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The objectives of this study were to quantify the virulence of four entomopathogenic fungal species to pupae of Rhagoletis pomonella (Walsh) (Diptera: Tephritidae) and to determine the potential to combine entomopathogenic fungi (EPFs) and entomopathogenic nematodes (EPNs) for biological control of this pest. The four species of EPFs included Beauveria bassiana (strain GHA), Metarhizium brunneum (strain F52), Isaria javanica (wf GA17), and Isaria fumosorosea (Apopka 97 strain). In laboratory assays, all fungi reduced adult emergence but there were no differences between fungal species. Isaria javanica and M. brunneum were examined further in a EPFs and EPNs bioassay that also included the EPNs Steinernema carpocapsae (ALL strain) and S. riobrave (355 strain). All nematodes and fungi were applied either alone or in combination (fungus + nematode). There were no differences between species within the same entomopathogen group (fungi and nematodes). However, the treatment with S. riobrave resulted in lower R. pomonella emergence than either fungal species. The combination of S. riobrave and I. javanica resulted in the lowest R. pomonella emergence (3%) at fourth-week interval, which was significantly lower than any of the single-agent applications, yet virulence of the other three combination treatments was not different from their respective nematode treatments applied alone. Additive interactions were detected for all fungus–nematode combinations. This study suggests that application of entomopathogenic nematodes and fungi could be an effective option to suppress R. pomonella populations. [ABSTRACT FROM AUTHOR]

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Entomopathogenic nematodes (EPNs) can control pests due to mutualistic association with bacteria that reproduce and kill the host from septicemia, making the environment favourable for nematode development and reproduction. The objective of this study was to identify an EPN isolate collected in eucalyptus cultivation and to determine its pathogenicity with regard to Gonipterus platensis Marelli (Coleoptera: Curculionidae). Four steel-mesh traps with two seventh-instar Galleria mellonella larvae were buried 5 cm deep in the soil in a commercial Eucalyptus plantation. After 7 days, the traps were packed in plastic bags and transported to laboratory to isolate the EPNs using White traps. The obtained nematodes were multiplied in G. mellonella larvae and identified by sequencing their D2/D3 expansion of the 28S rDNA region by polymerase chain reaction (PCR) and specific primers for ITS regions. Steinernema diaprepesi was identified and inoculated into G. platensis pupae at doses of 500, 1000 and 5000 infective juveniles (IJs) to determine its pathogenicity to this pest. At 8 days after inoculation, the mortality rate of the G. platensis pupae was 80% with the lowest concentration and 100% with the others. The emergence of nematodes and the rapid degradation of G. platensis pupae were observed in those inoculated with IJs. The pathogenicity to the G. platensis pupae indicates potential for using this nematode in the integrated management of this insect.

The emphasis of this review is on the use and potential of entomopathogenic nematodes (EPNs) as biological control agents in sustainable food production across a wide range of agricultural and other commodities. To aid with the understanding of the potential of EPNs in sustainable food production, this review also provides overviews on EPN biology and ecology, mass production and application technology, and interactions with other management tools. First discovered in the 1920s, their commercialization as biopesticides in the 1980s was accompanied and followed by an exponential growth in research on their application, biology, and ecology, followed by a further expansion in more basic research areas since the mid-2000s. This review summarizes significant progress made in the research and application of EPN in insect pest management in important food crops including orchards, small fruit, maize, vegetables, tuber crops, greenhouses, and mushrooms. Significant factors affecting the success of EPN commercialization are also discussed. A growing interest in alternatives to synthetic insecticides and in organic agriculture opens opportunities for EPNs, but EPNs will need to be further improved with respect to efficacy, reduced costs, and ease of use. Moreover, their potential to recycle in host populations beckons to be further exploited for long term pest suppression.

Virachola livia (Lepidoptera: Lycaenidae) and Ectomyelois ceratoniae (Lepidoptera: Pyralidae) are the key pests of pomegranates in Saudi Arabia that are managed mainly using broad-spectrum pesticides. Interactions between the entomopathogenic nematodes (EPNs) Steinernematids, and Heterorhabditids, and their entomopathogenic bacterial symbionts (EPBs) have long been considered monoxenic 2-partner associations responsible for killing insects and, therefore, are widely used in insect pest biocontrol. However, there are limited reports identifying such organisms in Taif, Saudi Arabia. The current study aimed to identify the EPNs and their associated bacteria isolated from Taif, Saudi Arabia, and evaluate their biocontrol potential on third instar larvae of V. livia and E. ceratoniae under laboratory conditions. A total of 35 EPN isolates belonging to Steinernema (20) and Heterorhabditis (15) were recovered from 320 soil samples. Twenty-six isolates of symbiotic or associated bacteria were isolated from EPNs and molecularly identified as Xenorhabdus (6 isolates), Photorhabdus (4 isolates), Pseudomonas (7), or Stenotrophomonas (9). A pathogenicity assay revealed that Steinernema spp. were more virulent than Heterorhabditis spp. against the two pomegranate insects, with LC50 values of 18.5 and 13.6 infective juveniles (IJs)/larva of V. livia for Steinernema spp. and 52 and 32.4 IJs/larva of V. livia for Heterorhabditis spp. at 48 and 72 h post-treatment, respectively. Moreover, LC50 values of 9 and 6.6 IJs/larva (Steinernema spp.) and 34.4 and 26.6 IJs/larva (Heterorhabditis spp.) were recorded for E. ceratoniae larvae at 48 and 72 h post-treatment. In addition, the EPB Stenotrophomonas maltophilia CQ1, isolated from Steinernema spp., surpassed Pseudomonas mosselii SJ10, associated with Heterorhabditis spp., in their ability to kill V. livia or E. ceratoniae larvae within 6 h post-application, resulting in 100% mortality in both insects after 24 and 48 h of exposure. We conclude that either application of EPNs’ IJs or their associated EPBs could serve as potential biocontrol agents for V. livia and E. ceratoniae.

An overview is given on several aspects of evolutionary history, ecology, host plant use, and pharmacophagy of Diabrotica spp. with a focus on the evolution of host plant breadth and effects of plant compounds on natural enemies used for biocontrol of pest species in the group. Recent studies on each aspect are discussed, latest publications on taxonomic grouping of Diabrotica spp., and new findings on variations in the susceptibility of corn varieties to root feeding beetle larvae are presented. The further need for in-depth research on biology and ecology of the large number of non-pest species in the genus is pointed out.

Abstract Mosquitoes (Diptera: Culicidae) are among the most important of the pests in urban entomology, and they not only disturb people but they are also an important health hazard as they are diseases’ vectors. The biological control methods against this pest, which is difficult to fight off, have recently gained importance. A total of five different entomopathogenic nematodes (EPNs), Steinernema feltiae (Aydın isolate), S. carpocapsae (Karadeniz isolate), and Heterorhabditis bacteriophora (Aydın isolate) isolated from Turkey and S. feltiae (KG3) and H. bacteriophora (KG81) isolated from Kyrgyzstan, were tested against the mosquito species Culex pipiens L. (Diptera: Culicidae) larvae under laboratory conditions. The experimental nematode suspensions were determined as 500, 1000, and 1500 IJs ml−1. The mortality rates in the trial were recorded after 24, 48, 72, 96, and 120 h. Dead mosquitoes were dissected under a microscope and confirmed to have died by the EPNs. Larval mortality was observed in all EPN species compared to the control group. H. bacteriophora (KG81) and S. carpocapsae isolates were found to be the most effective isolates with 100% larval mortality. The other isolates were H. bacteriophora (Aydın isolate) (70%), S. feltiae (KG3) (66.67%), and the most ineffective isolate S. feltiae (Aydın isolate) (13.3%).

Abstract The black cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae) is considered to be one of the serious polyphagous pests that spend a large part of its life in the soil environment, where many microorganisms live including entomopathogenic nematodes (EPNs) (Rhabditida: Steinernematidae and Heterorhabditidae). EPNs have been long used for suppressing the soil-dwelling insects like cutworms and are successful biological control agent against A. ipsilon larvae. In the present study, the efficacy of local EPNs isolates against the fourth larval instar of A. ipsilon was evaluated at different concentrations (10, 25, 50, 100 IJs/larva/Petri dish and 25, 50, 100 IJs/cm2 soil) in two different experiment environments including filter papers in Petri dishes and soil in plastic containers under laboratory conditions at 25 ± 1 °C. Larval mortalities of A. ipsilon were recorded first, second, third, and fourth day post inoculation where the mortality rates increased by increasing the concentrations. The maximum mortality rate (100%) was reached within 2 days after inoculation, inoculating the Heterorhabditis bacteriophora FLH-4-H and H. indica 216-H isolates at concentrations of 50 and 100 IJs/cm2, in the plastic container experiment. The highest mortality rate (90%) was obtained by Steinernema carpocapsae E76-S isolate at a concentration of 100 IJs/larva/Petri on the fourth day after inoculation, in the Petri dish experiment. The lethal concentration values (LC50 and LC90) of the A. ipsilon larval population were 52 IJs and 129 IJs, respectively, for S. feltiae E76-S isolate in the Petri dish tests. In the plastic container experiment, the lowest LC50 and LC90 values found to be 17 IJs and 23 IJs, respectively, for H. bacteriophora FLH-4-H isolate. The results showed that all indigenous EPN isolates had good potentials in the management of A. ipsilon.

Abstract The goal of this work was to investigate the effect of gamma irradiated entomopathogenic nematode EPN; Steinernema scapterisci on third and fourth larval instars of Culex pipiens under laboratory conditions and its effect on the elemental composition of the treated larvae. Results showed that normal and irradiated tested nematodes differed in their efficacies against third and fourth larval instars. The mortality rates increased with increasing the nematode concentration and the period after treatment, in most cases the mortality in fourth instar larvae was more than in third instar larvae under the same treatments, and the percentage of mortality in irradiated nematodes was more than that in unirradiated ones. Studying the elemental composition showed that phosphorus (P) was the highest concentration in untreated larvae or those treated with normal S. scapterisci, while calcium (Ca) was the highest concentration in gamma irradiated S. scapterisci. The lowest concentration in untreated larvae was zinc (Zn), while copper (Cu) was the lowest concentration in unirradiated and 2 Gy gamma irradiated S. scapterisci. In conclusion, the gamma irradiation of S. scapterisci enhanced its efficacy against C. pipiens, therefore it could serve as safe control method for C. pipiens.

Abstract Two entomopathogenic nematodes (EPNs) Heterorhabditis indica and Steinernema carpocapsae were tested against the armyworm, Spodoptera litura (F.) (Lepidoptera: Noctuidae). Also, their compatibility with spinosad (Tracer® 240SC) was assessed under laboratory conditions. In study I, compatibility test was performed to evaluate the viability of nematodes at different concentrations of spinosad. None of the concentrations was observed as toxic against both EPNs. The highest concentration (800 ppm) of the spinosad showed 14% mortality in H. indica juveniles and 13% in S. carpocapsae 48 h post-treatment. In study II, the spinosad and the EPN mixtures showed that both EPNs enhanced the efficacy of spinosad against S. litura larvae. The highest mortality rates (80.0 and 76.6%) in the second instar larvae indicated a synergistic effect (χ 2 = 39.69 and 7.02) 48 h post-treatment, with infective juveniles (IJs) of S. carpocapsae and H. indica, respectively, with the highest concentration of spinosad. In the case of the third instar larvae, a synergistic effect (χ 2 = 16.73) was observed in H. indica and the highest concentration of spinosad, while other treatments showed additive efficacy of the EPNs. After 96 h, all treatments exhibited synergistic effect, except when H. indica was applied at the lowest concentration of spinosad. However, these combination treatments need to be tested further with EPNs under field conditions to confirm their efficacy.

Abstract The ability of entomopathogenic nematodes to suppress larval populations of the white grub, Leucopholis lepidophora Blanchard (Coleoptera: Scarabaeidae), infesting the areca nut palm (Areca catechu) was investigated under field conditions over a 2-year period (2015–2017). Heterorhabditis indica at two application rates (1.7 × 105 and 3.5 × 105 IJs palm−1) caused higher percentage reduction of L. lepidophora larvae than Steinernema abbasi and chlorpyrifos. Chlorpyrifos-treated plots caused higher percentage of reduction of the grub larvae than S. abbasi at the lowest rate (1.7 × 105 IJs palm−1). However, S. abbasi at 3.5 × 105 IJs palm−1 performed at least equally well than the chlorpyrifos treatment. The kernel yield from H. indica-treated plots at 3.5 × 105 IJ palm− 1 was 85.4% higher than those from water control and 33.3% higher than that in the chlorpyrifos treatment. The kernel yields varied significantly among different treatments. The cost-benefit analysis showed that H. indica is a promising biocontrol agent for the management L. lepidophora control in areca nut field.

Abstract Himachal Pradesh is a northern state of India and is situated to the southern of the mighty Himalaya. The agro-climatic conditions are conducive for the production of off-season vegetables. Biological control by entomopathogenic nematodes (EPNs) is one of the alternatives to manage the turnip moth, Agrotis segetum (Denis & Schiffermuller) (Lepidoptera: Noctuidae). The present study was, therefore, undertaken with the objective to assess the virulence of local EPN isolates from Himachal Pradesh, Heterorhabditis sp., against pests to minimize the use of insecticides during crop protection. Against L3–L5 of A. segetum, Heterorhabditis indica was found highly effective, resulting in 33.33–93.33% mortality at 40 infective juveniles (IJs)/larva after 96 h of treatment. Among local isolates, Heterorhabditis sp. (HSG) influenced maximum mortality of L3 and L4, whereas in L5, H. bacteriophora (HRJ) influenced maximum mortality. The sensitivity of L3 to different EPNs was (7.0–16.6%) higher than that of L4. In soil bioassay carried out against L4 of A. segetum, H. bacteriophora (HRJ) was found highly effective, followed by Heterorhabditis sp. (HKM) and Heterorhabditis sp. (HSG) at 10,000 IJs/kg of soil. The mortality varied from 78.33 to 81.67% with local isolates after 7 days of treatment. The results suggested that EPNs can be used as one of the components for managing A. segetum under field and greenhouse conditions to reduce over dependence on insecticides.

Abstract The rice white tip nematode, Aphelenchoides besseyi, is the primarily important seed-borne pest of rice and was first recorded in Turkey in 1995. These biological agents, such as an entomopathogenic fungus (EPF), entomopathogenic nematodes (EPN), and bacterial supernatants, have been used against other plant parasitic nematodes but as far as not against A. besseyi. Accordingly, the EPF species, Purpureocillium lilacinum, and the four EPN species, Heterorhabditis bacteriophora, Steinernema carpocapsae, S. glaseri, and S. feltiae, and the supernatant of the two bacterial symbionts, Photorhabdus luminescens and Xenorhabdus bovienii, were used against A. besseyi. In addition, infected Galleria mellonella cadavers with S. feltiae were evaluated as a biological agent to the white tip nematode. The percentage of observed white tip symptoms, decrease in kernel numbers in the panicles, and decrease in panicle weight were evaluated. Evaluation of these parameters showed that X. bovienii supernatant, S. feltiae infective juveniles, and P. lilacinum at 108 conidia ml−1 consistently suppressed the A. besseyi population.

Abstract Little is known about element contents in the entomopathogenic nematodes despite their vital role in the growth and development of all organisms. Ten element contents of seven nematode isolates were determined. No significant differences were observed in concentrations of aluminum (Al), chromium (Cr), and lead (Pb) among all the studied nematode isolates, while significant differences of cadmium (Cd), selenium (Se), zinc (Zn), and manganese (Mn) concentrations among isolates were found. All isolates related to Heterorhabditidae family contained significantly higher copper (Cu), iron (Fe), and cobalt (Co) concentrations than isolates related to Steinernematidae family of entomopathogenic nematode (EPN). In all of tested isolates, the content of Cu was the highest and that of Se was the lowest. The concentrations of the studied elements were in the following descending order: Cu > Fe > Co > Mn > Zn > Pb > Cr > Cd > Al > Se. It is suggested that Photorhabdus bacteria associated with Heterorhabditis spp. of EPN accumulate Cu, Fe, and Co for activation of their metalloenzymes to enhance their virulence potential.

With this study, the presence of entomopathogenic nematodes (EPN) in 15 villages (Ulaş, Taşlıçiftlik, Söngüt, Büyükbağlar, Uğrak, Tahtoba, Dayılıhacı, Çördük, Kızılköy, Bakışlı, Ballıdere, Çöreğibüyük, Gaziosmanpaşa, Günevi, Akyamaç and 2 towns (Güryıldız, Emirseyit) of Tokat province where alfalfa was cultivated intensively was investigated between June-October 2016. For this purpose, 58 soil samples were taken and obtained 10 EPN isolates by trapinsect method. As a result of the morphological and molecular diagnosis, 8 of them were defined as Steinernema carpocapsae, one isolate as S.feltiae and one isolate as Heterorhabditis bacteriophora. This paper is the first report showing the occurrence of EPNs in alfalfa fields in Turkey. [ABSTRACT FROM AUTHOR]

A survey of entomopathogenic nematodes (EPN) was conducted in Morocco during 2015 and 2016 in three regions with varying topography, climate and vegetation (Meknès-El Hajeb, Ifrane and Tafilalet). EPN were isolated from 14 of 169 soil samples (8%). Molecular and morphological techniques were used for species determination. Nine samples contained heterorhabditids and five samples contained steinernematids. Eight heterorhabditids were identified as Heterorhabditis bacteriophora Poinar 1976, two steinernematids as Steinernema feltiae (Filipjev, 1934), three as belonging to the S. feltiae-group, and one as an unidentified isolate (Heterorhabditis sp.) which gives dark burgundy colour for G. mellonella cadavers. These EPNs were collected mainly from agricultural soils rather than natural habitats, with potential adaptation to specific geography, climate and soil conditions (texture, pH and organic matter content), including six EPN isolates from heavy soils. These data demonstrate that EPN are present in Moroccan soils but at relatively low frequency, so opportunity exists to augment these populations to gain biological control benefits. [ABSTRACT FROM AUTHOR]

The sycamore lace bug Corythucha ciliata (Say) (Hemiptera: Tingidae) is an invasive species native to North America that has been introduced in Europe and infests various species of the ornamental plane trees (Platanus sp.). This study aims to test the susceptibility of C. ciliata nymphs and adults to different doses of three entomopathogenic nematode species under laboratory conditions. Heterorhabditis bacteriophora did not infect C. ciliata nymphs, while Steinernema carpocapsae exhibited higher virulence (77–96% at 132 IJs cm−2) to all stages of C. ciliata than S. feltiae (10–39% at 132 IJs cm−2). Steinernema carpocapsae was significantly more virulent at the highest dose (132 IJs cm−2) than at the medium (50 IJs cm−2) and lowest (25 IJs cm−2) doses. After 6 h and 12 h of nymph exposure to S. carpocapsae, this nematode caused 39% and 47% mortality at 132 IJs cm−2, respectively. The virulence of S. carpocapsae was significantly lower at 15 °C than at 25 °C (75.5% and 96% adult mortality, respectively) but was still more virulent than S. feltiae at both temperatures (29.5% and 39% adult mortality, respectively). These results show that S. carpocapsae could constitute a viable biological control agent for C. ciliata. [ABSTRACT FROM AUTHOR]

The weevil Phyrdenus muriceus Germar (Coleoptera: Curculionidae) is an emergent pest of eggplant (Solanum melongena L.) crops in the humid Pampa of Argentina. Entomopathogenic nematodes (EPNs) constitute an effective and environmentally safe strategy within integrated pest management. The efficacy of a native EPN Heterorhabditis bacteriophora SUP isolate for the control of P. muriceus was evaluated. Larvae and adults were susceptible to the nematode in laboratory assays. Field evaluations indicated a slight reduction of P. muriceus populations, evidenced after a second application by a decrease of the foliar damage in the eggplant crops. Adults of P. muriceus parasitized by H. bacteriophora were observed in the field one month after the second application. The present study is the first assessment of EPNs against P. muriceus under field conditions, and the first report of their use in the humid Pampa, one of the major agricultural areas of Argentina. [ABSTRACT FROM AUTHOR]

Wireworms are destructive soil inhabiting polyphagous pests in the Pacific Northwest and Intermountain region of the United States. Continuously increasing wireworm populations and damage in small grain crops such as spring wheat in Northern Great Plains has become a challenge for growers. Due to unavailability of effective control measures, alternative methods, including biological control agents such as entomopathogenic nematodes (EPNs) are needed. Native/indigenous EPN species are expected to have better potential than exotic species to control the local insect pests. Two Montana native EPN species (Steinernema feltiae and Heterorhabditis bacteriophora) were tested against, Limonius californicus (Coleoptera: Elateridae) in laboratory and shade house studies. In the laboratory bioassay, two isolates of S. feltiae at the rate of 28,000 IJs/five larvae killed 48–50% of the insects within 4 wk. Heterorhabditis bacteriophora was not able to cause >30% L. californicus larval mortality. None of the two isolates of S. feltiae performed well against L. californicus when tested in different soil types. Similarly, two isolates of S. feltiae that were tested killed only 20–25% wireworms in a shade house trial that did not differ significantly from the control treatment. Four weeks after EPN treatment in the shade house trial, the percentage of wheat plant damage from L. californicus ranged from 30 to 40% in the presence of S. felitae , not differing statistically from control. These results suggest that S. felitae have limited potential in managing wireworm populations. [ABSTRACT FROM AUTHOR]

The effects of entomopathogenic nematodes EPN (Steinernematidae and Heterorhabditidae) and fungi EPF (Beauveria bassiana) strains were evaluated in laboratory assays against larvae of four xylophagous pests: the Asparagus moth Parahypopta caestrum, the European goat moth Cossus cossus, the pine longhorn Arhopalus syriacus and the black Buprestid Capnodis tenebrionis. Due to their biology and ethology, these insects may be included in the category of pests residing in cryptic habitats. The control of these species is considered difficult, due to the inability of chemical pesticides to penetrate the cryptic habitats and reach the targets. The pathogenicity of the entomopathogenic nematodes and fungi was tested in vitro against the pests. Two experimental models were considered and aimed to imitate the natural environment of the pests, in Petri dishes filled with plant material and inside wood galleries respectively. Main results showed that the majority of the tested strains of nematodes and fungi affected the insects' survival rate. Steinernema feltiae and B. bassiana caused the highest percentage of larval mortality (80–100%). Considering the lack of effective chemical control means, the microbial control of the xylophagous pests by EPN and EPF reveals promising perspectives. Nematodes and fungi are able to penetrate the cryptic habitats because they are living organisms and may be horizontally transmitted by infected hosts. The distribution of EPF as preventive control method and the injection of EPN suspensions to reach and infect the larvae inside the wood galleries can be a combined sustainable control system. [ABSTRACT FROM AUTHOR]

The potential of native entomopathogenic nematodes for the control of the brown marmorated stink bug Halyomorpha halys was evaluated in experimental trials in Georgia. Two Georgian strains of Heterorhabditis bacteriophora (HRB, GEO) and Steinernema borjomiense and two Italian strains of H. bacteriophora (HRB, IT) and S. apuliae were used in laboratory assays (22°C and 80% RH) at concentrations of 1000, 500 and 200 infective juveniles (IJs) per adult H. halys. The mortality of tested insects was estimated from the third day after treatment. Differences in mortality of the tested insect were observed between Georgian and Italian strains. At the highest concentration (1000 IJs/adult), mortality (%) of H. halys induced by Georgian strains HRB and S. borjomiense was 53.3 and 40, respectively, at 500 IJs/adult 40 and 33.3, and at 200 IJs/adult 33.3 and 13.3, respectively. Italian strains HRB (IT) and S. apuliae proved more suppressive against the tested insects, with mortality rates of 95.5 and 60, 93.3 and 40 and 73.3 and 33.2%, at concentrations of 1000, 500 and 200 IJs/adult of H. halys, respectively. The present study provides further insights in selection of promising EPN strains to be used against this harmful insect pest, although further studies to test their efficacy under field conditions are needed. [ABSTRACT FROM AUTHOR]

Above‐ground plant tissues produce characteristic blends of volatile compounds in response to insect herbivory. These herbivore‐induced plant volatiles (HIPVs) function in plant defence and mediate foraging decisions by herbivores and their natural enemies. The ecological roles of HIPVs as foraging cues for different trophic levels highlight an important conflict for herbivores that need to locate suitable host plants while avoiding competition and predation.Plant roots also emit HIPVs following herbivory, but our understanding of root‐produced volatiles and their ecological functions in soil environments remains limited. Moreover, recent studies have documented the effects of temporal dynamics of plant volatile production on ecological interactions, but little is known about how root HIPVs change throughout herbivory or the resulting ecological implications from such changes.In this study, we examined the roles of HIPVs from roots of cucumber plants Cucumis sativus as foraging cues for a specialist herbivore, striped cucumber beetle Acalymma vittatum and its natural enemies, entomopathogenic nematodes (EPNs). We predicted HIPVs from A. vittatum‐damaged roots would attract EPNs, while repelling conspecific larvae that avoid competition, induced plant defences and increased risk of predation by EPNs. To capture the temporal dynamics of root HIPVs, we determined how HIPV‐mediated interactions change over time with sustained herbivory.Initially (after 24 hr), A. vittatum herbivory on C. sativus, or mechanical wounding, induced greater production of root volatiles. These root HIPVs recruited EPNs and repelled foraging A. vittatum larvae, although larval performance was not affected by prior damage. Sustained (7 days) herbivory by larvae reduced HIPVs to levels indistinguishable from undamaged control roots while mechanically damaged roots continued to produce higher levels of volatiles. Attenuation of HIPVs impaired indirect defence responses of C. sativus by reducing recruitment of EPNs and deterrence of A. vittatum larvae.These results suggest that root HIPVs function as honest signals that indicate the presence of herbivores, induction of indirect plant defences and increased risk of predation by natural enemies. However, some herbivores may overcome this line of plant defence by attenuating production of HIPVs and thus altering the outcomes of subsequent interactions among plants, herbivores and natural enemies. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

The banded fruit weevil (BFW), Phlyctinus callosus (Coleoptera: Curculionidae), is a major indigenous pest of deciduous fruits and grapevine in the Western Cape province of South Africa. Entomopathogens are effective in controlling soil-borne and above-ground stages of insect pests. Soil samples were collected from deciduous fruit orchards and vineyards in the Western Cape, baited with mealworms to isolate entomopathogenic nematodes (EPNs) and entomopathogenic fungi (EPF), which were identified using molecular techniques and assessed for their potential as biocontrol agents of BFW adults. A correlation analysis was performed to determine the effect of soil parameters on the presence of the entomopathogens. EPNs were trapped in 12 (17 %) samples, while Heterorhabditis bacteriophora and Heterorhabditis safricana were the only two species isolated. EPF were isolated from 26 (37 %) samples baited, with 14 fungal isolates identified as Beauveria bassiana (Cordycipitaceae) and 12 identified as Metarhizium anisopliae (Clavicipitaceae) complex. Heterorhabditis bacteriophora (53 %) gave significantly higher (P < 0.05) control of adult BFW than H. safricana (37 %). Metarhizium anisopliae (79 %) gave significantly higher (P < 0.05) control of BFW adults than B. bassiana (63 %). Organic matter, magnesium and phosphorus had a negative relationship with the occurrence of EPNs. A negative relationship was also reported between the occurrence of EPF, and organic matter and potassium. The results indicated that soils from the deciduous fruit orchards and vineyards from the Western Cape contain both EPNs and EPF with potential to be used in an integrated pest management system against soil-borne and above-ground stages of BFW [ABSTRACT FROM AUTHOR]

Essential oils are being increasingly utilised as a biorational element in integrated pest management regimes. Whereas there has been much research on the effects of these oils on mortality and behaviour of pestiferous molluscs, insects and nematodes, there has (to the present authors' knowledge) been no research into their effects on the mortality and behaviour of beneficial nematodes. We address this lacuna by conducting laboratory assays on the behaviour (thrashing assays) and mortality of 13 essential oils plus controls of Tween and water on the malacophagous nematode Phasmarhabditis hermaphrodita and two species of entomopathogenic nematodes, namely: Steinernema feltiae and Heterorhabditis bacteriophora. Mortality results showed an "all or nothing" response with only three oils—pine oil, peppermint and lemongrass—displaying intermediate mortalities. Also, toxicity of essential oils was conserved across phylogenetically quite distinct beneficial nematode species with oil toxicity largely being repeated across the three beneficial nematodes. Thrashing assays confirmed the toxic effects of certain oils. We recommend that the effects of essential oils be tested on beneficial organisms in ecosystems before choices are made over which oils should be used. The present paper highlights some oils which are not toxic to beneficial nematodes but may affect their behaviour. Research should focus on these oils as part of a biorational control programme for pestiferous molluscs and insects. [ABSTRACT FROM AUTHOR]

The number of sustainable agriculture techniques to improve pest management and environmental safety is rising, as biological control agents are used to enhance disease resistance and abiotic stress tolerance in crops. Here, we investigated the capacity of the Photorhabdus luminescens secondary variant to react to plant root exudates and their behavior toward microorganisms in the rhizosphere. P. luminescens is known to live in symbiosis with entomopathogenic nematodes (EPNs) and to be highly pathogenic toward insects. The P. luminescens-EPN relationship has been widely studied, and this combination has been used as a biological control agent; however, not much attention has been paid to the putative lifestyle of P. luminescens in the rhizosphere. We performed transcriptome analysis to show how P. luminescens responds to plant root exudates. The analysis highlighted genes involved in chitin degradation, biofilm regulation, formation of flagella, and type VI secretion system. Furthermore, we provide evidence that P. luminescens can inhibit growth of phytopathogenic fungi. Finally, we demonstrated a specific interaction of P. luminescens with plant roots. Understanding the role and the function of this bacterium in the rhizosphere might accelerate the progress in biocontrol manipulation and elucidate the peculiar mechanisms adopted by plant growth-promoting rhizobacteria in plant root interactions. [ABSTRACT FROM AUTHOR]

Aedes aegypti, is a major vector of several human diseases such as dengue, yellow fever, chikungunya and Zika virus. Multiple strategies are adopted for its control including eradication of mosquito breeding sites by improving water storage and solid waste disposal as well as treating breeding sites with chemical insecticides. However, continuous use of insecticides has resulted in development of insecticide resistance in Ae. aegypti. This study explores the potential biocontrol of Ae. aegypti by the use of commercial entomopathogenic nematodes, namely Heterorhabditis bacteriophora, H. downesi, H. megidis, Steinernema carpocapsae, S. feltiae and S. kraussei. The pathogenic effect of nematodes (concentrations 10, 250, 500 and 1,000 infective juveniles (IJs)) was assessed against third instar Ae. aegypti in multi-well culture plates for 3 days. The evaluated nematode species were pathogenic to Ae. aegypti, however, their virulence varied significantly. Heterorhabditis bacteriophora and S. carpocapsae were most virulent causing 90-100% mortality at 100 IJs per larva, whereas H. megidis and S. kraussei showed least virulence causing 40-60% mortality. Heterorhabditis downesi and S. feltiae had intermediate virulence. Third instar Ae. aegypti indiscriminately overfeed nematodes triggering melanisation but ingested nematodes overcome the defence system resulting in killing the larvae and reproduced within them. Some of the nematodes were melanised, suggesting a strong humoral defence response by Aedes, nevertheless, with variable degree of melanisation. The melanisation did not stop nematode from multiplying and killing Aedes larvae and thus, they have potential to be developed into a novel strategy for Ae. aegypti control. [ABSTRACT FROM AUTHOR]

The Oriental armyworm, Mythimna separata Walker (Lepidoptera: Noctuidae) is a major pest of cereal crops, and its outbreaks result in complete crop loss. In this study, we tested the pathogenicity and reproductive potential of indigenous entomopathogenic nematodes (EPNs), Heterorhabditis indica Poinar, Karunakar, & David NBAIIH38, Steinernema abbasi Elawad NBAIISa01, S. carpocapsae Weiser NBAIISc05 and S. siamkayai Stock, Somsook and Reid NBAIRS92 against larval and pupal stages of M. separata under laboratory conditions. Steinernema carpocapsae caused significantly greater mortality in second‐ and fourth‐instar larval stages than other EPNs species. Steinernema carpocapsae caused greatest mortality 100% in larval stages and 75% in pupal stages. Significant differences were observed in the lethal concentration values (LC50 and LC90) of EPNs species against different stages of M. separata. Differences in penetration and multiplication in the fourth‐instar larval stages of M. separata were observed amongst the EPNs species. However, further studies are needed to reveal the field performance of EPN isolates tested to be included in the IPM programme of M. separata. [ABSTRACT FROM AUTHOR]

Entomopathogenic nematodes (EPNs) are being used for the management of insect pests occurring in both agricultural and horticultural crops. But native EPNs are reasonably more efficacious in controlling insect pests than introduced EPNs species because they are adapted to local environmental conditions and insect pests. Therefore, in the present study, a survey was conducted to isolate EPNs at 4 districts of Purvanchal Region and 1 district of Bundelkhand Region of Uttar Pradesh, India, between 2016 and 2017 years. Out of 130 soil samples, EPNs were recovered from 3 soil samples (2.3%). Morphological characters examination and ITS-rDNA region revealed that the 3 EPNs such as Steinernema sp. (IIVR JNC01 strain) Steinernema sp. (IIVR JNC02 strain), and Steinernema sp. (IIVR EPN03 strain) are belonging to Steinernema siamkayai. Further pathogenicity of all these strains was tested on Galleria mellonella Linnaeus and the most effective strain was used to determine the biocontrol potential against lepidopteran and coleopteran pests of major vegetable crops in comparison to commercially available Heterorhabditis indica (NBAIIH38 strain). Results revealed that S. siamkayai (IIVR JNC01 strain) caused 100, 100, and 85%, mortality of 3rd instar larvae of Spodoptera litura Fabricius, Spilosoma obliqua Walker, and Spoladea recurvalis Fabricius, respectively. Similarly, S. siamkayai (IIVR JNC01 strain) caused 92.5% mortality of 2nd instar grubs of Myllocerus subfaciatus Gurein under laboratory conditions. The present study revealed that EPNs commonly present at Purvanchal and Bundelkhand regions of Uttar Pradesh and S. siamkayai (IIVR JNC01 strain) isolated from the Bundelkhand Region showed a good biocontrol potential against major insect pests of vegetable crops. [ABSTRACT FROM AUTHOR]

Trimen's false tiger moth, Agoma trimenii (Lepidoptera: Agaristidae), recently developed as a pest of grapevine in the Northern Cape and Limpopo (Groblersdal area) provinces of South Africa. Little is known about the biology of A. trimenii and control options are lacking. The aim of this study was to test the susceptibility of A. trimenii larvae and pupae to two locally isolated entomopathogenic nematodes (EPNs), Steinernema yirgalemense and Heterorhabditis noenieputensis, and two commercially available entomopathogenic fungi (EPF), Metarhizium anisopliae and Beauveria bassiana, under laboratory conditions. Larvae and pupae were screened for pathogenicity of the two nematode species, using a concentration of 100 infective juveniles (IJs)/50 µl of water. After 48 h, 100% mortality of the larval stage was found. However, no pupae were infected with EPNs. Larvae and pupae were screened for pathogenicity of the two EPF isolates by means of a dipping test, at a concentration of 0.2 ml/500 ml water and 0.5 g/500 ml water, respectively. Five days post-treatment, 100% larval mortality was recorded in comparison with no deaths in the controls. Overt mycosis was only observed in the case of M. anisopliae. However, in the case of pupae, no mortality was observed for both the nematode and the fungal applications. In future studies, the prepupal soil stage of A. trimenii should be screened for susceptibility to EPNs and EPF. The results of this study indicate the excellent potential of EPNs and EPF as biological control agents against the larvae of A. trimenii, especially for application to small areas with high infestation, without disrupting an integrated pest management programme. [ABSTRACT FROM AUTHOR]

Copyright of Progress in Plant Protection is the property of Institute of Plant Protection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Entomopathogenic nematodes (EPNs) are among the frequently used and commercialized bio-pesticides. However, they are restricted in their infectivity, persistence, storage, and cost of production. One of the methods used to improve this is a continuous search for new isolates with significant behavioral and physiological characteristics. A novel EPN isolate, Heterorhabditis zealandica strain ETL, isolated from South Africa (GPS co-ordinates − 24.849721 and 28.336980) is described and studied against late-instar of Galleria mellonella (L.) and Tenebrio mollitor (L.) larvae. The morphological and molecular studies indicated this isolate as a Heterorhabditis strain. The comparison of sequences of the internal transcribed spacer (ITS) region, the 18S rRNA gene, and the D2-D3 region of the 28S rRNA gene with available sequences of other described species within the genus indicate the isolate as a new Heterorhabditis zealandica strain. The phylogenetic analysis of the sequence data places strain ETL, closest to H. zealandica strain Bartow (GU174009) in the Heterorhabditis group. This EPN was lethal to G. mellonella and T. mollitor; as infections occurred within 24–96 h. Fifty percent of the larvae population were killed within 24 h and 100% after 96 h. [ABSTRACT FROM AUTHOR]

Males sometimes engage in fights over contested resources such as access to mates; in this case, fighting behaviour may be adjusted based on the value they place on the females. Resource value (RV) can have two components. First, males can assess the quality of females, which constitutes an objective assessment of RV. Second, internal state such as previous mating experience can also influence motivation to fight thus constituting a subjective assessment of RV. If mating opportunities are scarce and available females have a major impact on the lifetime reproductive success of males, then fighting can be fatal; in this situation it is uncertain whether males would adjust fighting behaviour based on RV. We found that both female quality, that is, virginity (objective component of RV) and male mating status (subjective component of RV) influenced fighting intensity between males of the entomopathogenic nematode Steinernema longicaudum which engage in lethal fights. Male nematodes were more likely to engage in fighting and fought longer and more frequently in the presence of virgin (high-quality) females than in the presence of mated (lower-quality) females. Male mating status was also found to influence fighting behaviour: mated males were the winners in staged fights between mated and virgin males. Mated males may have superior fighting ability (greater resource-holding potential), but RV asymmetries between mated and virgin males cannot be excluded. Males were more likely to win when they were resident, but we did not find a significant interaction effect between male mating and residency status. • Male entomopathogenic nematodes frequently fight to death for access to mates. • In dyadic contests, males fight more intensely over high-quality (virgin) females. • In dyadic contests, mated males win over virgin males. • In dyadic contests, resident males win over intruder males. [ABSTRACT FROM AUTHOR]

In this study the occurrence of entomopathogenic nematodes (EPNs) was determined in three senatorial districts of Osun State in relation to soil texture, vegetation, moisture and pH. A total of 110 soil samples were randomly collected from various cultivated fields in different locations. The soil samples were baited twice using last instar larvae of the Galleria mellonella (greater wax moth) for presence of entomopathogenic nematodes. Four EPN isolates were recovered viz., Heterorhabditis indica, Heterorhabditis bacteriophora, Steinernema karii and Steinernema wesieri. Of a total of 110 soil samples examined, EPNs were found in 90.90% soil samples, they belonged to the genera Steinernema and Heterorhabditis. Steinernema spp. was found prevalent in both cultivated and undisturbed soils. Frequency of occurrence of EPNs in the sampled soils from the different senatorial zones was determined: soil samples from the Central zone recorded the lowest prevalence 87.50% while the soil samples from Western senatorial zone revealed 91.43% presence of the EPNs. The highest frequency of occurrence of EPNs- 94.29% was recorded in the soil samples from Eastern senatorial zone. Nematode distribution and frequency was found to be related to soil pH (pH<4.5 to pH>7.2) and soil moisture. This is the first report of these nematodes from Osun State, Nigeria. [ABSTRACT FROM AUTHOR]

Entomopathogenic nematodes (EPNs) are a group of biological control agents that are characterized by their ability to search for hosts, safety to non-target insects and environment, and their ability to be used combined with agricultural chemicals. The objectives of this study were to isolate EPNs from agricultural soil in Egypt and study their virulence against the great wax moth, Galleria mellonella L. (Lepidoptera: Pyralidae), for further use in biological control program. Two out of 20 soil samples collected from orchards cultivated with olives and mango were positive for the presence of EPNs, using the Galleria baiting technique. The positive soil samples were sandy clay loam. Sequencing of the internal transcribed spacer (ITS) region indicated that the isolates obtained belong to Heterorhabditis indica. The ITS sequences were submitted to the National Center for Biotechnology Information (NCBI) and registered under the accession nos. MH553167 and MK300683. The efficacy of the isolates was tested on G. mellonella, using different nematodes' concentrations. Using 50 IJs/larvae from H. indica Aborawash and ERSAG2 showed 100 and 86% mortality rate after 48 h, respectively. The penetration rate reported in dead G. mellonella was 40% at H. indica Aborawash, while it was 35% in case of ERSAG2. [ABSTRACT FROM AUTHOR]

Fruit flies have a great influence on fruit and vegetable industry of Pakistan. Bactrocera dorsalis Hendel (Tephritidae) is a polyphagous pest in large number of fruit and vegetable crops worldwide. Virulence of 4 entomopathogenic nematodes (EPNs) species, Heterorhabditis bacteriophora, H. indica, Steinernema carpocapsae, and S. asiaticum, was evaluated at different temperature degrees (15, 20, 25, 30 and 35 °C) against the immature stages of fruit fly species, B. dorsalis. The tested EPNs species showed a temperature dependent virulence against the fruit fly immatures. All EPNs showed a poor infectivity at the lowest temperature (15 °C) and a high infectivity at the highest temperature (35 °C). In overall, H. bacteriophora performed the best against the fruit fly larvae and pupae at all temperature degrees. At 35 °C, all the EPNs caused more than 95% mortality in fruit fly maggots, but H. bacteriophora and S. carpocapsae performed better than the others. The EPNs infectivity increased with increasing the temperature and exposure time. Similar results were recorded in case of pupae. H. bacteriophora and S. carpocapsae caused more than 70% pupal mortality rates at 35 °C. [ABSTRACT FROM AUTHOR]

Entomopathogenic nematodes (EPNs) can provide a substantial control, especially of the root feeding larval pests. The objective of the present study was to examine beneficial traits of an indigenous entomopathogenic nematode species, Heterorhabditis bacteriophora Poinar (Hb-EG strain), and to identify superior biocontrol candidates for suppression of the scarab beetle Temnorhynchus baal (Reiche & Saulcy) (Coleoptera: Scarabaeidae: Dynastinae) larvae as serious pests of strawberry in Egypt. The nematodes were applied to infect the greater wax moth, Galleria mellonella L. cadavers, to represent natural emergence from the host in laboratory and under field conditions. Its average yield was 49604 infective juveniles (IJs) per G. mellonella larva. Overall averages of nematode-induced mortality in G. mellonella larvae were (4.63, 3.12, and 1.92) at 4, 8, and 12 weeks, respectively, after continuous weekly baiting with 5 cadavers. Nematode capability for infection and reproduction ranged from 72 to 26% one to five months, respectively, after field inoculation of the infected larvae into the strawberry rhizosphere. The number of IJs, moved to the North of the rhizosphere, was significantly (P ≤ 0.05) less than that moved to the South or the East as reflected by the numbers of infected insects. The factors that may have a marked influence on EPN foraging behavior, persistence, and movement direction with implications for harnessing them as biological pest control agents were discussed. [ABSTRACT FROM AUTHOR]

Experiments were conducted to test the pathogenicity of entomopathogenic nematode, Heterorhabditis pakistanensis alone and in combination with the chemical insecticides, viz., Dichlorvos and Quinalphos and Neem product, viz., Azadirachtin against the cabbage butterfly, Pieris brassicae (L.) (Lepidoptera: Pieridae) infesting cabbage plants under laboratory and field conditions. In laboratory test, inoculum level of 200 infective juveniles (IJs) was most effective causing mortality to both 3rd and 4th instars larvae at 48 h. Nematode multiplication rate in insect cadaver was inversely proportional to the size of initial inoculum level of IJs, whereas IJs yield was directly proportional to the size of larva. The 4th instar larva resulted in a highest yield of IJs, followed by 3rd, 2nd, and 1st instars larvae at all the inoculum levels used in the study. IJs were found compatible with the chemical insecticides and Neem product at lower than half of the optimum single dose. The cumulative mean survival percentage of IJs recorded the highest (77.5%) in the combination of 100 IJs + Azadirachtin (0.25%) and lowest (70.6%) in 100 IJs + Dichlorvos 76 EC (0.05%). Under field conditions, H. pakistanensis (3.0 lakh IJs/m2) + Dichlorvos 76 EC (0.025%) resulted to the highest larval mortality (79.65%), followed by H. pakistanensis (3.0 lakh IJs/m2) + Azadirachtin (0.25%), where it was 76.22%. The larval mortality was the least (61.16%) in case of H. pakistanensis (3.0 lakh IJs/m2) when applied alone. H. pakistanensis + Dichlorvos resulted to the highest increase (31.42%) in cabbage yield over untreated control. [ABSTRACT FROM AUTHOR]

Some hypotheses supported the concept that entomopathogenic nematodes are safe bio-agents, causing low infection probability to honey bee workers and brood under colonies conditions and have no effects on the colony strength and might be used as a bio-control agent against the greater wax moth Galleria mellonella. However, the obtained results showed that the mortality percentages in bee larvae after treatment with EPNs ranged from 49.2% to 77.6% in the case of Steinernema sp. isolates and from 39.8% to 55.2% in Heterorhabditis sp. isolates under the colony conditions, the nematode infection inside the entire colony was restricted to the treated areas and didn't widespread through the other frames. Direct treatments inside the laboratory also confirmed the susptibility of bee workers and larvae to nematode infection of all tested isolates with differences in successful recycling. The present work strongly supported that both Steinernematidae and Heterorhabditidae families are not recommended to be used in bee colonies as bio-control agents. Further research is needed to cover the possibilities of using them for infected wax combs during storage before reusing it in the bee colonies. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the efficacy of native entomopathogenic nematodes (EPNs); Steinernema affine 46 (Bovien, 1937), S. feltiae 879 (Filipjev, 1934), S. carpocapsae 1133 (Weiser, 1955) and Heterorhabditis bacteriophora 1144 (Poinar, 1976) on the larvae of tomato leafminer Tuta absoluta (Meyrick). Bioassays were conducted in the laboratory at four different temperatures (10, 15, 20 and 25±1 °C) in the plates and 30 infective juveniles (IJs) were inoculated to a single T. absoluta larva for each nematode species. After nematode inoculation, larvae were checked on the 3rd, 5th, 7th days and mortalities were recorded. All nematode species used in the study showed the lowest efficacy on the 3rd control day at 10 °C and the highest efficacy on the 7th day at 25 °C. S. feltiae 879 was found as the most efficient species with the highest mortality (91.67%) among EPNs used in the study. The results proved that T. absoluta larvae are highly susceptible to EPNs and the control of the pest by EPNs on this stage is successful.larva for each nematode species. After nematode inoculation, larvae were checked on the 3rd, 5th, 7th days and mortalities were recorded. All nematode species used in the study showed the lowest efficacy on the 3rd control day at 10 °C and the highest efficacy on the 7th day at 25 °C. S. feltiae 879 was found as the most efficient species with the highest mortality (91.67%) among EPNs used in the study. The results proved that T. absoluta larvae are highly susceptible to EPNs and the control of the pest by EPNs on this stage is successful. [ABSTRACT FROM AUTHOR]

Entomopathogenic nematodes (EPNs) in the families' Steinernematidae and Heterorhabditidae are obligate insect parasites. Their easy multiplication, broad host range, compatibility with chemical pesticides, and ease in application has grabbed interest among research practitioners to work on these beneficial microorganisms. Till date, around 100 valid species of Steinernema and 21 species of Heterorhabditis have been identified from different countries of the world. Extensive surveys have been conducted across the globe to isolate locally adapted EPN species and exploit them to suppress soil-dwelling and foliar insect pests in agricultural fields. Most of the new species have been described from Asia, whereas research in some Asian countries are still at infancy. Some new species have been recorded from Australia but very few surveys have been conducted in New Zealand. Likewise, less information about these tiny creatures is from Central America; however, in North America many new species have been described, some of which have been commercialized for insect pest control, whereas in South America, several native nematode species have been described and exploited as biological control agents. European countries have also been explored for EPN diversity and new species have been reported, exploited under field condition, and commercialized. Many new species and other previously described species have been reported from Africa. Despite frequent surveys in different continents of the world, number of sites touched are low and, therefore, further surveys are still needed to explore untouched geographic areas and climatic conditions, both in plantations and indigenous forests with an aim to identify and exploit additional EPN species. [ABSTRACT FROM AUTHOR]

In a recent survey, we have isolated six entomopathogenic nematodes from Hapur, Shamli, Saharanpur and Meerut districts of western Uttar Pradesh. Preliminary identification at genus level classified one isolate as Heterorhabditis sp., two isolates as Steinernema spp. and three as Oscheius spp. These six newly isolated EPNs have been designated as Oscheius sp. (IARI-EPN RP 01), Oscheius sp. (IARI-EPN RP 02), Steinernema sp. (IARI-EPN RP 03), Oscheius sp. (IARI-EPN RP 04), Steinernema sp. (IARI-EPN RP 05) and Heterorhabditis sp. (IARI-EPN RP 06). All these were evaluated for infectivity against lepidopteran larvae, Maruca vitrata infesting pigeonpea, Pieris brassicae infesting mustard and Spodoptera litura infesting chickpea. Among the tested EPNs, Steinernema sp. (IARI-EPN RP 03), Oscheius sp. (IARIEPN RP 04), Heterorhabditis sp. (IARI-EPN RP 06) were found to be promising against M. vitrata as they showed 100% mortality within 48 h followed by Oscheius sp. (IARI-EPN RP 01), Oscheius sp. (IARI-EPN RP 02) which took 72 h, while Steinernema sp. (IARI-EPN RP 05) took about 120 h to kill the insects. Oscheius sp. (IARI-EPN RP 02), Steinernema sp. (IARI-EPN RP 03) and Heterorhabditis sp. (IARI-EPN RP 06) gave 100% mortality of P. braissicae within 48 h followed by Oscheius sp. (IARI-EPN 04) and Steinernema sp. (IARI-EPN RP 05) that killed larvae after 72 h, while Oscheius sp. (IARI-EPN RP 01) took about 120 h. Lastly, Steinernema sp. (IARI-EPN RP 03) and Heterorhabditis sp. (IARI-EPN 06) were found promising for S. litura as both of them caused 100% mortality within 48 h followed by Oscheius sp. (IARI-EPN RP 01), Oscheius sp. (IARI-EPN RP 02) and Steinernema sp. (IARI-EPN RP 05) that took 72 h, while, Oscheius sp. (IARI-EPN RP 04) was effective at about 120 h. The present results indicated that both Steinernema sp. (IARI-EPN RP 03) and Heterorhabditis sp. (IARI-EPN RP 06) were highly virulent against the tested lepidopteran insect pests. Further evaluation of these new EPN isolates under field conditions will indicate their utility in integrated pest management. [ABSTRACT FROM AUTHOR]

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)