TitleAbstractYear(sorted ascending)
susceptibility of the carrot weevil (coleoptera: curculionidae) to steinernema feltiae, s. bibionis, and heterorhabditis heliothidis.larvae, pupae, and adults of the carrot weevil (listronotus oregonensis) were infected and killed by the three entomophagous nematodes (steinernema feltiae, s. bibionis, and heterorhabditis heliothidis) under controlled conditions. third-stage larvae were more susceptible than pupae or adults. s. feltiae and s. bibionis were the most aggressive nematode species, causing larval mortality after 24-48 hours in both continuous and 2-hour contact with nematode suspension. the nematodes multiplied suf ...198519294108
steinernema feltiae (dd-136) and s. glaseri: persistence in soil and bark compost and their influence on native nematodes.infective juveniles (j3) of the entomogenous nematodes steinernema feltiae dd-136 (ca. 10,000 j3/100 ml) and s. glaseri (ca. 2,500 j3/100 ml) were incubated in steam-sterilized and nonsterilized sandy soil and bark compost for 8 weeks at 25 c. the nematodes were recovered by a two-step extraction procedure at 1-week intervals, and their infectivity to lepidopterous larvae (spodoptera litura and galleria mellonella) and their effect on the population and community of native nematodes in soil were ...198619294183
escape of steinernema feltiae from alginate capsules containing tomato seeds.the entomogenous nematode steinernema feltiae was encapsulated in an alginate matrix containing a tomato seed. when these capsules were placed on 0.8% agar for 7 days, the seed germinated and ca. 20% of the nematodes escaped from the capsules, whereas only 0.1% escaped from capsules without seeds. when capsules containing nematodes and a seed were planted into sterilized or nonsterilized soil, nematodes escaped to infect galleria mellonella larvae. when seed in capsules containing ca. 274 nemato ...198719290145
field trials of steinernema feltiae (nematoda: steinernematidae) for control of alphitobius diaperinus (coleoptera: tenebrionidae)in commercial broiler and turkey houses. 19873571698
steinernema feltiae (= neoaplectana carpocapsae): effect of sterols and hypolipidemic agents on development.the structure and concentration of sterol in a lipid-defined artificial medium affected the development of the entomogenous nematode, steinernema feltiae (= neoaplectana carpocapsae). the nematode grew normally in vitro when the medium was supplemented with delta 5-desalkylsterol (cholesterol) or delta 5-desalkylsteryl ester (cholesterol oleate). the minimum amount of cholesterol in the medium that was necessary to support the development of s. feltiae to the climax population (i.e., dauer stage ...19883191959
effect of host age and nematode strain on susceptibility of spodoptera frugiperda to steinernema feltiae.median lethal concentrations (lc) were determined for four nematode populations (two strains of steinernema feltiae, a s. feltiae hybrid, and s. bibionis) against fifth-instar fall armyworm (spodoptera frugiperda) larvae and for the most virulent of these nematodes against different instars and stages of the insect. based on lack of overlap of 95% fiducial limits, there were significant differences in virulence among the four nematodes. the lc ranged from 7.6 to 33.3 nematodes/ 0.7 ml water, and ...198819290189
liquid culture of the entomogenous nematode steinernema feltiae with its bacterial symbiont.the insect-parasitic nematode, steinernema feltiae filipjev strain 42, was reared in liquid culture along with its bacterial symbiont, xenorhabdus nematophilus thomas &poinar. first-stage juveniles developed into reproducing adults in a maintenance salts medium containing resuspended xenorhabdus cells and the yeast kluyveromyces marxianus (hansen) van der walt or cholesterol. cultures with media depths greater than 4 mm required aeration. nematode populations increased as bacterial density incre ...198919287644
biological control of the pecan weevil, curculio caryae (coleoptera: curculionidae), with entomopathogenic nematodes.steinernema carpocapsae (weiser) strain a11, s. feltiae (filipjev) strain sn, and heterorhabditis bacteriophora poinar strains hp88 and georgia were tested for their efficacy as biological control agents of the pecan weevil, curculio caryae (horn), in pecan orchard soil-profile containers under greenhouse conditions. percentage c. caryae parasitism by s. carpocapsae and h. bacteriophora strain hp88 and georgia was consistently poor when applied either prior to or following c. caryae entry into t ...199319279746
survey of heterorhabditidae and steinernematidae (rhabditida, nematoda) in western canada.a survey was done in the summer months along the alaska highway, in other parts of british columbia, in northern alberta, and in the yukon territory for steinernematid and heterorhabditid nematodes occurring in the top 10 cm of soil. steinernema feltiae and steinernema spp. were found at 18 and heterorhabditis megidis at 7 sites of 125 sampled. most nematodes were found where visible insect infestation occurred and where human influence on the habitat was substantial (e.g., agricultural, foreste ...199319279830
effects of two carbamates on infective juveniles of stemernema carpocapsae all strain and steinernema feltiae umeå strain.laboratory bioassays were conducted to determine the effects of two carbamates, carbofuran (an acetylcholinesterase inhibitor) and fenoxycarb (a juvenile hormone analog), on survival and infectivity of the infective juveniles (ij) of steinernema feltiae umeå strain and steinernema carpocapsae all strain. both insecticides caused mortality of ij in a dose-related fashion. the two nematode species were equally sensitive to fenoxycarb (ld ca. 0.03mg/ml). whereas ij of s. feltiae were several orders ...199619277148
greenhouse and field evaluations of entomopathogenic nematodes (nematoda:heterorhabditidae and steinernematidae) for control of cabbage maggot (diptera:anthomyiidae) on cabbage.entomopathogenic nematodes--heterorhabditis bacteriophora poinar (oswego strain), steinernema carpocapsae (weiser) (ny001 strain), steinernema carpocapsae (25 strain), steinernema feltiae filipjev (= neoaplectana carpocapsae weiser) (369 strain), steinernema feltiae (27 strain), and steinernema riobravus cabanillas and poinar (355 strain)--were examined for pathogenicity against cabbage maggot, delia radicum (l.), larvae in the greenhouse and field. applications (per plant) of 3,000 and 4,000 in ...19968913112
natural occurrence of entomopathogenic nematodes (rhabditida: steinernematidae and heterorhabditidae) in spanish soilsentomopathogenic nematodes (steinernematidae and heterorhabditidae) were surveyed in spanish soils using the galleria baiting technique. a total of 750 soil samples were taken from 150 sites representing different regions and habitat types (cropland, woodland, and pasture). entomopathogenic nematodes were recovered from 35 sites; 33 sites were positive for the occurrence of steinernematids and 2 sites for heterorhabditids. five distinct morphological types of steinernematids were recovered: stei ...19968812576
rflp analysis of pcr amplified its and 26s ribosomal rna genes of selected entomopathogenic nematodes (steinernematidae, heterorhabditidae).this study examined the polymerase chain reaction (pcr) amplified internal transcribed spacer (its) and 26s ribosomal dna (rdna) regions of 15 entomopathogenic nematode isolates including steinernema feltiae syn. bibionis, s. glaseri, seven strains of s. carpocapsae, four strains of heterorhabditis bacteriophora, and two field isolates. rdna length variation was not observed among the isolates examined. restriction fragment length polymorphisms (rflp) of pcr amplified its and 26s regions provide ...199619277341
compatibility of soil amendments with entomopathogenic nematodes.the impact of inorganic and organic fertilizers on the infectivity, reproduction, and population dynamics of entomopathogenic nematodes was investigated. prolonged (10- to 20-day) laboratory exposure to high inorganic fertilizer concentrations inhibited nematode infectivity and reproduction, whereas short (1-day) exposures increased infectivity. heterorhabditis bacteriophora was more sensitive to adverse effects than were two species of steinernema. in field studies, organic manure resulted in i ...199719274153
desiccation survival of populations of the entomopathogenic nematodes steinernema feltiae and heterorhabditis megidis from greece and the uk.the desiccation survival and ability to control water loss during drying of individual infective juveniles (ijs) of populations of steinernema feltiae and heterorhabditis megidis from greece and the uk were examined at different relative humidities. survival at all relative humidities was for minutes only and there was no evidence of enhanced survival of the populations of either species from greece compared with those from the uk. the survival of individuals of both populations of h. megidis wa ...19979166440
pathogenicity of axenic steinernema feltiae, xenorhabdus bovienii, and the bacto-helminthic complex to larvae of tipula oleracea (diptera) and galleria mellonella (lepidoptera).the pathogenicity of the nematode-bacterium complex steinernema feltiae-xenorhabdus bovienii to larvae of tipula oleracea and galleria mellonella was investigated by injection of dauer juvenile nematodes carrying their bacterial symbiont cells (monoxenic nematodes). axenic nematodes (free of bacteria) and the symbiotic bacteria themselves were tested. the lc50 of x. bovienii in t. oleracea was 15,700 colony forming units (cfu)/larva compared to < or = 8 cfu in g. mellonella. xenorhabdus bovienii ...19979170346
encapsulation of the entomopathogenic nematode steinernema feltiae in tipula oleracea.the encapsulation response of tipula oleracea to the entomopathogenic nematode steinernema feltiae was investigated by exposing the insects to nematode dauer juveniles (djs) and by injecting djs with and without the symbiotic bacteria xenorhabdus bovienii. the encapsulation response varied considerably between individual insect larvae. the variation could not be attributed to a more or less scattered nematode invasion over time since it was also recorded after simultaneous injection of a fixed d ...19979170347
the efficacy of entomopathogenic nematodes for controlling housefly infestations of intensive pig units.the efficacy of the entomopathogenic nematodes steinernema feltiae and heterorhabditis megidis after formulation into a housefly bait was compared with a commercial bait formulation of methomyl for the control of houseflies in a u.k. pig farm. the housefly infestation was confined to the farrowing unit, which consisted of ten farrowing houses, where two adjacent houses were sequentially re-stocked with pregnant sows at weekly intervals. shortly after re-stocking, one house was baited with one of ...19989513938
interaction of entomopathogenic nematodes (steinernematidae) with selected species of ixodid ticks (acari: ixodidae).entomopathogenic nematodes, currently used for biological control of various insect pests, were tested for their ability to penetrate and kill replete females of several species of ticks including dermacentor variabilis (say), rhipicephalus sanguineus (latreille), amblyomma maculatum koch, and a. cajennense (f.). these species were found to be susceptible to the entomopathogenic nematodes, steinernema feltiae (filipjev) or s. riobravus (cabanillas & poinar), shown in previous studies in our labo ...19989701938
routes of penetration of the entomopathogenic nematode steinernema feltiae attacking larval and adult houseflies (musca domestica)the way in which steinernema feltiae (nematoda: rhabditida: steinernematidae) infects the housefly, musca domestica (diptera: muscidae), was investigated. adult flies were confined in petri dishes containing 1 million s. feltiae on capillary matting and individuals were dissected at hourly intervals. first, second, and third instar larvae were placed on filter papers with 100,000 infective juveniles, and then 2 larvae were examined at 30-min intervals. infective juveniles were aggregated on the ...19989784352
virulence of entomopathogenic nematodes to the western masked chafer cyclocephala hirta (coleoptera: scarabaeidae).predictability is a key challenge in biological control of white grubs with entomopathogenic nematodes. most field test failures have been attributed to the use of inappropriate nematode strains. we evaluated several species and strains of entomopathogenic nematodes (heterorhabditidae and steinernematidae) against chafer cyclocephala hirta in a soil and pot bioassay at 25 degrees c. the nj65 strain of steinernema glaseri, isolated from new jersey, outperformed all other steinernematid and hetero ...19989589628
pest status of american plum borer (lepidoptera: pyralidae) and fruit tree borer control with synthetic insecticides and entomopathogenic nematodes in new york state.surveys were conducted in 1994 and 1995 to determine the pest status of the american plum borer, euzophera semifuneralis (walker), in new york state stone fruit crops. these surveys indicate that american plum borer is the most important of the wood-boring insects infesting tart cherries and also is an important pest in peaches suffering from canker diseases. it is not prevalent in plums or in healthy peaches. trials to control american plum borer were conducted in tart cherry and peach by using ...199910036985
successful parasitation of locusts by entomopathogenic nematodes is correlated with inhibition of insect phagocytes.the entomopathogenic nematodes heterorhabditis megidis and steinernema feltiae turned out to be successful antagonists of the orthopteran insects locusta migratoria and schistocerca gregaria. the death rate of locusts maintained on nematode-inoculated sand was remarkably high. even dosages as low as one nematode per cubic centimeter of sand killed approximately 50% of the locusts within 10 days. the impact of parasitation on locusts' immune defense was closely investigated for l. migratoria para ...199910066395
host range, specificity, and virulence of steinernema feltiae, steinernema rarum, and heterorhabditis bacteriophora (steinernematidae and heterorhabditidae) from argentina.infections were carried out in the laboratory to determine the host range, specificity, and virulence of steinernema rarum, s. feltiae, and heterorhabditis bacteriophora that were isolated from different regions of argentina. all insect orders showed a remarkable susceptibility to the three nematode species, showing mortality values higher than 66%, except for anoplura. the mortality of the insects of agronomic interest was more than 90%. as for insects of sanitary importance, s. feltiae and s. ...199910222175
phenotypic characterization of the xenorhabdus bacterial symbiont of a texas strain of the entomopathogenic nematode steinernema riobrave, and characterization of the xenorhabdus bovienii bacterial symbiont of a newfoundland strain of steinernema feltiae.two bacterial symbionts of entomopathogenic nematodes, one of which originated from texas, u.s.a., and the other from newfoundland, canada, were characterized phenotypically. these strains belonged to the genus xenorhabdus. the newfoundland (nf) strain was shown to be x. bovienii but the texas (tx) strain was not identified at the species level. four additional cultures of xenorhabdus were included in the study. these were a strain of x. bovienii (umeå), which was from a nematode of european ori ...200010932355
[the distribution of entomopathogenic nematodes of the families steinernematidae and heterorabditidae in russia and their morphological characteristics].the data on a distribution of nematode species of the families steinernematidae and heterorabditidae in the northern and southern regions of the russian federation are given. morphological characters of geographic isolates of some nematode species are not different, while their invasive activities in dependence of a temperature are different. steinernema feltiae occurs in all climate zones, s. carpocapsae is restricted in distribution, nematode species of the family heterorabditidae were found i ...200011060891
spatial structuring and frequency distribution of the nematode steinernema feltiae filipjev.the frequency distribution of first generation, steinernema feltiae filipjev parasitic stages was over-dispersed with the majority of hosts containing few or no parasitic stages, whilst a few hosts contained a great many. because of high extraction efficiency, the frequency distributions of the parasitic stages and the infective stages in the soil were assumed to be directly related. to explain the frequency distribution of the parasites it was therefore necessary to account for the frequency di ...200011072905
re-assessing the infection strategies of the entomopathogenic nematode steinernema feltiae (rhabditidae; steinernematidae).previous studies have indicated that between 60 and 80% of a population of entomopathogenic nematodes do not infect their insect hosts at any one period in time. two hypotheses explain this behaviour: the first that there is a subpopulation of non-infectious nematodes and the second that the non-infectious group is created by inhibitory cues derived from infected insects. through an experimental approach with the galleria mellonella-steinernema feltiae system we show that both mechanisms operate ...200011085241
influence of insect larvae and seedling roots on the host-finding ability of steinernema feltiae (nematoda: steinernematidae).the ability of nematode foragers to locate appropriate insect hosts is essential to their performance as successful biological control agents. we investigated the host-finding ability and chemotaxis of steinernema feltiae in the presence of cues from galleria mellonella larvae and tomato and radish seedling roots, given individually and in combination, over 120 min. in agar arena tests, infective juveniles of s. feltiae responded positively to unsterilized and sterilized larvae and tomato seedli ...200010772328
efficacy of entomopathogenic nematodes against soil-dwelling life stages of western flower thrips, frankliniella occidentalis (thysanoptera: thripidae).the efficacy of six entomopathogenic nematode (epn) strains was tested in a laboratory study against soil-dwelling life stages of western flower thrips (wft), frankliniella occidentalis (pergande) (thysanoptera: thripidae). the epn strain collections screened included two heterorhabditis bacteriophora species, i.e., h. bacteriophora hk3 (h.b h) and h. bacteriophora hb brecan (h.b b), three steinernema feltiae species, i.e., s. feltiae sylt (s.f s), s. feltiae obsiii (s.f o), and s. feltiae strai ...200111812114
developmental temperature effects on five geographic isolates of the entomopathogenic nematode steinernema feltiae (nematoda: steinernematidae).the development of five geographic isolates of steinernema feltiae at 5, 8, 10, 15, 20, 25, and 28 degrees c in wax moth, galleria mellonella, larvae was examined. the isolates were from mediterranean (sinop from turkey, sn from france, and monterey from california), subtropical (rafaela from argentina), and tropical (mg-14 from hawaii) regions. all isolates caused 100% mortality of wax moth larvae and developed and produced progeny between 8 and 25 degrees c. at 28 degrees c, mortality was 100% ...200111437527
characterisation of symbionts of entomopathogenic nematodes by universally primed-pcr (up-pcr) and up-pcr product cross-hybridisation.this work introduces and demonstrates the applicability of universally primed-pcr (up-pcr) for differentiating bacterial symbionts of entomopathogenic nematodes. furthermore, typing by up-pcr product cross-hybridisation was successfully introduced to cluster the bacterial strains. the work was initiated by isolating 10 isolates of photorhabdus temperata (s172) from the nematode host heterorhabditis sp. (dk172) and 12 isolates of xenorhabdus bovienii (s1) from the nematode steinernema feltiae (dk ...200212393202
effects of etomopathiogenic nematodes on meloidogyne javanica on tomatoes and soybeans.two hawaiian isolates of steinernema feltiae mg-14 and heterohabditis indica mg-13, a french isolate of s. feltiae sn, and a texan isolate of s. riobrave tx were tested for their efficacy against the root-knot nematode, meloidogyne javanica, in the laboratory and greenhouse. experiments were conducted to investigate the effects of treatment application time and dose on m. javanica penetration in soybean, and egg production and plant development in tomato. two experiments conducted to assess the ...200219265939
host cadavers protect entomopathogenic nematodes during freezing.the entomopathogenic nematodes heterorhabditis bacteriophora, steinernema carpocapsae, steinernema glaseri, and steinernema feltiae were exposed to freezing while inside their hosts. survival was assessed by observing live and dead nematodes inside cadavers and by counting the infective juveniles (ijs) that emerged after freezing. we (1) measured the effects of 24h of freezing at different times throughout the course of an infection, (2) determined the duration of freezing entomopathogenic nemat ...200212417210
use of entomopathogenic nematodes to suppress meloidogyne incognita on greenhouse tomatoes.tomato seedlings in a growth chamber were inoculated with 150 meloidogyne incognita eggs and 25 infective juveniles (ij)/cm² of steinernema feltiae, s. riobrave, or heterorhabditis bacteriophora. with the exception of seedling roots treated with h. bacteriophora, all seedlings treated with entomopathogenic nematodes had fewer m. incognita juveniles inside roots and produced fewer eggs than the control seedlings. tomato plants in the greenhouse were infested with 4,000 m. incognita eggs and treat ...200219265927
distribution patterns of entomopathogenic nematodes applied through drip irrigation systems.the distribution of entomopathogenic nematodes applied by drip irrigation was evaluated by injecting small volumes of steinernema carpocapsae (weiser) all strain, steinernema feltiae (filipjev) sn strain, steinernema glaseri steiner, and heterorhabditis bacteriophora hp 88 strain poinar suspensions into drip irrigation lines. additionally, steinernema riobrave cabanillas, poinar, & raulston, and s. carpocapsae were injected in a 10-liter volume of water with an injection pump. overall, the nemat ...200314994792
the efficacy of the entomopathogenic nematode, steinernema feltiae, against the immature stages of bemisia tabaci. 200312877837
acclimation of entomopathogenic nematodes to novel temperatures: trehalose accumulation and the acquisition of thermotolerance.the effect of thermal acclimation on trehalose accumulation and the acquisition of thermotolerance was studied in three species of entomopathogenic nematodes adapted to either cold or warm temperatures. all three steinernema species accumulated trehalose when acclimated at either 5 or 35 degrees c, but the amount of trehalose accumulation differed by species and temperature. the trehalose content of the cold adapted steinernema feltiae increased by 350 and 182%, of intermediate steinernema carpo ...200312633652
interaction of microbial populations in steinernema (steinernematidae, nematoda) infected galleria mellonella larvae.infection of galleria mellonella larvae with the entomopathogenic nematodes steinernema feltiae (a21 and r strains) and steinernema glaseri (dongrae) resulted in several species of bacteria, including the respective bacterial symbiont, xenorhabdus spp., growing in the infected insect cadavers. these other bacteria were enterococcus in all three nematode infections studied and acinetobacter in the s. feltiae infections. the respective populations of these bacteria changed with time. following inf ...200312788281
the role of steinernema feltiae body-surface lipids in host-parasite immunological interactions.interactions between entomopathogenic nematodes (steinernema feltiae) and insect host (galleria mellonella) immune system were investigated. we focused on the immunosuppressive properties of the parasite cuticle and on its interaction with hemolymph humoral components. effects of parasite cuticle against host propo system enzymatic cascade were evaluated a short time after infection. the presence of parasite cuticles decreased both normal and lps-elicited propo system activity, suggesting that s ...200415287592
rapid age-related changes in infection behavior of entomopathogenic nematodes.nonfeeding infective juvenile (ij) entomopathogenic nematodes (epns) are used as biological agents to control soil-dwelling insects, but poor storage stability remains an obstacle to their widespread acceptance by distributors and growers as well as a frustration to researchers. age is one factor contributing to variability in epn efficacy. we hypothesized that age effects on the infectiousness of ijs would be evident within the length of time necessary for ijs to infect a host. the penetration ...200415715211
effect of application method on fitness of entomopathogenic nematodes emerging at different times.the entomopathogenic nematode species steinernema feltiae and heterorhabditis bacteriophora were compared for survival and infectivity of infective juveniles (ij) collected with a standard white trap (i.e., emerging from hosts and accumulating in water) and later applied to sand (treatment a) to ij allowed to emerge from hosts into sand (treatment c). percentage ij survival and infectivity was compared between treatments for s. feltiae ij that emerged between days 1 to 3 and days 4 to 6. for h. ...200419262835
target host finding by steinernema feltiae and heterorhabditis bacteriophora in the presence of a non-target insect host.the ability of steinernema feltiae or heterorhabditis bacteriophora infective juveniles (ij), when applied to the soil surface, to infect a galleria mellonella larva at the base of a soil-filled cup (276 cm(3)) was evaluated in the presence and absence of 100 larvae of a non-target insect, the aphid midge aphidoletes aphidimyza, near the soil surface. in all four trials with either s. feltiae or h. bacteriophora, a. aphidimyza presence did not affect the number of ij finding and infecting a g. m ...200419262818
parasitism of bark scorpion centruroides exilicauda (scorpiones: buthidae) by entomopathogenic nematodes (rhabditida: steinernematidae; heterorhabditidae).in laboratory bioassays, steinernema glaseri steiner, steinernema riobrave cabanillas, poinar & raulston, heterorhabditis bacteriophora poinar, and heterorhabditis marelatus liu & berry were capable of infecting and killing the bark scorpion, centruroides exilicauda (wood). steinernema feltiae (filipjev) and steinernema carpocapsae (weiser) failed to infect c. exilicauda at 22 degrees c. s. glaseri, h. marelatus, and h. bacteriophora caused significant mortality at 22 degrees c, indicating the p ...200516334314
factors affecting entomopathogenic nematodes (steinernematidae) for control of overwintering codling moth (lepidoptera: tortricidae) in fruit bins.fruit bins infested with diapausing codling moth larvae, cydia pomonella (l.), are a potential source of reinfestation of orchards and may jeopardize the success of mating disruption programs and other control strategies. entomopathogenic nematodes (epns) were tested as a potential means of control that could be applied at the time bins are submerged in dump tanks. diapausing cocooned codling moth larvae in miniature fruit bins were highly susceptible to infective juveniles (ijs) of steinernema ...200516539105
steinernema akhursti sp. n. (nematoda: steinernematidae) from yunnan, china.a new species of entomopathogenic nematode, herein described as steinernema akhursti sp. n., was recovered from soil samples collected from yunnan province, the people's republic of china. both morphological and molecular data show congruently that s. akhursti sp. n. belongs to the steinernema feltiae group. it can be separated from all described steinernema species by the combined morphological and morphometrical characters of various stages of the nematodes. for the first generation male, the ...200516289544
protein interaction of nucleosome assembly protein 1 and casein kinase 2 during desiccation response in the insect-killing nematode steinernema feltiae is-6.the change in gene expression induced by desiccation in the semiarid, entomopathogenic nematode steinernema feltiae is-6, includes induction of transcription of a nucleosome assembly protein, nap1 homolog, and of casein kinase 2 (ck2) genes. therefore, one of the events during the dehydration response of s. feltiae is-6 may be transcriptional activation by s. feltiae is-6 nap1 homolog (sf-nap1), which is regulated by s. feltiae is-6 ck2 (sf-ck2). this regulation necessitates physical interaction ...200516108569
temporal association of entomopathogenic nematodes (rhabditida: steinernematidae and heterorhabditidae) and bacteria.galleria mellonella l. larvae were infected with three species (seven strains) of steinernema spp. or three species (three strains) of heterorhabditis spp. infected larvae were incubated at 22, 27, and 32 degrees c. larvae were dorsally dissected every 6h over a 48-h period. hemolymph was collected and streaked on tryptic soy agar plates. several non-symbiotic bacterial species were identified from infected insect cadavers: enterobacter gergoviae, vibrio spp., pseudomonas fluorescens type c, ser ...200616448667
control of the oriental fruit moth, grapholita molesta, using entomopathogenic nematodes in laboratory and fruit bin assays.the oriental fruit moth (ofm), grapholita molesta (busck), which is among the most important insect pests of peaches and nectarines, has developed resistance to a wide range of insecticides. we investigated the ability of the entomopathogenic nematodes (epn) steinernema carpocapsae (weiser), s. feltiae (filipjev), s. riobrave (cabanillas et al.), and heterorhabditis marelatus (liu and berry) to control ofm under laboratory and fruit bin conditions. at a dosage of 10 infective juveniles (ij)/cm(2 ...200619259443
entomopathogenic nematodes and bacteria applications for control of the pecan root-knot nematode, meloidogyne partityla, in the greenhouse.meloidogyne partityla is a parasite of pecan and walnut. our objective was to determine interactions between the entomopathogenic nematode-bacterium complex and m. partityla. specifically, we investigated suppressive effects of steinernema feltiae (strain sn) and s. riobrave (strain 7-12) applied as infective juveniles and in infected host insects, as well as application of s. feltiae's bacterial symbiont xenorhabdus bovienii on m. partityla. in two separate greenhouse trials, the treatments wer ...200619259462
pathogenicity of the nematode steinernema feltiae filipjev in relation to different insect hosts. 20063373057
phoresy of the entomopathogenic nematode steinernema feltiae by the earthworm eisenia fetida.the free-living stage of entomopathogenic nematodes occurs in soil, and is an environmental-friendly alternative for biological control. however, their dispersal capability is limited. earthworms improve soil characteristics, changing soil structure and influencing many edaphic organisms. thus, earthworms could be used as vectors to introduce/disperse beneficial organisms. nevertheless this interaction has not been studied in detail. this study presents the infectivity results of steinernema fel ...200616542677
molecular detection of predation by soil micro-arthropods on nematodes.the relative importance of the factors driving change in the population dynamics of nematodes in the soil is almost completely unknown. top-down control by micro-arthropod predators may have a significant impact on nematode population dynamics. we report experiments showing that mites and collembola were capable of reducing nematode numbers in the laboratory and were feeding on a targeted nematode species in the field. a pcr-based approach was developed for the detection of predation on three sp ...200616689911
emergence and dispersal patterns of two isolates of the entomopathogenic nematode steinernema feltiae.few studies have addressed the role of the sexes in the emergence and dispersal of entomopathogenic nematodes from host insects. individuals of two isolates of steinernema feltiae, uk76 and sbil, emerging from galleria mellonella cadavers were classed as non-dispersed (remaining on the cadaver for up to nine days) and dispersed (actively moving away from the cadaver). sex ratios within both classes were examined in infective (individuals that successfully invaded bait g. mellonella) and entire ( ...200619259450
morphological and ecological characterization of steinernema feltiae (rhabditida: steinernematidae) rioja strain isolated from bibio hortulanus (diptera: bibionidae) in spain.a new strain of steinernema feltiae (rhabditida: steinernematidae) was isolated in la rioja (spain) from larvae of bibio hortulanus (diptera: bibionidae). a comparative morphometric analysis of this new strain and four additional s. feltiae isolates was performed. although significant differences in morphometric measurements were observed, pcr-rflp profiles and sequence analysis of the its region of rdna confirmed the identity of the new strain as a2 rflp type of s. feltiae. a comparative morpho ...200619259432
dynamics of carbon dioxide release from insects infected with entomopathogenic nematodes.the quality of an insect as a host to an entomopathogenic nematode infective juvenile depends in part on whether or not the insect is already infected and on the stage of that infection. previous research has shown that nematode response to hosts can change after infection and that, for uninfected hosts, co(2) can be an important cue used by infective stage juveniles during attraction. we hypothesized that co(2) production from an insect changes after it is infected, and that these changes could ...200717054978
soil mediates the interaction of coexisting entomopathogenic nematodes with an insect host.we tested for soil substrate effects on the movement and infectivity of naturally co-occurring entomopathogenic nematodes steinernema feltiae and heterorhabditis marelatus, alone and in combination. we manipulated the presence and bulk density of soil and added galleria mellonella baits within capped and perforated 15ml centrifuge tubes. sampling tubes were then deployed in situ into field and laboratory settings as experimental traps for infective juveniles. in comparisons with standard soil co ...200717005194
efficacy of the entomopathogenic nematode, steinernema feltiae, against sweetpotato whitefly bemisia tabaci (homoptera: aleyrodidae) under laboratory and glasshouse conditions.the potential of using the entomopathogenic nematode steinernema feltiae to control the sweetpotato whitefly bemisia tabaci (gennadius) has been established in previous laboratory studies. however, laboratory studies can overestimate the level of control achieved by biocontrol agents in the glasshouse. glasshouse trials are therefore required to confirm laboratory results before full-scale commercial development is considered. under both controlled laboratory and glasshouse conditions high morta ...200717298677
predation of entomopathogenic nematodes by sancassania sp. (acari: acaridae).predation of the entomopathogenic nematode, steinernema feltiae (rhabditida: steinernematidae), by sancassania sp. (acari: acaridae) isolated from field-collected scarab larvae was examined under laboratory conditions. adult female mites consumed more than 80% of the infective juvenile (ij) stage of s. feltiae within 24 h. when s. feltiae ijs were exposed to the mites for 24 h and then exposed to galleria mellonella (lepidoptera: pyralidae) larvae, the number of nematodes penetrating into the la ...200717924198
immune suppression of galleria mellonella (insecta, lepidoptera) humoral defenses induced by steinernema feltiae (nematoda, rhabditida): involvement of the parasite cuticle.immune depression of galleria mellonella larvae was evaluated a short time after infection with the entomopathogenic nematode steinernema feltiae. in the host the activity of the enzymatic cascade known as the propo system was significantly reduced by the presence of either live or dead parasites. the presence of parasites decreased the lps-elicited propo system activity. in addition, this process seems to be related to a decrease in the activity of hemolymph proteases, more than to phenoloxidas ...200712427469
effect of entomopathogenic nematodes (rhabditida: steinernematidae and heterorhabditidae) on meloidogyne mayaguensis rammah and hirschmann (tylenchida: meloidoginidae) infection in tomato plants.some studies suggest that entomopathogenic nematodes (epn) affect plant-parasitic nematode populations. here, the effects of live and dead ij of heterorhabditis bacteriophora jpm4, h. baujardi lpp7, steinernema feltiae sn and s. carpocapsae all were evaluated against eggs and j2 of the plant-parasitic nematode meloidogyne mayaguensis. according to treatment, 100 ij were applied with 350 eggs, 350 j2 or 175 eggs + 175 j2 to tomato plants. bioassays were conducted in march to may and repeated in s ...200719259509
relationship between the successful infection by entomopathogenic nematodes and the host immune response.reproduction of entomopathogenic nematodes requires that they escape recognition by a host's immune system or that they have mechanisms to escape encapsulation and melanization. we investigated the immune responses of larvae for the greater wax moth (galleria mellonella), tobacco hornworm (manduca sexta), japanese beetle (popillia japonica), northern masked chafer (cyclocephala borealis), oriental beetle (exomala orientalis) and adult house crickets (acheta domesticus), challenged with infective ...200717275827
steinernema feltiae: ammonia triggers the emergence of their infective juveniles.entomopathogenic nematodes complete their life cycles inside dead insects. the emergence of new infective juveniles from the cadaver has been attributed (but never demonstrated) to food depletion or to the accumulation of metabolites from the breakdown of the host's tissues. here we give evidence that emergence is triggered by ammonia, a product of nematode defecation. we found that the emergence of steinernemafeltiae infective juveniles from galleriamellonella cadavers was stimulated by a parti ...200818316080
pathogenic effect of entomopathogenic nematode-bacterium complexes on terrestrial this study, we evaluated the effect of entomopathogenic nematodes (epns) steinernema carpocapsae, steinernema feltiae and heterorhabditis bacteriophora, symbiotically associated with bacteria of the genera xenorhabdus or photorhabdus, on the survival of eight terrestrial isopod species. the epn species s. carpocapsae and h. bacteriophora reduced the survival of six isopod species while s. feltiae reduced survival for two species. two terrestrial isopod species tested (armadillidium vulgare an ...200818346756
establishment, persistence, and introgression of entomopathogenic nematodes in a forest ecosystem.entomopathogenic nematodes (epn) are currently marketed worldwide for use in inundative biological control, where the applied natural enemy population (rather than its offspring) is expected to reduce insect numbers. unlike classical biological control, in inundative control natural enemy establishment is not crucial in order to achieve pest suppression. field trials in irish forestry provided the opportunity to test predictions regarding the establishment of two exotic (steinernema carpocapsae ...200818488631
multiple-species natural enemy approach for biological control of alfalfa snout beetle (coleoptera: curculionidae) using entomopathogenic nematodes.multiple-species natural enemy approach for the biological control of the alfalfa snout beetle, otiorhynchus ligustici (l.) (coleoptera: curculionidae), was compared with using single-species of natural enemies in the alfalfa ecosystem by using entomopathogenic nematodes with different dispersal and foraging behaviors. steinernema carpocapsae ny001 (ambush nematode), heterorhabditis bacteriophora oswego (cruiser nematode), and steinernema feltiae valko (intermediate nematode) were applied in sin ...200818950034
potential of two entomopathogenic nematodes for suppression of plum curculio (conotrachelus nenuphar, coleoptera: curculionidae) life stages in northern climates.plum curculio, conotrachelus nenuphar, is a major pest of pome and stone fruits in north america. we evaluated the potential efficacy of two entomopathogenic nematode species for suppression of plum curculio in northern regions, targeting life stages that reside in soil during spring and summer. a strain of heterorhabditis bacteriophora isolated from soil infested with plum curculio in northern utah and a commercially available strain of steinernema feltiae known to tolerate cool temperatures we ...200819036207
effectiveness of different species of entomopathogenic nematodes for biocontrol of the mediterranean flatheaded rootborer, capnodis tenebrionis (linné) (coleoptera: buprestidae) in potted peach tree.the susceptibility of larvae of the mediterranean flatheaded rootborer (capnodis tenebrionis) to 13 isolates of entomopathogenic nematodes was examined using gf-677 potted trees (peachxalmond hybrid) as the host plant. the nematode strains tested included nine steinernema feltiae, one s. affine, one s. carpocapsae and two heterorhabditis bacteriophora. nematodes showed the ability to locate and kill larvae of c. tenebrionis just after they enter into the roots of the tree. s. feltiae strains pro ...200817950309
expression of different desiccation-tolerance related genes in various species of entomopathogenic nematodes.entomopathogenic nematodes used as biological control agents encounter various stress conditions during extended periods in the soil. we investigated gene expression in nematodes that were tolerant or susceptible to desiccation stress to determine whether enhanced tolerance in these populations results from a 'gene-expression response' to desiccation or if, for enhanced tolerance, no such response is needed, perhaps due to a state of constant 'readiness'. the expressions of four genes, aldehyde ...200818179831
cuticular surface lipids are responsible for disguise properties of an entomoparasite against host cellular responses.entomopathogenic nematodes are widely used as alternatives to chemicals for the biological control of insects. these endoparasites are symbiotically associated with bacteria that are lethal for the host; however, parasites need to overcome the host immune defences to complete a successful life cycle. the processes parasites employ to escape or depress host immunity are targeted at deceiving non-self recognition as well as inactivating defence reactions. the purpose of this paper is to investigat ...200818374979
host resistance reverses the outcome of competition between microparasites.predators and parasites can control the abundance or biomass of herbivores with indirect effects on producer communities and ecosystems, but the interplay of multiple natural enemies may yield unexpected dynamics. we experimentally examined interactions between two microparasites (entomopathogenic nematodes) isolated from sandy grassland soils of coastal california: heterorhabditis marelatus (heterorhabditidae) and steinernema feltiae (steinernematidae). heterorhabditis marelatus drives trophic ...200919694121
steinernema xueshanense n. sp. (rhabditida, steinernematidae), a new species of entomopathogenic nematode from the province of yunnan, southeast tibetan mts., china.during a random epn survey in the northern part of the yunnan province (southeastern tibet, dequen district, town of dequen) in 2005, soil samples containing an unknown epn species were collected. the new species is described herein as steinernema xueshannense n. sp. named after the xue shan mts. a mountain range between yunnan and tibet where the nematode was collected. the isolate is a new species belonging to the steinernema feltiae /kraussei group. s. xueshanense n. sp. is characterized by m ...200919460386
nontarget effect of entomopathogenic nematodes on larvae of twospotted lady beetle (coleoptera: coccinellidae) and green lacewing (neuroptera: chrysopidae) under laboratory conditions.the nontarget effect of steinernema feltiae, steinernema carpocapsae, heterorhabditis bacteriophora, and three mixed suspensions of two species of entomopathogenic nematodes on the larvae of the twospotted lady beetle, adalia bipunctata (l.) (coleoptera: coccinellidae), and on the larvae of the lacewing chrysoperla carnea (stephens) (neuroptera: chrysopidae), were studied in a laboratory bioassay. the assay was performed at three temperature (15, 20, and 25 degrees c) and at three different conc ...200919736754
screening spanish isolates of steinernematid nematodes for use as biological control agents through laboratory and greenhouse microcosm studies.entomopathogenic nematodes (epns) are one of the best non-chemical alternatives for insect pest control, with native epn strains that are adapted to local conditions considered to be ideal candidates for regional biological control programs. virulence screening of 17 native mediterranean epn strains was performed to select the most promising strain for regional insect pest control. steinernema feltiae (filipjev) (rhabditida: steinernematidae) rioja strain produced 7%, 91% and 33% larval mortalit ...200919073191
influence of cell density and phase variants of bacterial symbionts (xenorhabdus spp.) on dauer juvenile recovery and development of biocontrol nematodes steinernema carpocapsae and s. feltiae (nematoda: rhabditida).the rhabditid nematodes steinernema carpocapsae and steinernema feltiae are used in biological control of insect pests. mass production is done in liquid culture media pre-incubated with their bacterial symbionts xenorhabdus nematophila and xenorhabdus bovienii, respectively, before nematode dauer juveniles (djs) are inoculated. as a response to food signals produced by the bacterial symbionts, the djs exit from the developmentally arrested dauer stage (they recover development) and grow to adul ...200919319521
effect of temperature on the development of steinernema carpocapsae and steinernema feltiae (nematoda: rhabditida) in liquid culture.for commercial use of the entomopathogenic nematodes steinernema carpocapsae and steinernema feltiae in biological control of insect pests, they are produced in liquid culture on artificial media pre-incubated with their symbiotic bacteria xenorhabdus nematophila and xenorhabdus bovienii, respectively. after 1 day of the bacterial culture, nematode dauer juveniles (djs) are inoculated, which recover development. the adult nematodes produce dj offspring, which are harvested and can be sprayed. th ...200919455323
biological control of lycoriella ingenua (diptera: sciaridae) in commercial mushroom (agaricus bisporus) cultivation: a comparison between hypoaspis miles and steinernema feltiae.mushroom cultivation may be adversely affected by insect pests, including sciarids (lycoriella spp.), which were previously controlled by application of chemical pesticides. however, owing to food safety and environmental concerns, availability of pesticides for use during mushroom cultivation has diminished. consequently, it is imperative to investigate alternative control strategies, not reliant on chemical pesticides, which may be used in an integrated pest management system.200919562663
characterization of xenorhabdus isolates from la rioja (northern spain) and virulence with and without their symbiotic entomopathogenic nematodes (nematoda: steinernematidae).eighteen xenorhabdus isolates associated with spanish entomopathogenic nematodes of the genus steinernema were characterized using a polyphasic approach including phenotypic and molecular methods. two isolates were classified as xenorhabdus nematophila and were associated with steinernema carpocapsae. sixteen isolates were classified as xenorhabdus bovienii, of which fifteen were associated with steinernema feltiae and one with steinernema kraussei. two x. bovienii phase ii were also isolated, o ...200919682458
manifold aspects of specificity in a nematode-bacterium mutualism.coevolution in mutualistic symbiosis can yield, because the interacting partners share common interests, to coadaptation: hosts perform better when associated with symbionts of their own locality than with others coming from more distant places. however, as the two partners of a symbiosis might also experience conflicts over part of their life cycle, coadaptation might not occur for all life-history traits. we investigated this issue in symbiotic systems where nematodes (steinernema) and bacteri ...200919732258
virulence and competitiveness: testing the relationship during inter- and intraspecific mixed infections.understanding the reasons why different parasites cause different degrees of harm to their hosts is an important objective in evolutionary biology. one group of models predicts that if hosts are infected with more than one strain or species of parasite, then competition between the parasites will select for higher virulence. while this idea makes intuitive sense, empirical data to support it are rare and equivocal. we investigated the relationship between fitness and virulence during both inter- ...201020394652
a pathogenic parasite interferes with phagocytosis of insect immunocompetent cells.phagocytosis activity of hemocytes of the host galleria mellonella (lepidoptera) was modulated by the infection of the entomopathogenic nematode steinernema feltiae (rahbditida) and was found to be correlated with the opsonization of bacteria by hemolymph factors. the presence of nematodes resulted in a significative decrease in phagocytosis of bacteria by host hemocytes, both in in vivo and in in vitro assays. host interacting proteins (hips), which appear to function as opsonic factors and are ...201020457179
mortality of four stored product pests in stored wheat when exposed to doses of three entomopathogenic nematodes.the insecticidal effect of heterorhabditis bacteriophora poinar (nematoda: heterorhabditidae), steinernema carpocapsae (weiser) (nematoda: steinernematidae), and steinernema feltiae (filipjev) (nematoda: steinernematidae) against mediterranean flour moth, ephestia kuehniella (zeller) (lepidoptera: pyralidae) (larvae), lesser grain borer, rhyzopertha dominica (f.) (coleoptera: bostrychidae) (adults), rice weevil, sitophilus oryzae (l.) (coleoptera: curculionidae) (adults), and confused flour beet ...201020568646
in vitro infection of sheep lice (bovicola ovis schrank) by steinernematid and heterorhabditid nematodes.control of sheep lice with conventional pesticides can be compromised by difficulty in contacting lice in the dense water repellent fleeces of sheep, particularly when sheep have not been recently shorn. entomopathogenic nematodes (ens) are motile and are able to actively seek out insect hosts. they have particular advantages for the control of pests in cryptic habitats, such as the fleeces of sheep and avoid many of the problems frequently associated with chemical controls. this study investiga ...201020800970
influence of inoculum density on population dynamics and dauer juvenile yields in liquid culture of biocontrol nematodes steinernema carpocapsae and s. feltiae (nematoda: rhabditida).for improvement of mass production of the rhabditid biocontrol nematodes steinernema carpocapsae and steinernema feltiae in monoxenic liquid culture with their bacterial symbionts xenorhabdus nematophila and xenorhabdus bovienii, respectively, the effect of the initial nematode inoculum density on population development and final concentration of dauer juveniles (djs) was investigated. symbiotic bacterial cultures are pre-incubated for 1 day prior to inoculation of djs. djs are developmentally a ...201019597815
influence of soil on the efficacy of entomopathogenic nematodes in reducing diabrotica virgifera virgifera in maize.the use of entomopathogenic nematodes is one potential non-chemical approach to control the larvae of the invasive western corn rootworm (diabrotica virgifera virgifera leconte, coleoptera: chrysomelidae) in europe. this study investigated the efficacy of heterorhabditis bacteriophora poinar (rhabditida: heterorhabditidae), heterorhabditis megidis poinar, jackson and klein (rh., heterorhabditidae) and steinernema feltiae filipjev (rh., steinernematidae) in reducing d. v. virgifera as a function ...201021124754
the influence of humidity on the effect of steinernema feltiae against diapausing codling moth larvae (cydia pomonella l.) (lepidoptera: tortricidae).codling moth (cm) is a serious and global pest of pome fruit. it overwinters in cryptic habitats as cocooned diapausing larvae. field trials with the entomopathogenic nematode steinernema feltiae (rhabditida: steinernematidae) report control of diapausing cm of up to 70%, but results are variable. the objective of this study was to define environmental conditions favouring the performance of the nematodes. cocooned larvae were more susceptible than non-cocooned larvae. s. feltiae was unable to i ...201021539244
hemocyte responses of the colorado potato beetle, leptinotarsa decemlineata, and the greater wax moth, galleria mellonella, to the entomopathogenic nematodes, steinernema feltiae and heterorhabditis bacteriophora.hemocyte encapsulation reactions of infective juveniles of two iranian isolates of the entomopathogenic nematodes, heterorhabditis bacteriophora poinar (rhabditina: heterorhabditidae) and steinernema feltiae filipjev (tylenchina: steinernematidae), were compared in the economic pest colorado potato beetle, leptinotarsa decemlineata say (coleoptera: chrysomelidae), and the greater wax moth, galleria mellonella l. (lepidoptera: pyralidae). the former was a more responsive host than the latter and ...201121867441
controlling the sugar beet fly pegomyia mixta vill. with entomopathogenic nematodes.sugar beet, beta vulgaris l. is a strategic crop of sugar industry in egypt. it is threatened by several insect pests among most important of them is the beet fly pegomyia mixta. this work deals with the biological control of this insect using four entomopathogenic nematodes (epns). the nematodes included steinernema carpocapsae s2, steinernema feltiae, heterorhabditis bacteriophora (hb1-3) and heterorhabditis bacteriophora s1. daily mortality of larvae and pupae of p. mixta were recorded after ...201122696941
the first record of entomopathogenic nematodes (rhabiditiae: steinernematidae and heterorhabditidae) in natural ecosystems in lebanon: a biogeographic approach in the mediterranean region.a survey of entomopathogenic nematodes in lebanon was conducted for the first time during 2008-2009. samples were collected on the coastal strip and in nine vegetation types extending from the coastal line to 3088m above sea level. wooded and herbaceous ecosystems were considered for sampling purposes. a total of 570 samples were taken, out of which 1% were positive for entomopathogenic nematodes. approximately, 15.8% out of the 19 sites sampled revealed entomopathogenic nematodes presence (repr ...201121241704
entomopathogenic nematodes, phoretic paenibacillus spp., and the use of real time quantitative pcr to explore soil food webs in florida citrus groves.quantitative real-time pcr (qpcr) is a powerful tool to detect and quantify species of cryptic organisms such as bacteria, fungi and nematodes from soil samples. as such, qpcr offers new opportunities to study the ecology of soil habitats by providing a single method to characterize communities of diverse organisms from a sample of dna. here we describe molecular tools to detect and quantify two bacteria (paenibacillus nematophilus and paenibacillus sp.) phoretically associated with entomopathog ...201121723288
Purification, molecular characterization and gene expression analysis of an aspartic protease (Sc-ASP113) from the nematode Steinernema carpocapsae during the parasitic stage.Steinernema carpocapsae is an insect parasitic nematode associated with the bacterium Xenorhabdus nematophila. During invasion, this nematode is able to express many proteases, including aspartic proteases. Genes encoding these aspartic proteases have been identified in the EST, and aspartic protease has been found in excretory-secretory products. The total protease was shown to digest blood hemoglobin in a zymogram gel. When the protein was partially purified by pepstatin affinity chromatograph ...201122178695
entomopathogenic nematodes for control of insect pests above and below ground with comments on commercial production.entomopathogenic nematodes (epns) have been utilized in classical, conservation, and augmentative biological control programs. the vast majority of applied research has focused on their potential as inundatively applied augmentative biological control agents. extensive research over the past three decades has demonstrated both their successes and failures for control of insect pests of crops, ornamental plants, trees and lawn and turf. in this paper we present highlights of their development for ...201223482993
directional movement of entomopathogenic nematodes in response to electrical field: effects of species, magnitude of voltage, and infective juvenile age.entomopathogenic nematodes respond to a variety of stimuli when foraging. previously, we reported a directional response to electrical fields for two entomopathogenic nematode species; specifically, when electrical fields were generated on agar plates steinernema glaseri (a nematode that utilizes a cruiser-type foraging strategy) moved to a higher electric potential, whereas steinernema carpocapsae, an ambush-type forager, moved to a lower potential. thus, we hypothesized that entomopathogenic n ...201221945052
an investigation on the chemotactic responses of different entomopathogenic nematode strains to mechanically damaged maize root volatile compounds.entomopathogenic nematodes (epns) respond to a variety of stimuli when foraging. in a laboratory investigation, we tested the chemotactic responses of 8 epn strains (steinernema and heterorhabditis) to three mechanically damaged maize root compounds (linalool, α-caryophyllene and β-caryophyllene). we hypothesized that the epn directional response to the tested volatile compounds would vary among the species and volatile compound and may be related to foraging strategies. the nematodes with an in ...201323562713
evaluation of efficacy of 18 strains of entomopathogenic nematodes (rhabditida) against planococcus citri (risso, 1813) (hemiptera: pseudococcidae) under laboratory conditions.planococcus citri (risso, 1813) (hemiptera: pseudococcidae) is an important plant virus vector in grapevine crops in brazil and other countries. the mealybug grows in roots and leaves of the grapes. entomopathogenic nematodes (epns) are efficient control agents against insects associated to the soil and could be applied with the same equipment used for chemical insecticides. the aim of this study was to select effective epns for controlling p. citri females in laboratory conditions (25±1°c, ur 6 ...201323458234
cold tolerance abilities of two entomopathogenic nematodes, steinernema feltiae and heterorhabditis bacteriophora.entomopathogenic nematodes are effective biological control agents against insect pests but their commercial application is restricted by their limited shelf life. this study applies our knowledge of the cold tolerance of nematodes to this problem and investigates further the cold tolerance mechanisms of steinernema feltiae and heterorhabditis bacteriophora infective juveniles. when frozen using a fast freezing regime these nematodes are moderately freezing tolerant, with a lower lethal temperat ...201323142823
entomopathogenic nematodes in insect cadaver formulations for the control of rhipicephalus microplus (acari: ixodidae).this study evaluated the efficacy of four entomopathogenic nematode (epn) strains in insect cadaver formulations against rhipicephalus microplus and compared the efficacy of the most virulent epns applied in cadavers of galleria mellonella and tenebrio molitor. in the first experiment, infected g. mellonela larvae were used as the source of epns. engorged females of r. microplus were placed in pots filled with soil and different numbers of g. mellonella larvae infected with one of four species o ...201424836639
aggregative group behavior in insect parasitic nematode dispersal.movement behavior of foraging animals is critical to the determination of their spatial ecology and success in exploiting resources. individuals sometimes gain advantages by foraging in groups to increase their efficiency in garnering these resources. group movement behavior has been studied in various vertebrates. in this study we explored the propensity for innate group movement behavior among insect parasitic nematodes. given that entomopathogenic nematodes benefit from group attack and infec ...201424184157
a survey of entomopathogenic nematode species in continental portugal.entomopathogenic nematodes (epn) are lethal parasites of insects, used as biocontrol agents. the objectives of this work were to survey the presence of epn in continental portugal and to characterize the different species. of the 791 soil samples collected throughout continental portugal, 53 were positive for epn. steinernema feltiae and heterorhabditis bacteriophora were the two most abundant species. analysis of epn geographical distribution revealed an association between nematode species and ...201423590880
the influence of insecticides on the viability of entomopathogenic nematodes (rhabditida: steinernematidae and heterorhabditidae) under laboratory order to increase our knowledge on the susceptibility of entomopathogenic nematode (epn) species to agrochemicals, the compatibility of the infective juveniles (ijs) of the epn (steinernema and heterorhabditis) with eight chemical and bio-insecticides was investigated under laboratory conditions. the effect of direct ij exposure to insecticides for 6 and 24 h was tested in a petri dish at 15, 20 and 25 °c.201423873740
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