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1.
Parasitology ; 151(5): 463-467, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38148679

RESUMO

Investigations of the parasites associated with extinct avian species provide unique insights into the ecology and evolution of both hosts and their parasitic counterparts. In the present paper, a new quill mite species, Peristerophila conuropsis sp. n., belonging to the family Syringophilidae (Prostigmata: Cheyletoidea) is described from the Carolina parakeet Conuropsis carolinensis Linnaeus (Psittaciformes: Psittacidae). This new species was collected from museum dry skin of the Carolina parakeet, the only native representative of the Psittacidae in the United States, which was an abundant resident of the southeastern and midwestern states and has been extinct in the beginning of the 20th century. Comment on the current taxonomic state and host associations of the genus Peristerophila are provided. Based on the host associations and habitats occupied by Peristerophila and related genera on parrots, it is hypothesized with the high probability that P. conuropsis has been extinct along with its host.


Assuntos
Doenças das Aves , Infestações por Ácaros , Ácaros , Animais , Ácaros/classificação , Ácaros/fisiologia , Doenças das Aves/parasitologia , Infestações por Ácaros/parasitologia , Infestações por Ácaros/veterinária , Infestações por Ácaros/epidemiologia , Periquitos/parasitologia , Interações Hospedeiro-Parasita , Feminino , Masculino , Ecossistema , Extinção Biológica
2.
Med Vet Entomol ; 38(2): 189-204, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38469668

RESUMO

We used entire mitochondrial (mt) genome sequences (14.5-15 kbp) to resolve the phylogeny of the four main lineages of the Haematobothrion ticks: Alloceraea, Archaeocroton, Bothriocroton and Haemaphysalis. In our phylogenetic trees, Alloceraea was the sister to Archaeocroton sphenodonti, a tick of an archetypal reptile, the tuatara, from New Zealand, to the exclusion of the rest of the species of Haemaphysalis. The mt genomes of all four of the Alloceraea species that have been sequenced so far had a substantial insert, 132-312 bp, between the tRNA-Glu (E) gene and the nad1 gene in their mt genomes. This insert was not found in any of the other eight subgenera of Haemaphysalis. The mt genomes of 13 species of Haemaphysalis from NCBI GenBank were added to the most recent data set on Haemaphysalis and its close relatives to help resolve the phylogeny of Haemaphysalis, including five new subgenera of Haemaphysalis not previously considered by other authors: Allophysalis (structurally primitive), Aboimisalis (structurally primitive), Herpetobia (structurally intermediate), Ornithophysalis (structurally advanced) and Segalia (structurally advanced). We elevated Alloceraea Schulze, 1919 to the status of genus because Alloceraea Schulze, 1919 is phylogenetically distinct from the other subgenera of Haemaphysalis. Moreover, we propose that the subgenus Allophysalis is the sister to the rest of the Haemaphysalis (14 subgenera) and that the 'structurally primitive' subgenera Hoogstraal and Kim comprise early diverging lineages. Our matrices of the pairwise genetic difference (percent) of mt genomes and partial 16S rRNA sequences indicated that the mt genome sequence of Al. kitaokai (gb# OM368280) may not be Al. kitaokai Hoogstraal, 1969 but rather another species of Alloceraea. In a similar way, the mt genome sequence of H. (Herpetobia) nepalensis Hoogstraal, 1962 (gb# NC_064124) was only 2% genetically different to that of H. (Allophysalis) tibetensis Hoogstraal, 1965 (gb# OM368293): this indicates to us that they are the same species. Alloceraea cretacea may be better placed in a genus other than Alloceraea Schulze, 1919. Reptiles may have been the host to the most recent common ancestor of Archaeocroton and Alloceraea.


Assuntos
Genoma Mitocondrial , Ixodidae , Filogenia , Animais , Ixodidae/genética , Ixodidae/classificação
3.
Parasitol Res ; 123(2): 120, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300369

RESUMO

We report the finding of five nymphs and three adult ticks attached to German tourists while traveling the American continents. All eight specimens were morphologically identified and confirmed genetically using the 16S rRNA gene and screened for Rickettsia spp. infections. Five tick species were identified: one Amblyomma mixtum nymph from Ecuador, one Amblyomma varium nymph from Colombia, three Amblyomma coelebs nymphs from Costa Rica, one Amblyomma americanum male from the USA, one Dermacentor andersoni female and one D. andersoni male from Canada. Tick-borne microorganisms screening using the pan-Rickettsia-PCR resulted in two positive and six negative ticks. The A. mixtum nymph was positive for Rickettsia amblyommatis, while the D. andersoni female was positive for Rickettsia peacockii.


Assuntos
Carrapatos , Animais , Feminino , Humanos , Masculino , Amblyomma , Ninfa , RNA Ribossômico 16S/genética , Carrapatos/classificação
4.
Exp Appl Acarol ; 93(2): 353-367, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38888667

RESUMO

Direct and indirect ecological interactions, environmental factors, and the phenology of host plants can shape the way mites interact. These relationships interfere with species occurrence and consequently alter the structure and stability of the intraplant community. As predatory mites act as regulators of herbivorous mites, we hypothesized that these mites may occupy a central position in a network of interactions among mite species associated with mango trees, and the occurrence of these species is mediated by environmental variables and the phenological stage of the host plant. We evaluated the global structure of the interaction network of mites associated with individual Mangifera indica plants and analyzed the interspecific relationships of the species using an undirected Bayesian network approach. Additionally, we observed a correlation between mite population density and plant phenological stage. Environmental variables, such as average monthly temperature, monthly precipitation, and average monthly relative humidity at different sampling date were used in the correlation analysis. The modularity at the mite-plant network level showed a low specialization index H2 = 0.073 (generalist) and high robustness (R = 0.93). Network analysis revealed that Amblyseius largoensis, Bdella ueckermanni, Parapronematus acaciae, and Tuckerella ornata occupied central positions in the assembly of mites occurring on mango trees. Environmental variables, average monthly temperature, and monthly precipitation were correlated with the occurrence of Brachytydeus formosa, Cisaberoptus kenyae, Oligonychus punicae, T. ornata, and Vilaia pamithus. We also observed a correlation between the plant phenological stage and population densities of Neoseiulus houstoni, O. punicae, P. acaciae, and V. pamithus.


Assuntos
Mangifera , Ácaros , Mangifera/parasitologia , Animais , Ácaros/fisiologia , Densidade Demográfica , Cadeia Alimentar , Teorema de Bayes
5.
Annu Rev Entomol ; 68: 69-88, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36170643

RESUMO

Mites are masters at attaching to larger animals, often insects, in a temporary symbiosis called phoresy that allows these tiny animals to exploit patchy resources. In this article, we examine phoresy in the Acari, including those that feed on their carriers in transit, from a broad perspective. From a phylogenetic perspective, phoresy has evolved several times from free-living ancestors but also has been lost frequently. Rotting logs appear to be the first patchy resource exploited by phoretic mites, but the evolution of rapid life cycles later permitted exploitation of short-lived resources. As phoresy is a temporary symbiosis, most species have off-host interactions with their carrier. These relationships can be highly complex and context dependent but often are exploitative of the carrier's resources or progeny. Transitions from phoresy to parasitism seem widespread, but evidence for transitions from obligate phoretic parasitism to permanent parasitism is weak.


Assuntos
Ácaros , Animais , Filogenia , Estágios do Ciclo de Vida , Simbiose
6.
Mol Biol Evol ; 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35724423

RESUMO

Most humans carry mites in the hair follicles of their skin for their entire lives. Follicular mites are the only metazoans tha continuously live on humans. We propose that Demodex folliculorum (Acari) represents a transitional stage from a host-injuring obligate parasite to an obligate symbiont. Here, we describe the profound impact of this transition on the genome and physiology of the mite. Genome sequencing revealed that the permanent host association of D. folliculorum led to an extensive genome reduction through relaxed selection and genetic drift, resulting in the smallest number of protein-coding genes yet identified among panarthropods. Confocal microscopy revealed that this gene loss coincided with an extreme reduction in the number of cells. Single uninucleate muscle cells are sufficient to operate each of the three segments that form each walking leg. While it has been assumed that the reduction of the cell number in parasites starts early in development, we identified a greater total number of cells in the last developmental stage (nymph) than in the terminal adult stage, suggesting that reduction starts at the adult or ultimate stage of development. This is the first evolutionary step in an arthropod species adopting a reductive, parasitic or endosymbiotic lifestyle. Somatic nuclei show underreplication at the diploid stage. Novel eye structures or photoreceptors as well as a unique human host melatonin-guided day/night rhythm are proposed for the first time. The loss of DNA repair genes coupled with extreme endogamy might have set this mite species on an evolutionary dead-end trajectory.

7.
Med Vet Entomol ; 37(3): 425-459, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37144688

RESUMO

In the Mediterranean basin, the tick species Hyalomma lusitanicum Koch stands out among other species of the Hyalomma genus due to its wide distribution, and there is great concern about its potential role as a vector and/or reservoir and its continuous expansion to new areas because of climate warming and human and other animal movements. This review aims to consolidate all the information on H. lusitanicum, including taxonomy and evolution, morphological and molecular identification, life cycle, sampling methods, rearing under laboratory conditions, ecology, hosts, geographical distribution, seasonality, vector role and control methods. The availability of adequate data is extremely relevant to the development of appropriate control strategies in areas where this tick is currently distributed as well as in new areas where it could become established in the near future.


Assuntos
Ixodidae , Carrapatos , Animais , Humanos , Clima
8.
Med Vet Entomol ; 37(4): 631-646, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37401856

RESUMO

Pest management in farm animals is an important action to contain economic damage to livestock production and prevent transmission of severe diseases to the stock. The use of chemical insecticides is still the most common approach followed by farmers; however, avoiding possible toxic effects on animals is a fundamental task for pest control measures compatible with animal well-being. Moreover, legal constraints and insurgence of resistance by target species to the available insecticidal compounds are increasingly complicating farmers' operations. Alternatives to chemical pesticides have been explored with some promising results in the area of biological control or the use of natural products as sprays. The application of RNA interference techniques has enabled the production of new means of pest control in agriculture, and it is opening a promising avenue for controlling arthropod pests of livestock. Transcript depletion of specific target genes of the recipient organisms is based on the action of double-strand RNAs (dsRNA) capable of impairing the production of fundamental proteins. Their mode of action, based on the specific recognition of short genomic sequences, is expected to be highly selective towards non-target organisms potentially exposed; in addition, there are physical and chemical barriers to dsRNA uptake by mammalian cells that render these products practically innocuous for higher animals. Summarising existing literature on gene silencing for main taxa of arthropod pests of livestock (Acarina, Diptera, Blattoidea), this review explores the perspectives of practical applications of dsRNA-based pesticides against the main pests of farm animals. Knowledge gaps are summarised to stimulate additional research in this area.


Assuntos
Artrópodes , Inseticidas , Praguicidas , Animais , Gado , Fazendas , Interferência de RNA , Mamíferos
9.
Exp Appl Acarol ; 91(3): 413-427, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37861891

RESUMO

Tetranychus urticae Koch (Acari: Tetranychidae), the two-spotted spider mite, is a pest that limits strawberry production in Mexico. Little is known about the interactions that occur between T. urticae and healthy strawberry plants or strawberry plants infested by conspecific spider mites. Therefore, in this study we evaluated the attraction of T. urticae to healthy strawberry plants mediated by volatile organic compounds (VOCs), and to plants damaged by conspecifics mediated by herbivore-induce plant volatiles (HIPVs). First, we conducted dual-choice tests using a Y-tube olfactometer with plants and extracts obtained through dynamic aeration. The volatile composition of the extracts was identified using gas chromatography-mass spectrometry (GC-MS). Once the compounds were identified, we also conducted dual-choice tests with selected synthetic compounds. Tetranychus urticae exhibited greater attraction to both healthy and damaged plants compared to the control (clean air). However, when healthy and damaged plants were offered simultaneously, there was no significant preference observed. Bioassays with extracts obtained by dynamic aeration yielded similar results. The identified compounds were terpenes and aromatic hydrocarbons. We found qualitative and quantitative changes between the VOCs emitted by the healthy plant and the HIPVs from mite-damaged plants. The individual compounds α-pinene (10 ng), pseudocumene (10 ng), and limonene (1 ng) and 10 ng of the blend made of α-pinene + pseudocumene + mesitylene + limonene (5:34:57:4) attracted more T. urticae than the control. However, the binary blend of pseudocumene + limonene (91:9) was more attractive than the other binary or three-compound blends evaluated. These results may contribute to developing strategies for the management of this pest.


Assuntos
Fragaria , Tetranychidae , Compostos Orgânicos Voláteis , Animais , Sinais (Psicologia) , Limoneno , Plantas
10.
Exp Appl Acarol ; 89(3-4): 461-473, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37115465

RESUMO

Questing ticks are usually collected by flagging or dragging. Mostly exophilic tick species are caught, such as Ixodes ricinus, the most common tick in Central Europe. In the present study, ticks collected from underground environments in the Grand Duchy of Luxembourg and in the Central German Uplands (Federal States of Hesse, Bavaria, Thuringia, Baden-Wuerttemberg, Rhineland-Palatinate, Saarland and Northrhine-Westphalia) were investigated. Six tick species were revealed among the 396 analyzed specimens: Ixodes ariadnae, Ixodes canisuga, Ixodes hexagonus, I. ricinus, Ixodes trianguliceps, and Dermacentor marginatus. Adults and immatures of I. hexagonus dominated the findings (57% of all specimens), especially in shelters acting as potential resting places of main hosts. Ixodes canisuga and I. trianguliceps were for the first time recorded in Luxembourg, and one nymph of the bat tick I. ariadnae represents only the second report for Germany. Collecting ticks in subterranean environments turned out to be a useful approach to increase knowledge about the occurrence of relatively rare tick species, including those that spend most of their lifetime on their hosts, but detach in such environmental settings.


Assuntos
Ixodes , Infestações por Carrapato , Masculino , Animais , Feminino , Luxemburgo , Infestações por Carrapato/epidemiologia , Europa (Continente) , Alemanha/epidemiologia , Ninfa
11.
Exp Appl Acarol ; 91(1): 99-110, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37584844

RESUMO

Soft ticks from the Ornithodoros genus are vectors of relapsing fever (RF) spirochetes around the world. In Mexico, they were originally described in the 19th century. However, few recent surveillance studies have been conducted in Mexico, and regions where RF spirochetes circulate remain vague. Here, the presence of soft ticks in populated areas was assessed in two sites from the Mexican states of Aguascalientes and Zacatecas. Argasidae ticks were collected, identified by morphology and mitochondrial 16S rDNA gene sequencing, and tested for RF borreliae. The specimens in both sites were identified as Ornithodoros turicata but no RF spirochetes were detected. These findings emphasize the need to update the distribution of these ticks in multiple regions of Mexico and to determine the circulation of RF borreliosis in humans and domestic animals.


Assuntos
Argasidae , Borrelia , Ornithodoros , Febre Recorrente , Humanos , Animais , Febre Recorrente/epidemiologia , Borrelia/genética , Animais Domésticos
12.
Exp Appl Acarol ; 90(3-4): 247-266, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37470937

RESUMO

An incomplete species recognition system may cause reproductive interference. Interspecific mating between Panonychus citri and Panonychus osmanthi produced apparently normal F1 hybrid females. However, the F1 females laid few eggs, and the produced eggs did not hatch (suggesting hybrid breakdown). Several common host plants of P. citri and P. osmanthi have been determined, including Japanese pear, peach, and citrus. However, P. osmanthi has been found only on its particular host plants in the genus Osmanthus. To assess the potential for reproductive interference between P. citri and P. osmanthi, we evaluated the competitiveness (1 ♀ × 2 ♂♂) and preference (2 ♀♀ × 1 ♂) of males in mating and guarding behavior and assessed the effect of second mating on offspring paternity using Japanese pear leaf disks. We found that P. citri males were superior competitors. Moreover, the species recognition ability of P. citri males was lower than that of P. osmanthi males, and frequent occurrence of reproductive interference should therefore be expected. In a mixed population (2 ♀♀ × 2 ♂♂), 41% of females copulated with heterospecific males, although the mating superiority of P. citri was not proven. The ratio of effective second mating with conspecific males after heterospecific mating was higher in the crosses to P. citri females (77.8%) than P. osmanthi females (14.3%). Therefore, P. citri females had more chance than P. osmanthi females to recover from the fitness cost imposed by heterospecific mating through subsequent conspecific mating. To date, P. osmanthi has not been detected on host plants other than Osmanthus species. Reproductive interference by P. citri males may therefore narrow the range of host plants available for P. osmanthi.


Assuntos
Citrus , Tetranychidae , Masculino , Feminino , Animais , Reprodução , Especificidade da Espécie
13.
Exp Appl Acarol ; 91(3): 439-461, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37870736

RESUMO

Chiggers are common ectoparasites and the exclusive vector of scrub typhus. Based on previous investigations from a unique geographical area in Yunnan Province of southwest China, the Three Parallel Rivers Area, we retrospectively studied the species diversity and related ecology of chiggers on rodents and other small mammals. A very high species diversity of 120 chigger species was identified. Five dominant chigger species accounted for 59.4% (5238/8965) of total chiggers, and among them Leptotrombidium scutellare is the second major vector of scrub typhus in China. Species diversity of the chigger community fluctuates greatly in different altitudinal and latitudinal gradients. There are significant differences in species composition, species diversity and dominant species of chiggers among hosts with apparent community heterogeneity. Based on the species abundance distribution, the expected total number of chigger species was estimated to be 170, 50 more than the number of actually collected species; this further indicates a very high chigger species diversity in this area. The bipartite ecological network analysis revealed the intricate relationships between chigger and host species-positive and negative correlations existed among some species of dominant and vector chiggers.


Assuntos
Infestações por Ácaros , Doenças dos Roedores , Tifo por Ácaros , Trombiculidae , Animais , Estudos Retrospectivos , China , Mamíferos/parasitologia , Infestações por Ácaros/parasitologia , Roedores/parasitologia
14.
Exp Appl Acarol ; 91(2): 139-235, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37676375

RESUMO

The physics of fluid laminar flow through an idealised deutosternum assembly is used for the first time to review predatory feeding designs over 72 different-sized example species from 16 mesostigmatid families in order to inform the finding of new biological control agents. Gnathosomal data are digitised from published sources. Relevant gnathosomal macro- and micro-features are compared and contrasted in detail which may subtly impact the control of channel- or 'pipe'-based transport of prey liquids around various gnathosomal locations. Relative deutosternal groove width on the mesostigmatid subcapitulum is important but appears unrelated to the closing velocity ratio of the moveable digit. Big mites are adapted for handling large and watery prey. The repeated regular distance between deutosternal transverse ridges ('Querleisten') supports the idea of them enabling a regular fluctuating bulging or pulsing droplet-based fluid wave 'sticking' and 'slipping' along the groove. Phytoseiids are an outlier functional group with a low deutosternal pipe flow per body size designed for slot-like microchannel transport in low volume fluid threads arising from daintily nibbling nearby prey klinorhynchidly. Deutosternal groove denticles are orientated topographically in order to synergise flow and possible mixing of coxal gland-derived droplets and circumcapitular reservoir fluids across the venter of the gnathosomal base back via the hypostome to the prey being masticated by the chelicerae. As well as working with the tritosternum to mechanically clean the deutosternum, denticles may suppress fluid drag. Shallow grooves may support edge-crawling viscous flow. Lateral features may facilitate handling unusual amounts of fluid arising from opportunistic feeding on atypical prey. Various conjectures for confirmatory follow-up are highlighted. Suggestions as to how to triage non-uropodoid species as candidate plant pest control agents are included.


Assuntos
Calcificações da Polpa Dentária , Ácaros , Humanos , Animais , Agentes de Controle Biológico , Controle Biológico de Vetores , Comportamento Predatório
15.
Mol Ecol ; 31(15): 4078-4094, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35665980

RESUMO

Most of our understanding of island diversity comes from the study of aboveground systems, while the patterns and processes of diversification and community assembly for belowground biotas remain poorly understood. Here, we take advantage of a relatively young and dynamic oceanic island to advance our understanding of ecoevolutionary processes driving community assembly within soil mesofauna. Using whole organism community DNA (wocDNA) metabarcoding and the recently developed metaMATE pipeline, we have generated spatially explicit and reliable haplotype-level DNA sequence data for soil mesofaunal assemblages sampled across the four main habitats within the island of Tenerife. Community ecological and metaphylogeographic analyses have been performed at multiple levels of genetic similarity, from haplotypes to species and supraspecific groupings. Broadly consistent patterns of local-scale species richness across different insular habitats have been found, whereas local insular richness is lower than in continental settings. Our results reveal an important role for niche conservatism as a driver of insular community assembly of soil mesofauna, with only limited evidence for habitat shifts promoting diversification. Furthermore, support is found for a fundamental role of habitat in the assembly of soil mesofauna, where habitat specialism is mainly due to colonization and the establishment of preadapted species. Hierarchical patterns of distance decay at the community level and metaphylogeographical analyses support a pattern of geographic structuring over limited spatial scales, from the level of haplotypes through to species and lineages, as expected for taxa with strong dispersal limitations. Our results demonstrate the potential for wocDNA metabarcoding to advance our understanding of biodiversity.


Assuntos
Código de Barras de DNA Taxonômico , Solo , Biodiversidade , DNA , Ecossistema , Haplótipos/genética
16.
Exp Parasitol ; 235: 108215, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35090869

RESUMO

Formulations of the entomopathogenic fungus Beauveria bassiana (Hypocreales: Cordycipitaceae) were tested under field conditions against the bovine tick adults Rhipicephalus microplus (Acari: Ixodidae). Formulations were prepared for each fungal isolate consisting of 108 conidia.mL-1, 10% avocado oil and either of Ballista® or Break-thru® as an adjuvant sprayed on tick-infested cows. The following variables were evaluated: initial female weight, egg mass, hatching percentage, egg production index, nutritional index, reproductive efficiency and mortality. After about four days, the ticks were collected to estimate all the variables mentioned above. Mortality for treated ticks ranged from 13 to 38%. All isolate formulations significantly reduced egg mass, hatching percentage of the eggs, egg production index, nutritional index and reproductive efficiency. The current study demonstrated the potential of B. bassiana formulations for the biological control of R. microplus under environmental field conditions.


Assuntos
Beauveria , Hypocreales , Ixodidae , Rhipicephalus , Animais , Bovinos , Feminino , Controle Biológico de Vetores , Rhipicephalus/microbiologia
17.
Ecotoxicology ; 31(9): 1450-1461, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36319919

RESUMO

The use of pesticides to protect crops often affects non-target organisms vital to ecosystem functioning. A functional soil mesofauna is important for decomposition and nutrient cycling processes in agricultural soils, which generally have low biodiversity. To assess pesticide effects on natural soil communities we enclosed intact soil cores in situ in an agricultural field in 5 cm wide mesocosms. We used two types of mesh lids on the mesocosms, allowing or preventing migration of mesofauna. The mesocosms were exposed to the insecticide imidacloprid (0, 0.1, 1, and 10 mg/kg dry soil) and left in the field for 20 days. Overall, regardless of lid type, mesocosm enclosure did not affect springtail or mite abundances during the experiment when compared with undisturbed soil. Imidacloprid exposure reduced the abundance of both surface- and soil-living springtails in a concentration-dependent manner, by 65-90% at the two highest concentrations, and 21-23% at 0.1 mg/kg, a concentration found in some agricultural soils after pesticide application. Surface-living springtails were more affected by imidacloprid exposure than soil-living ones. In contrast, neither predatory nor saprotrophic mites showed imidacloprid-dependent changes in abundance, concurring with previous findings indicating that mites are generally less sensitive to neonicotinoids than other soil organisms. The possibility to migrate did not affect the springtail or mite abundance responses to imidacloprid. We show that under realistic exposure concentrations in the field, soil arthropod community composition and abundance can be substantially altered in an organism-dependent manner, thus affecting the soil community diversity.


Assuntos
Ácaros , Praguicidas , Animais , Praguicidas/toxicidade , Ecossistema , Neonicotinoides/toxicidade , Solo
18.
Pestic Biochem Physiol ; 181: 105000, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35082027

RESUMO

Pyridaben is a mitochondrial electron transport complex I inhibitor. The H110R mutation in the PSST subunit has been reported as a major factor in pyridaben resistance in the two-spotted spider mite, Tetranychus urticae. However, backcross experiments revealed that the mutant PSST alone conferred only moderate resistance. In contrast, inhibition of cytochrome P450 (CYP) markedly reduces resistance levels in a number of highly resistant strains. It was reported previously that maternal factors contributed to the inheritance of pyridaben resistance in the egg stage, but the underlying mechanisms have yet to be elucidated. Here, we studied the combined effects of the PSST H110R mutation and candidate CYPs, as metabolic resistance factors, on pyridaben resistance in T. urticae. We found that the maternal effects of inheritance of resistance in the egg stage were associated with CYP activity. Analysis of differential gene expression by RNA-seq identified CYP392A3 as a candidate causal factor for the high resistance level. Congenic strains, where the alleles of both PSST and CYP392A3 were derived from a resistant strain (RR_i; i = 1 or 2) and a susceptible strain (SS_i) in a common susceptible genetic background, were constructed by marker-assisted backcrossing. RR_i showed upregulation of CYP392A3 and high resistance levels (LC50 > 10,000 mg L-1), while SS_i had LC50 < 10 mg L-1. To disentangle the individual effects of PSST and CYP392A3 alleles, we also attempted to uncouple these genes in RR_i. We conclude that given the variation in LC50 values and expression levels of CYP392A3 in the congenic and uncoupled strains, it is likely that the high pyridaben resistance levels are due to a synergistic or cumulative effect of the combination of mutant PSST and associated CYPs, including CYP392A3, but other yet to be discovered factors cannot be excluded.


Assuntos
Acaricidas , Tetranychidae , Acaricidas/farmacologia , Animais , Sistema Enzimático do Citocromo P-450/genética , Mutação , Piridazinas , Tetranychidae/genética
19.
Exp Appl Acarol ; 86(3): 327-342, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35286552

RESUMO

The intrinsic rate of natural increase of a population (rm) has been in focus as a key parameter in entomology and acarology. It is considered especially important in studies of predators that are potential biological control agents of fast-growing pests such as mites, whiteflies and thrips. Life-table experiments under controlled laboratory conditions are standard procedures to estimate rm. However, such experiments are often time consuming and may critically depend on the precise assessment of the developmental time and the fecundity rate early in the reproductive phase. Using selected studies of predatory mites with suitable life-table data, we investigated whether and how measurements of growth rates can be simplified. We propose a new method for estimating rm from partial life tables, in which the researcher can choose a level of precision based on a stand-in measure of relative error. Based on this choice, the procedure helps the researcher to decide when a life-table experiment can be terminated. Depending on the chosen precision, significant amounts of experimental time can be saved without seriously compromising the reliability of the estimated growth parameter.


Assuntos
Artrópodes , Ácaros , Animais , Tábuas de Vida , Controle Biológico de Vetores/métodos , Comportamento Predatório , Reprodutibilidade dos Testes
20.
Exp Appl Acarol ; 87(1): 49-65, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35817881

RESUMO

To determine whether the mites used in the ripening process of traditional cheeses are genetically unique to cheese factories, we investigated mites from three types of traditional cheeses, that use mites in the ripening process: 'Würchwitzer Milbenkäse' from Germany and 'Mimolette' and 'Artisou' from France. In addition, traditional ripened cheeses were purchased from cheese specialty stores in France (Mimolette) and Japan ('Laguiole' from France) as well as stores in temporary markets in France ('Salers' and 'Cantal vieux') and the mites obtained from those cheeses were analyzed in this study. Partial sequences of the 28S rRNA gene (28S) were determined and used to reconstruct a phylogenetic tree. Tyrolichus casei, the dominant cheese mite species from the ripening cabinets of three traditional cheese producers and two cheese specialty stores in France and Japan, had identical partial 28S sequences. All specimens from Cantal vieux from a store in the temporary market in France had an identical sequence with Acarus siro and Acarus immobilis in the determined region of the 28S sequences. Mite individuals from Salers from a store in the temporary markets in France shared the same haplotype as Acotyledon paradoxa. For the T. casei individuals from five different localities (19 individuals in total), the nuclear loci were obtained using MIG-seq. More than several thousand genomic regions are amplified simultaneously by multiplex PCR, and targeting regions surrounded by inter-simple sequence repeats (ISSRs) in the genome were sequenced using the MiSeq system (Illumina). SNPs extracted from this genome-wide analysis showed that no genetic structure existed in the populations from any region. Among the five samples from the three regions, which were more than 500 km apart and from completely different environments, the mites had no geographic bias, but all mite individuals were genetically nearly identical. Thus, we found no evidence to support the existence of 'cheese factory-specific' T. casei mites, at least in terms of genetic analysis.


Assuntos
Acaridae , Queijo , Ácaros , Acaridae/genética , Animais , Queijo/análise , Ácaros/genética , Filogenia , RNA Ribossômico 28S/química
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