Artículos de revistas: "Heterorhabditis"

1

Kary, Naser Eivazian, Gholamreza Niknam, Seyed Abolgasem Mohammadi, Christine Griffin y Mohammad Moghaddam. "A survey of entomopathogenic nematodes of the families Steinernematidae and Heterorhabditidae (Nematoda: Rhabditida) in the north-west of Iran". Nematology 11, n.º 1 (2009): 107–16. http://dx.doi.org/10.1163/156854108x398453.

Texto completo

Resumen

AbstractDuring 2002-2004, a survey of entomopathogenic nematodes was conducted for the first time in Iran throughout the three provinces in the north-west of the country. Soil samples were tested for the presence of steinernematid and heterorhabditid nematodes by baiting with Galleria mellonella larvae. Of the 833 soil samples studied 27 were positive for entomopathogenic nematodes (3.2%), with 17 (2.0%) containing Heterorhabditis and ten (1.2%) Steinernema isolates. Morphological and molecular studies were carried out to characterise isolates. The Heterorhabditis isolates were identified as Heterorhabditis bacteriophora and Steinernema as Steinernema carpocapsae, S. bicornutum and S. feltiae. Heterorhabditis bacteriophora was the most common species, which was isolated from 17 sites across the three provinces. Steinernema feltiae was the most common species of Steinernema, which was isolated from eight sites but in only two provinces. Steinernema carpocapsae and S. bicornutum were each isolated from only one site. Steinernema spp. were isolated mainly from orchards and grasslands but Heterorhabditis was isolated mainly from grasslands and alfalfa fields.

Los estilos APA, Harvard, Vancouver, ISO, etc.

2

Nikdel, Mostafa, Gholamreza Niknam, Christine T. Griffin y Naser Eivazian Kary. "Diversity of entomopathogenic nematodes (Nematoda: Steinernematidae, Heterorhabditidae) from Arasbaran forests and rangelands in north-west Iran". Nematology 12, n.º 5 (2010): 767–73. http://dx.doi.org/10.1163/138855410x12628646276168.

Texto completo

Resumen

Abstract A survey for entomopathogenic nematodes (EPN) was carried out in the Arasbaran forests and rangelands, East Azarbaijan province, north-west Iran, during 2006 to 2008. A total of 691 soil samples were collected from 62 localities across the region of which 21 samples (3%) were positive for EPN, including nine samples (1.3%) with heterorhabditids and 12 (1.7%) with steinernematids. Seven isolates (four Steinernema and three Heterorhabditis) were recovered from rangelands and 14 (eight Steinernema and six Heterorhabditis) from forest soil samples. Based on morphology and molecular studies, the Heterorhabditis isolates were identified as H. bacteriophora and the Steinernema isolates as S. carpocapsae, S. bicornutum, S. feltiae, S. glaseri, S. kraussei and three undescribed species referred to here as Steinernema sp. IRAZ7, Steinernema sp. IRAZ13 and Steinernema sp. IRAZ21. Heterorhabditis bacteriophora, the most common species, was present in nine soil samples collected across the forests and rangelands, and of the Steinernema species, S. bicornutum was obtained from three samples, the other species being found from only one or two samples.

Los estilos APA, Harvard, Vancouver, ISO, etc.

3

Griffin, C. T., R. Chaerani, D. Fallon, A. P. Reid y M. J. Downes. "Occurrence and distribution of the entomopathogenic nematodes Steinernema spp. and Heterorhabditis indica in Indonesia". Journal of Helminthology 74, n.º 2 (junio de 2000): 143–50. http://dx.doi.org/10.1017/s0022149x00000196.

Texto completo

Resumen

AbstractSoil samples from 79 sites on five islands of Indonesia were baited with insects for the recovery of entomopathogenic nematodes. Heterorhabditis and Steinernema were equally prevalent, and were recovered from 11.7% of samples representing 20.3% of sites sampled. Both genera were recovered from coastal sites only. Entomopathogenic nematodes were more prevalent on the Moluccan islands of Ambon and Seram than on Java or Bali. They were not detected on Sulawesi, where non-coastal sites only were sampled. RFLP analysis was used in the identification of nematode isolates. Heterorhabditis indica was the only heterorhabditid identified. Two RFLP types ofSteinernema were identified.

Los estilos APA, Harvard, Vancouver, ISO, etc.

4

Mason, J. M., A. R. Razak y D. J. Wright. "The recovery of entomopathogenic nematodes from selected areas within Peninsular Malaysia". Journal of Helminthology 70, n.º 4 (diciembre de 1996): 303–7. http://dx.doi.org/10.1017/s0022149x00015595.

Texto completo

Resumen

AbstractSoil sampling was conducted within Peninsular Malaysia with the aim of recovering entomopathogenic nematodes (Steinernematidae and Heterorhabditidae). Extensive sampling was performed in the Cameron Highlands, which are climatically distinct from the lowlands, and characterized by lower temperature and humidity. The major areas sampled in the lowlands were at the campus of Universiti Pertanian Malaysia (orchards and plantations), Puchong (secondary rainforest) and along the east coast of the country. Entomopathogenic nematodes were recovered using the Galleria mellonella baiting method. Nematodes were recovered from 10% of the 425 samples assayed. Identifications, using a PCR method, revealed that the 21 identified steinernematids belonged to two different genetic types and that four out of the five heterorhabditids were Heterorhabditis indicus, the remaining heterorhabditid being a new species. The nematodes are currently being screened to evaluate their biocontrol potential for use in Malaysia against foliage-feeding lepidopteran pests of crucifers.

Los estilos APA, Harvard, Vancouver, ISO, etc.

5

Griffin, Christine T., Ilona Dix, Susan A. Joyce, Ann M. Burnell y Martin J. Downes. "Isolation and characterisation of Heterorhabditis spp. (Nematoda: Heterorhabditidae) from Hungary, Estonia and Denmark". Nematology 1, n.º 3 (1999): 321–32. http://dx.doi.org/10.1163/156854199508199.

Texto completo

Resumen

Abstract Targeted surveys were conducted for the entomopathogenic nematode Heterorhabditis in areas of Denmark, Estonia and Hungary. Isolates were identified by IEF, PCR and cross-fertility tests as belonging to three distinct taxonomic groups: H. bacteriophora, the north-west European (NWE) type of H. megidis and the Irish type of Heterorhabditis. The Irish and NWE types of Heterorhabditis were both present in Denmark (at six and four sites, respectively), while only the NWE type was recovered in Estonia. H. bacteriophora was the dominant heterorhabditid identified in Hungary (ten sites), but the Irish type was also detected at two sites. This is the first report of the Irish type of Heterorhabditis on continental Europe. Co-occurrence of two Heterorhabditis types at a single site was noted in Denmark (Irish and NWE) and in Hungary (Irish and H. bacteriophora). Heterorhabditis was recovered at 38.5% of sites (n = 26) in Denmark (north coast of Sjaelland), 27.3% of the coastal sites (n = 22) in Estonia, and 32.6% of sites (n = 46) in Hungary. Isolation et caracterisation d'especes d'Heterorhabditis (Nematoda: Heterorhabditidae) originaires de Hongrie, d'Estonie et du Danemark - Des prospections ciblees ont ete effectuees dans certaines regions du Danemark, d'Estonie et de Hongrie pour rechercher les nematodes du genre Heterorhabditis. Les souches, identifiees par les methodes de concentration isoelectrique, de PCR et d'hybridation, appartiennent aux trois groupes taxinomiques d'Heterorhabditis : H. bacteriophora, le groupe de l'Europe du nord-ouest (NWE) de H. megidis et le groupe irlandais d'Heterorhabditis. Le groupe irlandais et le groupe NWE sont tous les deux presents au Danemark (dans six et quatre sites, respectivement), mais seul le dernier groupe a ete rencontre en Estonie. H. bacteriophora, present dans dix sites, est l'espece dominante d'Heterorhabditis en Hongrie, mais le groupe irlandais a ete egalement detecte dans deux sites. C'est la premiere fois que le groupe irlandais est rencontre en Europe continentale. La presence simultanee de deux types d'Heterorhabditis est signalee au Danemark (groupe irlandais et groupe NWE) et en Hongrie (groupe irlandais et H. bacteriophora). Des Heterorhabditis ont ete collectes sur 38.5% des 26 sites du Danemark (cote nord de Sjaelland), 27.3% des 22 sites du littoral estonien et 32.6% des 46 sites de Hongrie.

Los estilos APA, Harvard, Vancouver, ISO, etc.

6

O'LEARY, S. A., A. M. BURNELL y J. R. KUSEL. "Biophysical properties of the surface of desiccation-tolerant mutants and parental strain of the entomopathogenic nematode Heterorhabditis megidis (strain UK211)". Parasitology 117, n.º 4 (octubre de 1998): 337–45. http://dx.doi.org/10.1017/s0031182098003151.

Texto completo

Resumen

Entomopathogenic nematodes (EPN) are useful biological control agents of insect pests. However, the infective juvenile (IJ) stage which is the only stage to occur outside the host is susceptible to environmental extremes such as desiccation. We have isolated desiccation-tolerant strains of the EPN Heterorhabditis megidis. In this paper we describe the surface properties of these desiccation-tolerant mutants. Heterorhabditid IJs retain the sheath of the previous larval stage. The mutant lines possess alterations in the surface properties of the sheath. Differences were observed in fluorescent lipid analogue insertion into the surface of the sheath. Furthermore, cationized ferritin-binding studies demonstrated that the mutant lines possessed an increase in net negative surface charge. Removal of the surface layer of the sheath resulted in the loss of the mutant phenotype and in a reduction in the desiccation tolerance of the parental strain. Therefore, the negatively charged ‘surface coat’ appears to play an important role in the desiccation tolerance of Heterorhabditis species.

Los estilos APA, Harvard, Vancouver, ISO, etc.

7

Santos, Viviane, Alcides Moino Junior, Vanessa Andaló, Camila Costa Moreira y Ricardo Alves de Olinda. "Virulence of entomopathogenic nematodes (Rhabditida: Steinernematidae and Heterorhabditidae) for the control of Diabrotica speciosa germar (coleoptera: chrysomelidae)". Ciência e Agrotecnologia 35, n.º 6 (diciembre de 2011): 1149–56. http://dx.doi.org/10.1590/s1413-70542011000600015.

Texto completo

Resumen

Entomopathogenic nematodes (EPNs) are used in biological control of soil insects and show promise in the control of D. speciosa. The objective of this work was to evaluate the potential of native and exotic entomopathogenic nematode isolates in the control of D. speciosa under laboratory and greenhouse conditions. Results showed that all of EPNs caused larval mortality. The most virulent were Heterorhabditis sp. RSC01 (94%), Steinernema glaseri (84%), Heterorhabditis sp. JPM04 (82%) and Heterorhabditis amazonensis RSC05 (78%). There was no effect of the Heterorhabditis sp. RSC01 and S. glaseri isolates on eggs. The maximum mortality of D. speciosa larvae by Heterorhabditis sp. RSC01 was observed at a concentration of 300 IJ/ insect, while by S. glaseri observed the highest mortality at the concentration of 200 IJ/ insect. The Heterorhabditis sp. RSC01 isolate caused over 80% pupal mortality at a concentration of 250 IJ/insect. The virulence of Heterorhabditis sp. RSC01 and S. glaseri was affected by temperature. The Heterorhabditis sp. RSC01 isolate caused reduction in larva survival under greenhouse conditions at all of the tested concentrations and there was no difference in mortality among different concentrations of infectid juveniles.

Los estilos APA, Harvard, Vancouver, ISO, etc.

8

Majić, Ivana, Ankica Sarajlić, Tamás Lakatos, Tímea Tóth, Emilija Raspudić, Zlatko Puškadija, Gabriella Kanižai Šarić y Žiga Laznik. "Virulence of new strain of Heterorhabditis bacteriophora from Croatia against Lasioptera rubi". Plant Protection Science 55, No. 2 (17 de febrero de 2019): 134–41. http://dx.doi.org/10.17221/119/2018-pps.

Texto completo

Resumen

Soil samples from 100 cultivated and natural sites were assessed for the presence of entomopathogenic nematodes. Heterorhabditid nematodes were recovered from three soil samples during spring months, with the overall positive sample rate of 3%. The isolates of entomopathogenic nematodes were identified as three different strains conspecific with Heterorhabditis bacteriophora (Heterorhabditidae). They were found from natural sites and vineyard, while no recovery occurred from intensively cultivated agricultural fields. The morphometrical characteristics of infective juveniles and males showed differences between all Croatian strains and from the original description. Heterorhabditis bacteriophora ISO9 was bioassayed on Lasioptera rubi (Cecidomyiidae) (the raspberry gall midge) larvae at different nematode concentrations under laboratory conditions. The significantly highest mortality was observed in treatments with 50 and 200 infective juveniles per insect larvae within 8 days after inoculation. This is the first report of entomopathogenic nematodes of the family Heterorhabditidae from Croatia, and susceptibility of L. rubi larvae to entomopathogenic nematodes. The Croatian strain H. bacteriophora ISO9 was proved to possess strong insecticidal properties against L. rubi larvae.

Los estilos APA, Harvard, Vancouver, ISO, etc.

9

Alves, V. S., A. Moino Junior, L. V. C. Santa-Cecilia, V. Andaló y G. C. Souza. "PATOGENICIDADE DE NEMATÓIDES ENTOMOPATOGÊNICOS A COCHONILHA-DARAIZ-DO-CAFEEIRO DYSMICOCCUS TEXENSIS (TINSLEY) (HEMIPTERA: PSEUDOCOCCIDAE) EM LABORATÓRIO". Arquivos do Instituto Biológico 76, n.º 1 (marzo de 2009): 67–73. http://dx.doi.org/10.1590/1808-1657v76p0672009.

Texto completo

Resumen

RESUMO A cochonilha-da-raiz-do-cafeeiro Dysmicoccus texensis (Tinsley) ataca as raízes desta planta, podendo causar sérios danos às plantações e conseqüentes perdas na produção. Os nematóides entomopatogênicos (NEPs) são agentes eficientes no controle de várias pragas encontradas no solo, o que sugere provável eficiência no controle da cochonilha-da-raiz-do-cafeeiro. Dessa forma, este trabalho teve por objetivo avaliar a patogenicidade de alguns isolados de NEPs à cochonilhada-raíz-do-cafeeiro através de testes de seleção de isolados, determinação da concentração letal máxima (CLM99) e patogenicidade a criptas coletadas no campo. Os isolados Heterorhabditis sp. CCA, Heterorhabditis bacteriophora, Heterorhabditis sp. JPM3.1 e Heterorhabditis sp. JPM3 foram os que apresentaram maior virulência, alcançando valores máximos de mortalidade de 100, 94, 94 e 82%, respectivamente, na maior concentração testada (100 juvenis infectantes (JI)/inseto). A CL99 determinada para Heterorhabditis sp. CCA foi estimada em 530 JI/placa. Valor semelhante foi encontrado para Heterorhabditis sp. JPM3 que teve a CL99 igual a 560 JI/placa. Estimando a concentração por área, o valor obtido para Heterorhabditis sp. CCA e Heterorhabditis sp. JPM3 foi de 28 e 29 JI/cm2, respectivamente. No teste realizado com criptas, ambos os isolados de NEPs foram patogênicos aos insetos.

Los estilos APA, Harvard, Vancouver, ISO, etc.

10

Guide, Bruna Aparecida, Viviane Sandra Alves, Thiago Augusto Paes Fernandes, Matheus Corseti Marcomini, Ana Maria Meneguim y Pedro Manuel Oliveira Janeiro Neves. "Selection of entomopathogenic nematodes and evaluation of their compatibility with cyantraniliprole for the control of Hypothenemus hampei". Semina: Ciências Agrárias 39, n.º 4 (2 de agosto de 2018): 1489. http://dx.doi.org/10.5433/1679-0359.2018v39n4p1489.

Texto completo

Resumen

Attack by the coffee berry borer Hypothenemus hampei causes significant damage to coffee crops because it affects the quality of the coffee fruit during different developmental stages, which results in production losses. Control of the borer is difficult owing to its cryptic behavior and the fact that it spends its entire life cycle inside the coffee berries. This makes it difficult for natural enemies to reach it, as well as for it to come into contact with chemical insecticides. The objective of the present study was to select and evaluate the virulence of entomopathogenic nematodes (EPNs) on the coffee berry borer H. hampei and their compatibility with the insecticide cyantraniliprole under laboratory conditions. Initially, the pathogenicity and virulence of 16 isolates of Steinernema and Heterorhabditis towards coffee berry borer larvae and adults were evaluated. The most virulent isolates to both larvae and adults were determined by topical inoculation tests in coffee fruits (berries) infested by the insect, using a concentration of 100 infective juveniles (IJs)/fruit. The same isolates were also evaluated for viability and infectivity when combined with cyantraniliprole. The isolates S. feltiae (IBCB-n 47) and Heterorhabditis amazonensis (GL) displayed the highest virulence towards adults (54%). For larvae, we observed a high virulence of S. feltiae, Heterorhabditis amazonensis, Heterorhabditis indica, Heterorhabditis sp. (JPM4), Heterorhabditis sp. (NEPET 11), Heterorhabditis sp. (IBCB-n 46), and Heterorhabditis sp. (IBCB-n 44) that promoted 100% mortality. Regarding the topical inoculation test on infested fruits, S. feltiae and Heterorhabditis sp. (IBCB-n 46) were unable to penetrate the fruit through the hole made by the borer, infect, and cause the death of insects. Cyantraniliprole formulation affected the viability of IJs of S. feltiae and Heterorhabditis sp. (IBCB-n 46), mainly after 48 h of exposure.

Los estilos APA, Harvard, Vancouver, ISO, etc.

11

Qian, Xiu Juan, Li Na Gu, Yu Fang Xing y Chang ZHong Liu. "Entomopathogenic Nematodes Isolated from Gansu Province and Four New Species in China". Applied Mechanics and Materials 651-653 (septiembre de 2014): 328–36. http://dx.doi.org/10.4028/www.scientific.net/amm.651-653.328.

Texto completo

Resumen

With the morphological characters, anatomy and molecular biology research, 29 entomopathogenic nematodes populations isolated from Gansu province were identified and the resoult showed that they were 8 species of EPN, Steinernema feltiae,Steinernema bicornutum,Steinernema affin,Steinernema krusse and Steinernema karil were belong to Steinernema while Heterorhabditis brevicaudis,Heterorhabditis megidi and Heterorhabditis marelatu were belong to Heterorhabditis respectively. And what more research found that S. affin,S. krusse,S. karil and H. marelatu were new species in China.

Los estilos APA, Harvard, Vancouver, ISO, etc.

12

Qodiriyah, Qodiriyah, Didik Sulistyanto y Purwatiningsih Purwatiningsih. "Biological Control Entomopathogenic Nematodes Heterorhabditis sp. and Steinernema sp. Pest Control Termite Land As Coptotermes sp. and Microtermes sp. in The District Lumajang". Jurnal ILMU DASAR 16, n.º 1 (30 de octubre de 2015): 43. http://dx.doi.org/10.19184/jid.v16i1.1518.

Texto completo

Resumen

This research aims to find out the most effective concentration (LC50) and the most effective time (LT50) and to select a biological agent netamoda of nematodes Steinernema sp. dan Heterorhabditis sp. as the environmentally friendly biological control agents on the ground termite Coptotermes sp. and Microtermes sp. in Lumajang. All the data were analyzed by using the termite mortality percentage variance analysis. The LC50 and LT50 were tested by using the probit analysis. Therefore, the empirical probit values were obtained from the percentage of mortality after they were calculated by the Abbot formulation. The biological agents netamoda entomopathogenic Heterorhabditis sp. and Steinernema sp. had the high value on the pathogenicity of Coptotermes sp. and Microtermes sp., the LC50 values on Coptotermes sp. of nematodes Heterorhabditis sp. was 14.94 IJ/ml and Steinernema sp. was 15.22 IJ/ml., the LC50 values on Microtermes sp. of nematodes Heterorhabditis sp. was 16.54 IJ/ml and Steinernema sp. was 20.39 IJ/ml., the LT50 values on Coptotermes sp. of nematodes Heterorhabditis sp. was 1.29 hours and Steinernema sp. was 1.35 hours, and the LT50 values on Microtermes sp. of nematodes Heterorhabditis sp. was 2.14 hours and Steinernema sp. was 1.82 hours. Through pathogenicity test, the entomopathogenic nematodes Heterorhabditis sp. is more effective to control subterranean termites compared with the nematode Steinernema sp. This happens because Heterorhabditis sp. are actively engaged and looking for a host so that there are a large number of possibilities of contacting them with a very large subterranean termites.Keywords: Entomopathogenic nematodes, Heterorhabditis sp., Steinernema sp., LC50, LT50

Los estilos APA, Harvard, Vancouver, ISO, etc.

13

Nguyen, Ngoc Chau, Ke Long Phan, Maurice Moens y Sergei Subbotin. "Heterorhabditis baujardi sp. n. (Rhabditida: Heterorhabditidae) from Vietnam and morphometric data for H. indica populations". Nematology 5, n.º 3 (2003): 367–82. http://dx.doi.org/10.1163/156854103769224368.

Texto completo

Resumen

AbstractA survey of entomopathogenic nematodes in Vietnam yielded several Heterorhabditis isolates. The majority belonged to H. indica; their morphometrics are given in this paper. Three isolates collected in forests in Backan, Ninhbinh and Kontum provinces, Vietnam are here described as a new species Heterorhabditis baujardi sp. n. The new species is distinguished from the other ten valid Heterorhabditis species by a combination of morphological, morphometrical, and DNA characters. Heterorhabditis baujardi sp. n. is morphometrically similar to H. indica, but can be separated from this species by the shape of the gubernaculum and the number of normal pairs of genital papillae. The gubernaculum of H. baujardi sp. n. with the proximal end ventrally curved resembles that of H. bacteriophora. Heterorhabditis baujardi sp. n. can be separated from this latter species by a shorter body length of infective juveniles and longer spicules, longer gubernaculum, and a higher spicule length to anal body diameter ratio of males. The canonical discriminant analysis of morphometrical characters of both infective juveniles and males failed to discriminate Heterorhabditis baujardi sp. n. from H. indica. However, the new species was easily distinguished from H. downesi, H. marelatus, H. megidis and H. bacteriophora. Heterorhabditis baujardi sp. n. was slightly separated from H. bacteriophora by variables of the infective juveniles, but was clearly distinguished by variables of the males. Cross-breeding tests using isolates of the new species and H.indica did not yield fertile progeny. Analysis of the ITS1 sequence of rDNA of H. baujardi sp. n. revealed substantial differences with other known ITS1 Heterorhabditis sequences. Phylogenetic relationships between Heterorhabditis species and the usefulness of morphological and molecular characters for identification of species from this group are discussed.

Los estilos APA, Harvard, Vancouver, ISO, etc.

14

Maulida, Hawwa' Cahya, Saiku Rokhim y Erna Zahro’in. "Patogenitas Nematoda Entomopatogen Heterorhabditis spp. Terhadap Larva Spodoptera litura". JURNAL Al-AZHAR INDONESIA SERI SAINS DAN TEKNOLOGI 6, n.º 2 (27 de septiembre de 2021): 96. http://dx.doi.org/10.36722/sst.v6i2.809.

Texto completo

Resumen

Spodoptera litura is a pest in vegetable plants that attacks the leaves and stems. Damage arising from the attack of S. litura can decrease the productivity of plants. Synthetic pesticides are often used in controlling the population of S. litura, but synthetic pesticides have a high negative impact. Potential entomopathogenic nematode Heterorhabditis spp. believed to be effective for controlling pest populations. This study aims to find out the pathogenic value of entomopathogenic nematode Heterorhabditis spp. to the larvae of S. litura. Based on the results obtained Heterorhabditis spp. has a positive influence in causing mortality in the larvae of S. litura. Heterorhabditis spp. mortality of up to 42%. Symptoms indicated by larvae of S. litura affected by Heterorhabditis spp. among them the behavior becomes passive, the body becomes flaccid, the cuticle turns red and the tissues inside the body are destroyed. Obtained pathogenicity value Lc 50 Heterorhabditis spp. 7,690 IJ/ml, as for the factors affecting Heterorhabditis spp. such as humidity, temperature, pH, and light intensity.Keywords – Entomopathogenic Nematodes, Pathogenicity, Spodoptera litura

Los estilos APA, Harvard, Vancouver, ISO, etc.

15

Gaudriault, S., E. Duchaud, A. Lanois, A. S. Canoy, S. Bourot, R. DeRose, F. Kunst, N. Boemare y A. Givaudan. "Whole-Genome Comparison between Photorhabdus Strains To Identify Genomic Regions Involved in the Specificity of Nematode Interaction". Journal of Bacteriology 188, n.º 2 (15 de enero de 2006): 809–14. http://dx.doi.org/10.1128/jb.188.2.809-814.2006.

Texto completo

Resumen

ABSTRACT The bacterium Photorhabdus establishes a highly specific association with Heterorhabditis, its nematode host. Photorhabdus strains associated with Heterorhabditis bacteriophora or Heterorhabditis megidis were compared using a Photorhabdus DNA microarray. We describe 31 regions belonging to the Photorhabdus flexible gene pool. Distribution analysis of regions among the Photorhabdus genus identified loci possibly involved in nematode specificity.

Los estilos APA, Harvard, Vancouver, ISO, etc.

16

Ferreira, Tiarin, Carol A. van Reenen, Akihito Endo, Patrick Tailliez, Sylvie Pagès, Cathrin Spröer, Antoinette P. Malan y Leon M. T. Dicks. "Photorhabdus heterorhabditis sp. nov., a symbiont of the entomopathogenic nematode Heterorhabditis zealandica". International Journal of Systematic and Evolutionary Microbiology 64, Pt_5 (1 de mayo de 2014): 1540–45. http://dx.doi.org/10.1099/ijs.0.059840-0.

Texto completo

Resumen

The bacterial symbionts SF41T and SF783 were isolated from populations of the insect pathogenic nematode Heterorhabditis zealandica collected in South Africa. Both strains were closely related to strain Q614 isolated from a population of Heterorhabditis sp. collected from soil in Australia in the 1980s. Sequence analysis based on a multigene approach, DNA–DNA hybridization data and phenotypic traits showed that strains SF41T, SF783 and Q614 belong to the same species of the genus Photorhabdus with Photorhabdus temperata subsp. cinerea as the most closely related taxon (DNA–DNA hybridization value of 68 %). Moreover, the phylogenetic position of Photorhabdus temperata subsp. cinerea DSM 19724T initially determined using the gyrB sequences, was reconsidered in the light of the data obtained by our multigene approach and DNA–DNA hybridization experiments. Strains SF41T, SF783 and Q614 represent a novel species of the genus Photorhabdus , for which the name Photorhabdus heterorhabditis sp. nov. is proposed (type strain SF41T = ATCC BAA-2479T = DSM 25263T).

Los estilos APA, Harvard, Vancouver, ISO, etc.

17

Achinelly, M. F., D. P. Eliceche, M. N. Belaich y P. D. Ghiringhelli. "Variability study of entomopathogenic nematode populations (Heterorhabditidae) from Argentina". Brazilian Journal of Biology 77, n.º 3 (24 de octubre de 2016): 569–79. http://dx.doi.org/10.1590/1519-6984.20015.

Texto completo

Resumen

Abstract Entomopathogenic nematodes (EPN) belonging to the Heterorhabditidae family are lethal parasites of soil-dwelling insects. Two species were reported in Argentina: Heterorhabditis argentinensis and Heterorhabditis bacteriophora characterized mainly by morphometric features. In this work a comparative and phylogenetic study between five Heterorhabditis populations from Argentina was conducted to analyze the variability between strains and to evaluate the taxonomic position of Heterorhabditis argentinensis. The PCA analyses of morphometric characters separated the larger juvenile, female and male H. argentinensis from H. bacteriophora populations. The juvenile (IJs) stage provided the clearest separation of Heterorhabditis populations presenting the least variability between strains. The variable L and MBW were highly related to H. argentinensis IJs. Three groups were separated by this stage considering PC1 and PC2: one formed by H. bacteriophora OLI, RIV and RN strains, (isolates from Córdoba and Río Negro province), one for H. bacteriophora VELI strain (Buenos Aires province) and one for H. argentinensis (Santa Fe province). Heterorhabditis bacteriophora VELI and H. argentinensis isolated from regions with more rainfalls and humidity presented larger values for morphometric features. Molecular analyses showed the Argentinian populations (H. bacteriophora VELI strain and H. argentinensis), forming a same clade, with six other H. bacteriophora populations (not from Argentina) with a genetic similarity between them of 99%. Heterorhabditis argentinensis presented one unique nucleotide that was not present in any of the other species of the clade. Considering the results of this study H. argentinensis would be conspecific to H. bacteriophora, constituting a strain with a great morphometric variation where the host and climatic conditions could have influenced on the measurements.

Los estilos APA, Harvard, Vancouver, ISO, etc.

18

Hu, Kaiji, Jianxiong Li y John M. Webster. "Nematicidal metabolites produced by Photorhabdus luminescens (Enterobacteriaceae), bacterial symbiont of entomopathogenic nematodes". Nematology 1, n.º 5 (1999): 457–69. http://dx.doi.org/10.1163/156854199508469.

Texto completo

Resumen

Abstract The secondary metabolites, 3,5-dihydroxy-4-isopropylstilbene (ST) and indole, from the culture filtrate of Photorhabdus luminescens MD, were shown to have nematicidal properties. ST caused nearly 100% mortality of J4 and adults of Aphelenchoides rhytium , Bursaphelenchus spp. and Caenorhabditis elegans at 100 mu g/ml, but had no effect on J2 of Meloidogyne incognita or infective juveniles (IJ) of Heterorhabditis megidis at 200 mu g/ml. Indole was lethal to several nematode species at 300 mu g/ml, and caused a high percentage of Bursaphelenchus spp. (J4 and adults), M. incognita (J2) and Heterorhabditis spp. (IJ) to be paralysed at 300, 100 and 400 mu g/ml, respectively. Both ST and indole inhibited egg hatch of M. incognita . ST repelled IJ of some Steinernema spp. but not IJ of Heterorhabditis spp., and indole repelled IJ of some species of both Steinernema and Heterorhabditis . ST, but not indole, was produced in nematode-infected larval Galleria mellonella after 24 h infection. Von Photorhabdus luminescens (Enterobacteriaceae), einem Symbionten entomopathogener Nematoden gebildete nematizide Metaboliten - Es wurde gezeigt, dass die Sekundarmetaboliten 3,5-Dihydroxy-4-isopropylstilben (ST) und Indol aus dem Kulturfiltrat von Photorhabdus luminescens MD nematizide Eigenschaften besassen. In einer Konzentration von 100 mu g/ml verursachte ST eine fast 100%ige Sterblichkeit bei J4 und Adulten von Aphelenchoides rhytium , Bursaphelenchus spp. und Caenorhabditis elegans , hatte aber bei 200 mu g/ml keine Wirkung auf J2 von Meloidogyne incognita oder auf Infektionsjuvenile (IJ) von Heterorhabditis megidis . Bei 300 mu g/ml war Indol fur etliche Nematodenarten todlich und fuhrte dazu, dass Bursaphelenchus spp. (J4 and Adulte) bei 300, M. incognita (J2) bei 100, und Heterorhabditis spp. (IJ) bei 400 mu g/ml zu einem grossen Teil gelahmt wurden. ST und Indol behinderten beide das Schlupfen von M. incognita . ST wirkte abstossend auf IJ einiger Steinernema -Arten aber nicht auf IJ von Heterorhabditis spp., und Indol wirkte abstossend auf IJ einiger Arten der beiden Gattungen Steinernema und Heterorhabditis . ST wurde in nematoden-befallenen Larven von Galleria mellonella 24 h nach der Infektion gebildet, Indol dagegen nicht.

Los estilos APA, Harvard, Vancouver, ISO, etc.

19

Dix, I., A. M. Burnell, C. T. Griffin, S. A. Joyce, M. J. Nugent y M. J. Downes. "The identification of biological species in the genus Heterorhabditis (Nematoda: Heterorhabditidae) by cross-breeding second-generation amphimictic adults". Parasitology 104, n.º 3 (junio de 1992): 509–18. http://dx.doi.org/10.1017/s0031182000063770.

Texto completo

Resumen

Entomopathogenic nematodes of the genus Heterorhabditis are morphologically conservative, consequently the majority of isolates remain unassigned at the species level. When a Heterorhabditis infective juvenile infects an insect host, it develops into a protandrous hermaphrodite female. These first-generation females give rise to a second generation which contains both males and females. Because of this complex life-cycle and also because of uncertainty as to whether second-generation females are amphimictic, cross-breeding studies to facilitate species determination have not been carried out previously. We demonstrate here that second-generation Heterorhabditis females are amphimictic. Because of this finding, we have been able to develop a successful cross-breeding technique for the purposes of species determination in Heterorhabditis. Interstrain crosses using second-generation males and females from the appropriate strains have been successfully set up in Xenorhabdus luminescens-treated G. mellonella cadavers and also on agar plates. Using the techniques described here we confirm that H. bacteriophora (Brecon strain), H. megidis and H. zealandica are distinct biological species, we note that the H. bacteriophora group contains at least 2 species and we provide evidence for the existence of a new Irish species of Heterorhabditis.

Los estilos APA, Harvard, Vancouver, ISO, etc.

20

Giometti, Fernando Henrique Carvalho, Luís Garrigós Leite, Fernando Martins Tavares, Fábio Silber Schmit, Antonio Batista Filho y Raphaela Dell'Acqua. "Virulência de nematóides entomopatogênicos (Nematoda: Rhabditida) a Sphenophorus levis (Coleoptera: Curculionidae)". Bragantia 70, n.º 1 (2011): 81–86. http://dx.doi.org/10.1590/s0006-87052011000100013.

Texto completo

Resumen

O bicudo da cana-de-açúcar, Sphenophorus levis (Coleoptera: Curculionidae), é uma importante praga de solo dos canaviais no Estado de São Paulo, ocasionando prejuízos de até 30 t de cana/ha/ano. Visando ao controle biológico desta praga, esse estudo teve por objetivo avaliar a virulência de 17 isolados de nematóides entomopatogênicos do gênero Steinernema e Heterorhabditis contra adultos de S. levis, e o efeito dos quatro nematóides mais virulentos em três dosagens cada um. A pesquisa foi realizada em condições de laboratório, sendo realizados quatro ensaios para o estudo de virulência. Os nematóides selecionados como mais virulentos em cada teste foram S. brazilense IBCB n6, Heterorhabditis sp. IBCB n10, Heterorhabditis sp. IBCB n24 e Heterorhabditis sp. IBCB n44, sendo os únicos que diferenciaram significativamente das respectivas testemunhas com 45%, 40%, 20% e 31% de mortalidade do inseto na concentração de 240 juvenis infectivos (JI)/inseto. No teste de dose, os isolados de Heterorhabditis identificados como IBCB n10, IBCB n24 e IBCB n44 destacaram-se quanto à virulência para os adultos do bicudo da cana-de-açúcar, diferindo significativamente da testemunha na maior dose avaliada (1200 JI/inseto) com níveis de mortalidade do inseto de 60%, 65,7% e 74,3% respectivamente.

Los estilos APA, Harvard, Vancouver, ISO, etc.

21

López-Núñez, Juan Carlos, Liliana Cano, Carmenza Góngora-B. y S. Patricia Stock. "Diversity and evolutionary relationships of entomopathogenic nematodes (Steinernematidae and Heterorhabditidae) from the Central Andean region of Colombia". Nematology 9, n.º 3 (2007): 333–41. http://dx.doi.org/10.1163/156854107781351972.

Texto completo

Resumen

Abstract A survey of entomopathogenic nematodes (EPN) was conducted in the Central Andean region of Colombia. Out of a total of 945 soil samples, 28 (3%) were positive for entomopathogenic nematodes. Of them, 26 samples (92.8%) contained Steinernema and two (7.2%) harboured Heterorhabditis isolates. Characterisation of the recovered isolates was done by analysis of rDNA sequences. The large subunit of rDNA (28S) was considered for diagnosis of Steinernema species whereas the internal transcribed spacer region (ITS) of rDNA was used to identify Heterorhabditis isolates recovered in this study. Five Steinernema spp. were isolated and identified as S. websteri and four new, undescribed species. Steinernema websteri was isolated from two sites: Naranjal and Paraguaicito stations. At Naranjal, this species was recovered from a coffee plantation and a forest habitat surrounding these plantations. At Paraguaicito, the same species was recovered from a coffee-guamo habitat. Steinernema sp. 1 was collected from nogal cafetero (Cordia allaidora) groves and forest habitats at Paraguaicito station. Steinernema sp. 2 was found in coffee-guamo habitats both at Naranjal and Paraguaicito stations. Steinernema sp. 3 was the only EPN species recovered at Santa Barbara station in association with plantain. This species was also found at La Catalina station in association with forest habitats and also from soil samples taken from a landscaped area with Heliconia sp. and grass cover (Arachis pintoi) at Cenicafé La Granja station and a coffee-guamo habitat at Naranjal station. Steinernema sp. 4 was found at La Catalina in a forest habitat, also associated with Steinernema sp. 3 (isolate JCL002) and Heterorhabditis sp. 1 (isolate JCL 003). The Heterorhabditis isolates were identified as two undescribed Heterorhabditis spp. Heterorhabditis sp. 1 (isolate JCL003) was recovered at La Catalina station associated with a forest habitat. Heterorhabditis sp. 2 (isolate JCL040) was collected from a coffee-guamo habitat at Naranjal station. Although limited to one geographic region, this study suggests entomopathogenic nematodes in Colombia are quite diverse and are perhaps widely distributed in this country. A more intensive survey covering all geographic regions is currently underway.

Los estilos APA, Harvard, Vancouver, ISO, etc.

22

Morris, O. N. y V. Converse. "EFFECTIVENESS OF STEINERNEMATID AND HETERORHABDITID NEMATODES AGAINST NOCTUID, PYRALID, AND GEOMETRID SPECIES IN SOIL". Canadian Entomologist 123, n.º 1 (febrero de 1991): 55–61. http://dx.doi.org/10.4039/ent12355-1.

Texto completo

Resumen

AbstractLarvae of one pyralid, five noctuid, and one geometrid species were exposed to six species/strains of steinernematid and two species of heterorhabditid nematodes applied to soil surface in the laboratory. The most parasitic nematodes were Steinernema bibionis Bovien for the wax moth (Galleria mellonella L.) and the bertha armyworm (Mamestra configurata Wlk.), Heterorhabditis heliothidis (Khan, Brooks, and Hirschmann) for the cereal armyworm [Pseudaletia unipuncta (Haw)], S. feltiae Filipjev Mexican for the variegated cutworm [Peridroma saucia (Hbn.)], and S. feltiae All for the red-backed cutworm [Euxoa ochrogaster (Gwen)] and the spring cankerworm [Paleacrita vernata (Peck.)]. When both LD50 values and rates of parasitism of the hosts were considered together, the most promising nematode for soil applications was S. feltiae against the bertha armyworm.

Los estilos APA, Harvard, Vancouver, ISO, etc.

23

Grenier, E., E. Bonifassi, P. Abad y C. Laumond. "Use of species-specific satellite DNAs as diagnostic probes in the identification of Steinernematidae and Heterorhabditidae entomopathogenic nematodes". Parasitology 113, n.º 5 (noviembre de 1996): 483–89. http://dx.doi.org/10.1017/s0031182000081555.

Texto completo

Resumen

SUMMARYThree satellite DNAs previously isolated from the entomopathogenic nematodes Steinernema carpocapsae, Heterorhabditis bacteriophora and Heterorhabditis indicus give hybridization signals only with the S. carpocapsae, H. bacteriophora and H. indicus populations tested, indicating that these satellite sequences are species-specific. Because of their reiteration and their variabilities, we have shown that these sequences are able to discriminate at the interspecific level between the Steinernema and Heterorhabditis species, but also at the intraspecific level between S. carpocapsae strains. Furthermore, in simple squashed nematode experiments, we are able to unambiguously identify S. carpocapsae, H. bacteriophora and H. indicus populations. This last procedure is effective even on a single infective juvenile, with the main advantage that it avoids time-consuming DNA extractions.

Los estilos APA, Harvard, Vancouver, ISO, etc.

24

Kovtun, A. M. "Entomonematologic studies of the agrocenoses of Ukraine as a source of identification of the factors of the potential biocontrol of plant insects". Interdepartmental Thematic Scientific Collection of Plant Protection and Quarantine, n.º 62 (3 de septiembre de 2016): 133–42. http://dx.doi.org/10.36495/1606-9773.2016.62.133-142.

Texto completo

Resumen

Various crops and long-term plantings in Ukraine (Zhytomyr, Kiev, Chernihiv, Khmelnytskyi and Vinnytsia Regions) have been observed for the purpose of identification of the natural centers of entomopathogenic nematodes (EPN) of the genera Steinernema and Heterorhabditis (Nematoda: Rhabditida) — the natural regulators of the number of harmful insects. The reasons and conditions, determining the nature of EPN distribution have been analyzed (Steinernema, Heterorhabditis). The results of the nematologic analysis of 206 soil samples (and traps) had showed that 27 (13.1%) among them turned out to be positive concerning EPN. The conducted examinations of garden and field biocenoses have showed that they are occupied by entomopathogenic nematodes unevenly. On identification frequency, representatives steinernematidae representatives prevailed over heterorhabditis nematodes (55.6% against 44.4%).

Los estilos APA, Harvard, Vancouver, ISO, etc.

25

Kovtun, A. M. "Entomonematologic studies of the agrocenoses of Ukraine as a source of identification of the factors of the potential biocontrol of plant insects". Interdepartmental Thematic Scientific Collection of Plant Protection and Quarantine, n.º 62 (3 de septiembre de 2016): 340–49. http://dx.doi.org/10.36495/1606-9773.2016.62.340-349.

Texto completo

Resumen

Various crops and long-term plantings in Ukraine (Zhytomyr, Kiev, Chernihiv, Khmelnytskyi and Vinnytsia Regions) have been observed for the purpose of identification of the natural centers of entomopathogenic nematodes (EPN) of the genera Steinernema and Heterorhabditis (Nematoda: Rhabditida) — the natural regulators of the number of harmful insects. The reasons and conditions, determining the nature of EPN distribution have been analyzed (Steinernema, Heterorhabditis). The results of the nematologic analysis of 206 soil samples (and traps) had showed that 27 (13.1%) among them turned out to be positive concerning EPN. The conducted examinations of garden and field biocenoses have showed that they are occupied by entomopathogenic nematodes unevenly. On identification frequency, representatives steinernematidae representatives prevailed over heterorhabditis nematodes (55.6% against 44.4%).

Los estilos APA, Harvard, Vancouver, ISO, etc.

26

Qiu, Xuehong, Richou Han, Xun Yan, Mingxing Liu, Li Cao, Toyoshi Yoshiga y Eizo Kondo. "Identification and Characterization of a Novel Gene Involved in the trans-Specific Nematicidal Activity of Photorhabdus luminescens LN2". Applied and Environmental Microbiology 75, n.º 12 (17 de abril de 2009): 4221–23. http://dx.doi.org/10.1128/aem.02967-08.

Texto completo

Resumen

ABSTRACT Photorhabdus luminescens subsp. akhurstii LN2 from Heterorhabditis indica LN2 showed nematicidal activity against axenic Heterorhabditis bacteriophora H06 infective juveniles (IJs). Transposon mutagenesis identified an LN2 mutant that supports the growth of H06 nematodes. Tn5 disrupted the namA gene, encoding a novel 364-residue protein and involving the nematicidal activity. The green fluorescent protein-labeled namA mutant was unable to colonize the intestines of H06 IJs.

Los estilos APA, Harvard, Vancouver, ISO, etc.

27

RANA, AASHA, AASHAQ HUSSAIN BHAT, ASHOK KUMAR CHAUBEY, EBRAHIM SHOKOOHI y RICARDO A. R. MACHADO. "Morphological and molecular characterization of Heterorhabditis bacteriophora isolated from Indian soils and their biocontrol potential". Zootaxa 4878, n.º 1 (12 de noviembre de 2020): 77–102. http://dx.doi.org/10.11646/zootaxa.4878.1.3.

Texto completo

Resumen

Agricultural soils and open fields from Western Uttar Pradesh (India) were surveyed to determine the presence of entomopathogenic nematodes. From the entomopathogenic nematodes isolated, Heterorhabditis isolates were selected and further characterized using morphological, morphometrical and molecular approaches. The results showed that three isolated nematodes were Heterorhabditis bacteriophora and were associated with Photorhabdus laumondii subsp. clarkei bacteria, while the rests were identified as Heterorhabditis indica. The biocontrol potential of H. bacteriophora against three agricultural pests was evaluated. Nematode infectivity experiments showed that the nematode isolates DH7 and DH8 were highly pathogenic against cotton bollworm (Helicoverpa armigera) and tobacco cutworm (Spodoptera litura), and less pathogenic against white grub (Holotrichia serrata) larvae. This study sets the basis for establishing new biocontrol agents to be used in pest management programs in India.

Los estilos APA, Harvard, Vancouver, ISO, etc.

28

Leal, Luís Carlos de Souza Rodrigues, Caio Márcio de Oliveira Monteiro, Alessandra Ésther de Mendonça, Vânia Rita Elias Pinheiro Bittencourt y Avelino José Bittencourt. "Potential of entomopathogenic nematodes of the genus Heterorhabditis for the control of Stomoxys calcitrans (Diptera: Muscidae)". Revista Brasileira de Parasitologia Veterinária 26, n.º 4 (9 de noviembre de 2017): 451–56. http://dx.doi.org/10.1590/s1984-29612017065.

Texto completo

Resumen

Abstract The present study verified the pathogenic potential of entomopathogenic nematodes (EPNs) of the genus Heterorhabditis (Heterorhabditis bacteriophora, isolate HP88 and Heterorhabditis baujardi isolate LPP7) to immature stages of Stomoxys calcitrans in the laboratory. All EPN concentrations of the H. bacteriophora HP88 strain caused mean larval mortality greater than 90% after four days. Higher concentrations of the H. baujardi LPP7 isolate (≥50 EPNs/larva) eliminated more than 70% of larvae after six days with the concentration 200 EPNs/larva reaching mortality levels of 93.3%. The larval mortality at all concentrations of EPNs (25, 50, 100, 150, and 200 EPNs/larva) for both strains was significant (p<0.05) when compared to the respective control groups. Concentrations of H. bacteriophora HP88 yielded an LC50 of 0.36 EPN/larva and LC90 of 29.1; while H. baujardi LPP7 yielded an LC50 of 39.85 and LC90 of 239.18. H. bacteriophora HP88 provided greater inhibition of the emergence of adults when compared to the response obtained with H. baujardi LPP7. EPNs did not cause considerable mortality when applied directly to pupae. The set of observed results suggests that the EPNs of the genus Heterorhabditis, isolates HP88 and LPP7, are a promising alternative in the control of the stable fly.

Los estilos APA, Harvard, Vancouver, ISO, etc.

29

Susurluk, Alper, Urs Wyss, Ralf-Udo Ehlers, Olaf Strauch, Erko Stackebrandt y Ilona Dix. "Identification and ecological characterisation of three entomopathogenic nematode-bacterium complexes from Turkey". Nematology 3, n.º 8 (2001): 833–41. http://dx.doi.org/10.1163/156854101753625326.

Texto completo

Resumen

AbstractTwo heterorhabditid nematode strains (TUR-H1 and TUR-H2), and their bacterial symbionts isolated from soil samples taken at the campus of the Agriculture Faculty of the University of Ankara, Turkey, were identified by molecular methods and by cross-breeding with Heterorhabditis bacteriophora. The bacterial symbionts shared >99% similarity in the 16S rDNA sequence with Photorhabdus luminescens subsp. laumondii. Results of the restriction fragment length analysis of the ITS region assigned both nematode strains to the species H. bacteriophora. Cross-breeding confirmed the species designation for strain TUR-H2. Crosses of TUR-H1 with a hybrid strain of H. bacteriophora or with TUR-H2 resulted in infertile offspring. Both strains reproduced in monoxenic cultures of the symbionts P.luminescens isolated from H. bacteriophora and H. megidis and the resulting dauer juveniles retained cells of the bacteria. Reproduction on the symbionts isolated from H. indica failed. Infectivity at variable soil moisture and heat tolerance of the two heterorhabditid strains was compared with a Turkish isolate of Steinernema feltiae. Significantly more nematodes invaded the insect Galleria mellonella in a sandy soil assay at 10% water content than at lower values. A higher water content significantly reduced the invasion rate. Steinernema feltiae was better adapted to a temperature of 32°C than the heterorhabditid strains. Hardly any nematodes of all strains survived for longer than 4 h at 36°C.

Los estilos APA, Harvard, Vancouver, ISO, etc.

30

Baimey, Hugues, Lionel Zadji, Leonard Afouda, Maurice Moens y Wilfrida Decraemer. "Influence of pesticides, soil temperature and moisture on entomopathogenic nematodes from southern Benin and control of underground termite nest populations". Nematology 17, n.º 9 (2015): 1057–69. http://dx.doi.org/10.1163/15685411-00002923.

Texto completo

Resumen

The influence of three pesticides on the viability and infectivity of four Beninese isolates of entomopathogenic nematodes (EPN), Heterorhabditis indica Ayogbe1, H. sonorensis Azohoue2, H. sonorensis Ze3, and Steinernema sp. Bembereke, was determined. The impact of both soil temperature and soil moisture on the virulence of these EPN to Trinervitermes occidentalis was investigated in laboratory assays. The effect of EPN-infected Galleria mellonella larvae on underground populations of Macrotermes bellicosus was also examined. All tested Heterorhabditis species were more tolerant to glyphosate and fipronil than the Steinernema species. Heterorhabditis sonorensis Azohoue2, showed the best results with 63.2% termite mortality at a soil temperature of 35°C. The increase of soil moisture to 20% (w/w) did not negatively influence the virulence of tested EPN. The underground populations of 71% or 60% treated nests were controlled by H. sonorensis Azohoue2- or H. indica Ayogbe1-infected G. mellonella larvae, respectively.

Los estilos APA, Harvard, Vancouver, ISO, etc.

31

Abate, Birhan A., Bernard Slippers, Michael J. Wingfield, Antoinette P. Malan y Brett P. Hurley. "Diversity of entomopathogenic nematodes and their symbiotic bacteria in south African plantations and indigenous forests". Nematology 20, n.º 4 (2018): 355–71. http://dx.doi.org/10.1163/15685411-00003144.

Texto completo

Resumen

Summary The occurrence and diversity of entomopathogenic nematodes (EPN) and their symbiotic bacteria was evaluated in commercial forestry plantations (Eucalyptus spp., Pinus spp. and Acacia mearnsii) and indigenous forests in South Africa. EPN were most prevalent in A. mearnsii plantations, accounting for 60.7% of the isolates, while indigenous forests, plantations of Pinus spp. and Eucalyptus spp. accounted for 35.7, 3.6 and 0% of the isolates, respectively. DNA sequences of the internal transcribed spacer (ITS) and D2-D3 28S rDNA regions were used to identify the nematode species. Four Steinernema spp. were identified, including S. citrae, S. sacchari, two undescribed species, as well as Heterorhabditis bacteriophora and H. baujardi. Heterorhabditis baujardi is reported from South Africa for the first time. Analysis of 16S rRNA of the bacteria confirmed the presence of at least three Xenorhabdus species from Steinernema isolates and two subspecies of Photorhabdus luminescens from Heterorhabditis species.

Los estilos APA, Harvard, Vancouver, ISO, etc.

32

Chaerani, Chaerani, Y. Suryadi, T. P. Priyatno, D. Koswanudin, U. Rahmat, Sujatmo Sujatmo, Yusuf Yusuf y C. T. Griffin. "ISOLASI NEMATODA PATOGEN SERANGGA STEINERNEMA DAN HETERORHABDITIS". Jurnal Hama dan Penyakit Tumbuhan Tropika 7, n.º 1 (4 de marzo de 2007): 1–9. http://dx.doi.org/10.23960/j.hptt.171-9.

Texto completo

Resumen

Isolation of Entomopathogenic Nematodes Steinernema and Heterorhabditis. Entomopathogenic nematodes from the genus Steinernema and Heterorhabditis (Rhabditida: Steinernematidae and Heterorhabditidae) are promising biological control agent of insect pests. Indigenous nematodes have been isolated and collected for the use in local biological control program of important insect pests. The nematodes were isolated using soil baiting method with insect larvae. Laboratory tests have shown that the mealworm larvae Tenebrio molitor (Coleoptera: Tenebrionidae) served as a good alternative to the standard insect bait, the greater wax moth larvae Galleria mellonella (Lepidoptera: Galleriidae) for isolation and maintenance of nematodes. Both nematodes were successfully isolated using T. molitor larvae from 13% soil samples (26 out of a total of 207) collected from 14 locations in West and Central Java and Lampung provinces in the period of 1993 until 2006. Heterorhabditis (9%) was more prevalent than Steinernema (4%). Both nematodes were successfully propagated on mealworm larvae.

Los estilos APA, Harvard, Vancouver, ISO, etc.

33

Menti, Hara, Mavji Patel, Denis Wright y Roland Perry. "Lipid utilisation during storage of the entomopathogenic nematodes Steinernema feltiae and Heterorhabditis megidis from Greece and the UK". Nematology 5, n.º 1 (2003): 31–37. http://dx.doi.org/10.1163/156854102765216669.

Texto completo

Resumen

Abstract The total lipid (TL) content and the fatty acid composition of the different lipid classes in infective juveniles of Steinernema feltiae and Heterorhabditis megidis isolates from Greece (GR) and from the United Kingdom (UK) were compared, and the changes during storage were determined. Steinernema feltiae GR had a greater amount of TL than S. feltiae UK, which was reflected in a greater neutral lipid (NL) content. The phospholipid and free fatty acid fractions of the two Steinernema populations were similar. The two Heterorhabditis populations did not differ in their lipid content. In both S. feltiae populations, NL decreased by ca 60% during the first 4 weeks but remained more or less stable during the next 16 weeks. In the two Heterorhabditis populations, NL decreased by ca 70% during the first 4 weeks and continued to decrease, with 3-5% remaining after 12 weeks. The fatty acid profiles and the percentages of saturation of NL and phospholipid fractions in each population were similar before and after storage.

Los estilos APA, Harvard, Vancouver, ISO, etc.

34

Sigareva, D. D., А. М. Kovtun y V. V. Kornyushin. "Occurrence of Entomopathogenic Nematodes (Rhabditida: Steienernematidae, Heterorhabditidae) from Agricultural Ecosystems in Forest (Polissya) and Forest-Steppe Natural Zones of Ukraine". Vestnik Zoologii 53, n.º 4 (1 de agosto de 2019): 285–96. http://dx.doi.org/10.2478/vzoo-2019-0028.

Texto completo

Resumen

Abstract A survey for entomopathogenic nematodes (EPNs) of the Steienernematidae and Heterorhabditidae in soils of different crop types of agricultural lands (household plots, commercial fields) in the forest (Polissya) and forest-steppe (Lisostep) zones of Ukraine was carried out in spring, summer and autumn months from 2016 to 2018. In total, 205 soil samples and 92 live-traps were processed. In addition, 98 samples of soil-living larvae and adults of insect crop pests, including cockchafer beetles, click beetle larvae, darkling beetle larvae, caterpillars of the scoops were collected. It is shown that the EPNs distribution and frequency of occurrence depends on the natural geographical features (regional characteristics) and habitat types. EPNs were found in 46 (15.4 %) out 297 samples. The incidence (% of samples) of the entomopathogenic nematodes, and their diversity varied depending on the location-based sampling, the type of agrocenosis, and the predominant agricultural plant species or typical species-edificators. The proportion of entomopathogenic nematodes (Steinernema spp., Heterorhabditis spp.) recovery from regions of Lisostep zone was 16.9 %, and 13.6 % from regions of Polissya zone. The highest number among all positive samples was recorded from the apple trees, Malus domestica Borkh., 1803 (10 samples). The least number of positive samples (one sample) was obtained from sweet cherry trees, Prúnus cérasus L., 1753, junipers, Juniperus communis L., 1753, alfalfa, Medicago sativa L., 1753, common beans, Phaseolus vulgaris L., 1753, and common pumpkin, Cucurbita pepo L., 1753. The steinernematid nematodes were noticeably dominant over heterorhabditid nematodes: 60.8 % vs 39.2 % respectively. Steinernema spp. is widespread in different regions and plots, whereas Heterorhabditis spp. are common in fruit orchards and coniferous decorative perennial plantings.

Los estilos APA, Harvard, Vancouver, ISO, etc.

35

Parada Domínguez, Oscar, Raquel Alatorre Rosas, Ariel Wilbert Guzmán Franco, Francisco Hernández Rosas, Luz Irene Rojas Avelizapa y Víctor Manuel Ruíz Vera. "Efecto de nematodos entomopatógenos en ninfas de Aeneolamia albofasciata y su persistencia en suelos cañeros de Veracruz". Revista Mexicana de Ciencias Agrícolas, n.º 22 (3 de abril de 2019): 115–27. http://dx.doi.org/10.29312/remexca.v0i22.1863.

Texto completo

Resumen

El objetivo de este estudio fue evaluar la patogenicidad de los nematodos, Heterorhabditis sp. (CPVG13) y Steinernema spp. (CPVC12, CPVC13) sobre el salivazo, Aeneolamia albofasciata y determinar su persistencia en el suelo de tres ingenios azucareros Potrero, Constancia y Motzorongo, del estado de Veracruz. En el primer experimento la patogenicidad de los nematodos entomopatógenos se evaluó en ninfas de mosca pinta, A. albofasciata de 3° y 4° instar, se aplicaron 120 (juveniles infectivos) JI/ninfa sobre cajas con seis cavidades, cubiertas previamente con papel filtro, cada cavidad contenía un estolón de pasto (Cynodon sp.) y una ninfa por cavidad. En el segundo experimento, se evaluó la persistencia de los nematodos entomopatógenos (NEPs) en suelo, el experimento tuvo una duración de 70 días, con evaluaciones semanales independientes, de 32 unidades experimentales por semana. El experimento de patogenicidad revelo que ambos nematodos fueron capaces de atravesar la saliva que protege a las ninfas, matar y desarrollarse en los cadáveres produciendo nueva progenie de JI. La mortalidad más alta (62.5%) se observó con Heterorhabditis (CPVG13), produciendo además la mayor concentración de JI por ninfa (3500JI/ninfa). Se encontraron diferencias significativas entre los perfiles de persistencia entre Heterorhabditis (CPVG13) y Steinernema (CPVC12). Se encontró un efecto significativo del suelo en la supervivencia de ambos nematodos. El aislamiento que persistió más en suelo fue el Steinernema comparado con el de Heterorhabditis (CPVG13). Profundizar en estos estudios, permitirá determinar el impacto de la interacción entre salivazo-NEPs y el suelo.

Los estilos APA, Harvard, Vancouver, ISO, etc.

36

Batista, E. S. de P., A. M. Auad, M. P. Frias y C. M. de O. Monteiro. "NEMATOIDES ENTOMOPATOGÊNICOS INFECTAM OVOS E ADULTOS CIGARRINHA-DAS-PASTAGENS?" Arquivos do Instituto Biológico 78, n.º 3 (septiembre de 2011): 475–78. http://dx.doi.org/10.1590/1808-1657v78p4752011.

Texto completo

Resumen

RESUMO Nematoides entomopatogênicos (NEPs) são potenciais controladores biológicos das ninfas de cigarrinhas-das-pastagens. Com o objetivo de avaliar a eficiência dos NEPs contra as demais fases de vida (ovos e adultos) de Mahanarva spectabilis, desenvolveu-se experimento sob condições de laboratório. Ovos em diferentes fases de desenvolvimento embrionário foram expostos aos NEPs Steinernema anomali. S. carpocapsae. S. feltiae. S. riobrave. Heterorhabditis amazonensis RSC1, H. amazonensis RSC5, Heterorhabditis sp. JPM3, Heterorhabditis indica LPP1 e Heterorhabditis sp. PI no volume de 2 mL com concentração de 2.000 JIs/mL. A eficiência do patógeno foi avaliada através da dissecação dos ovos após sete dias de exposição. No experimento com adultos as unidades experimentais (UEs) consistiram de gaiolas contendo adultos da cigarrinha submetidas a uma suspensão aquosa com 20 mL contendo 8.000 JIs/mL de S. riobrave (tratamento) das quais se compararam a mortalidade e número de ovos recuperados com os mesmos parâmetros das UEs livres de nematoides (testemunha). Os nematoides não foram capazes de penetrar os ovos do cercopídeo. Não foi observada morte de indivíduos adultos de cigarrinha, tampouco se observou redução no número de ovos entre as UEs tratadas e testemunhas. Não houve influência da presença de nematoides sobre a freqüência de adultos que permaneciam sobre o substrato. Não foi caracterizada vulnerabilidade destas fases de desenvolvimento do inseto às espécies testadas desses patógenos, portanto, não devem ser aplicados visando o controle dessas fases de desenvolvimento do inseto.

Los estilos APA, Harvard, Vancouver, ISO, etc.

37

Libardoni, Gabriela, Raiza Abati, Amanda Roberta Sampaio, Fernanda Caroline Colombo, Rodrigo Mendes Antunes Maciel, Bruna Guide, Fabiana Martins Costa-Maia, Everton Ricardi Lozano, Pedro Manuel Oliveira Janeiro Neves y Michele Potrich. "Impact of entomopathogenic nematodes on Africanized honey bees Apis mellifera L. (Hymenoptera: Apidae) workers". Semina: Ciências Agrárias 41, n.º 6supl2 (6 de noviembre de 2020): 3441–48. http://dx.doi.org/10.5433/1679-0359.2020v41n6supl2p3441.

Texto completo

Resumen

Africanized honey bee populations (Apis mellifera L.) have been decreasing mainly due to the intense use of synthetic insecticides associated with pollution and climate change. To minimize these impacts on the environment and bee populations, the use of biological control agents has been intensified. These products are generally safer for non-target insects, such as bees, which are important pollinating insects. Thus, the objective of this study was to evaluate the impact of entomopathogenic nematodes on the longevity of the Africanized honey bee A. mellifera workers. Seven treatments were used: Heterorhabditis amazonensis, Heterorhabditis bacteriophora, Heterorhabditis indica, Steinernema carpocapsae, Steinernema feltiae, and Steinernema rarum, at a concentration of 40 infective juveniles per cm2 (IJs/cm²), and a control in which autoclaved distilled water was used. Two bioassays were performed: 1) spraying nematodes on the workers and 2) spraying nematodes on glass plates, in which the bees remained for two hours. Each treatment consisted of five replicates with 20 bees each. Bees were kept in cages of PVC (20 × 10 cm) covered with a voile fabric and provided pieces of cotton soaked in water and Candy paste. The cages were kept in a climatized room (27 ± 2 °C temperature, 60 ± 10% relative humidity, and 12 h photophase) and the mortality was evaluated from 12 to 240 hours. In bioassay 1, the three treatments with nematodes of the genus Steinernema reduced the longevity of the workers (103.9, 96.3, and 99.6 h) when compared to treatments with Heterorhabditis (149.7, 126.8, and 134.7 h), of which, only H. amazonensis (149.7 h) did not differ from the control (166.0 h). In bioassay 2, all treatments reduced the longevity of honey bees (155.4 to 93.9 h) in relation to the control (176.1 h). Entomopathogenic nematodes, especially Heterorhabditis, need to be tested using other methodologies and for different durations of exposure and application because in the laboratory, they were less selective to A. mellifera.

Los estilos APA, Harvard, Vancouver, ISO, etc.

38

Sturhan, Dieter y Marta Liskova. "Occurrence and distribution of entomopathogenic nematodes in the Slovak Republic". Nematology 1, n.º 3 (1999): 273–77. http://dx.doi.org/10.1163/156854199508261.

Texto completo

Resumen

AbstractInfective-stage juveniles of entomopathogenic nematodes of the genera Steinernema and Heterorhabditis were recovered by direct extraction from 36% of a total of 111 soil samples collected in various biotopes from different regions of Slovakia. The rate of prevalence was highest in forest soil (58%). On the basis of morphological characters of the infective juveniles eight Steinernema and one Heterorhabditis species were distinguished. Steinernema affine, S. intermedium and S. feltiae were most prevalent (together 74% of all records). The other species of Steinernema encountered were S. kraussei, S. carpocapsae, S. bicornutum, a species of the S. glaseri group and an undescribed species earlier recorded from Germany. In 11 of the 40 soil samples positive for entomopathogenic nematodes mixtures of two to four species were present. Several species showed a distinct habitat preference, e.g., S. affine for arable soil and S. intermedium for woodland and river bank vegetation with trees. A preference for certain soil types was less apparent. Untersuchungen uber Vorkommen und Verbreitung entomopathogener Nematoden in der Slowakischen Republik - Insgesamt 111 Bodenproben, die in unterschiedlichen Biotopen aus verschiedenen Regionen der Slowakei entnommen worden waren, wurden auf entomopathogene Nematoden untersucht. Infektionsjuvenile der Gattungen Steinernema und Heterorhabditis waren uber eine direkte Extraktion der Nematoden aus dem Boden in 36% aller Proben nachweisbar. Der hochste Anteil "positiver" Proben fand sich bei Proben aus Waldern (58%). Anhand morphologischer Merkmale der Infektionsjuvenilen waren acht Steinernema Arten und eine Heterorhabditis-Art differenzierbar. Steinernema affine, S. intermedium und S. feltiae waren die haufigsten Arten (insgesamt 74% aller Nachweise). S. kraussei, S. carpocapsae, S. bicornutum, eine Steinernema-Art der S. glaseri-Gruppe und eine noch unbeschriebene Steinernema-Art (bereits aus Deutschland bekannt) und Heterorhabditis sp. wurden seltener gefunden. In 11 aller 40 "positiven" Proben kamen zwei bis vier Arten nebeneinander vor. Einige der Arten zeigten eine deutliche Bevorzugung bestimmter Biotoptypen, so S. affine von Acker- und Gartenboden und S. intermedium von Waldern und Ufervegetation mit Baumen. Eine Bevorzugung bestimmter Bodenarten war dagegen kaum erkennbar.

Los estilos APA, Harvard, Vancouver, ISO, etc.

39

Johnigk, Stefan-Andreas y Ralf-Udo Ehlers. "Endotokia matricida in hermaphrodites of Heterorhabditis spp. and the effect of the food supply". Nematology 1, n.º 7 (1999): 717–26. http://dx.doi.org/10.1163/156854199508748.

Texto completo

Resumen

AbstractIntra-uterine birth causing maternal death (endotokia matricida) is relatively common in rhabditid nematodes and typical for entomopathogenic nematodes of the genus Heterorhabditis. A detailed description of this phenomenon is given, including a summary of embryo development, egg-laying, juvenile hatching and development. It is demonstrated that low food supply significantly promotes the beginning of endotokia matricida but has no influence on the time scale of the process. The biological function of endotokia matricida and the intra-uterine induction of the dauer formation is discussed. Endotokia matricida in Heterorhabditis spp. is a well synchronised process of the destruction of the maternal tissues correlated with the juvenile development including the uptake of the symbiotic bacteria by the late pre-dauer stage. It secures the development of dauer juveniles at a moment when the external food supply is reducing and provides offspring which are well equipped with energy reserves and symbiotic bacteria for long term survival and subsequent infection of insects in the soil. Endotokia matricida bei Hermaphroditen von Heterorhabditis spp. und der Einfluss der Nahrungsversorgung . - Der Schlupf juveniler Nematoden im mutterlichen Uterus mit anschliessender Totung des Muttertieres (endotokia matricida) ist relativ weit verbreitet bei rhabditiden Nematoden und typisch fur entomopathogene Nematoden der Gattung Heterorhabditis. Die Endotokia matricida wird beschrieben sowie die Embryonalentwicklung, das Eilegeverhalten, der Schlupf und die Entwicklung der Juvenilen. Der Beginn der endotokia matricida wird durch eine niedrige Nahrungsverfugbarkeit in der Kultur signifikant gefordert, diese hat jedoch keinen Einfluss auf den zeitlichen Ablauf der endotokia matricida. Die biologische Funktion der endotokia matricida und die intra-uterine Induktion der Dauerlarvenbildung werden diskutiert. Die endotokia matricida bei Heterorhabditis spp. ist ein gut synchronisierter Prozess, bei dem die Zerstorung des Muttertiers korreliert mit der Entwicklung der Juvenilstadien, einschliesslich der Aufnahme der symbiotischen Bakterien durch das Pra-Dauer Stadium. Sie sichert die Entwicklung von Dauerlarven zu einem Zeitpunkt, wenn die externe Nahrungsversorgung sich verschlechtert und bringt so Nachkommen hervor, die gut mit Energiereserven und symbiotischen Bakterien ausgestattet sind, um im Boden lange zu uberdauern und Insekten zu befallen.

Los estilos APA, Harvard, Vancouver, ISO, etc.

40

WIRATNO, WIRATNO y ROHIMATUN ROHIMATUN. "PATOGENISITAS NEMATODA Heterorhabditis sp. TERHADAP KUMBANG DAUN KELAPA Brontispa longissima GESTRO". Jurnal Penelitian Tanaman Industri 18, n.º 4 (19 de junio de 2020): 137. http://dx.doi.org/10.21082/jlittri.v18n4.2012.137-142.

Texto completo

Resumen

ABSTRAK Suatu bioassay telah dilakukan di Balai Penelitian Tanaman Rempah dan Obat Bogor, dari bulan November 2010 sampai dengan Maret 2011, yang bertujuan untuk mengetahui potensi Heterorhabditis sp. dalam mengendalikan Brontispa longissima. Nematoda dipanen dengan cara meletakkan larva Tenebrio molitor mati terinfeksi nematoda patogen serangga (NPS) di atas kertas saring yang diletakkan di dalam cawan petri berisi 30 ml air. Juvenil infektif (JI) yang ada di dalam tubuh larva akan keluar dan hidup di dalam air. Suspensi JI kemudian dilarutkan 1.000 kali lalu populasinya dihitung di bawah mikroskop binokuler dan diulang 3 kali. Populasi JI diperoleh dengan melarutkan 10 ml suspensi dengan sejumlah air sehingga diperoleh populasi 7.000, 3.500, 1.750, 875, 438, dan 0 JI/ml air. Masing-masing perlakuan diujikan pada 10 ekor larva, pupa, dan imago dengan menyemprotkan 2 ml suspensi JI. Pengamatan mortalitas B. longissima dilakukan pada 24, 48, dan 72 jam setelah infestasi (JSI). Hasil penelitian menunjukkan bahwa patogenisitas Heterorhabditis sp. tertinggi pada stadia larva diikuti imago dan pupa. Pada populasi 3.500 JI/ml air kematian larva, imago, dan pupa pada 24 JSI berturut-turut sekitar 73, 63, dan 10%, berbeda tidak nyata dengan perlakuan 7.000 JI/ml air. LC 50 Heterorhabditis sp. terhadap larva, imago, dan pupa pada 72 JSI berturut-turut 1.492, 2.622, dan 800.818 JI/ml air. Kata kunci: Brontispa longissima, kelapa, Heterorhabditis sp., patogenisitasABSTRACT In order to evaluate the potensial of Heterorhabditis sp. in controlling B. longissima bioassays was conducted in Indonesian Research Institute for Spices and Medicinal Crops, Bogor from November 2010 until March 2011. Infective juveniles (IJ) of the nematodes were harvested by putting dead Tenebrio molitor on a filter paper placed in a petri dish containing 30 ml of water. IJs in the larval body will then go out and live in the water. The suspension was then diluted 1,000 times and then population counted under a binocular microscope and repeated 3 times. IJ population is obtained by dissolving 10 ml suspension to obtain 7,000; 3,500; 1,750; 875; 438; and 0 IJs/ml of water. Each treatment was tested on 10 larvae, pupae, and adults by spraying 2 ml IJ suspension. Mortality observations were made at 24, 48, and 72 hours after infestation (HAI). The results showed that the highest Heterorhabditis sp. pathogenicity was found in larvae stadium followed by pupae and adult stadia. In the 3,500 IJ population/ml of water, larvae, imago, and pupae mortalities in 24 HAI were approximately 73, 63, and 10%, respectively and were not significantly different with 7,000 IJ/ml of water. LC 50 values of Heterorhabditis sp. on the larvae, adult, and pupae in 72 HAI were 1,492; 2,622; and 800,818 IJ/ml of water, respectively. Key words: Brontispa longissima, Cocos nucifera, Heterorhabditis sp., pathogenicity

Los estilos APA, Harvard, Vancouver, ISO, etc.

41

Rutherford, T. A., D. Trotter y J. M. Webster. "THE POTENTIAL OF HETERORHABDITID NEMATODES AS CONTROL AGENTS OF ROOT WEEVILS". Canadian Entomologist 119, n.º 1 (enero de 1987): 67–73. http://dx.doi.org/10.4039/ent11967-1.

Texto completo

Resumen

AbstractGreenhouse and field trials were done to determine the potential of Heterorhabditis heliothidis (Khan, Brooks and Hirschmann) Poinar (NC19 strain), an undescribed Heterorhabditis sp. (NC447 strain), and Steinernema feltiae Filipjev (A32−6 strain) to control British Columbia populations of black vine weevil (Otiorhyncus sulcatus Fab.) and strawberry root weevil (O. ovatus L.). An outdoor application of H. heliothidis applied at rates of 500 and 5000 nematodes per litre of soil gave significantly better control of black vine weevil larvae on potted, lodgepole pine trees (Pinus contorta Dougl.) than did a diazinon drench. Under greenhouse conditions Heterorhabditis sp. NC447 was the most effective nematode of the three tested against O. ovatus on potted, Douglas-fir seedlings (Pseudotsuga menziesii (Mirb.) Franco) and S. feltiae the least effective, at all dose rates tested. A field trial using H. heliothidis against O. ovatus in a forest nursery did not provide a significant degree of weevil control. This lack of control is attributed to the average outdoor temperature (11 °C) during the treatment period, which was below the nematode’s optimum temperature range, and the higher-than-average rainfall.

Los estilos APA, Harvard, Vancouver, ISO, etc.

42

GRENIER, E., F. M. CATZEFLIS y P. ABAD. "Genome sizes of the entomopathogenic nematodes Steinernema carpocapsae and Heterorhabditis bacteriophora (Nematoda: Rhabditida)". Parasitology 114, n.º 5 (mayo de 1997): 497–501. http://dx.doi.org/10.1017/s0031182096008736.

Texto completo

Resumen

There is currently no information on the genome size and complexity in the entomoparasitic nematodes Steinernema and Heterorhabditis. DNA reassociation kinetics were used to determine the genome size and complexity in 2 species: Steinernema carpocapsae and Heterorhabditis bacteriophora. C0t curves derived from renaturation kinetics of denatured DNA indicate that the genomes of these entomoparasitic rhabditids are different both in size and complexity. Genome sizes were estimated at 2·3 × 108 bp for S. carpocapsae and 3·9 × 107 bp for H. bacteriophora and repetitive DNA contents were found to represent 39% and 51% of these respective genomes.

Los estilos APA, Harvard, Vancouver, ISO, etc.

43

Morris, O. N., V. Converse y J. Harding. "VIRULENCE OF ENTOMOPATHOGENIC NEMATODE–BACTERIA COMPLEXES FOR LARVAE OF NOCTUIDS, A GEOMETRID, AND A PYRALID". Canadian Entomologist 122, n.º 2 (abril de 1990): 309–19. http://dx.doi.org/10.4039/ent122309-3.

Texto completo

Resumen

AbstractNine entomopathogenic nematode–bacteria complexes were screened for their virulence against larvae of six noctuids, a geometrid, and a pyralid. Ninety-six-hour LD50’s of steinernematids (and heterorhabditids) ranged from 1 to 3 (1–8) infective juveniles in Galleria mellonella (L.), 1–71 (2) in Peridroma soucia (Hbn.), 1–10 (1–3) in Mamestra configurata (Wlk.), 1–28 (3–7) in Euxoa ochrogaster (Gn.), 19 in Lacanobia radix (Wlk.), 22–60 (4) in Pseudaletia unipuncta (Haw.), 2–95 (111) in Agrotis ipsilon (Hufn.), and 3–28 in Paleacrita vernata (Peck). The nematode, Steinernema feltiae LIC, a cold-hardy strain isolated in Newfoundland, was highly virulent for G. mellonella and M. configurata, but not for P. soucia and E. ochrogaster. The number of nematodes invading larvae and the number produced were greater in G. mellonella than in other insects tested. Nematode–bacteria complexes that showed potential for controlling cutworms included S. feltiae, S. glaseri, S. bibionis, Heterorhabditis bacteriophora, and H. heliothidis.

Los estilos APA, Harvard, Vancouver, ISO, etc.

44

DEMPSEY, C. M. y C. T. GRIFFIN. "Phased activity in Heterorhabditis megidis infective juveniles". Parasitology 124, n.º 6 (junio de 2002): 605–13. http://dx.doi.org/10.1017/s0031182002001609.

Texto completo

Resumen

The infectivity of Heterorhabditis megidis infective juveniles (IJs) increases during storage in water. We investigated whether this change can be related to other features of the IJs' behaviour. IJs were stored in water for 4 weeks at 20 °C, and the following parameters were assessed at intervals: infectivity for Galleria mellonella, dispersal in sand, host-finding on agar, and the percentage of IJs active in water. In addition, the behaviour of the IJs in water was described using 7 categories. Immediately after emerging from the host cadaver, IJs were highly active (99% of IJs in water were active and 65% displayed ‘waving’, the normal method of forward movement). Maximum responsiveness to host volatiles in an agar plate assay was recorded on day 2 (69% of IJs moved from the point of application and 44% of all IJs in the agar arena moved towards a host) and maximum dispersal in sand (5·8 cm) on day 0. These tendencies declined gradually with age, while infectivity underwent a significant increase from 11 nematodes per insect on day 0 to 38 nematodes per insect on day 9. Three phases could be distinguished in the behaviour of H. megidis IJs: an initial dispersal phase, during which infectivity was low; an infective phase, during which dispersal tendency was declining, and a third phase during which all behaviours (dispersal, infectivity and activity) were declining. Over the 4-week storage period, infectivity of H. megidis IJs was correlated (R2 = 0·83) with the percentage time IJs engaged in ‘head thrusting’ (a behaviour that resembles penetration). There is no evidence that the observed increase in infectivity of H. megidis strain UK211 could be accounted for by a generally greater level of motor activity, nor by an increase in responsiveness to volatile host cues, and it is suggested that it is due to an increased tendency to attempt penetration.

Los estilos APA, Harvard, Vancouver, ISO, etc.

45

Liu, Jie y Ralph E. Berry. "Heterorhabditis marelatusn. sp. (Rhabditida: Heterorhabditidae) from Oregon". Journal of Invertebrate Pathology 67, n.º 1 (enero de 1996): 48–54. http://dx.doi.org/10.1006/jipa.1996.0008.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

46

Nguyen, Khuong, David Sharpiro-Ilan, Robin Stuart, Clay McCoy, Rosalind James y Byron Adams. "Heterorhabditis mexicana n. sp. (Rhabditida: Heterorhabditidae) from Tamaulipas, Mexico, and morphological studies of the bursa of Heterorhabditis spp." Nematology 6, n.º 2 (2004): 231–44. http://dx.doi.org/10.1163/1568541041218031.

Texto completo

Resumen

Abstract A new species of nematode in the genus Heterorhabditis was found in the northern part of the state of Tamaulipas, Mexico. Morphological and molecular data indicate that this nematode is a new species. The new species is described as Heterorhabditis mexicana n. sp. and is a sister taxon to H. indica. Heterorhabditis mexicana n. sp. is morphologically similar to H. bacteriophora, H. brevicaudis and H. indica and can be distinguished from these species mainly by male and female characters. Of the examined specimens of H. mexicana n. sp., 70% of males have eight pairs of bursal papillae, compared to nine in all other species. The ratio of the gubernaculum to spicule length (GS ratio) is higher than that of H. bacteriophora, H. brevicaudis and H. indica and the length of the spicule relative to anal body width (SW) is lower than all other species. For females, the vulval form of the new species is quite different from that of those species with a similar morphology (i. e ., H. bacteriophora and H. indica) and more closely resembles that of H. zealandica. The new species can also be distinguished from H. megidis, H. zealandica and H. marelatus by the body length, pharynx length of the infective juvenile and D% (distance from anterior end/pharynx length × 100), GS and SW ratios of males. In the ITS region of the rDNA tandem repeating unit, H. mexicana n. sp. has evolved 13 autapomorphic nucleotide character states, differing from its sister taxon H. indica at 113 aligned positions. The morphological and molecular data are sufficient to identify cladogenesis and delimit H. mexicana n. sp. as evolving independently from the other members of the genus.

Los estilos APA, Harvard, Vancouver, ISO, etc.

47

Edgington, Steve, Alan G. Buddie, Dave Moore, Andrés France, Loreto Merino, Lukasz M. Tymo y David J. Hunt. "Diversity and distribution of entomopathogenic nematodes in Chile". Nematology 12, n.º 6 (2010): 915–28. http://dx.doi.org/10.1163/138855410x498897.

Texto completo

Resumen

Abstract A systematic programme of surveys for entomopathogenic nematodes (EPN) was done in Chile between 2006 and 2008. The survey spanned the principal ecosystems of mainland Chile as well as a number of islands, and covered a wide range of habitats including the Atacama Desert, Andean Altiplano, temperate rainforests and subpolar territory. Nearly 1400 soil samples were collected, of which 7% were positive for EPN. Of 101 EPN isolates obtained, 94 were Steinernema spp. and seven were Heterorhabditis sp. Of the 94 Steinernema isolates, 39 were identified as Steinernema feltiae, the remainder being distributed between two new species, S. unicornum (52 records) and S. australe (three records). The Heterorhabditis isolates, all designated as Heterorhabditis sp.1, are referred to herein as H. cf. safricana. Steinernema feltiae and S. unicornum were collected predominately in the south of Chile and were obtained from a range of habitats, including forests, open grassland, montane soils and coastal zones; neither species was recovered from the far north of the country (viz., desert soils in the Norte Grande region). Steinernema australe was found in only three soil samples, all from humid, cool, coastal localities in the south. Heterorhabditis cf. safricana was recovered from the northern regions, with most isolates found in or on the periphery of the Atacama Desert; they were not recovered from cooler, more humid regions of southern Chile. Molecular information indicated there were two subgroups of both S. unicornum and S. feltiae, with a geographical, intraspecific split of subgroups between the most southerly and the more central survey zones. All isolates were collected by ex situ baiting with waxmoth larvae and the natural hosts are unknown.

Los estilos APA, Harvard, Vancouver, ISO, etc.

48

Miduturi, J. S., M. Moens, W. M. Hominick, B. R. Briscoe y A. P. Reid. "Naturally occurring entomopathogenic nematodes in the province of West-Flanders, Belgium". Journal of Helminthology 70, n.º 4 (diciembre de 1996): 319–27. http://dx.doi.org/10.1017/s0022149x00015613.

Texto completo

Resumen

AbstractThe presence of naturally occurring entomopathogenic nematodes (epns) was surveyed in the West-Flanders province in the north-west of Belgium. In 21 sites of different agronomical situations, 130 soil samples were taken. Using the Galleria larva bait technique, 16 soil samples were found positive for epns. Fifteen samples were found to contain Steinernema spp. (nine S.feltiae, five S. affinis, one Steinemema species B3). The remaining positive sample contained Heterorhabditis sp. (North West European strain). The morphometric characters of the isolates were highly variable and did not correspond precisely to the original descriptions; however, biochemical characterization confirmed their identity. The epns were isolated from 50%, 18.8% or 12.3% of the samples taken in sand dunes, grassland or woodlands, respectively. S. feltiae and S. affinis were isolated in these three habitats; Heterorhabditis sp. was found in a grassland habitat. Steinernema feltiae was prevalent in loamy sand soils with a wide range of organic matter content; S. affinis, Heterorhabditis sp. and Steinernema species B3 were isolated in sandy loam soils. All the positive sample sites were in the pH range of 4.0–8.1. This is the first report of naturally occurring entomopathogenic nematodes in Belgium.

Los estilos APA, Harvard, Vancouver, ISO, etc.

49

Bertolotti, María, Gladys De Sousa, Mónica Valenzuela y María M. A. De Doucet. "Analysis of two isolates of a Heterorhabditis bacteriophora population detected in Córdoba, Argentina". Nematology 2, n.º 4 (2000): 473–76. http://dx.doi.org/10.1163/156854100509231.

Texto completo

Resumen

AbstractEntomopathogenic nematodes of the genus Heterorhabditis are associated with symbiotic bacteria Photorhabdus spp. (Enterobacteriaceae). Taxonomic studies confirm that each species of nematode has a specific natural association with only one species of bacterium (Boemare & Doucet, 1996). Except in a few cases, the bacteria change the colour of the parasitized insect to different reddish tones and produce bioluminescence (Grimont et al., 1984; Boemare & Doucet, 1996). These distinct colours would be assumed to be due to the different species of Photorhabdus and, consequently, to indicate different species of Heterorhabditis. Therefore, the colour of the cadaver has been used as a taxonomic character (Stock, 1993). In a single soil sample from Córdoba City, Argentina, two isolates of Heterorhabditis were found that were clearly distinguished by the colour of the parasitized Galleria mellonella larva: isolate A, violet-brown; B, reddish. These different phenotypes led us to suppose that the nematode isolates were associated with different symbiotic bacteria and that the nematodes were different species. The purposes of this work were: to establish the identity of the isolates and to compare them on the basis of morphological and morphometric characters, and isozyme patterns.

Los estilos APA, Harvard, Vancouver, ISO, etc.

50

Leite, Luís G., Laerte A. Machado, Marineide M. Aguillera, Regina C. D. Rodrigues y Aldomário S. Negrisoli Jr. "PATOGENICIDADE DE Steinernema spp. E Heterorhabditis sp. (NEMATODA: RHABDITIDA) À NINFAS DA CIGARRINHA DA RAÍZ DA CANA-DE-AÇUCAR, (Mahanarva fimbriolata)". BRAZILIAN JOURNAL OF AGRICULTURE - Revista de Agricultura 78, n.º 1 (19 de noviembre de 2015): 139. http://dx.doi.org/10.37856/bja.v78i1.1384.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

Artículos de revistas sobre el tema "Heterorhabditis"

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros