Genome-wide analyses provide insights into genetic variation, phylo- and co-phylogenetic relationships, and biogeography of the entomopathogenic nematode genus Heterorhabditis.

Multigene, genus-wide phylogenetic studies have uncovered the limited taxonomic resolution power of commonly used gene markers, particularly of rRNA genes, to discriminate closely related species of the nematode genus Heterorhabditis. In addition, conflicting tree topologies are often obtained using the different gene markers, which limits our understanding of the phylo- and co-phylogenetic relationships and biogeography of the entomopathogenic nematode genus Heterorhabditis. Here we carried out phylogenomic reconstructions using whole nuclear and mitochondrial genomes, and whole ribosomal operon sequences, as well as multiple phylogenetic reconstructions using various single nuclear and mitochondrial genes.

Xenorhabdus bharatensis sp. nov., Xenorhabdus entomophaga sp. nov., Xenorhabdus siamensis sp. nov., and Xenorhabdus thailandensis sp. nov. Isolated from Steinernema Entomopathogenic Nematodes.

Four Gram-stain-negative bacterial strains, CS20, AUT15.5, XENO-11, and CCN3.3, isolated from Steinernema entomopathogenic nematodes, were found to represent novel species within the genus Xenorhabdus (Gammaproteobacteria, Morganellaceae).

Photorhabdus viridis sp. nov. Isolated from Heterorhabditis zealandica Entomopathogenic Nematodes.

A novel bacterial species, Photorhabdus viridis sp. nov., represented by strain Green, isolated from Heterorhabditis zealandica MJ2C entomopathogenic nematodes, is described.

Bacterial bioluminescence is an important regulator of multitrophic interactions in the soil.

Enormous efforts have been made to understand the functions of bioluminescence; however, its relevance in soil ecosystems has barely been investigated. In addition, our understanding of the biological relevance of bioluminescence is hampered by the scarcity of tools to genetically manipulate this trait. Using the symbionts of entomopathogenic nematodes, Photorhabdus bacteria, we show that bioluminescence plays important regulatory roles in multitrophic interactions in the soil.

Harnessing Walnut-Based Zinc Oxide Nanoparticles: A Sustainable Approach to Combat the Disease Complex of and in Cowpea.

Zinc oxide nanoparticles (ZnO NPs) exhibit diverse applications, including antimicrobial, UV-blocking, and catalytic properties, due to their unique structure and properties. This study focused on the characterization of zinc oxide nanoparticles (ZnO NPs) synthesized from Juglans regia leaves and their application in mitigating the impact of simultaneous infection by (root-knot nematode) and (root-rot fungus) in cowpea plants. The characterization of ZnO NPs was carried out through various analytical techniques, including UV-visible spectrophotometry, Powder-XRD analysis, FT-IR spectroscopy, and SEM-EDX analysis.

Photorhabdus africana sp. nov. isolated from Heterorhabditis entomopathogenic nematodes.

One Gram-negative, rod-shaped bacterial strain, isolated from an undescribed Heterorhabditis entomopathogenic nematode species was characterized to determine its taxonomic position. The 16S rRNA gene sequences indicate that it belongs to the class Gammaproteobacteria, to the family Morganellaceae, to the genus Photorhabdus, and likely represents a novel bacterial species. This strain, designated here as CRI-LC, was therefore molecularly, biochemically, and morphologically characterized to describe the novel bacterial species.

Exploiting fly ash as an ecofriendly pesticide/nematicide on Abesmoschus esculuntus: Insights into soil amendment-induced antioxidant fight against nematode mediated ROS.

Conventional pest control measures, such as chemical pesticides and nematicides, have limited efficacy and raise environmental concerns, necessitating sustainable and eco-friendly alternatives for pest management. Therefore, to find a complementary eco-friendly pesticide/nematicide, this study investigated the role of fly ash (FA) in managing a notorious pest, Meloidogyne javanica and its impact on the growth and physiology of Abelmoschus esculentus. Molecular characterization using SSU and LSU rDNA gene markers confirmed the identity of Indian M.

Morphological and molecular profiling of an entomopathogenic nematode Steinernema feltiae: Unlocking its biocontrol potential against vegetable insect pests.

A population of entomopathogenic nematodes, belonging to the Feltiae-clade and labelled J13, was discovered in the agricultural soils of the hilly regions of the Union territory of Jammu and Kashmir, India. Based on morphological, morphometric, and molecular analyses, the nematodes were identified as Steinernema feltiae. The J13 nematode isolate was tested in a laboratory assay for its pathogenicity against six major pests of vegetable crops: Pieris brassicae, Plutella xylostella, Helicoverpa armigera, Agrotis iplison, Trichoplusia ni, and Exelastis atomosa.

Uncovering the antimicrobial activity of G-type lysozyme 2 derived from Cyprinus carpio mucus against bacterial and fungal pathogens.

This study aimed to explore the antimicrobic potential of mucus samples collected from Cyprinus carpio and identify the specific antimicrobial peptides responsible for its activity. The crude extract was tested against various bacterial and fungal pathogens, and its protein content and profile were analyzed. Purification steps, including gel filtration chromatography, were employed to isolate the most active fraction (peak IV), which was further identified via liquid chromatography and mass spectroscopy.

Taxonomic and molecular characterization of a new entomopathogenic nematode species, Heterorhabditis casmirica n. sp., and whole genome sequencing of its associated bacterial symbiont.

Background: Nematodes of the genus Heterorhabditis are important biocontrol agents as they form a lethal combination with their symbiotic Photorhabdus bacteria against agricultural insect pests. This study describes a new species of Heterorhabditis.

Methods: Six Heterorhabditis nematode populations were recovered from agricultural soils in Jammu and Kashmir, India.

Corrigendum: From soil to plant: strengthening carrot defenses against with vermicompost and arbuscular mycorrhizal fungi biofertilizers.

[This corrects the article DOI: 10.3389/fmicb.2023.

The hidden world of fish fungal pathogens: molecular identification and phylogenetic analysis in common carp, Cyprinus carpio.

Fungal infections pose a significant threat to aquaculture, causing substantial economic losses and ecological disruptions. The common carp (Cyprinus carpio), as a crucial farmed fish, requires in-depth research to uncover the underlying fungal pathogens affecting its health. In this study, we analyzed 150 samples of C.

Xenorhabdus aichiensis sp. nov., Xenorhabdus anantnagensis sp. nov., and Xenorhabdus yunnanensis sp. nov., Isolated from Steinernema Entomopathogenic Nematodes.

Three bacterial strains, XENO-2, XENO-7, and XENO-10, isolated from Steinernema entomopathogenic nematodes, were found to represent novel Xenorhabdus species. In this study, we describe these new species by whole-genome and whole-proteome phylogenomic reconstructions, by calculating sequence identity scores using core genome sequences, and by phenotypic characterization. Phylogenomic reconstructions using ribosomal and house-keeping genes, and whole-genome and whole-proteome sequences show that XENO-2 and XENO-10 are closely related to Xenorhabdus japonica DSM 16522 and that XENO-7 is closely related to Xenorhabdus bovienii subsp.

Multigene Sequence-Based and Phenotypic Characterization Reveals the Occurrence of a Novel Entomopathogenic Nematode Species, n. sp.

Three entomopathogenic nematode populations were isolated from agricultural fields in the Anantnag district of Jammu and Kashmir (India). Sequences of multiple gene regions and phenotypic features show that they are conspecific and represent a novel species. Molecular and morphological features provided evidence for placing the new species into the "" clade.

sp. nov. and subsp. subsp. nov., isolated from entomopathogenic nematodes.

Six Gram-negative, rod-shaped bacterial strains isolated from entomopathogenic nematodes were characterized to determine their taxonomic position. 16S rRNA and gene sequences indicate that they belong to the class , family and genus , and that some of them are conspecifics. Two of them, APURE and JAR, were selected for further molecular characterization using whole genome- and whole-proteome-based phylogenetic reconstructions and sequence comparisons.

subsp. subsp. nov., isolated from entomopathogenic nematodes.

Four Gram-negative bacterial strains isolated from entomopathogenic nematodes were biochemically and molecularly characterized to determine their taxonomic position. Results of 16S rRNA gene sequencing indicated that they belong to the class , family , genus , and that they are conspecific. The average 16S rRNA gene sequence similarity between the newly isolated strains and the type strain of its more closely related species, T228, is 99.

Entomopathogenic potential of bacteria associated with soil-borne nematodes and insect immune responses to their infection.

Soil-borne nematodes establish close associations with several bacterial species. Whether they confer benefits to their hosts has been investigated in only a few nematode-bacteria systems. Their ecological function, therefore, remains poorly understood.

n. Sp. (Rhabditida, Steinernematidae), a New Entomopathogenic Nematode Species Isolated in the Republic of Rwanda.

Alternatives to hazardous insecticides are urgently needed for an environmentally friendly and effective management of insect pests. One such option is the use of entomopathogenic nematodes (EPN). To increase the availability of EPN with potential for biocontrol, we surveyed agricultural soils in the Republic of Rwanda and collected two isolates.

Potential of Oscheius tipulae nematodes as biological control agents against Ceratitis capitata.

A survey to collect soil nematodes with potential to control Ceratitis capitata flies was carried out in different locations in Tunisia. Several nematode isolates were recovered, laboratory colonies were established, and their taxonomic identities were determined based on molecular methods. Among all the recovered nematode isolates, two of them, Oscheius tipulae TC2 and OC2, were evaluated for their capacity to control C.

Morphological, Morphometrical and Molecular Characterization of Tabassum and Shahina, 2010 (Rhabditida, Rhabditidae) from India with Its Taxonomic Consequences for the Subgenus Andrássy, 1976.

An insect parasitic nematode belonging to the genus was recovered from the agricultural soils from the Hapur district in western Uttar Pradesh, India. Morphological studies on this species exhibited its high resemblance with two Pakistani species:   and . No molecular data are available for these taxa but, morphologically, both species do not differ significantly from our strains and each other.