Abstract Background Entomopathogenic nematodes (EPNs), as biological control agents, have been isolated from many regions throughout the world. Local isolates of EPNs are usually more effective for controlling indigenous insect pests they adapted to local environmental conditions and pest species. Results In present work, EPN were searched in soil under citrus guava trees, Egyptian clover at No...

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 experimenta...

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 (H...

Injection, contact, and soil assays were used to compare infectivity of Heterorhabditis bacteriophora strain HP88 and Steinernema carpocapsae strain All to final instar Galleria mellonella larvae. Under comparable assay conditions, H. bacteriophora produced less Galleria mortality and showed greater within-assay variability in infectivity than S. carpocapsae. Injection of individual S. carpocap...

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 cla...

Rifampin resistant (Rif(R)) mutants of the insect pathogenic bacterium Photorhabdus luminescens LN2 from entomopathogenic nematode Heterorhabditis indica LN2 were genetically and proteomically characterized. The Rif(R) mutants showed typical phase one characters of Photorhabdus bacteria, and insecticidal activity against Galleria mellonella larvae, but surprisingly influenced their nematicidal ...

Steinernema riobrave ranks as the most efficacious entomopathogenic nematode for inundative biological control (biopesticide) applications against larvae of the root weevil Diaprepes abbreviatus in Florida citrus groves and has been commercially available for several years. However, only one strain is known, and others could be more effective. Therefore, we used two soil sampling techniques (co...

Entomopathogenic nematodes of the family Steinernematidae and their mutualistic bacteria (Xenorhabdus spp.) are lethal endoparasites of insects. We hypothesized that growth of the nematode's mutualistic bacteria in the insect host may contribute to the production of cues used by the infective juveniles (IJs) in responding to potential hosts for infection. Specifically, we tested if patterns of ...

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 ...

We describe the isolation and characterization of an insect pathogenic bacterium from the entomopathogenic nematode Heterorhabditis indica (Karnataka strain), an isolate from the southern regions of India. The strain has been identified and characterized by phenotypic, biochemical tests and PCR-RFLP analysis of the 16S rRNA gene as Photorhabdus luminescens subsp. akhurstii. The insecticidal tox...