Journal of invertebrate pathology最新文献

{"title":"Distribution and genetic diversity of Bombyx mori nucleopolyhedrovirus in mass-reared silkworms in Thailand","authors":"","doi":"10.1016/j.jip.2024.108221","DOIUrl":"10.1016/j.jip.2024.108221","url":null,"abstract":"<div><div>Silk is an economically and culturally important product of Thailand that is threatened by the outbreaks of the Bombyx mori nucleopolyhedrovirus (BmNPV) in silkworm rearings. BmNPV infects the larval stages of the silkworm <em>Bombyx mori</em>, causing fatal viral infection and preventing the larvae from reaching the pupal stage. Numerous BmNPV isolates have been described from silk-producing countries from all over the world. In this study, the geographic distribution of BmNPV in Thailand was analyzed by collecting 18 samples from different regions. The BmNPV samples were analyzed by PCR and whole genome sequencing was performed for eight specimens. Their genome size ranged from 125,888 bp to 126,783 bp, comprising 138 open reading frames. Although the sequenced BmNPV genomes could be phylogenetically differentiated, no correlation between geographic and genetic distance was observed, indicating a close relationship between the BmNPV from Thailand.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142467750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics of vhvp-2 gene distribution and diversity within the Vibrio causing translucent post-larvae disease (TPD)","authors":"","doi":"10.1016/j.jip.2024.108228","DOIUrl":"10.1016/j.jip.2024.108228","url":null,"abstract":"<div><div>Translucent post-larva vibriosis (<em>V</em>_TPD) in <em>Penaeus vannamei</em>, caused by the virulence factor <em>Vibrio</em> high virulent protein 2 (<em>vhvp-2</em>) gene, poses a significant threat to the shrimp aquaculture industry in China. This study conducted a comprehensive analysis of the <em>vhvp-2</em> gene distribution and genetic diversity among <em>Vibrio</em>, which play a key role in the pathogenesis of translucent post-larvae disease (TPD). A total of 6281 <em>Vibrio</em> genomes from the NCBI database were screened, revealing the presence of the <em>vhvp-2</em> gene in 26 strains, predominantly in <em>V. parahaemolyticus</em>, with diverse locations on both plasmids and chromosomes. Comparative analysis of the genomes, plasmids, and the <em>vhvp-2</em> gene successfully differentiated three distinct clusters of <em>Vibrio</em> species and identified at least two major plasmid groups. However, these plasmid groups did not exhibit the same evolutionary relationships as the host bacteria themselves. The analysis also revealed the conserved presence of the <em>vhvp-2</em> gene along with genetic variations. Moreover, the widespread presence of antimicrobial resistance genes (ARGs) and virulence factors in <em>Vibrio</em> strains enhances their pathogenicity and poses increased public health risks. The findings underscore the importance of understanding the adaptability, evolution, and ecological characteristics of <em>Vibrio</em> strains harboring <em>vhvp-2</em> gene. This research provides a scientific foundation for the development of effective disease prevention and control strategies, contributing to the mitigation of TPD’s impact on the shrimp aquaculture industry and supporting its sustainable and healthy growth.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142568930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The combined effect of herbicide and Bacillus thuringiensis exposure delays development in the red flour beetle","authors":"","doi":"10.1016/j.jip.2024.108227","DOIUrl":"10.1016/j.jip.2024.108227","url":null,"abstract":"<div><div>The use of herbicides and their long persistence in the environment have raised concerns about potential harm to ecosystems and human health. However, there is a gap in the knowledge regarding the effects of continuous exposure to residues or admitted field doses on non-target organisms such as insects that inhabit croplands and play key ecological roles. Furthermore, the potential impact of this exposure on host-pathogen interactions remains largely unstudied. This study adopted an eco-immunological perspective, investigating the influence of herbicides on an organism’s interaction with natural pathogens. The impact of this combination of multiple stressors was studied in larvae of the red flour beetle, <em>Tribolium castaneum</em> Herbst, 1797, previously treated with a pendimethalin-based commercial formulation (PND) and exposed to the natural entomopathogen <em>Bacillus thuringiensis</em> (1x10⁹, 1x10¹⁰ cells/mL)<em>.</em> The effects of three PND concentrations (i.e. a recommended field rate, a soil contaminant concentration and the maximum residue limit admitted in grain in EU countries: 4L/ha, 13 and 0.05 ppm, respectively) on life history traits such as developmental time, pupation rate and survival rate and the expression levels of antimicrobial peptides (AMPs) were assessed. The results showed that even at doses considered safe for human consumption or field application, exposure to PND had an impact on beetle larvae, affecting their vulnerability to <em>B. thuringiensis</em>. The combined experience of exposure to PND and <em>B. thuringiensis</em> at the larval stage resulted in a delay of larval development, a reduction in the number of pupae and emerging adults, and alterations in their body condition. Moreover, changes in the expression levels of the analysed AMPs, including Attacin 1, Defensin 2 and Coleoptericin 2, were recorded as markers for immune activity against the bacterium. The findings of this study highlight the general need for further studies on the effects of commonly used herbicides on the physiology of non-target organisms and on host-pathogen interactions at the community level. Additionally, there is a need for the establishment of revised residual levels that are deemed non-toxic to soil organisms and humans.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142545942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metacollinia emscheri n. sp., a novel sanguicolous apostome ciliate of freshwater amphipods (Gammarus spp.)","authors":"","doi":"10.1016/j.jip.2024.108224","DOIUrl":"10.1016/j.jip.2024.108224","url":null,"abstract":"<div><div>We describe a novel sanguicolous parasitic ciliate, <em>Metacollinia emscheri</em> n. sp., found in the freshwater amphipods <em>Gammarus pulex</em> and <em>G. fossarum</em>. This ciliate infected 8.05 % of the amphipods collected in a German stream catchment, the Boye, a tributary of the river Emscher. The ciliate showed morphological characteristics fitting the genus <em>Metacollinia</em>. Different life stages of variable size occurred simultaneously in the hemocoel throughout the hosts’ body. The tomont had 40–47 slightly spiraled kineties, a non-ciliated cortical band, a large macronucleus, and contractile vacuoles arranged in rows or scattered throughout the cytoplasm. The protomites/tomites with nine somatic kineties presented evidence of the buccal kineties x, y, and z reminiscent of those of the order Foettingeriida. Phylogenetic analyses of the 18S rRNA and COI regions confirm the ciliate placement in the Collinidae and a close relatedness to the type species of the genus <em>Metacollinia</em>, <em>Metacollinia luciensis</em>.</div><div>We formally describe this new parasite as <em>Metacollinia emscheri</em> n. sp. using pathological, morphological, and nuclear/mitochondrial genetic data. The systemic infections observed in histological preparations and the pathogenicity of <em>Metacollinia emscheri</em> n. sp. suggest that this parasite might influence host population dynamics. Given the ecological importance of amphipods as keystone species in freshwater ecosystems, an outbreak of this parasite might indirectly impact ecosystem functioning.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142502200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isolation and identification of native Chilean entomopathogenic fungi and their potential for the control of Drosophila suzukii.","authors":"Cristian Montalva, Cristian González, Cecilia Ruiz, Isabel Vives, Andrea Díaz, Luis Devotto, Juscelino Rodrigues, Luiz F N Rocha, Javiera Manríquez, Tania Vásquez, Richard A Humber, Christian Luz","doi":"10.1016/j.jip.2024.108223","DOIUrl":"10.1016/j.jip.2024.108223","url":null,"abstract":"<p><p>Drosophila suzukii is an invasive pest of berries and other soft-skinned fruits, was first detected in Chile in 2017, and has since spread over 2,800 km from north to south. Sustainable control of the spotted-wing drosophila (SWD) is essential due the negative attitude of the consumers toward the excessive use of insecticides. During a survey in Chile for biological control agents, thirty-two isolates of entomopathogenic fungi (EPF) were isolated from mycotized insects and soil samples, identified through sequence analysis, and tested against D. suzukii adults under laboratory conditions. The EPF identified are Akanthomyces muscarius, Beauveria bassiana, Beauveria pseudobassiana, Clonostachys rosea, Metarhizium alvesii, Metarhizium brunneum and Metarhizium robertsii. Six isolates caused 100 % of mortality of D. suzukii adults within ten days after the initial exposition to conidia; these included four B. bassiana isolates (LSB 110, LSB 114, LSB 122 and LSB 125), one M. robertsii isolate (LSB 115) and one M. brunneum isolate (LSB 127). LSB 122 and LSB 125 induced the shortest lethal time (LT₅₀ 4 and 4.2 days, respectively), while Akanthomyces and Clonostachys caused ≤ 36 % cumulative mortality of the adults at 10 days of exposure. These results indicate that isolates of B. bassiana, M. robertsii and M. brunneum have significant potential as microbial control agents against D. suzukii adults. This study marks a critical step forward in identifying and validating native entomopathogenic fungi in Chile for sustainable pest management. Future work will focus on further testing these isolates under laboratory, semi-field and field conditions to optimize their application in real-world agricultural settings.</p>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142502199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ferroptotic cyanobacteria as biocontrol agent of the southern house mosquito Culex quinquefasciatus","authors":"","doi":"10.1016/j.jip.2024.108225","DOIUrl":"10.1016/j.jip.2024.108225","url":null,"abstract":"<div><div><em>Culex quinquefasciatus</em> is a hematophagous mosquito, widely distributed around the world, that plays a crucial role in public and veterinary health. As an efficient vector of etiological agents, it exhibits a marked preference for urban environments and human blood. Despite advances in mosquito-borne disease control, managing mosquito populations remains an economically efficient and safe strategy to reduce the impact of epidemic outbreaks. However, achieving this goal requires ecologically acceptable tools that ensure sustainability and minimize adverse environmental impacts. In the present work, we investigated the effect of a non-toxigenic model cyanobacterium on <em>Cx. quinquefasciatus</em> larvae through regulated cell death. We observed that heat stress treatment of <em>Synechocystis</em> PCC 6803 inducing ferroptosis, results in larval lipid oxidation, leading to their death. This effect can be mitigated by rearing larvae in an environment containing canonical inhibitors of ferroptosis, such as ferrostatin 1, or antioxidants, like glutathione and ascorbic acid. Furthermore, larval cell death induced by ferroptotic cyanobacteria is closely linked to oxidative dysregulation and lipid peroxidation, both hallmarks of ferroptosis. Moreover, while ferroptotic <em>Synechocystis</em> significantly affects larval development, it does not influence oviposition site selection by gravid females.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142502202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the role of RPL23 gene in active immunity of termite Reticulitermes chinensis against Metarhizium anisopliae","authors":"","doi":"10.1016/j.jip.2024.108226","DOIUrl":"10.1016/j.jip.2024.108226","url":null,"abstract":"<div><div>Ribosomal proteins are considered to be involved in the immunity of different animals against pathogens. The protein level of RPL23 increased after fungal infection in termites, but how it influence active immunity in termites is unknown. The role of <em>RPL23</em> gene was studied to evaluate its impact on active immunity of termite <em>Reticulitermes chinensis</em> against entomopathogenic fungus (EPF) <em>Metarhizium anisopliae</em>. The <em>RPL23</em> gene fragment (414 bp) was cloned and phylogenetic analysis revealed that it’s very close to termite <em>Coptotermes formosanus</em>. Expression of <em>RPL23</em> gene was significantly higher in abdomen as compared to thorax and head. Silencing <em>RPL23</em> gene had no significant impact on the frequency and time of allogrooming towards fungus exposed termites from nestmates, which showed that nestmates acquired spores from infected termites through allogrooming. Expression of immune genes (<em>GNBP1</em>, <em>GNBP2</em> and phenoloxidase) and apoptosis related genes (<em>TNF-α,</em> caspase 1, caspase 3 and caspase 8) decreased significantly in nestmates of fungus-treated termites after silencing of <em>RPL23</em> gene as compared to control. Antifungal activity and survival of <em>RPL23</em> silenced nestmates of fungus-treated termites also decreased. To sum up, this study found that silencing of <em>RPL23</em> gene broke the active immunity against <em>M. anisopliae</em> infection, reduced the antifungal activity of termites, weakened cell apoptosis, and led to increased mortality of termites, which may help to find a potential alternative for chemical insecticides to control termites.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142502201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Damage to the host cadaver, simulating the effects of scavenging, differentially affects fitness of entomopathogenic nematode species","authors":"","doi":"10.1016/j.jip.2024.108217","DOIUrl":"10.1016/j.jip.2024.108217","url":null,"abstract":"<div><div>Insect cadavers infected by entomopathogenic nematodes (EPN) are defended against scavengers by chemical mechanisms and other means. Despite these defences, the cadaver may be bitten before being rejected. In this study, we investigated the effect of damage to the cadaver cuticle on the fitness of nematodes (<em>Heterorhabditis downesi Stock, Griffin &amp; Burnell</em> or <em>Steinernema feltiae Filipjev</em>) developing inside. We first quantified the severity of scavenger damage to EPN-infected <em>Galleria mellonella</em> Linnaeus cadavers in the field, and separately, with crickets <em>(Gryllus bimaculatus</em> De Geer) in the laboratory. In both field and laboratory, EPN-infected cadavers suffered less damage than freeze-killed controls, and damage consisted mainly of small lesions to the cuticle. In further experiments, scavenging damage was simulated shortly after death of infected cadavers by piercing the cuticle 0, 1, 3 or 5 times and incubating in moist (100% relative humidity (RH)) or dry (60–70% RH) conditions. The greater the level of damage, the greater the loss of moisture from the cadaver (estimated by weight loss), and this was exacerbated in dry conditions. The number of infective juveniles (IJs) emerging from <em>H. downesi-</em>infected cadavers was significantly reduced by damage, especially in dry conditions. In addition, emerging IJs were progressively smaller with increasing damage. For this species, the number of IJs was negatively correlated with moisture loss, indicating that the reduction in fitness was mediated by desiccation. For <em>S. feltiae,</em> damage impacted IJ number to a lesser extent and size was not affected. The reduction in numbers was not explained by moisture loss, indicating that for <em>S. feltiae</em>, some factor other than desiccation (perhaps competition with opportunistic microbes) impacts the nematodes when the cuticle is damaged. The greater vulnerability of <em>H. downesi,</em> compared to <em>S. feltiae,</em> to scavenger damage to the host cadaver may be due to its longer developmental time in the host resulting in longer exposure to damaging conditions. In conclusion, damage simulating biting by scavengers impacts the fitness of EPN, with the effect depending on nematode species, environmental conditions and the extent of damage. These findings have implications for the success of field application of EPN in infected cadavers.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142467749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chitinase and proteinase K treatments enhance the DNA yield of microsporidium Ecytonucleospora hepatopenaei spores","authors":"","doi":"10.1016/j.jip.2024.108222","DOIUrl":"10.1016/j.jip.2024.108222","url":null,"abstract":"<div><div>Microsporidium <em>Ecytonucleospora hepatopenaei</em> (EHP) spores were purified from the hepatopancreas of <em>Penaeus vannamei</em> infected with EHP by percoll density gradient centrifugation and differential centrifugation. The EHP spores contain a thick chitin wall and might not rupture using the routine DNA extraction protocol. In this study, three enzymes were used, including chitinase, proteinase K, and DNase I. Chitinase or proteinase K digestions caused weakened fluorescence of chitin showing by a blurred edge of EHP spores stained with calcofluor white under a fluorescence microscope. Different combinations of these enzymes followed by DNA extraction with phenol–chloroform from EHP spores showed significant increases in the copy number of the EHP SSU gene per spore. The combination of the chitinase and proteinase K treatments resulted 4.46 ± 1.07 copies/spore detected, which is 31.6 ± 20.7 folds of no treatment groups, accounting to (55.7 ± 13.4)% of the total copies of the gene in the spore. The additional treatment with chitinase to the conventional extraction protocol with a proteinase K digestion step for feces and hepatopancreas samples of <em>P. vannamei</em> resulted in a significant difference in EHP copies in the DNA of (83.8 ± 64.1)% and (55.3 ± 88.0)% increases. The study proved that chitinase and proteinase K treatment enhance the DNA extraction from microsporidian spores resulting in high yield.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142467751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An alphabaculovirus from the zebra caterpillar, Melanchra picta Harris, is an isolate of species Alphabaculovirus maconfiguratae","authors":"","doi":"10.1016/j.jip.2024.108220","DOIUrl":"10.1016/j.jip.2024.108220","url":null,"abstract":"<div><div>A baculovirus had been previously identified in larvae of the zebra caterpillar, <em>Melanchra</em> (formerly <em>Ceramica</em>) <em>picta</em> Harris. To further characterize this virus, two isolates, Melanchra picta nucleopolyhedrovirus-185 (MepiNPV-185) and MepiNPV-600, were fully sequenced. Analysis of the genome sequences revealed that both isolates are members of alphabaculovirus species <em>Alphabaculovirus maconfiguratae</em>, along with alphabaculoviruses of the bertha armyworm, <em>Mamestra configurata</em> Walker. MepiNPV-600 displayed relatively low virulence against larvae of <em>Trichoplusia ni</em> Hübner in bioassays compared to other <em>T. ni</em>-pathogenic alphabaculoviruses. MepiNPV likely arose from a cross-species transfer between <em>M. configurata</em> and <em>M. picta</em> larvae, which often occur together.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142441075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}