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1.
J Fish Biol ; 102(4): 977-991, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36744697

RESUMO

We studied the reproductive strategy, sexual system and growth of dientudo paraguayo Acestrorhynchus pantaneiro. After 2 years of monitoring in shallow areas of a floodplain lake from the lower Paraná basin (Argentina), it was evidenced that water temperature modulated gonadal maturation, but it was the river water level the synchronising stimulus that triggered spawning. This species exhibited a single annual breeding period from October to January, with most spawning activity in November. According to the von Bertalanffy growth curve, fish would reach autumn to winter months with LS of ~120 mm, already mature males. The first mature females were found at LS of 210 mm, becoming sexually mature between the second and third breeding seasons. This is the first integrative study that includes the body-length frequency distribution and sex differential size at first maturity and growth, and reports the presence of intersex gonads questioning its sexual pattern from gonochoristic to sequential hermaphrodite species. The sexual pattern, the multiple spawning behaviour and a medium to high absolute fecundity support the opportunistic and invasive behavior observed in previous contributions for this characiform species.


Assuntos
Caraciformes , Feminino , Masculino , Animais , Maturidade Sexual , Reprodução , Fertilidade , Gônadas , Estações do Ano , Biologia
2.
Animals (Basel) ; 13(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36830486

RESUMO

For thousands of years, dogs have coexisted with humans and have been adopted as companion pets and working animals. The communication between humans and dogs has improved their coexistence and socialization; however, due to the nature of their activities, dogs and humans occasionally lose face-to-face contact. The purpose of this scoping review is to examine five essential aspects of current technology designed to support intentional communication between humans and dogs in scenarios where there is no face-to-face contact: (1) the technologies used, (2) the activity supported, (3) the interaction modality, (4) the evaluation procedures, and the results obtained, and (5) the main limitations. In addition, this article explores future directions for research and practice. The PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) guidelines were followed when conducting the review. Scopus (Elsevier), Springer-Link, IEEE Xplorer, ACM Digital Library, and Science Direct were used as data sources to retrieve information from January 2010 to March 2022. The titles and abstracts were individually reviewed by the authors (L.R.-V., I.E.E.-C., and H.P.-E.), and the full articles were then examined before a final inclusion determination. 15 (3%) out of the 571 records that were obtained met the requirements for inclusion. The most used technologies for dogs are: (1) 71% of technologies focused on generating messages are wearable devices equipped with sensors (bite, tug, or gesture), (2) 60% of technologies focused on receiving messages are wearable devices equipped with vibrotactile actuators, and (3) 100% of technologies focused on bidirectional communication are videochats. 67% of the works are oriented to support search and assistance tasks. 80% of the works developed technology for one-way communication. 53% of the technologies have a haptic dog interaction modality, that is, there is an object that the dog must wear or manipulate in a certain way. All of the reported evaluations were pilot studies with positive feasibility results. Remote human-dog interaction technology holds significant promise and potential; however, more research is required to assess their usability and efficacy and to incorporate new technological developments.

3.
Environ Entomol ; 52(1): 98-107, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36585828

RESUMO

Bactericera cockerelli (Sulc) (Hemiptera: Triozidae) is a vector of 'Candidatus Liberibacter solanacearum' (Lso), the pathogen that causes potato zebra chip. Zebra chip incidence varies regionally, perhaps because of geographic differences in species of noncrop hosts available to the vector and in susceptibility of those hosts to Lso. Native and introduced species of Lycium (Solanales: Solanaceae) are important noncrop hosts of B. cockerelli in some regions of North America. Susceptibility of native Lycium species to Lso is uncertain. We investigated the use of two native species of Lycium by B. cockerelli in South Texas and tested whether they are susceptible to Lso. Bactericera cockerelli adults and nymphs were collected frequently from L. berlandieri Dunal and L. carolinianum Walter. Greenhouse assays confirmed that B. cockerelli develops on both species and showed that Lso infects L. carolinianum. Molecular gut content analysis provided evidence that B. cockerelli adults disperse between potato and Lycium. These results demonstrate that L. berlandieri and L. carolinianum are likely noncrop sources of potato-colonizing B. cockerelli in South Texas and that L. carolinianum is a potential source of Lso-infected psyllids. We also routinely collected the congeneric psyllid, Bactericera dorsalis (Crawford), from both Lycium species. These records are the first for this psyllid in Texas. Bactericera dorsalis completed development on both native Lycium species, albeit with high rates of mortality on L. berlandieri. B. dorsalis acquired and transmitted Lso on L. carolinianum under greenhouse conditions but did not transmit Lso to potato. These results document a previously unknown vector of Lso.


Assuntos
Hemípteros , Lycium , Rhizobiaceae , Solanum tuberosum , Animais , Solanales , Texas , Doenças das Plantas
4.
Sci Rep ; 12(1): 2325, 2022 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-35149738

RESUMO

Many parasites of seasonally available hosts must persist through times of the year when hosts are unavailable. In tropical environments, host availability is often linked to rainfall, and adaptations of parasites to dry periods remain understudied. The bird-parasitic fly Philornis downsi has invaded the Galapagos Islands and is causing high mortality of Darwin's finches and other bird species, and the mechanisms by which it was able to invade the islands are of great interest to conservationists. In the dry lowlands, this fly persists over a seven-month cool season when availability of hosts is very limited. We tested the hypothesis that adult flies could survive from one bird-breeding season until the next by using a pterin-based age-grading method to estimate the age of P. downsi captured during and between bird-breeding seasons. This study showed that significantly older flies were present towards the end of the cool season, with ~ 5% of captured females exhibiting estimated ages greater than seven months. However, younger flies also occurred during the cool season suggesting that some fly reproduction occurs when host availability is low. We discuss the possible ecological mechanisms that could allow for such a mixed strategy.


Assuntos
Aves/parasitologia , Cruzamento , Interações Hospedeiro-Parasita , Muscidae/fisiologia , Envelhecimento , Animais , Aves/fisiologia , Diapausa/fisiologia , Equador , Feminino , Estágios do Ciclo de Vida , Masculino , Pupa , Estações do Ano
5.
BMC Vet Res ; 17(1): 49, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33494772

RESUMO

BACKGROUND: Borrelia burgdorferi is the spirochete that causes Lyme Borreliosis (LB), which is a zoonotic tick-borne disease of humans and domestic animals. Hard ticks are obligate haematophagous ectoparasites that serve as vectors of Borrelia burgdorferi. Studies on the presence of Lyme borreliosis in Egyptian animals and associated ticks are scarce. METHODS: This study was conducted to detect B. burgdorferi in different tick vectors and animal hosts. Three hundred animals (dogs=100, cattle=100, and camels=100) were inspected for tick infestation. Blood samples from 160 tick-infested animals and their associated ticks (n=1025) were collected and examined for the infection with B. burgdorferi by polymerase chain reaction (PCR) and sequencing of the 16S rRNA gene. The identified tick species were characterized molecularly by PCR and sequencing of the ITS2 region. RESULTS: The overall tick infestation rate among examined animals was 78.33% (235/300). The rate of infestation was significantly higher in camels (90%), followed by cattle (76%) and dogs (69%); (P = 0.001). Rhipicephalus sanguineus, Rhipicephalus (Boophilus) annulatus, and both Hyalomma dromedarii and Amblyomma variegatum, were morphologically identified from infested dogs, cattle, and camels; respectively. Molecular characterization of ticks using the ITS2 region confirmed the morphological identification, as well as displayed high similarities of R. sanguineus, H. dromedarii, and A. Variegatu with ticks identified in Egypt and various continents worldwide. Just one dog (1.67%) and its associated tick pool of R. sanguineus were positive for B. burgdorferi infection. The 16S rRNA gene sequence for B. burgdorferi in dog and R. sanguineus tick pool showed a 100% homology. CONCLUSION: Analyzed data revealed a relatively low rate of B. burgdorferi infection, but a significantly high prevalence of tick infestation among domesticated animals in Egypt, which possesses a potential animal and public health risk. Additionally, molecular characterization of ticks using the ITS2 region was a reliable tool to discriminate species of ticks and confirmed the morphological identification.


Assuntos
Borrelia burgdorferi , Doenças do Cão/epidemiologia , Doença de Lyme/veterinária , Infestações por Carrapato/veterinária , Amblyomma/genética , Amblyomma/microbiologia , Animais , Camelus/microbiologia , Camelus/parasitologia , Bovinos/microbiologia , Bovinos/parasitologia , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães/microbiologia , Cães/parasitologia , Egito/epidemiologia , Doença de Lyme/epidemiologia , Filogenia , Rhipicephalus sanguineus/genética , Rhipicephalus sanguineus/microbiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/microbiologia , Carrapatos/genética , Carrapatos/microbiologia
6.
J Insect Behav ; 34(5-6): 296-311, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35153376

RESUMO

The Avian Vampire Fly, Philornis downsi, has invaded the Galapagos Islands, where it causes high mortality of endemic and native landbird species, including most species of Darwin's finches. Control methods are under development, but key information is missing about the reproductive biology of P. downsi and the behavior of flies in and near nests of their hosts. We used external and internal nest cameras to record the behavior of P. downsi adults within and outside nests of the Galapagos Flycatcher, Myiarchus magnirostris, throughout all stages of the nesting cycle. These recordings showed that P. downsi visited flycatcher nests throughout the day with higher fly activity during the nestling phase during vespertine hours. The observations also revealed that multiple P. downsi individuals can visit nests concurrently, and that there are some interactions among these flies within the nest. Fly visitation to nests occurred significantly more often while parent birds were away from the nest than in the nest, and this timing appears to be a strategy to avoid predation by parent birds. We report fly mating behavior outside the nest but not in the nest cavity. We discuss the relevance of these findings for the adaptive forces shaping P. downsi life history strategies as well as rearing and control measures. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10905-021-09789-7.

7.
Nat Commun ; 11(1): 5802, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33199718

RESUMO

A major bottleneck in identifying therapies to control citrus greening and other devastating plant diseases caused by fastidious pathogens is our inability to culture the pathogens in defined media or axenic cultures. As such, conventional approaches for antimicrobial evaluation (genetic or chemical) rely on time-consuming, low-throughput and inherently variable whole-plant assays. Here, we report that plant hairy roots support the growth of fastidious pathogens like Candidatus Liberibacter spp., the presumptive causal agents of citrus greening, potato zebra chip and tomato vein greening diseases. Importantly, we leverage the microbial hairy roots for rapid, reproducible efficacy screening of multiple therapies. We identify six antimicrobial peptides, two plant immune regulators and eight chemicals which inhibit Candidatus Liberibacter spp. in plant tissues. The antimicrobials, either singly or in combination, can be used as near- and long-term therapies to control citrus greening, potato zebra chip and tomato vein greening diseases.


Assuntos
Anti-Infecciosos/farmacologia , Ensaios de Triagem em Larga Escala , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Rhizobiaceae/fisiologia , Sequência de Bases , Citrus/efeitos dos fármacos , Citrus/microbiologia , Edição de Genes , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/microbiologia , Doenças das Plantas/microbiologia , Raízes de Plantas/genética , Rhizobiaceae/efeitos dos fármacos , Solanum tuberosum/efeitos dos fármacos , Solanum tuberosum/microbiologia , Transgenes
8.
J Econ Entomol ; 113(5): 2079-2085, 2020 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-32651952

RESUMO

Our previous study provided correlative evidence that morning glory species harboring endophytic fungi (Periglandula) are resistant to potato psyllid [Bactericera cockerelli (Sulc)], whereas species free of fungi often allowed psyllid development. In this study, we manipulated levels of ergot alkaloids in host tissues by inoculating clippings from potato plants with extracts from morning glories that harbor Periglandula [Ipomoea leptophylla Torrey, Ipomoea imperati (Vahl) Grisebach, Ipomoea tricolor Cavanilles, Ipomoea pandurata (L.) G. F. Meyer, and Turbina corymbosa (L.)] and one species (Ipomoea alba L.) that does not harbor the endophyte. Ergot alkaloids (clavines, lysergic acid amides, and ergopeptines) were detected in potato clippings, thus confirming that leaves had taken up compounds from solutions of crude extracts. Psyllid mortality rates on inoculated clippings ranged between 53 and 93% in treatments producing biochemically detectable levels of alkaloids, when compared with 15% mortality in water controls or the alkaloid-free I. alba. We then tested synthetic analogs from each of the three alkaloid classes that had been detected in the crude extracts. Each compound was assayed by inoculating clippings of two host species (potato and tomato) at increasing concentrations (0, 1, 10, and 100 µg/ml in solution). Psyllids exhibited a large and significant increase in mortality rate beginning at the lowest two concentrations, indicating that even very small quantities of these chemicals led to mortality. Feeding by nymphs on artificial diets containing synthetic compounds resulted in 100% mortality within 48 h, irrespective of compound. Further testing of ergot alkaloids to characterize the mode of action that leads to psyllid mortality is warranted.


Assuntos
Alcaloides de Claviceps , Hemípteros , Hypocreales , Solanum tuberosum , Animais , Ninfa
9.
Arch Virol ; 165(8): 1769-1776, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32440701

RESUMO

South Texas has experienced local transmission of Zika virus and of other mosquito-borne viruses such as chikungunya virus and dengue virus in the last decades. Using a mosquito surveillance program in the Lower Rio Grande Valley (LRGV) and San Antonio, TX, from 2016 to 2018, we detected the presence of an insect-specific virus, cell fusing agent virus (CFAV), in the Aedes aegypti mosquito population. We tested 6,326 females and 1,249 males from the LRGV and 659 females from San Antonio for CFAV by RT-PCR using specific primers. Infection rates varied from 0 to 261 per 1,000 mosquitoes in the LRGV and 115 to 208 per 1,000 in San Antonio depending on the month of collection. Infection rates per 1,000 individuals appeared higher in females collected from BG Sentinel 2 traps compared to Autocidal Gravid Ovitraps, but the ratio of the percentage of infected pools did not differ by trap type. The natural viral load in individual males ranged from 1.25 x 102 to 5.50 x 106 RNA copies and in unfed females from 5.42 x 103 to 8.70 x 106 RNA copies. Gravid females were found to harbor fewer viral particles than males and unfed females.


Assuntos
Aedes/virologia , Flavivirus/genética , Animais , Feminino , Vírus de Insetos/genética , Masculino , Mosquitos Vetores/genética , RNA Viral/genética , Texas , Carga Viral/genética
10.
Sci Rep ; 10(1): 6803, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321946

RESUMO

Aedes aegypti is the main vector of arboviral diseases such as dengue, chikungunya and Zika. A key feature for disease transmission modeling and vector control planning is adult mosquito dispersal. We studied Ae aegypti adult dispersal by conducting a mark-capture study of naturally occurring Ae. aegypti from discarded containers found along a canal that divided two residential communities in Donna, Texas, USA. Stable isotopes were used to enrich containers with either 13C or 15N. Adult mosquitoes were collected outdoors in the yards of households throughout the communities with BG Sentinel 2 traps during a 12-week period. Marked mosquito pools with stable isotopes were used to estimate the mean distance travelled using three different approaches (Net, Strip or Circular) and the probability of detecting an isotopically marked adult at different distances from the larval habitat of origin. We consistently observed, using the three approaches that male (Net: 220 m, Strip: 255 m, Circular: 250 m) Ae. aegypti dispersed further in comparison to gravid (Net: 135 m, Strip: 176 m, Circular: 189 m) and unfed females (Net: 192 m, Strip: 213 m, Circular: 198 m). We also observed that marked male capture probability slightly increased with distance, while, for both unfed and gravid females, such probability decreased with distance. Using a unique study design documenting adult dispersal from natural larval habitat, our results suggest that Ae. aegypti adults disperse longer distances than previously reported. These results may help guide local vector control authorities in their fight against Ae. aegypti and the diseases it transmits, suggesting coverage of 200 m for the use of insecticides and innovative vector control tools.


Assuntos
Isótopos de Carbono/metabolismo , Ecossistema , Meio Ambiente , Controle de Mosquitos/métodos , Isótopos de Nitrogênio/metabolismo , Algoritmos , Animais , Febre de Chikungunya/prevenção & controle , Febre de Chikungunya/transmissão , Febre de Chikungunya/virologia , Dengue/prevenção & controle , Dengue/transmissão , Dengue/virologia , Feminino , Humanos , Inseticidas/farmacologia , Masculino , Modelos Teóricos , Controle de Mosquitos/instrumentação , Mosquitos Vetores/efeitos dos fármacos , Mosquitos Vetores/metabolismo , Mosquitos Vetores/virologia , Texas , Infecção por Zika virus/prevenção & controle , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia
11.
Viruses ; 12(4)2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316394

RESUMO

Mosquito-borne viruses are emerging or re-emerging globally, afflicting millions of people around the world. Aedes aegypti, the yellow fever mosquito, is the principal vector of dengue, Zika, and chikungunya viruses, and has well-established populations across tropical and subtropical urban areas of the Americas, including the southern United States. While intense arboviral epidemics have occurred in Mexico and further south in the Americas, local transmission in the United States has been minimal. Here, we study Ae. aegypti and Culex quinquefasciatus host feeding patterns and vertebrate host communities in residential environments of South Texas to identify host-utilization relative to availability. Only 31% of Ae. aegypti blood meals were derived from humans, while 50% were from dogs and 19% from other wild and domestic animals. In Cx. quinquefasciatus, 67% of blood meals were derived from chicken, 22% came from dogs, 9% from various wild avian species, and 2% from other mammals including one human, one cat, and one pig. We developed a model for the reproductive number, R0, for Zika virus (ZIKV) in South Texas relative to northern Mexico using human disease data from Tamaulipas, Mexico. We show that ZIKV R0 in South Texas communities could be greater than one if the risk of human exposure to Ae. aegypti bites in these communities is at least 60% that of Northern Mexico communities. The high utilization of non-human vertebrates and low risk of human exposure in South Texas diminishes the outbreak potential for human-amplified urban arboviruses transmitted by Ae. aegypti.


Assuntos
Aedes/virologia , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia , Zika virus/fisiologia , Aedes/classificação , Animais , Geografia Médica , Especificidade de Hospedeiro , Interações Hospedeiro-Patógeno , Humanos , Modelos Teóricos , Texas/epidemiologia , Zoonoses Virais/epidemiologia , Zoonoses Virais/transmissão , Zoonoses Virais/virologia , Infecção por Zika virus/epidemiologia
12.
J Med Entomol ; 57(4): 1111-1119, 2020 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-32043525

RESUMO

Effective mosquito surveillance and management depend on a thorough understanding of the biology and feeding patterns unique to species and sex. Given that a propensity to sugar feed is necessary for some mosquito surveillance and newer control strategies, we sought to document the amount of total sugar in wild Aedes aegypti (L.) and Culex quinquefasciatus (Say) captured from five different locations in the Lower Rio Grande Valley (LRGV) of South Texas over 2 yr. We used Biogents Sentinel 2 (BGS2) traps in year 1 and aspirators, BGS2, and CDC resting traps in years 2 and 3 to collect adult mosquitoes. The hot anthrone test was used to quantify total sugar content in each mosquito. Additionally, the cold and hot anthrone tests were used to distinguish fructose content from total sugars for mosquitoes captured in 2019. Overall, Ae. aegypti females had significantly lower total sugar content than Ae. aegypti males as well as both sexes of Cx. quinquefasciatus. However, the percentage of Ae. aegypti positive for fructose consumption was four to eightfold higher than Ae. aegypti previously reported in other regions. The difference between locations was significant for males of both species, but not for females. Seasonality and trapping method also revealed significant differences in sugar content of captured mosquitoes. Our results reinforce that sugar feeding in female Ae. aegypti is less than Cx. quinquefasciatus, although not absent. This study provides necessary data to evaluate the potential effectiveness of sugar baits in surveillance and control of both Ae. aegypti and Cx. quinquefasciatus mosquitoes.


Assuntos
Aedes/química , Culex/química , Animais , Tamanho Corporal , Comportamento Alimentar , Feminino , Masculino , Estações do Ano , Açúcares , Texas
13.
Clin Pediatr (Phila) ; 59(2): 127-133, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31709814

RESUMO

Objectives. The primary objective is to determine the frequency of history findings associated with cardiac syncope. Second, to determine the frequency of abnormal electrocardiograms (EKG) in patients presenting with typical vasovagal syncope. Methods. Retrospective chart review from January 2006 to April 2017 of children aged 5 to 18 years presenting to the emergency department with a chief complaint of syncope. Target population was all patients with first episode of syncope and a documented EKG. Excluded patients were those with head trauma, drug intoxication, current pregnancy, seizure, and any endocrine problem. Patients with cardiac causes of syncope were identified by an abnormal EKG or echocardiogram. Specific history findings (past cardiac history, chest pain, palpitations, syncope with exercise, absence of prodrome with syncope) were compared with those with and without cardiac etiology of syncope. The possibility of missing a patient with cardiac cause of syncope based on specific history findings was identified. Results. Of the total 4115 visits of patients with chief complaints of syncope, 2293 patients (55.7%) met the inclusion criteria. Nine patients (0.39%) were identified with cardiac etiology of syncope. The remaining were determined to be of vasovagal origin. All patients with cardiac etiology of syncope were found to have one positive specific history findings. A total of 1972 patients were identified with absence of specific history findings; no patient had a cardiac etiology of syncope. Conclusions. This study identifies screening questions to identify cardiac syncope. Implementing these standard questions could potentially decrease resource utilization and time for evaluation as well as guide follow-up.


Assuntos
Saúde da Criança , Serviço Hospitalar de Emergência , Síncope/diagnóstico , Adolescente , Arritmias Cardíacas/diagnóstico , Dor no Peito/etiologia , Criança , Pré-Escolar , Eletrocardiografia , Feminino , Humanos , Masculino , Exame Físico , Estudos Retrospectivos , Síncope/complicações
14.
J Econ Entomol ; 113(2): 1018-1022, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-31778533

RESUMO

Tagosodes orizicolus (Muir) is the most important pest of rice in Latin America. Besides causing direct damage called hopperburn from feeding on and ovipositing in rice leaves, this insect pest also transmits rice hoja blanca virus (RHBV, Family Phenuiviridae, Genus Tenuivirus) in a persistent-propagative manner. This pathosystem can cause up to 100% yield loss in Latin American rice fields. T. orizicolus and RHBV symptoms were detected in Louisiana, Mississippi, and Florida rice fields in the 1950s, 1960s, and 1980s. However, neither has been detected in the United States since. Two outbreaks of T. orizicolus on ratoon rice occurred in the fall of 2015 and 2018 in counties southwest and south of Houston, TX. Insects were collected from ratoon rice fields by sweep net methods. Insects from the 2015 and 2018 outbreaks were tested individually and in pools of 10, respectively, for RHBV infection and the cytochrome oxidase 1 (CO1) gene from Delphacidae. No insects were positive for RHBV, however, all samples yielded amplicons for the CO1 gene. Furthermore, the CO1 gene from five 2015 individuals was sequenced and found to have a 100% identity to the Fer26_Argentina and 99.81% identity to the DEL074 Venezuela isolates of T. orizicolus. Five new sequences from 2015 individuals have now been deposited in GenBank. It is imperative to stay up to date on the potential invasion and establishment of this exotic pest of rice in Texas and other rice-growing regions of the United States through continued monitoring and research.


Assuntos
Hemípteros , Infecções , Oryza/virologia , Tenuivirus , Animais , Argentina , Florida , Louisiana , Mississippi , Texas
15.
J Med Entomol ; 57(2): 649-652, 2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-31751467

RESUMO

The use of stable isotope enrichment to mark mosquitoes has provided a tool to study the biology of vector species. In this study, we evaluated isotopic marking of Aedes aegypti (L.) (Diptera: Culicidae) in a laboratory setting. We determined the optimal dosage for marking adult Ae. aegypti mosquitoes with 13C and 15N. Additionally, Ae. aegypti mosquitoes were single and dually marked with 13C and 15N for up to 60 d postemergence without changes to adult body size or transgenerational marking. This report adds to the growing literature that explores the use of alternative marking methods for ecological and vector biology studies.


Assuntos
Aedes , Isótopos de Carbono/análise , Entomologia/métodos , Controle de Mosquitos/métodos , Mosquitos Vetores , Isótopos de Nitrogênio/análise , Animais , Ecologia/métodos , Feminino , Masculino
16.
J Am Mosq Control Assoc ; 35(3): 233-237, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31647710

RESUMO

South Texas is recognized as a potential area for the emergence and re-emergence of mosquito-borne diseases due to recent circulation of Zika, chikungunya, and dengue viruses. During 2017, high Aedes aegypti abundance found in the city of Brownsville, TX, in combination with the previous year's local transmission of Zika virus, triggered the activation of the Texas Department of State Health Services Emergency Mosquito Control Contingency Contract. A contract with the Clarke Environmental and Mosquito Control was a response to control Ae. aegypti, using a ground-based wide-area larvicide spray (WALS™) containing Bacillus thuringiensis israelensis. The WALS application was evaluated through a field-based bioassay and by comparing surveillance data pre- and post-WALS application. The WALS application bioassay demonstrated that the larvicide was effective up to 60 m into the target properties. Additionally, the number of Ae. aegypti captured in traps decreased in the WALS intervention areas compared with the untreated control areas, with an estimated 29% control.


Assuntos
Aedes , Bacillus thuringiensis/química , Controle de Mosquitos/métodos , Aedes/efeitos dos fármacos , Aedes/crescimento & desenvolvimento , Animais , Larva/efeitos dos fármacos , Texas
17.
J Virol ; 93(21)2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31413126

RESUMO

The plant-pathogenic virus tomato spotted wilt virus (TSWV) encodes a structural glycoprotein (GN) that, like with other bunyavirus/vector interactions, serves a role in viral attachment and possibly in entry into arthropod vector host cells. It is well documented that Frankliniella occidentalis is one of nine competent thrips vectors of TSWV transmission to plant hosts. However, the insect molecules that interact with viral proteins, such as GN, during infection and dissemination in thrips vector tissues are unknown. The goals of this project were to identify TSWV-interacting proteins (TIPs) that interact directly with TSWV GN and to localize the expression of these proteins in relation to virus in thrips tissues of principal importance along the route of dissemination. We report here the identification of six TIPs from first-instar larvae (L1), the most acquisition-efficient developmental stage of the thrips vector. Sequence analyses of these TIPs revealed homology to proteins associated with the infection cycle of other vector-borne viruses. Immunolocalization of the TIPs in L1 revealed robust expression in the midgut and salivary glands of F. occidentalis, the tissues most important during virus infection, replication, and plant inoculation. The TIPs and GN interactions were validated using protein-protein interaction assays. Two of the thrips proteins, endocuticle structural glycoprotein and cyclophilin, were found to be consistent interactors with GN These newly discovered thrips protein-GN interactions are important for a better understanding of the transmission mechanism of persistent propagative plant viruses by their vectors, as well as for developing new strategies of insect pest management and virus resistance in plants.IMPORTANCE Thrips-transmitted viruses cause devastating losses to numerous food crops worldwide. For negative-sense RNA viruses that infect plants, the arthropod serves as a host as well by supporting virus replication in specific tissues and organs of the vector. The goal of this work was to identify thrips proteins that bind directly to the viral attachment protein and thus may play a role in the infection cycle in the insect. Using the model plant bunyavirus tomato spotted wilt virus (TSWV), and the most efficient thrips vector, we identified and validated six TSWV-interacting proteins from Frankliniella occidentalis first-instar larvae. Two proteins, an endocuticle structural glycoprotein and cyclophilin, were able to interact directly with the TSWV attachment protein, GN, in insect cells. The TSWV GN-interacting proteins provide new targets for disrupting the viral disease cycle in the arthropod vector and could be putative determinants of vector competence.


Assuntos
Proteínas de Insetos/metabolismo , Insetos Vetores/metabolismo , Tisanópteros/metabolismo , Tospovirus/metabolismo , Proteínas Estruturais Virais/metabolismo , Animais , Proteínas de Insetos/genética , Insetos Vetores/classificação , Insetos Vetores/genética , Larva/metabolismo , Filogenia , Doenças das Plantas/virologia , Plantas Geneticamente Modificadas , Ligação Proteica , Células Sf9 , Tisanópteros/classificação , Tisanópteros/genética , Tospovirus/genética , Tospovirus/fisiologia , Proteínas Estruturais Virais/genética
18.
Acta Trop ; 192: 129-137, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30763563

RESUMO

The yellow fever mosquito, Aedes aegypti, has facilitated the re-emergence of dengue virus (DENV) and emergence of chikungunya virus (CHIKV) and Zika virus (ZIKV) in the Americas and the Caribbean. The recent transmission of these arboviruses in the continental United States has been limited, to date, to South Florida and South Texas despite Ae. aegypti occurring over a much larger geographical region within the country. The main goal of our study was to provide the first long term longitudinal study of Ae. aegypti and enhance the knowledge about the indoor and outdoor relative abundance of Ae. aegypti as a proxy for mosquito-human contact in South Texas, a region of the United States that is at high risk for mosquito-borne virus transmission. Here, the relative abundance of indoors and outdoors mosquitoes of households in eight different communities was described. Surveillance was done weekly from September 2016 to April 2018 using the CDC Autocidal Gravid Ovitraps in low- and middle-income communities. A total of 69 houses were included in this survey among which 36 were in the low-income communities (n = 11 for Donna, n = 15 for Progresso, n = 5 for Mesquite, n = 5 for Chapa) and 33 in middle-income communities (n = 9 for La Feria, n = 8 for Weslaco, n = 11 for McAllen, and n = 5 for Rio Rico). Overall, Ae. aegypti was the dominant species (59.2% of collections, n = 7255) followed by Culex spp. mosquitoes (27.3% of collections, n = 3350). Furthermore, we demonstrated for Ae. aegypti that 1) outdoor relative abundance was higher compared to indoor relative abundance, 2) low-income communities were associated with an increase in mosquito relative abundance indoors when compared to middle-income communities, 3) no difference was observed in the number of mosquitoes collected outdoors between low-income and middle-income communities, and 4) warmer months were positively correlated with outdoor relative abundance whereas no seasonality was observed in the relative abundance of mosquitoes indoors. Additionally, Ae. aegypti mosquitoes collected in South Texas were tested using a specific ZIKV/CHIKV multiplex real-time PCR assay, however, none of the mosquitoes tested positive. Our data highlights the occurrence of mosquitoes indoors in the continental United States and that adults are collected nearly every week of the calendar year. These mosquito data, obtained concurrently with local ZIKV transmission of 10 locally acquired cases in nearby communities, represent a baseline for future studies in the Lower Rio Grande Valley (LRGV) including vector control interventions relying on the oviposition behavior to reduce mosquito populations and pathogen transmission.


Assuntos
Aedes/virologia , Febre de Chikungunya/transmissão , Culex/virologia , Dengue/transmissão , Mosquitos Vetores/virologia , Febre Amarela/transmissão , Infecção por Zika virus/transmissão , Animais , Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Dengue/virologia , Vírus da Dengue/isolamento & purificação , Características da Família , Feminino , Humanos , Estudos Longitudinais , Texas , Estados Unidos , Febre Amarela/virologia , Zika virus/isolamento & purificação
19.
PLoS One ; 13(9): e0201506, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30204748

RESUMO

Plant species in the family Solanaceae are the usual hosts of potato psyllid, Bactericera cockerelli (Sulc) (Hemiptera: Psylloidea: Triozidae). However, the psyllid has also been shown to develop on some species of Convolvulaceae (bindweeds and morning glories). Developmental success on Convolvulaceae is surprising given the rarity of psyllid species worldwide associated with this plant family. We assayed 14 species of Convolvulaceae across four genera (Convolvulus, Calystegia, Ipomoea, Turbina) to identify species that allow development of potato psyllid. Two populations of psyllids were assayed (Texas, Washington). The Texas population overlaps extensively with native Convolvulaceae, whereas Washington State is noticeably lacking in Convolvulaceae. Results of assays were overlain on a phylogenetic analysis of plant species to examine whether Convolvulaceae distantly related to the typical host (potato) were less likely to allow development than species of Convolvulaceae more closely related. Survival was independent of psyllid population and location of the plant species on our phylogenetic tree. We then examined whether presence of a fungal symbiont of Convolvulaceae (Periglandula spp.) affected psyllid survival. These fungi associate with Convolvulaceae and produce a class of mycotoxins (ergot alkaloids) that may confer protection against plant-feeding arthropods. Periglandula was found in 11 of our 14 species, including in two genera (Convolvulus, Calystegia) not previously known to host the symbiont. Of these 11 species, leaf tissues from five contained large quantities of two classes of ergot alkaloids (clavines, amides of lysergic acid) when evaluated by LC-MS/MS. All five species also harbored Periglandula. No ergot alkaloids were detected in species free of the fungal symbiont. Potato psyllid rapidly died on the five species that harbored Periglandula and contained ergot alkaloids, but survived to adulthood on seven of the nine species in which ergot alkaloids were not detected. These results support the hypothesis that a plant-fungus symbiotic relationship affects the suitability of certain Convolvulaceae to potato psyllid.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Hemípteros/crescimento & desenvolvimento , Solanum tuberosum , Simbiose/fisiologia , Animais , Filogenia , Solanum tuberosum/microbiologia , Solanum tuberosum/parasitologia
20.
Sensors (Basel) ; 18(1)2018 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-29315219

RESUMO

Water quality monitoring through remote sensing with UAVs is best conducted using multispectral sensors; however, these sensors are expensive. We aimed to predict multispectral bands from a low-cost sensor (R, G, B bands) using artificial neural networks (ANN). We studied a lake located on the campus of Unisinos University, Brazil, using a low-cost sensor mounted on a UAV. Simultaneously, we collected water samples during the UAV flight to determine total suspended solids (TSS) and dissolved organic matter (DOM). We correlated the three bands predicted with TSS and DOM. The results show that the ANN validation process predicted the three bands of the multispectral sensor using the three bands of the low-cost sensor with a low average error of 19%. The correlations with TSS and DOM resulted in R² values of greater than 0.60, consistent with literature values.

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