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1.
Molecules ; 26(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34641444

RESUMO

The family Tephritidae (Diptera) includes species that are highly invasive and harmful to crops. Due to globalization, international trade, and human displacement, their spread is continuously increasing. Unfortunately, the control of tephritid flies is still closely linked to the use of synthetic insecticides, which are responsible for detrimental effects on the environment and human health. Recently, research is looking for alternative and more eco-friendly tools to be adopted in Integrated Pest Management (IPM) programs. In this regard, essential oils (EOs) and their main compounds represent a promising alternative to chemical insecticides. EOs are made up of phytoconstituents formed from the secondary metabolism of many plants and can act as attractants or toxics, depending on the dose. Because of this unique characteristic, EOs and their main constituents are promising tools that can be used both in Sterile Insect Technique (SIT) programs and in the "lure and kill" technique, exploiting the attractiveness of the product in the former case and its toxicity in the latter. In this article, current knowledge on the biological and behavioral effects of EOs and their main constituents on tephritid fruit flies is reviewed, mainly focusing on species belonging to the Anastrepha, Bactrocera, Ceratitis, and Zeugodacus genera. The mechanisms of action of EOs, their real-world applications, and challenges related to their use in IPM are critically discussed.


Assuntos
Controle de Insetos/métodos , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Tephritidae/efeitos dos fármacos , Animais
2.
Microb Ecol ; 73(3): 677-684, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27687872

RESUMO

The occurrence of interaction between insects and fungi is interesting from an ecological point of view, particularly when these interactions involve insect pests and plant pathogens within an agroecosystem. In this study, we aimed to perform an accurate analysis on the fungal microbiota associated to Bactrocera oleae (Rossi) through a metabarcoding approach based on 454 pyrosequencing. From this analysis, we retrieved 43,549 reads that clustered into 128 operational taxonomic units (OTUs), of which 29 resulted in the "core" associate fungi of B. oleae. This fungal community was mainly represented by sooty mould fungi, such as Cladosporium spp., Alternaria spp. and Aureobasidium spp., by plant pathogens like Colletotrichum spp. and Pseudocercospora spp., along with several other less abundant taxa whose ecology is unclear in most of the cases. Our findings lead to new insights into the microbial ecology of this specific ecological niche, enabling the understanding of a complex network of interactions within the olive agroecosystem.


Assuntos
Alternaria/classificação , Ascomicetos/classificação , Cladosporium/classificação , Colletotrichum/classificação , Código de Barras de DNA Taxonômico/métodos , Micobioma/genética , Tephritidae/microbiologia , Alternaria/genética , Alternaria/isolamento & purificação , Animais , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Sequência de Bases , Cladosporium/genética , Cladosporium/isolamento & purificação , Colletotrichum/genética , Colletotrichum/isolamento & purificação , DNA Intergênico/genética , Sequenciamento de Nucleotídeos em Larga Escala , Olea , Análise de Sequência de DNA
3.
J Sci Food Agric ; 95(12): 2473-81, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25355375

RESUMO

BACKGROUND: Light and water are major factors in fruit development and quality. In this study, the effect of water and light in Olea europaea trees on volatile organic compounds (VOCs) in olive oil was studied over 2 years. Mature fruits were harvested from three zones of the canopy with different light exposure (64%, 42% and 30% of incident light) of trees subjected to full, deficit or complementary irrigation. VOCs were determined by SPME GC-MS and analysed by principal component analysis followed by discriminant analysis to partition treatment effects. RESULTS: Fruit fresh weight and mesocarp oil content decreased in zones where intercepted light was less. Low light levels significantly slowed down fruit maturation, whereas conditions of water deficit accelerated the maturation process. The presence of cyclosativene and α-muurulene was associated with water deficit, nonanal, valencene with full irrigation; α-muurulene, (E)-2-hexanal were related to low light conditions, while trans-ß-ocimene, α-copaene, (Z)-2-penten-1-ol, hexanal and nonanal to well exposed zones. The year strongly affected the VOC profile of olive oil. CONCLUSION: This is the first report on qualitative changes in VOCs induced by light environment and/or water status. This information is valuable to better understand the role of environmental factors on the sensory quality of virgin olive oil.


Assuntos
Olea , Azeite de Oliva/química , Óleos de Plantas/química , Compostos Orgânicos Voláteis/química , Qualidade dos Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Olea/química , Luz Solar , Água
4.
Naturwissenschaften ; 101(9): 753-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25008388

RESUMO

Animals rely on associative learning for a wide range of purposes, including danger avoidance. This has been demonstrated for several insects, including cockroaches, mosquitoes, drosophilid flies, paper wasps, stingless bees, bumblebees and honeybees, but less is known for parasitic wasps. We tested the ability of Psyttalia concolor (Hymenoptera: Braconidae) females to associate different dosages of two innately attractive host-induced plant volatiles (HIPVs), ethyl octanoate and decanal, with danger (electric shocks). We conducted an associative treatment involving odours and shocks and two non-associative controls involving shocks but not odours and odours but not shocks. In shock-only and odour-only trained wasps, females preferred on HIPV-treated than on blank discs. In associative-trained wasps, however, P. concolor's innate positive chemotaxis for HIPVs was nullified (lowest HIPV dosage tested) or reversed (highest HIPV dosage tested). This is the first report of associative learning of olfactory cues for danger avoidance in parasitic wasps, showing that the effects of learning can override innate positive chemotaxes.


Assuntos
Aprendizagem da Esquiva/fisiologia , Quimiotaxia/fisiologia , Interações Hospedeiro-Parasita/fisiologia , Vespas/fisiologia , Animais , Sinais (Psicologia) , Eletricidade , Feminino , Odorantes , Plantas/química
5.
J Econ Entomol ; 107(6): 2005-22, 2014 12.
Artigo em Inglês | MEDLINE | ID: mdl-26470064

RESUMO

Aphidius colemani Viereck (Hymenoptera: Braconidae: Aphidiinae) is a pan-tropical, broadly oligophagous, solitary endoparasitoid of many aphids of economic importance. Here, we review current knowledge about this important biological control agent, with a special focus on the physical and chemical cues triggering mating and host-seeking behavior. First, we focus on female-borne olfactory cues evoking courtship in A. colemani males, as well as on the relationship between male mating performance and quality of the host species. Second, we examine how A. colemani females forage for hosts and assess their suitability, using both aphid-borne kairomones and host-related physical cues. Third, we review A. colemani-based biological control approaches, outlining how knowledge of its reproductive behavioral ecology may enhance biological control of aphid pests. Concepts for future biocontrol programs are outlined, including 1) use of sex attractant dispensers for monitoring, 2) mass-rearing optimization based on knowledge of mate-finding strategies and sexually selected traits, 3) deployment of aphid-borne foraging kairomones as field lures to attract parasitoids into infested agro-ecosystems, 4) use of sensitization or associative learning practices to optimize efficacy of mass-reared wasps.


Assuntos
Afídeos/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Comportamento de Busca por Hospedeiro/fisiologia , Controle Biológico de Vetores , Comportamento Sexual Animal/fisiologia , Vespas/fisiologia , Animais , Sinais (Psicologia) , Olfato , Vespas/parasitologia
6.
Insects ; 15(7)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39057209

RESUMO

Spodoptera littoralis, commonly known as the Egyptian or African cotton leafworm, is a significant agricultural threat. It is widely distributed in Africa, Mediterranean Europe, and Middle Eastern countries. This polyphagous pest infests numerous crop plants across 44 families, including cotton, soybeans, alfalfa, sweet potato, pepper, eggplant, tomato, maize, lettuce, strawberry, wheat, and hibiscus. The damage caused by S. littoralis on different plant organs, such as young leaves, shoots, stalks, bolls, buds, and fruits, often determines substantial product losses. Current control strategies predominantly rely on synthetic insecticides, which, despite their efficacy, have notable drawbacks, including insecticide resistance, environmental contamination, consumer concerns, and adverse effects on non-target organisms and beneficial insects. In response to these challenges, in this study, we developed and evaluated a garlic EO-based nanoemulsion with a high EO concentration (15%) and low surfactant content to mitigate the possible negative impact on plants and to enhance efficacy against S. littoralis larvae. Laboratory bioassays demonstrated promising larvicidal activity and reduced larval feeding, although some phytotoxicity symptoms were observed. This study underscores the potential of botanical insecticides as sustainable alternatives to synthetic chemicals, emphasizing the importance of balancing efficacy with environmental and ecological considerations in pest management strategies.

7.
Acta Trop ; 239: 106832, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36642256

RESUMO

Invasive mosquitoes (Diptera: Culicidae) play a key role in the spread of a number of mosquito-borne diseases worldwide. Anthropogenic changes play a significant role in affecting their distribution. Invasive mosquitoes usually take advantage from biotic homogenization and biodiversity reduction, therefore expanding in their distribution range and abundance. In Europe, climate warming and increasing urbanization are boosting the spread of several mosquito species of high public health importance. The present article contains a literature review focused on the biology and ecology of Aedes albopictus, Ae. aegypti, Ae. japonicus japonicus, Ae. koreicus, Ae. atropalpus and Ae. triseriatus, outlining their distribution and public health relevance in Europe. Bioecology insights were tightly connected with vector surveillance and control programs targeting these species. In the final section, a research agenda aiming for the effective and sustainable monitoring and control of invasive mosquitoes in the framework of Integrated Vector Management and One Health is presented. The WHO Vector Control Advisory Group recommends priority should be given to vector control tools with proven epidemiological impact.


Assuntos
Aedes , Mosquitos Vetores , Animais , Europa (Continente)/epidemiologia , Clima , Saúde Pública , Espécies Introduzidas
8.
Insects ; 13(12)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36555059

RESUMO

Due to its high polyphagy, Aphis gossypii is considered a key pest of many crops, and it can feed on hundreds of plant species belonging to the families Cucurbitaceae, Malvaceae, Solanaceae, Rutaceae, and Asteraceae. The control of this pest mainly relies on synthetic insecticides whose adverse effects on the environment and human health are encouraging researchers to explore innovative, alternative solutions. In this scenario, essential oils (EOs) could play a key role in the development of ecofriendly pesticides. In this study, the development of a citrus peel EO-based nano-formulation and its biological activity against A. gossypii both in the laboratory and field were described and evaluated. The phytotoxicity towards citrus plants was also assessed. The developed nano-insecticide highlighted good aphicidal activity both in the laboratory and field trials, even at moderate EO concentrations. However, the highest tested concentrations (4 and 6% of active ingredient) revealed phytotoxic effects on the photosynthetic apparatus; the side effects need to be carefully accounted for to successfully apply this control tool in field conditions.

9.
J Int Neuropsychol Soc ; 17(6): 1158-62, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22014082

RESUMO

The present study investigated memory for intention in individuals with Parkinson's disease (PD) who were newly diagnosed and not yet treated to avoid the effect of therapy as a potential confounding variable. A comprehensive neuropsychological battery and an event-based prospective memory task were administered to 41 subjects with de novo PD and 40 control subjects. Separate scores were computed for correct execution of intended action (prospective component) and recall of intention (retrospective component). PD patients performed marginally worse (p = .053) than controls on the prospective component of the task. On the other hand, the performance of the two groups was comparable for the retrospective component. Neuropsychological findings revealed lower performance of the PD group in episodic memory and in some measures of executive functions. These results suggested a subtle prospective memory dysfunction present at the initial stage of PD, which may be related to disruption of fronto-striatal circuitry.


Assuntos
Intenção , Transtornos da Memória/etiologia , Memória Episódica , Doença de Parkinson/complicações , Idoso , Análise de Variância , Feminino , Humanos , Masculino , Transtornos da Memória/diagnóstico , Rememoração Mental/fisiologia , Testes Neuropsicológicos
10.
N Z Med J ; 134(1542): 96-108, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34531588

RESUMO

Chimeric antigen receptor (CAR) T-cells are a personalised cell and gene therapy for cancer that are becoming an international standard of care for some refractory B-cell leukaemias, non-Hodgkin lymphomas and myeloma. A single CAR T-cell administration can result in durable complete response for some recipients. Domestic CAR T-cell manufacturing capability was established for Aotearoa New Zealand's first CAR T-cell trial (ENABLE, ClinicalTrials.gov NCT04049513). This article outlines CAR T-cell manufacturing and logistical considerations, with a focus on New Zealand's environment for this personalised cell and gene therapy. We discuss Maori engagement in CAR T-cell trial and clinical service design, and propose enhancing Maori guardianship (kaitiakitanga) over cells and genetic material through on-shore manufacture. Strategies to safely deliver CAR T-cells within New Zealand's healthcare system are outlined. Finally, we discuss challenges to, and opportunities for, widening CAR T-cell availability and assuring equity of access. Based on our experience, we consider Aotearoa New Zealand to be in an excellent position to develop and implement investigational and commercial CAR T-cell therapies in the future.


Assuntos
Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Linfoma de Células B/terapia , Linfoma não Hodgkin/terapia , Receptores de Antígenos Quiméricos/uso terapêutico , Linfócitos T/transplante , Adolescente , Adulto , Idoso , Feminino , Equidade em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Havaiano Nativo ou Outro Ilhéu do Pacífico , Recidiva Local de Neoplasia , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/imunologia , Nova Zelândia , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos Quiméricos/imunologia , Indução de Remissão , Linfócitos T/imunologia , Adulto Jovem
11.
Insects ; 12(2)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562256

RESUMO

The development of biologically based approaches for stored product pest control is needed to reduce chemical inputs. Bioassays were performed to investigate host habitat location in the trophic interaction durum wheat/Rhyzopertha dominica/Theocolax elegans. GC-MS analyses were carried out to identify some chemical compounds produced by the host-related substrates. Choice and no-choice experiments demonstrated that female parasitoids were poorly attracted to intact kernels with respect to the infested substrates. Furthermore, T. elegans females performed longer residence time on infested wheat, and they generally displayed a short-term like fidelity for this cue, remaining on it during the whole observation. Infested wheat emitted one chemical (fenchone), which is possibly linked to host larvae presence, while the feces produced by host larvae emitted some other characteristic compounds. Results demonstrated that the presence of host larvae is a key factor for T. elegans host habitat location, considering that the attractiveness of the undamaged wheat is irrelevant. Furthermore, parasitoid females tended to stay on attractive cues, limiting the risk of contamination of other commodities. Biological control tools may be useful to improve the efficiency of pest management programs, but their application should be carefully evaluated.

12.
Sci Rep ; 10(1): 1666, 2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-32015351

RESUMO

Plant nutritional quality and chemical characteristics may affect the fitness of phytophagous insects. Here, the olfactory preferences of Bactrocera oleae (Rossi) females toward olives with different maturation and infestation status were evaluated in three cultivars: Ottobratica, Roggianella and Sinopolese. Volatile profiles from olives were identified by SPME/GC-MS. Choice tests were performed to determine the responses of B. oleae adult females toward fruits and pure chemicals linked to infestation degree. Cultivar was the main source of variability explaining the differences recorded in volatile emissions. Moreover, three VOCs [ß-myrcene, limonene and (E)-ß-ocimene] were associated to infestation status across all olive varieties. In choice-tests, B. oleae females always preferred the olfactory cues from low-infested over high-infested fruits. Therefore, choice-tests using synthetic VOCs, emitted in greater amount by high-infested fruit, were arranged in order to identify putative B. oleae kairomones. While females were indifferent to ß-myrcene, the highest dosages of limonene and (E)-ß-ocimene were unfavoured by the tested flies, which preferentially moved toward the empty arm of the Y-tube. Furthermore, females preferred the lowest concentration of ß-ocimene compared to the highest one. These results supported our hypothesis that fruit VOCs may serve as kairomones for female flies.


Assuntos
Olea/química , Olea/parasitologia , Tephritidae/fisiologia , Monoterpenos Acíclicos/química , Alcenos/química , Animais , Quimiotaxia/fisiologia , Feminino , Preferências Alimentares/fisiologia , Frutas/química , Frutas/parasitologia , Cromatografia Gasosa-Espectrometria de Massas , Especificidade de Hospedeiro , Limoneno/química , Odorantes/análise , Oviposição/fisiologia , Feromônios/química , Feromônios/fisiologia , Olfato/fisiologia , Compostos Orgânicos Voláteis/química
13.
BMJ Open ; 10(2): e034629, 2020 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-32041862

RESUMO

INTRODUCTION: Autologous T-cells transduced to express a chimeric antigen receptor (CAR) directed against CD19 elicit high response rates in relapsed or refractory (r/r) B-cell non-Hodgkin lymphoma (B-NHL). However, r/r B-NHL remissions are durable in fewer than half of recipients of second-generation CAR T-cells. Third-generation (3G) CARs employ two costimulatory domains, resulting in improved CAR T-cell efficacy in vitro and in animal models in vivo. This investigator-initiated, phase I dose escalation trial, termed ENABLE, will investigate the safety and preliminary efficacy of WZTL-002, comprising autologous T-cells expressing a 3G anti-CD19 CAR incorporating the intracellular signalling domains of CD28 and Toll-like receptor 2 (TLR2) for the treatment of r/r B-NHL. METHODS AND ANALYSIS: Eligible participants will be adults with r/r B-NHL including diffuse large B-cell lymphoma and its variants, follicular lymphoma, transformed follicular lymphoma and mantle cell lymphoma. Participants must have satisfactory organ function, and lack other curative options. Autologous T-cells will be obtained by leukapheresis. Following WZTL-002 manufacture and product release, participants will receive lymphodepleting chemotherapy comprising intravenous fludarabine and cyclophosphamide. A single dose of WZTL-002 will be administered intravenously 2 days later. Targeted assessments for cytokine release syndrome and immune cell effector-associated neurotoxicity syndrome, graded by the American Society Transplantation and Cellular Therapy criteria, will be made. A modified 3+3 dose escalation scheme is planned starting at 5×104 CAR T-cells/kg with a maximum dose of 1×106 CAR T-cells/kg. The primary outcome of this trial is safety of WZTL-002. Secondary outcomes include feasibility of WZTL-002 manufacture and preliminary measures of efficacy. ETHICS AND DISSEMINATION: Ethical approval for the study was granted by the New Zealand Health and Disability Ethics Committee (reference 19/STH/69) on 23 June 2019 for Protocol V.1.2. Trial results will be reported in a peer-reviewed journal, and results presented at scientific conferences or meetings. TRIAL REGISTRATION NUMBER: NCT04049513.


Assuntos
Imunoterapia Adotiva , Linfoma de Células B/terapia , Receptores de Antígenos Quiméricos , Adolescente , Adulto , Idoso , Antígenos CD28/imunologia , Ensaios Clínicos Fase I como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Nova Zelândia , Linfócitos T/imunologia , Receptor 2 Toll-Like/imunologia , Adulto Jovem
14.
J Neurosci ; 27(41): 11037-46, 2007 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-17928445

RESUMO

Familial epilepsies are often caused by mutations of voltage-gated Na+ channels, but correlation genotype-phenotype is not yet clear. In particular, the cause of phenotypic variability observed in some epileptic families is unclear. We studied Na(v)1.1 (SCN1A) Na+ channel alpha subunit M1841T mutation, identified in a family characterized by a particularly large phenotypic spectrum. The mutant is a loss of function because when expressed alone, the current was no greater than background. Function was restored by incubation at temperature <30 degrees C, showing that the mutant is trafficking defective, thus far the first case among neuronal Na+ channels. Importantly, also molecular interactions with modulatory proteins or drugs were able to rescue the mutant. Protein-protein interactions may modulate the effect of the mutation in vivo and thus phenotype; variability in their strength may be one of the causes of phenotypic variability in familial epilepsy. Interacting drugs may be used to rescue the mutant in vivo.


Assuntos
Substituição de Aminoácidos/genética , Epilepsia/genética , Epilepsia/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Canais de Sódio/genética , Canais de Sódio/metabolismo , Variação Genética/genética , Humanos , Canal de Sódio Disparado por Voltagem NAV1.1 , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Transporte Proteico/genética
15.
Sci Rep ; 8(1): 2052, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29391446

RESUMO

Olfaction is a pivotal sense for insects and granivorous pests may exploit grain volatiles for food selection. Tribolium confusum, is a secondary pest of stored cereals that benefits from primary pests' infestation, as other secondary feeders, triggering competition. This study aimed to evaluate the preferences of T. confusum females toward different-infested paddy rice, highlighting the impact of intra- and interspecific competition. Tribolium confusum showed positive chemotaxis toward rice infested by larvae of a primary pest (Sitophilus zeamais), but not for grain attacked by adults alone. Furthermore, kernels concurrently infested by a primary (S. zeamais) and a secondary pest (T. confusum or Cryptolestes ferrugineus) were evaluated in Y-tube bioassays, highlighting that both food-sources were innately attractive for T. confusum females. Moreover, females positively oriented toward rice infested by conspecifics, while they avoided grain infested by C. ferrugineus, averting an extremely competitive habitat. Behavioural responses of T. confusum females and volatile emissions of different-infested rice highlighted the occurrence of plant-mediated interactions among insects from the same trophic guild. Seventy volatiles were identified and significant differences among the tested food-sources were recorded, emphasizing the presence of 6 putative attractants and 6 repellents, which may be useful biocontrol tools.


Assuntos
Biodiversidade , Besouros/fisiologia , Grão Comestível/parasitologia , Óleos Voláteis/farmacologia , Animais , Quimiotaxia , Besouros/efeitos dos fármacos , Besouros/patogenicidade , Grão Comestível/química , Feminino , Especificidade de Hospedeiro , Oryza/química , Oryza/parasitologia , Olfato
16.
Saudi J Biol Sci ; 24(5): 1045-1050, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28663702

RESUMO

Honeybees are critically important for the environment and to the economy. However, there are in substantial decline worldwide, leading to serious threat to the stability and yield of food crops. Beekeeping is of pivotal importance, combining the wide economical aspect of honey production and the important ecological services provided by honeybees. In this scenario, the prompt identification of beekeeping areas is strategic, since it maximised productivity and lowered the risks of colony losses. Fuzzy logic is an ideal approach for problem-solving tasks, as it is specifically designed to manage problems with a high degree of uncertainty. This research tested a novel GIS-based approach to assess beekeeping suitability of lands located in Calabria (Southern Italy), without relying to Analytic Hierarchy Process - Multiple Criteria Decision Making (AHP-MCDM), thus avoiding the constraints due to the technique and decision makers' influences. Furthermore, the data used here were completely retrieved from open access sources, highlighting that our approach is characterized by low costs and can be easily reproduced for a wide arrays of geographical contexts. Notably, the results obtained by our experiments were validated by the actual beekeeping reality. Besides beekeeping, the use of this system could not only be applied in beekeeping land suitability evaluations, but may be successfully extended to other types of land suitability evaluations.

17.
J Econ Entomol ; 109(6): 2272-2280, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27616766

RESUMO

Parasitic wasps can learn cues that alter their behavioral responses and increase their fitness, such as those that improve host location efficiency. Psyttalia concolor (Szépligeti) (Hymenoptera: Braconidae) is a koinobiont endoparasitoid of 14 economically important tephritid species, including the olive fruit fly, Bactrocera oleae (Rossi) (Diptera: Tephritidae). In this research, we investigated the nature of olfactory cues mediating this tritrophic interaction. First, we identified the chemical stimuli emanating from uninfested and B. oleae-infested olive fruits via solid phase microextraction and gas chromatography-mass spectrometry analyses and identified >70 volatile organic compounds (VOCs). Two of these were increased by B. oleae infestation, (E)-ß-ocimene and 2-methyl-6-methylene-1,7-octadien-3-one, and four were decreased, α-pinene, ß-pine ne, limonene, and ß-elemene. Innate positive chemotaxis of mated P. concolor females toward these VOCs was then tested in olfactometer assays. Females were attracted only by (E)-ß-ocimene, at both tested dosages, indicating an intrinsic response to this compound as a short-range attractant. Next, we tested whether mated P. concolor females could learn to respond to innately unattractive VOCs if they were first presented with a food reward. Two nonassociative controls were conducted, i.e., "odor only" and "reward only." Following training, females showed positive chemotaxis toward these VOCs in all tested combinations, with the exception of limonene, a VOC commonly produced by flowers. Control females showed no significant preferences, indicating that positive associative learning had occurred. These results clarify how learned cues can fine-tune innate responses to B. oleae-induced VOCs in this generalist parasitoid of tephritid flies.


Assuntos
Quimiotaxia , Cadeia Alimentar , Olea/metabolismo , Tephritidae/fisiologia , Compostos Orgânicos Voláteis/metabolismo , Vespas/fisiologia , Animais , Feminino , Frutas/crescimento & desenvolvimento , Frutas/parasitologia , Frutas/fisiologia , Cromatografia Gasosa-Espectrometria de Massas , Larva/crescimento & desenvolvimento , Larva/parasitologia , Larva/fisiologia , Aprendizagem , Microextração em Fase Sólida , Tephritidae/crescimento & desenvolvimento , Tephritidae/parasitologia , Vespas/crescimento & desenvolvimento
18.
Insect Sci ; 23(4): 603-11, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25641835

RESUMO

Lysiphlebus testaceipes (Hymenoptera: Braconidae: Aphidiinae) is a generalist endoparasitoid attacking more than 100 aphid species. In L. testaceipes, wing fanning is a main male courtship display evoked by a female-borne sex pheromone. However, no information is available on the characteristics and behavioral role of male fanning during courtship in this parasitoid. Here, the courtship behavior of a wild strain of L. testaceipes was quantified and the male wing fanning performances were analyzed through high-speed video recordings and examined in relation to mating success. Courtship sequence of wild L. testaceipes did not substantially differ from that previously reported for other populations mass reared on aphids. We observed that the male courtship duration did not affect mating success. However, video analysis revealed that the males producing high-frequency fanning signals achieved higher mating success over those that display low-frequency fanning. Wing fanning before successful and unsuccessful courtship differed in amplitude of wing movements and alignment toward the mate, highlighting that frontal courtship positively influence the female mating decisions. This study increases knowledge on sexual behavior in a key parasitoid of aphids, highlighting the importance of wing fanning among the range of sensory modalities used in the sexual communication of L. testaceipes. From a practical point of view, this information is useful in L. testaceipes-based biocontrol strategies, since it can help to establish parameters for quality checking of mass-reared wasps over time.


Assuntos
Afídeos/parasitologia , Vespas/fisiologia , Animais , Copulação , Corte , Feminino , Masculino , Comportamento Sexual Animal , Asas de Animais/fisiologia
19.
Biomed Res Int ; 2016: 7827615, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26989691

RESUMO

Herbivorous activity induces plant indirect defenses, as the emission of herbivorous-induced plant volatiles (HIPVs), which could be used by parasitoids for host location. Psyttalia concolor is a larval pupal endoparasitoid, attacking a number of tephritid flies including B. oleae. In this research, we investigated the olfactory cues routing host location behavior of P. concolor towards B. oleae larvae infesting three different olive cultivars. VOCs from infested and healthy fruits were identified using GC-MS analyses. In two-choice behavioral assays, P. concolor females preferred infested olive cues, which also evoked ovipositional probing by female wasps. GC-MS analysis showed qualitative and quantitative differences among volatiles emitted by infested and healthy olives. Volatile emissions were peculiar for each cultivar analyzed. Two putative HIPVs were detected in infested fruits, regardless of the cultivar, the monoterpene (E)-ß-ocimene, and the sesquiterpene (E-E)-α-farnesene. Our study adds basic knowledge to the behavioral ecology of P. concolor. From an applied point of view, the field application of the above-mentioned VOCs may help to enhance effectiveness of biological control programs and parasitoid mass-rearing techniques.


Assuntos
Interações Hospedeiro-Parasita/efeitos dos fármacos , Himenópteros/efeitos dos fármacos , Tephritidae/efeitos dos fármacos , Compostos Orgânicos Voláteis/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Feminino , Frutas/efeitos dos fármacos , Frutas/parasitologia , Herbivoria/efeitos dos fármacos , Himenópteros/patogenicidade , Larva/efeitos dos fármacos , Larva/parasitologia , Olea/química , Olea/parasitologia , Tephritidae/parasitologia , Compostos Orgânicos Voláteis/química
20.
NeuroRehabilitation ; 35(1): 1-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24990001

RESUMO

BACKGROUND: While the positive effects of rehabilitation on physical functioning are well documented in stroke literature, more controversial results arise from the evaluation of the impact on quality of life. OBJECTIVE: The aim of the present study is to examine the associations among functional status and different measures of quality of life in a sample of inpatients undergoing rehabilitation programmes, and to consider the role of psychological distress, coping strategies and social support. METHODS: Twenty-nine stroke survivors were evaluated at the admission to a hospital-based Rehabilitation Unit and just before discharge. Questionnaires for the evaluation of functional status, health-related QoL, individualised QoL, psychological distress, coping strategies and social support were administered to them. RESULTS: While functional status improves significantly after treatment, individualised evaluations of QoL seem to be less affected. Adaptive coping strategies and social support showed significant correlations with positive outcomes on specific QoL domains, whereas psychological distress was associated with negative outcomes. CONCLUSIONS: The data from the present study support the evidence that different measures of QoL and functional status are not strongly associated one another, and that psychological distress, coping strategies and social support can be significantly related to specific outcome measures.


Assuntos
Hospitalização , Qualidade de Vida/psicologia , Recuperação de Função Fisiológica , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/psicologia , Sobreviventes/psicologia , Adaptação Psicológica , Adulto , Idoso , Feminino , Hospitalização/tendências , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Alta do Paciente/tendências , Apoio Social , Inquéritos e Questionários
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