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Pest Management Science Jun 2024The citrus red mite, Panonychus citri is a serious pest of the citrus industry and has developed resistance to many acaricides. Broflanilide is a novel meta-diamide...
BACKGROUND
The citrus red mite, Panonychus citri is a serious pest of the citrus industry and has developed resistance to many acaricides. Broflanilide is a novel meta-diamide insecticide that binds to a new site on the γ -aminobutyric acid receptor with high potency against pests. However, little information has been reported about its effect on the citrus red mite.
RESULTS
Broflanilide exhibited higher toxicity to female adults and eggs of a laboratory strain of P. citri The median lethal concentration (LC), 9.769 mg/L and 4.576 mg/L, respectively) than other commonly used acaricides and was also toxic to two P. citri field strains. Broflanilide treatment with LC, LC, and LC significantly decreased the fecundity and longevity of female adults of F P. citri compared with the control. The duration of larva, protonymph, deutonymph and adult, and total life span in the F generation were significantly reduced after treatment of F with broflanilide. Population parameters, including the intrinsic rate of increase (r) and finite rate of increase (λ), were significantly increased, and the mean generation time (T) of F progeny was significantly reduced in the LC treatment. The predicted population size of F increased when parental female adults were treated with sublethal concentrations.
CONCLUSION
Broflanilide had high acaricidal activity toward P. citri, and exposure to a sublethal concentration significantly inhibited the population growth of F. The transgenerational hormesis effect is likely to cause population expansion of F. More attention should be paid when broflanilide is applied to control P. citri in citrus orchards. © 2024 Society of Chemical Industry.
PubMed: 38924229
DOI: 10.1002/ps.8270 -
Immunology and Cell Biology Jun 2024Eosinophils play divergent roles in health and disease, contributing to both immunoregulatory and proinflammatory responses. Helminth infection is strongly associated...
Eosinophils play divergent roles in health and disease, contributing to both immunoregulatory and proinflammatory responses. Helminth infection is strongly associated with eosinophilia and the induction of the type 2 cytokines interleukin (IL)-5, IL-4 and IL-13. This study aimed to elucidate the heterogeneity of pulmonary eosinophils in response to helminth infection and the roles of IL-5, IL-4 and IL-13 in driving pulmonary eosinophil responses. Using the murine helminth model Nippostrongylus brasiliensis (Nb), we characterize a subtype of eosinophils, defined by high expression of CD101, that is induced in the lungs of Nb-infected mice and are phenotypically distinct from lung eosinophils that express low levels of CD101. Strikingly, we show that the two eosinophil subtypes have distinct anatomical localization within the lung: CD101 eosinophils are predominantly localized in the lung vasculature, whereas Nb-induced CD101 eosinophils are predominantly localized in the extravascular lung niche. We show that CD101 eosinophils are also induced across other models of pulmonary infection and inflammation, including a nonlung-migrating helminth infection, house dust mite-induced allergic inflammation and influenza infection. Furthermore, we demonstrate that the induction of CD101 tissue eosinophils is independent of IL-5 and IL-4 signaling, but is dependent on intact IL-13 signaling. These results suggest that IL-13 produced during helminth infection and other disease states promotes a pulmonary tissue-infiltrating program in eosinophils defined by high expression of CD101.
PubMed: 38924182
DOI: 10.1111/imcb.12796 -
Proceedings of the National Academy of... Jul 2024Asthma is a widespread airway disorder where GATA3-dependent Type-2 helper T (Th2) cells and group 2 innate lymphoid cells (ILC2s) play vital roles. Asthma-associated...
Asthma is a widespread airway disorder where GATA3-dependent Type-2 helper T (Th2) cells and group 2 innate lymphoid cells (ILC2s) play vital roles. Asthma-associated single nucleotide polymorphisms (SNPs) are enriched in a region located 926-970 kb downstream from GATA3 in the 10p14 (hG900). However, it is unknown how hG900 affects the pathogenesis of allergic airway inflammation. To investigate the roles of the asthma-associated GATA3 enhancer region in experimental allergic airway inflammation, we first examined the correlation between GATA3 expression and the activation of the hG900 region was analyzed by flow cytometry and ChIP-qPCR. We found that The activation of enhancers in the hG900 region was strongly correlated to the levels of GATA3 in human peripheral T cell subsets. We next generated mice lacking the mG900 region (mG900KO mice) were generated by the CRISPR-Cas9 system, and the development and function of helper T cells and ILCs in mG900KO mice were analyzed in steady-state conditions and allergic airway inflammation induced by papain or house dust mite (HDM). The deletion of the mG900 did not affect the development of lymphocytes in steady-state conditions or allergic airway inflammation induced by papain. However, mG900KO mice exhibited reduced allergic inflammation and Th2 differentiation in the HDM-induced allergic airway inflammation. The analysis of the chromatin conformation around by circular chromosome conformation capture coupled to high-throughput sequencing (4C-seq) revealed that the mG900 region interacted with the transcription start site of with an influencing chromatin conformation in Th2 cells. These findings indicate that the mG900 region plays a pivotal role in Th2 differentiation and thus enhances allergic airway inflammation.
Topics: GATA3 Transcription Factor; Animals; Th2 Cells; Mice; Cell Differentiation; Asthma; Enhancer Elements, Genetic; Humans; Mice, Knockout; Inflammation; Hypersensitivity; Polymorphism, Single Nucleotide; Mice, Inbred C57BL
PubMed: 38923989
DOI: 10.1073/pnas.2320727121 -
International Journal of Dermatology Jun 2024Scabies, caused by the Sarcoptes scabiei var hominis mite burrowing into the skin, is a highly contagious disease characterized by intense nocturnal itching. Its global... (Review)
Review
Scabies, caused by the Sarcoptes scabiei var hominis mite burrowing into the skin, is a highly contagious disease characterized by intense nocturnal itching. Its global impact is considerable, affecting more than 200 million individuals annually and posing significant challenges to healthcare systems worldwide. Transmission occurs primarily through direct skin-to-skin contact, contributing to its widespread prevalence and emergence as a substantial public health concern affecting large populations. This review presents consensus-based clinical practice guidelines for diagnosing and managing scabies, developed through the fuzzy Delphi method by dermatology, parasitology, pediatrics, pharmacology, and public health experts. The presence of burrows containing adult female mites, their eggs, and excreta is the diagnostic hallmark of scabies. Definitive diagnosis typically involves direct microscopic examination of skin scrapings obtained from these burrows, although dermoscopy has become a diagnostic tool in clinical practice. Treatment modalities encompass topical agents, such as permethrin, balsam of Peru, precipitated sulfur, and benzyl benzoate. In cases where topical therapy proves inadequate or in instances of crusted scabies, oral ivermectin is recommended as a systemic treatment option. This comprehensive approach addresses the diagnostic and therapeutic challenges associated with scabies, optimizing patient care, and management outcomes.
PubMed: 38922701
DOI: 10.1111/ijd.17327 -
Experimental & Applied Acarology Jun 2024
PubMed: 38922519
DOI: 10.1007/s10493-024-00940-5 -
Experimental & Applied Acarology Jun 2024Viticulture is characterized by substantial pesticide applications, impacting natural enemies. New pest control strategies and management of plant diversity into...
Viticulture is characterized by substantial pesticide applications, impacting natural enemies. New pest control strategies and management of plant diversity into agrosystems acting as reservoirs of natural enemies are assumed to limit pesticide use. Various studies support this hypothesis but gaps exist on the effect of diversification on Phytoseiidae mites, generalist predators reported as prevalent and efficient natural enemies in vineyards. This study focuses on the effect of cover crop management (no cover crop, spontaneous cover crops with or without agroforestry) and grape variety (resistant cv. Artaban and cv. Syrah) on predatory mites and prey communities, in a newly planted experimental vineyard in South-East France. Samplings were carried out three times a year on vine, cover crops, and co-planted trees. Phytoseiidae, Tydeiidae, Eriophyidae mites and thrips were characterized. Nine Phytoseiidae species were identified on vine, the main ones being Kampimodromus aberrans, Typhlodromus exhilaratus, Phytoseius finitimus and Euseius gallicus. Kampimodromus aberrans was prevalent on the cv. Syrah, highlighting a strong effect of variety. The low unexpected effect of system management observed outcome could be due to several factors, such as the experimental plot size or the influence of vine stress on Phytoseiidae communities in vines with cover crops. All phytoseiid species present on vine were identifed at least once on cover crops and co-planted trees, suggesting their potential role as reservoirs. Further studies should be performed investigating the evolution of communities in this newly-planted experimental system, as well as potential differences in trophic network interactions.
PubMed: 38922518
DOI: 10.1007/s10493-024-00938-z -
Parasitology Research Jun 2024Hyperparasitism is defined as the interaction where one parasite is infected by another parasite. In bat flies (Streblidae and Nycteribiidae), both hyperparasites and...
Hyperparasitism is defined as the interaction where one parasite is infected by another parasite. In bat flies (Streblidae and Nycteribiidae), both hyperparasites and microparasites (bacteria, viruses, fungi, and arthropods such as mites) have been documented. Fungi belonging to the order Laboulbeniales are microscopic parasites of a wide diversity of arthropod hosts. Three genera exclusively target bat flies: Arthrorhynchus, which parasitizes species within Nycteribiidae in the Eastern Hemisphere, while genus Gloeandromyces and Nycteromyces parasitize Streblidae in the Western Hemisphere. Among the hyperparasitic arthropods, mites of family Neothrombidiidae, particularly the monospecific genus Monunguis, are known to parasitize bat flies. Here we present the first records of the hyperparasites Monunguis streblida and Gloeandromyces pageanus f. polymorphus parasitizing Streblidae bat flies in Colombia and a summary of these hyperparasitic interactions in the Neotropics. We detected fungi and mites parasitizing bat flies that were collected in the Magdalena River Basin, Colombia, in field expeditions in 2018, 2022, and 2023. We identified 17 bat flies and two species of hyperparasites, specifically M. streblida and the fungi Gloeandromyces. Our search for reports of these interactions in the Neotropics revealed that seven species of Trichobius (Streblidae) are parasitized by M. streblida, whereas Paratrichobius longicrus (Streblidae) is parasitized by Gloeandromyces pageanus f. polymorphus. These interactions have been reported in 11 countries, but our records are the first of M. streblida and Laboulbeniales fungi parasitizing bat flies in Colombia. So far, a total of 14 species of fungi and one species of mite have been associated with 19 species of bat flies, which in turn, are linked to 15 species of Neotropical bats.
Topics: Animals; Diptera; Chiroptera; Colombia; Mites; Host-Parasite Interactions
PubMed: 38922514
DOI: 10.1007/s00436-024-08221-1 -
Insects Jun 2024are predaceous mites that feed on phytophagous mites, pollens, and plant exudates and are known as one of the most potent biological pest management agents. is a...
are predaceous mites that feed on phytophagous mites, pollens, and plant exudates and are known as one of the most potent biological pest management agents. is a global mite that is difficult to manage because of its high population growth rates, necessitating alternative management measures like biological control. Regarding the functional response, the effects of temperature and prey density are some of the essential behaviors of natural enemies. This study investigates the effect of varying temperatures and prey densities on , a biological control agent for . The present results demonstrated the change in the functional response estimates when was reared at various temperatures and different prey densities. The results of the estimates regarding the searching efficiency () showed the highest value ( = 0.919) at 26 °C and the lowest value ( = 0.751) at 14 °C. The handling time per prey item () for the predatory mites changed with the temperature and prey density, showing the shortest handling time at 26 °C ( = 0.005) and the highest value at 14 °C ( = 0.015). The functional response curves matched the type II functional response model, demonstrating the inverse dependence of temperatures and prey density with a positive quadratic coefficient. The predation curves for showed a significant difference between the mean numbers of consumed at various prey densities and temperatures, illustrating a relationship between and Therefore, the results of this research may be utilized to forecast the behavior of and its usefulness in controlling populations.
PubMed: 38921159
DOI: 10.3390/insects15060444 -
Insects Jun 2024Implementation of marker-assisted selection (MAS) in modern beekeeping would improve sustainability, especially in breeding programs aiming for resilience against the...
Implementation of marker-assisted selection (MAS) in modern beekeeping would improve sustainability, especially in breeding programs aiming for resilience against the parasitic mite . Selecting honey bee colonies for natural resistance traits, such as brood-intrinsic suppression of varroa mite reproduction, reduces the use of chemical acaricides while respecting local adaptation. In 2019, eight genomic variants associated with varroa non-reproduction in drone brood were discovered in a single colony from the Amsterdam Water Dune population in the Netherlands. Recently, a new study tested the applicability of these eight genetic variants for the same phenotype on a population-wide scale in Flanders, Belgium. As the properties of some variants varied between the two studies, one hypothesized that the difference in genetic ancestry of the sampled colonies may underly these contribution shifts. In order to frame this, we determined the allele frequencies of the eight genetic variants in more than 360 colonies across the European continent and found that variant type allele frequencies of these variants are primarily related to the subspecies or phylogenetic honey bee lineage. Our results confirm that population-specific genetic markers should always be evaluated in a new population prior to using them in MAS programs.
PubMed: 38921134
DOI: 10.3390/insects15060419 -
Insects May 2024Thrips biocontrol research in greenhouse crops has focused primarily on western flower thrips (WFT; ). However, recent outbreaks of onion thrips (OT; ) in Ontario,...
Thrips biocontrol research in greenhouse crops has focused primarily on western flower thrips (WFT; ). However, recent outbreaks of onion thrips (OT; ) in Ontario, Canada, demonstrate that biocontrol-based IPM programs for WFT do not control OT sufficiently to prevent crop losses. A lack of comparative studies makes it difficult to determine which program components for WFT are failing for OT. We conducted several laboratory trials examining the extent to which commercial biocontrol products kill OT compared to WFT. These included phytoseiid mites (, , , ), a large generalist predator (), an entomopathogenic fungus strain GHA), and entomopathogenic nematodes (, , ). In no-choice trials, and consumed more OT than WFT (first instars and adults, respectively). In choice trials, , , and consumed more OT than WFT. caused higher mortality in OT than WFT. There was no difference in mortality between thrips species exposed to other biocontrol agents. This suggests available tools have the potential to manage OT as well as WFT. Possible explanations why this potential is not realized in commercial settings are explored.
PubMed: 38921115
DOI: 10.3390/insects15060400