ROOT-KNOT PLANT-PARASITIC NEMATODES (REVIEW)." In THEORY AND PRACTICE OF PARASITIC DISEASE CONTROL. All-Russian Scientific Research Institute for Fundamental and Applied Parasitology of Animals and Plant – a branch of the Federal State Budget Scientific Institution “Federal Scientific Centre VIEV”, 2023. http://dx.doi.org/10.31016/978-5-6048555-6-0.2023.24.281-284.
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In the last few decades, the attention of researchers has been attracted by endogenous
FMRFamide-like neuropeptides found in a number of invertebrates, including
species of the Nematoda phylum. A foreign literature review was presented for
the functional significance of endogenous FMRFamide-like neuropeptides in
locomotor behaviour of root-knot phytonematodes, representatives of the genus
Meloidogyne Goldi, 1982, namely, Meloidogyne incognita, M. minor, M. hapla and
M. graminicola. In Russia, such studies are not carried out. The main characteristics
of phytoparasitic neuropeptides were obtained from the study of genes (flp-genes)
that encode these neuropeptides. M. incognita was found to have FMRFamidelike positive immunoreactivity in the central nervous system and 19 flp genes. The
Mi-flp-12 and Mi-flp-14 genes encode neuropeptides that stimulate locomotor
behaviour, while Mi-flp-32 encodes a neuropeptide that inhibits parasite locomotor
behaviour. Nematodes M. incognita and M. hapla were found to have G-proteincoupled receptors (GPCRs) encoded by the flp-32 gene, and their similarity
to receptor 1 (C26F1) of the free-living nematode Caenorhabditis elegans was
detected. Similar data were presented in the literature for M. graminicola. The
peptidergic signaling nervous system of root-knot phytonematodes is similar to the
system of nematodes in vertebrates and free-living nematodes, which indicates the
conservatism of the system in species of the entire Nematoda phylum.
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Khusainov, R. V. "CEPHALOBID NEMATODES (NEMATODA: CEPHALOBIDAE) IN AGROCENOSIS OF THE CENTRAL-EUROPEAN PART OF RUSSIA." In V International Scientific Conference CONCEPTUAL AND APPLIED ASPECTS OF INVERTEBRATE SCIENTIFIC RESEARCH AND BIOLOGICAL EDUCATION. Tomsk State University Press, 2020. http://dx.doi.org/10.17223/978-5-94621-931-0-2020-43.
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Investigations of fauna of cephalobid nematodes from field agrocenosis were carried from the territory of the Central-European part of Russia in 2016–2018. In total ten genera of the family Cephalobidae were found. Nematodes of genus Acrolobus (A. emarginatus) has been reported in Russia for the first time. Chiloplacus and Eucephalobus nematodes were presented by the most species diversity. Nematodes of genera Cephalobus and Eucephalobus founded in the samples constantly (93 & 90% samples respectively). The second by frequency of occurence was taken species from genera Acrobeloides and Chiloplacus (86 & 75% samples). Acrobeles spp. and Cervidellus spp. detected in almost half of the soil samplies (57 & 48%). Acrolobus and Heterocephalobus nematodes were most rarely discovered genus (24 & 16%). Acroucrainicus and Stegelletina nematodes founded in agrocenosis singly and only in the territory of the Chernozem Region. Species of genera Acrolobus and Heterocephalobus were registered into the roots generally, while of the rest cephalobid genera were founded both in soil and into damaged or necrotic roots.
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Kluiters, Georgette. "Nematode parasitism of arbovirus vectors: Effects of mermithids (Nematoda: Mermithidae) onCulicoidesbiting midges and their potential use for disease and vector control." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.109410.
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Awaludin, Aan, Agustinus Gede Nyoman Mariyanto, Nurkholis, Suci Wulandari, Suluh Nusantoro, Nur Muhamad, M. Adhyatma, et al. "Parasit gastrointestinal pada Domba Ekor Gemuk di Kabupaten Jember." In The 2nd National Conference of Applied Animal Science (CAAS) 2021. Politeknik Negeri Jember, 2021. http://dx.doi.org/10.25047/animpro.2021.17.
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Tujuan penelitian adalah untuk mengidentifikasi parasit gastrointestinal yang menginfeksi saluran pencernaan pada Domba Ekor Gemuk di kabupaten Jember. Penelitian ini menggunakan sampel feses segar dari 50 ekor Domba Ekor Gemuk di kabupaten Jember. Pengambilan sampel secara acak dengan tidak membedakan jenis kelamin dan umur Domba Ekor Gemuk. Identifikasi parasit gastrointestinal dengan menggunakan uji apung (flotation methods) kemudian dilakukan pengamatan morfologi telur cacing dan oosista yang ditemukan pada sampel feses Domba Ekor Gemuk. Hasil identifikasi adalah ditemukannya parasit gastrointestinal pada Domba Ekor Gemuk di kabupaten Jember dari kelas nematoda dan protozoa. Parasit cacing kelas nematoda yang teridentifikasi adalah Strongyloides sp., Cooperia sp., Moniezia sp., Capillaria sp., dan Ostertagia sp., sedangkan protozoa yang teridentifikasi adalah Eimeria sp. Prevalensi parasit gastrointestinal didominasi oleh Strongyloides sp. (20%), Eimeria sp. (8%), Moniezia sp. (8%), Capillaria sp. (4%), Cooperia sp. (2%), dan Ostertagia sp. (2%). Kejadian infeksi murni atau infeksi tunggal (single infections) sebanyak 95% dan infeksi campuran (co-infections) sebanyak 5%.
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Lobanova, V. V., B. E. Efimenko, and K. Yu Popadin. "USING BARCODING DATA TO ANALYZE THE MUTAGENESIS OF NEMATODE MITOCHONDRIAL DNA." In OpenBio-2023. ИПЦ НГУ, 2023. http://dx.doi.org/10.25205/978-5-4437-1526-1-25.
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The Nematoda phylum is a promising group for studying the relationship between ecological and genetic characteristics, but the number of high-quality sequences, including mtDNA, is small. In this work, the possibility of increasing the database for these aims by using barcoding data (COX1) was considered, possible problems and their significance for mtDNA mutagenesis analyses were identified.
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Dewi, D. A., E. Martindah, D. H. Sawitri, A. H. Wardhana, and F. Ekawasti. "Deteksi Larva Cacing Nematoda Sebelum dan Sesudah Pengobatan pada Beberapa Bangsa Domba." In Prosiding Seminar Nasional Teknologi Peternakan dan Veteriner. Pusat Penelitian dan Pengembangan Peternakan, 2017. http://dx.doi.org/10.14334/pros.semnas.tpv-2017-p.365-372.
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Loginova, O. A., D. I. Chuprak, and S. B. Rozenfel'd. "ON INDEPENDENT DIAGNOSTIC VALUE OF EGG MEMBRANES OF MARSHALLAGIA SPP. (NEMATODA: STRONGYLIDA)." In Современные проблемы общей и прикладной паразитологии. Воронеж: Цифровая полиграфия, 2022. http://dx.doi.org/10.57007/9785907283979_2022_16_56-61.
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Romashova, N. B., and B. V. Romashov. "ACTUAL RESULTS ON THE DISTRIBUTION OF THE NEMATODE CALODIUM HEPATICUM (NEMATODA, CAPILLARIIDAE) IN MOUSE-LIKE RODENTS IN THE NATURAL CONDITIONS OF THE VORONEZH REGION." In Современные проблемы общей и прикладной паразитологии. Воронеж: Цифровая полиграфия, 2022. http://dx.doi.org/10.57007/9785907283978_2022_16_91-98.
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Van Goor, Justin Michael. "Parasitodiplogaster(Nematoda: Diplogastridae) infection of male fig wasps: Consequences for mutualism and coexistence." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.114703.
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Adiwena, Muh, FNU Mardhiana, Aditya Murtilaksono, Dwi Santoso, Rizza Wijaya, and Ankardiansyah Pandu Pradana. "Seleksi dan Karakterisasi Pertumbuhan Cendawan Tanah Penghasil Enzim Protease Asal Rhizosfer Padi di Tarakan – Kalimantan Utara." In Seminar Nasional Semanis Tani Polije 2020. Politeknik Negeri Jember, 2020. http://dx.doi.org/10.25047/agropross.2020.40.
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Cendawan tanah memegang peran esensial dalam budidaya pertanian berkelanjutan. Kemampuannya dalam memproduksi berbagai senyawa metabolit menjadikan cendawan sebagai salah satu agens hayati yang potensial untuk mengendalikan patogen tanaman. Salah satu metabolit sekunder cendawan yang bersifat anti-patogen adalah enzim ekstraseluler protease. Enzim ini dapat mendegradasi dinding sel cendawan patogen, nematoda, dan telur nematoda. Penelitian ini bertujuan untuk mengisolasi cendawan penghasil enzim protease dari rhizosfer padi dan mengkarakterisasi pertumbuhannya. Sampel tanah diambil dari 5 titik pengambilan sampel pada lahan padi petani di Kelurahan Mamburungan, Kota Tarakan, Kalimantan Utara. Isolasi dilakukan menggunakan media potato dextrose agar (PDA) pada suhu 37°C di Laboratorium Perlindungan Tanaman, Universitas Borneo Tarakan. Cendawan yang tumbuh dikarakterisasi bentuk makroskopisnya secara visual. Pengujian aktivitas proteolitik dilakukan menggunakan media PDA yang ditambah dengan skim milk. Seluruh cendawan yang tumbuh kemudian dikarakterisasi kecepatan tumbuhnya selama 11 hari. Hasil penelitian menunjukkan terdapat 7 isolat cendawan yang berhasil diisolasi, dan 3 (48,85%) diantaranya mampu menghasilkan enzim protease. Isolat yang mampu menghasilkan enzim protease adalah isolat C5, C6, dan C7. Selanjutnya, berdasarkan karakter pertumbuhannya, tujuh isolat yang diperoleh menunjukkan respon yang beragam. Pada hari ke-11, pertumbuhan tertinggi ditunjukkan oleh isolat C1, C2, C5, dan C6 dengan diameter 8,5 cm. Pertumbuhan paling lambat ditunjukkan oleh isolat C7 dengan diameter 2,53 cm. Penelitian ini memberikan informasi bahwa terdapat cendawan proteolitik dari rhizosfer padi pada lokasi penelitian dengan karakter pertumbuhan yang beragam.
Reports on the topic "Nematoda"
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Spiegel, Yitzhak, Michael McClure, Itzhak Kahane, and B. M. Zuckerman. Characterization of the Phytophagous Nematode Surface Coat to Provide New Strategies for Biocontrol. United States Department of Agriculture, November 1995. http://dx.doi.org/10.32747/1995.7613015.bard.
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Chemical composition and biological role of the surface coat (SC) of the root-knot nematodes, Meloidogyne spp. are described. SC proteins of M. incognita race 3 infective juveniles (J2) were characterized by electrophoresis and western blotting of extracts from radioiodine and biotin-labelled nematodes. J2 labelled with radioiodine and biotin released 125I and biotin-labelled molecules into water after 20 hours incubation, indicating that SC proteins may be loosely attached to the nematode. Antiserum to the principal protein reacted with the surface of live J2 and with surface proteins previously separated by electrophoresis. Human red blood cells (HRBC) adhered to J2 of several tylenchid nematodes over the entire nematode body. HRBC adhered also to nylon fibers coated with SC extracted from M. javanica J2; binding was Ca++/Mg++ dependent, and decreased when the nylon fibers were coated with bovine serum albumin, or pre-incubated with fucose and mannose. These experiments support a working hypothesis that RBC adhesion involves carbohydrate moieties of HRBC and carbohydrate-recognition domain(s) (CRD) distributed on the nematode surface. To our knowledge, this is the first report of a surface CRD i the phylum Nematoda. Gold-conjugated lectins and neoglycoproteins combined with silver enhancement have been used for the detection of carbohydrates and CRD, respectively, on the SC of M. javanica J2. Biotin reagents were used to trace surface proteins, specifically, on live J2. The labile and transitory nature of the SC was demonstrated by the dynamics of HRBC adherence to detergent-treated J2, J2 at different ages or fresh-hatched J2 held at various temperatures. SC recovery was demonstrated also by a SDS-PAGE profile. Monoclonal antibodies developed to a cuticular protein of M. incognita J2 gave a slight, but significant reduction in attachment of Pasteuria penetrans spores. Spore attachment as affected by several enzymes was inconsistent: alcian blue, which specifically blocks sulfyl groups, had no afffect on spore attachment. Treatment with cationized ferritin alone or catonized ferritin following monoclonal antibody caused significant decreases in spore attachment. Those results suggest a role in attachment by negatively charged groups.
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Samish, Michael, K. M. Kocan, and Itamar Glazer. Entomopathogenic Nematodes as Biological Control Agents of Ticks. United States Department of Agriculture, September 1992. http://dx.doi.org/10.32747/1992.7568104.bard.
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This research project was aimed to create a basis for the use of entomopathogenic nematodes (Steinernematidae an Heterorhabditidae) for biological control of ticks. The specific objectives were to determinate: 1) Nematode virulence to various. 2) Host-parasite interactions of nametodes and ticks. 3) Effect of environmental factors of tick habitats on nematode activity. 4) To test nematodes (anti tick activity) in defined field trials. Throughout the project 12 nematode strains from five species were tested in laboratory assays against all developmental stages of eight tick species. All tick species were found susceptible to nematode infection. The nematode strains the IS-5 and IS-12 of Heterorhabditis bacteriophora were found to be the most virulent. Engorged adults, particularly females, were the most susceptible stages. Despite the high susceptibility, ticks are not suitable hosts for nematode development and propagation. Entomopathogenic namatodes enter ticks and kill them by releasing the symbiotic bacteria from their foregut. Under favorable conditions, i.e. moist soil, moderate temperature (22-27oC) and sandy soil, nematode efficacy against B. annulatus engorged females was very high (>5% w/w) and high animal manure concentration in soil adversely effect nematode efficacy. In field trails, nematodes were effective when soil moisture was maintained at high levels. The results indicate that under favorable conditions the nematodes show promise as a biological control method for ticks. However, we still face several potential obstacles to the use of nematodes under less favorable conditions.
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McClure, Michael A., Yitzhak Spiegel, David M. Bird, R. Salomon, and R. H. C. Curtis. Functional Analysis of Root-Knot Nematode Surface Coat Proteins to Develop Rational Targets for Plantibodies. United States Department of Agriculture, October 2001. http://dx.doi.org/10.32747/2001.7575284.bard.
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The goal of this research was to provide a better understanding of the interface between root-knot nematodes, Meloidogyne spp., and their host in order to develop rational targets for plantibodies and other novel methods of nematode control directed against the nematode surface coat (SC). Specific objectives were: 1. To produce additional monoclonal SC antibodies for use in Objectives 2, 3, and 4 and as candidates for development of plantibodies. 2. To determine the production and distribution of SC proteins during the infection process. 3. To use biochemical and immunological methods to perturbate the root-knot nematode SC in order to identify SC components that will serve as targets for rationally designed plantibodies. 4. To develop SC-mutant nematodes as additional tools for defining the role of the SC during infection. The external cuticular layer of nematodes is the epicuticle. In many nematodes, it is covered by a fuzzy material termed "surface coat" (SC). Since the SC is the outermost layer, it may playa role in the interaction between the nematode and its surroundings during all life stages in soil and during pathogenesis. The SC is composed mainly of proteins, carbohydrates (which can be part of glycoproteins), and lipids. SC proteins and glycoproteins have been labeled and extracted from preparasitic second-stage juveniles and adult females of Meloidogyne and specific antibodies have been raised against surface antigens. Antibodies can be used to gain more information about surface function and to isolate genes encoding for surface antigens. Characterization of surface antigens and their roles in different life-stages may be an important step towards the development of alternative control. Nevertheless, the role of the plant- parasitic nematode's surface in plant-nematode interaction is still not understood. Carbohydrates or carbohydrate-recognition domains (CROs) on the nematode surface may interact with CROs or carbohydrate molecules, on root surfaces or exudates, or be active after the nematode has penetrated into the root. Surface antigens undoubtedly play an important role in interactions with microorganisms that adhere to the nematodes. Polyclonal (PC) and monoclonal (MC) antibodies raised against Meloidogyne javanica, M. incognita and other plant-parasitic nematodes, were used to characterize the surface coat and secreted-excreted products of M. javanica and M. incognita. Some of the MC and PC antibodies raised against M. incognita showed cross-reactivity with the surface coat of M. javanica. Further characterization, in planta, of the epitopes recognized by the antibodies, showed that they were present in the parasitic juvenile stages and that the surface coat is shed during root penetration by the nematode and its migration between root cells. At the molecular level, we have followed two lines of experimentation. The first has been to identify genes encoding surface coat (SC) molecules, and we have isolated and characterized a small family of mucin genes from M. incognita. Our second approach has been to study host genes that respond to the nematode, and in particular, to the SC. Our previous work has identified a large suite of genes expressed in Lycopersicon esculentum giant cells, including the partial cDNA clone DB#131, which encodes a serine/threonine protein kinase. Isolation and predicted translation of the mature cDNA revealed a frame shift mutation in the translated region of nematode sensitive plants. By using primers homologous to conserved region of DB#131 we have identified the orthologues from three (nematode-resistant) Lycopersicon peruvianum strains and found that these plants lacked the mutation.
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Brown Horowitz, Sigal, Eric L. Davis, and Axel Elling. Dissecting interactions between root-knot nematode effectors and lipid signaling involved in plant defense. United States Department of Agriculture, January 2014. http://dx.doi.org/10.32747/2014.7598167.bard.
Full textAbstract:
Root-knot nematodes, Meloidogynespp., are extremely destructive pathogens with a cosmopolitan distribution and a host range that affects most crops. Safety and environmental concerns related to the toxicity of nematicides along with a lack of natural resistance sources threaten most crops in Israel and the U.S. This emphasizes the need to identify genes and signal mechanisms that could provide novel nematode control tactics and resistance breeding targets. The sedentary root-knot nematode (RKN) Meloidogynespp. secrete effectors in a spatial and temporal manner to interfere with and mimic multiple physiological and morphological mechanisms, leading to modifications and reprogramming of the host cells' functions, resulted in construction and maintenance of nematodes' feeding sites. For successful parasitism, many effectors act as immunomodulators, aimed to manipulate and suppress immune defense signaling triggered upon nematode invasion. Plant development and defense rely mainly on hormone regulation. Herein, a metabolomic profiling of oxylipins and hormones composition of tomato roots were performed using LC-MS/MS, indicating a fluctuation in oxylipins profile in a compatible interaction. Moreover, further attention was given to uncover the implication of WRKYs transcription factors in regulating nematode development. In addition, in order to identify genes that might interact with the lipidomic defense pathway induced by oxylipins, a RNAseq was performed by exposing M. javanicasecond-stage juveniles to tomato protoplast, 9-HOT and 13-KOD oxylipins. This transcriptome generated a total of 4682 differentially expressed genes (DEGs). Being interested in effectors, we seek for DEGs carrying a predicted secretion signal peptide. Among the DEGs including signal peptide, several had homology with known effectors in other nematode species, other unknown potentially secreted proteins may have a role as root-knot nematodes' effectors which might interact with lipid signaling. The molecular interaction of LOX proteins with the Cyst nematode effectors illustrate the nematode strategy in manipulating plant lipid signals. The function of several other effectors in manipulating plant defense signals, as well as lipids signals, weakening cell walls, attenuating feeding site function and development are still being studied in depth for several novel effectors. As direct outcome of this project, the accumulating findings will be utilized to improve our understanding of the mechanisms governing critical life-cycle phases of the parasitic M. incognita RKN, thereby facilitating design of effective controls based on perturbation of nematode behavior—without producing harmful side effects. The knowledge from this study will promote genome editing strategies aimed at developing nematode resistance in tomato and other nematode-susceptible crop species in Israel and the United States.
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Phillips, Donald A., Yitzhak Spiegel, and Howard Ferris. Optimizing nematode management by defining natural chemical bases of behavior. United States Department of Agriculture, November 2006. http://dx.doi.org/10.32747/2006.7587234.bard.
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This project was based on the hypothesis that nematodes interacting with plants as either parasites or beneficial saprophytes are attracted to their host by natural products. This concept was supported by numerous observations that parasitic nematodes are attracted to root exudates. Our overall goal was to identify nematode sensory compounds from root exudates and to use that information for reducing nematicide applications. We applied skills of the investigators to achieve three specific objectives: 1) Identify nematode behavioral cues (e.g., attractants or repellents) in root exudates; 2) Identify new natural nematicidal compounds; and 3) Combine a natural attractant and a nematicide into a nematode trap. Because saprophytic nematodes benefit plants by mineralizing organic matter, we sought compounds attractive primarily to parasitic nematodes. The project was constructed on several complementary foundations. First, data from Dr. Spiegel’s lab showed that under aseptic conditions Ditylenchus dipsaci, a parasite on onion, is attracted to certain fractions of onion root exudates. Second, PI Phillips had a sizeable collection of natural plant products he had identified from previous work on Rhizobium-legume interactions, which could be tested “off the shelf”. Third, Dr. Ferris had access to aseptic and natural populations of various saprophytic and parasitic nematodes. The project focused on five nematode species: D.dipsaci, Heterodera avenae, and Tylenchulussemipenetransat ARO, and Meloidogyne javanicand Caenorhabditis elegans at UCD. Ten pure plant compounds, mostly flavonoids, were tested on the various nematode species using six different assay systems. Results obtained with assorted test systems and by various scientists in the same test systems were essentially irreproducible. Many convincing, Many convincing, i.e. statistically significant, results in one system or with one investigator could not be repeated with other assays or different people. A recent report from others found that these compounds, plus another 30, were inactive as attractants in three additional parasitic nematode species (Wuyts et al. Nematology 8:89- 101, 2006). Assays designed to test the hypothesis that several compounds together are required to attract nematodes have thus far failed to find a reproducibly active combination. In contrast to results using pure plant compounds, complex unfractionated exudates from aseptic onion root reproducibly attracted D. dipsaci in both the ARO and UCD labs. Onion root exudate collection, separation into HPLC fractions, assays using D. dipsaci and MS-MS experiments proceeded collaboratively between ARO and UCD without any definitive identification of an active compound. The final active fraction contained two major molecules and traces of several other compounds. In the end, analytical studies were limited by the amount of onion root exudate and the complexity of the purification process. These tests showed that aseptic plant roots release attractant molecules, but whether nematodes influence that release, as insects trigger release of attractants from plants, is unknown. Related experiments showed that the saprophyte C. elegans stimulates its prey, Pseudomonas bacteria, to increase production of 2, 4-diacetylphloroglucinol (DAPG) a compound that promotes amino acid exudation by plant roots. It is thus possible that saprophytic nematodes are attracted primarily to their bacterial or fungal prey and secondarily to effects of those microorganisms on root exudation. These observations offer promising avenues for understanding root-zone interactions, but no direct routes to controlling nematodes in agriculture were evident. Extracts from two plant sources, Chrysanthemum coronarium and Sequoia sempervirens, showed nematicidal activity at ARO and UCD, respectively. Attempts to purify an active compound from S. sempervirens failed, but preliminary results from C. coronarium are judged to form a potential basis for further work at ARO. These results highlight the problems of studying complex movement patterns in sentient organisms like nematodes and the issues associated with natural product isolation from complex mixtures. Those two difficulties combined with complications now associated with obtaining US visas, slowed and ultimately limited progress on this project. As a result, US investigators expended only 65% of the $207,400 originally planned for this project. The Israeli side of the project advanced more directly toward its scientific goals and lists its expenditures in the customary financial report.
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Gaugler, Randy, Itamar Glazer, Daniel Segal, and Sarwar Hashmi. Molecular Approach for Improving the Stability of Insecticidal Nematodes. United States Department of Agriculture, November 2002. http://dx.doi.org/10.32747/2002.7580680.bard.
Full textAbstract:
Our overall goal is to improve insecticidal nematodes by genetically engineering strains capable of entering an enhanced state of dormancy that provides improved stability. Objectives: 1. Clone and sequence tps-l homologue from Steinernema carpocapsae. (Revised: A failure to isolate the tps gene group from Steinernema precipitated a redirection to identifying other genes involved in insecticidal nematode desiccation process.) 2. Incorporate cloned tps-l gene into S. carpocapsae to obtain overexpression, thereby, enhancing desiccation tolerance. (Revised: Other stress genes in addition to tps-l genes were cloned and efforts at expression in S. carpocapsae were conducted) 3. Characterize the transgenic strains. No other biological control agent offers more impressive attributes than insecticidal nematodes. However, their potential is limited by the bane of nearly all biological control agents: poor stability. This leads to inadequate shelf-life and ultimately reduced field efficacy. Nematode storage is based on desiccation, yet insecticidal species are only capable of partial desiccation termed quiescent anhydrobiosis. Overwhelming evidence has shown that when the disaccharide compound trehalose is elevated in anhydrobiotic organisms such as yeast, plants, and nematodes it enables these organisms the ability to survive environmental stresses i.e., desiccation. Armed with this information our goal was to improve insecticidal nematodes stability by engineering trehalose overexpression.
7
Glazer, Itamar, Randy Gaugler, Yitzhak Spiegel, and Edwin Lewis. Host Adaptation in Entomopathogenic Nematodes: An Approach to Enhancing Biological Control Potential. United States Department of Agriculture, April 1996. http://dx.doi.org/10.32747/1996.7613023.bard.
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The overall objective of our research was to develop methods to match species of entomopathogenic nematodes against the insect pests which they would be best adapted to control. The underlying hypothesis for this work was that entomopathogenic nematodes should be most effective when used against insect species to which they are naturally adapted to parasitize. Toward this end, we undertook a number of related studies focusing primarily on nematode foraging strategies. We found that foraging strategies affected host associations directly and indirectly. Nematodes' responses to host cues, and the role of their sensory organs based on lectin binding, led to new approaches to determining host range for these parasites. Based on this work, we developed a laboratory bioassay of host recognition behavior designed to predict field results. We also determined that nematodes that forage in a stationary manner (ambushers) have a slower metabolic rate than do active forgers (cruisers), thus their infective stage juveniles are longer lived. This study helps predict the duration of field activity after application and may partially explain field distributions of natural populations of entomopathogenic nematodes. The common thread linking all of these studies was that they led to a deeper understanding of the associations between entomopathogenic nematodes and insects as hosts.
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Bissonnette, Kaitlyn, Travis Faske, and Albert Tenuta. Soybean Cyst Nematode. United States: Crop Protection Netework, April 2021. http://dx.doi.org/10.31274/cpn-20210423-0.
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Davis, Eric L., Yuji Oka, Amit Gal-On, Todd Wehner, and Aaron Zelcer. Broad-spectrum Resistance to Root-Knot Nematodes in Transgenic Cucurbits. United States Department of Agriculture, June 2013. http://dx.doi.org/10.32747/2013.7593389.bard.
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Root-knot nematodes (RKN), Meloidogyne spp., are extremely destructive pathogens of cucurbit crops grown in the United States and Israel. The safety and environmental concerns of toxic nematicides, and limited sources of natural cucurbit resistance to the four major species of Meloidogyne that threaten these crops in Israel and the U.S., have emphasized the use of biotechnology to develop cucurbits with novel RKN resistance. The U.S. scientists have identified over 40 unique RKN parasitism genes that encode nematode secretions involved in successful plant root infection by RKN, and they have demonstrated that expression of a double-stranded RNA (dsRNA) complementary to a RKN parasitism gene (called 16DIO) in Arabidopsis thaliana induced RNA interference (RNAi)-mediated silencing of the RKN16DlO gene and produced transgenic plants with strong resistance to all four major RKN species. The expression 8D05 parasitism gene was found to coincide with the timing of upregulation of NtCel7 promoter (identified to be upregulated in giantcells by US scientists). NtCel7 promoter was used to express the genes at the right time (early stages of infection) and in the right place (giant-cells) in transgenic plants. US partners produced NtCel7 (nematode-induced promoter)-driven 16DlO-RNAi and 8DOS-RNAi constructs, pHANNIBAL 4D03-RNAi construct and modified 16DlO-RNAi construct (for increased RNAi expression and efficacy) for cucurbit transformation in Israel. In Arabidopsis, some 16DlO-RNAi plant lines show greater levels of resistance to M. incognita than others, and within these lines resistance of greater than 90% reduction in infection is observed among almost all replicates in US. The level of observed nematode resistance is likely to be directly correlated with the level of RNAi expression in individual plants. In Israel, all the RKN parasitism genes-RNAi constructs were successfully transformed into cucumber and melon. The transgenic lines were evaluated for expression of the transgene siRNA in leaves and roots. Those displaying transgene siRNA accumulation were passed on for nematode resistance analysis. Rl seedlings from different lines were subjected to evaluation for resistance to M. javanica. None of the lines was resistant to the nematode in contrast with US partner's results in Arabidopsis. This could be for the following reasons: a) The level of transgene siRNA was insufficient in cucumber and tomato to cause resislance. b) 111e nemalode species on cucwnber IIlay be different ur act in a different manner. c) The assay was performed in soil with a high level of nematode inoculation, and not in petri dish, which may not permit the observation of a low level of resistance.
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Tylka, Gregory L., Mychele Batista Da Silva, R. Aaron Saeugling, and Stephanie Marlay. Effects of Nematode-Protectant Seed Treatments on Corn Yields and Nematode Population Densities. Ames: Iowa State University, Digital Repository, 2012. http://dx.doi.org/10.31274/farmprogressreports-180814-462.
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