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1.
Insects ; 13(2)2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35206748

RESUMO

Despite their importance as biological control agents, zoophytophagous dicyphine mirids can produce economically important damage. We evaluated the phytophagy and potential impact on tomato plants of Dicyphus cerastii and Nesidiocoris tenuis. We developed a study in three parts: (i) a semi-field trial to characterize the type of plant damage produced by these species on caged tomato plants; (ii) a laboratory experiment to assess the effect of fruit ripeness, mirid age, and prey availability on feeding injuries on fruit; and (iii) a laboratory assay to compare the position of both species on either fruit or plants, over time. Both species produced plant damage, however, although both species produced scar punctures on leaves and necrotic patches on petioles, only N. tenuis produced necrotic rings. Both species caused flower abortion at a similar level. Overall, N. tenuis females produced more damage to tomato fruit than D. cerastii. There was an increased frequency of D. cerastii females found on the plants over time, which did not happen with N. tenuis. Our results suggested that, although D. cerastii caused less damage to fruit than N. tenuis, it still fed on them and could cause floral abortion, which requires field evaluation and caution in its use in biological control strategies.

2.
Foods ; 11(4)2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35206024

RESUMO

Consumers' food preferences increasingly meet concerns of authenticity, health, origin, and sustainability, altogether attributes embodied in rural provenance food products. The dynamics of production, commercialization, and availability of these products in urban centers are growing stronger. This study aims to explore rural provenance food consumption and underlying motivations, the consumers' images of products and provenance areas, and the influence of rural ties in consumption. Data from a survey directed to 1554 consumers of 24 urban specialty stores located in three Portuguese cities were analyzed. The analysis is based on the differences between frequent and sporadic consumers of Portuguese rural provenance food products. The two groups significantly differ in the reasons provided to acquire the products. Those who buy and consume these products more frequently especially value sensorial features, convenience, national provenance, and the impacts on rural development. Additionally, the motivations to choose rural provenance foods tend to pair with positive images of those products and of their territories of origin. This is intrinsically connected with familiarity, a nuclear notion that encompasses the symbolic images of the products and their origins as actual connections (familiar and otherwise) to rural contexts.

3.
Insects ; 12(6)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200391

RESUMO

Dicyphine mirids are important biological control agents (BCAs) in horticultural crops. Dicyphus cerastii Wagner can be found in protected tomato crops in Portugal, and has been observed feeding on several tomato pests. However, the predation capacity of this species is poorly studied. In order to investigate the predation capacity of D. cerastii, and how it is affected by prey size and mobility, we evaluated the functional response (FR) and predation rate of female predators on different densities of four prey species: Myzus persicae 1st instar nymphs (large mobile prey), Bemisia tabaci 4th instar nymphs, Ephestia kuehniella eggs (large immobile prey) and Tuta absoluta eggs (small immobile prey). Experiments were performed on tomato leaflets in Petri dish arenas for 24 h. Dicyphus cerastii exhibited type II FR for all prey tested. The predator effectively preyed upon all prey, consuming an average of 88.8 B. tabaci nymphs, 134.4 E. kuehniella eggs, 37.3 M. persicae nymphs and 172.3 T. absoluta eggs. Differences in the FR parameters, attack rate and handling time, suggested that prey size and mobility affected predation capacity. Considering the very high predation rates found for all prey species, D. cerastii proved to be an interesting candidate BCA for tomato crops.

4.
Insects ; 12(1)2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33379226

RESUMO

Helicoverpa armigera is one of the key pests affecting processing tomatoes and many other crops. A three-year study was conducted to describe the oviposition preferences of this species on determinate tomato plants (mainly the stratum, leaf, leaflet, and leaf side) and the spatial pattern of the eggs in the field, to form a sequential sampling plan. Eggs were found mainly in the exposed canopy, on leaves a (upper stratum) and b (upper-middle stratum) and significantly fewer eggs on leaf c (middle-lower stratum) below flower clusters. This vertical pattern in the plant was found in all phenological growth stages. The spatial pattern was found to be aggregated, with a trend towards a random pattern at lower densities. A sequential sampling plan was developed, based on Iwao's method with the parameters of Taylor's power law, with minimum and maximum sample size of 20 and 80 sample units (plants), respectively (two leaves/plant). For its validation, operating characteristic (OC) and average sample number (ASN) curves were calculated by means of simulation with independent data sets. The ß-error was higher than desirable in the vicinity of the economic threshold, but this sampling plan is regarded as an improvement both in effort and precision, compared with the fixed sample plan, and further improvements are discussed.

5.
Evol Appl ; 12(4): 679-691, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30976302

RESUMO

Human-mediated introductions of species may have profound impacts on native ecosystems. One potential impact with largely unforeseen consequences is the potential admixture of introduced with autochthonous species through hybridization. Throughout the world, bumblebees have been deliberately introduced for crop pollination with known negative impacts on native pollinators. Given the likely allochthonous origin of commercial bumblebees used in Portugal (subspecies Bombus terrestris terrestris and B. t. dalmatinus), our aim was to assess their putative introgression with the native Iberian subspecies B. terrestris lusitanicus. We analysed one mitochondrial gene, cytochrome c oxidase subunit I (COX1) and genomic data involving thousands of genome-wide restriction-site-associated DNA markers (RAD-seq). In the mitochondrial COX1 analyses, we detected one relatively common haplotype in commercial bumblebees, also present in wild samples collected nearby the greenhouses where the commercial hives are used. In the RAD-seq analysis, we found a clear genetic differentiation between native and commercial lineages. Furthermore, we detected candidate hybrids in the wild, as well as putatively escaped commercial bumblebees, some of which being potentially fertile males. Although we cannot assess directly the fitness effects of introgressed alleles, there is a risk of maladaptive allele introgression to the local bumblebee subspecies, which can negatively impact autochthon populations. One immediate recommendation to farmers is for the proper disposal of hive boxes, after their use in greenhouses, so as to minimize the risk of escapees contaminating native populations. On the other hand, the feasibility of using local subspecies B. t. lusitanicus, preferably with local production, should be evaluated.

6.
Pest Manag Sci ; 72(4): 660-70, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25960129

RESUMO

BACKGROUND: A binary co-occluded mixture (HearSP1B:LB6) of Helicoverpa armigera single nucleopolyhedrovirus (HearNPV) variants was previously found to be highly pathogenic under laboratory conditions. The insecticidal efficacy and persistence of this mixture were determined in greenhouse and field-grown tomato crops in Spain and Portugal. RESULTS: Concentrations of 10(9) -10(11) occlusion bodies (OBs) L(-1) of HearSP1B:LB6 resulted in 89-100% mortality of larvae on treated tomato plants in growth chambers. In protected tomato crops, application of 10(10) OBs L(-1) of HearSP1B:LB6 was as effective as Bacillus thuringiensis (Bt) and spinosad in reducing the percentage of damaged fruits, and resulted in higher larval mortality than the Bt treatment. In open-field tomato crops, virus treatments were as effective in reducing the percentage of damaged fruit as spinosad, Bt and chlorpyrifos treatments. The persistence of the insecticides on tomato plants was negatively correlated with solar radiation in both field and greenhouse settings. Residual insecticidal activity of OBs on protected tomato crops at 6 days post-application was 55 and 35% higher than that of Bt and spinosad respectively. On field-grown tomato, OB persistence was significantly lower than with spinosad or chlorpyrifos. CONCLUSION: The efficacy and persistence of HearSP1B:LB6 OBs were comparable with those of commercial insecticides in both field and greenhouse tomato crops. Future studies should focus on reducing application rates to determine insecticidal efficacy at lower OB concentrations. © 2015 Society of Chemical Industry.


Assuntos
Variação Genética , Lepidópteros/virologia , Nucleopoliedrovírus/genética , Nucleopoliedrovírus/fisiologia , Solanum lycopersicum/crescimento & desenvolvimento , Animais , Ambiente Controlado , Europa (Continente) , Laboratórios , Larva/virologia
7.
Viseu; s.n; 20150000. 136 p. ilustr, tabelas.
Tese em Português | BDENF - Enfermagem | ID: biblio-1253620

RESUMO

Enquadramento: A Artrite Reumatóide (AR) é uma patologia com profundas implicações na funcionalidade das pessoas, com efeitos significativos não só ao nível do funcionamento físico, mas também a nível emocional, familiar, social e económico. Objetivos: Avaliar a funcionalidade das pessoas com artrite reumatóide e analisar a sua relação com as variáveis sócio demográficas, clínicas, dor e qualidade do sono. Métodos: Trata-se de um estudo não experimental, transversal, descritivo-correlacional e de caráter quantitativo, que foi realizado numa amostra não probabilística por conveniência, constituída por 75 pessoas com o diagnóstico de artrite reumatóide, acompanhadas na Unidade de Dor, na Consulta de Reumatologia e na Medicina Física de Reabilitação do CHTV, EPE. Para a mensuração das variáveis utilizou-se um instrumento de colheita de dados que integra uma secção de caracterização sócio demográfica e clínica, o Índice da Qualidade de Sono de Pittsburgh ­ PSQI e o Health Assessment Questionnaire ­ HAQ. Resultados: Constatou-se que 60,0% dos inquiridos apresenta dificuldades/incapacidades leves no desempenho das atividades da vida diária, 32,0% apresenta já dificuldades moderadas e 8,0% incapacidade grave, sendo que o valor médio da funcionalidade global avaliado por meio do HAQ foi de 1,48, o que revela a existência de uma incapacidade moderada na nossa amostra. Das variáveis sócio demográficas, a idade (p=0,003), a situação laboral (p=0,000), a escolaridade (p=0,006) e os rendimentos mensais (p=0,001) têm influência no estado funcional das pessoas com AR. Das variáveis clínicas, a intensidade da dor (p=0,007) e o tempo de diagnóstico da doença (p=0,013) mostraram relacionarem-se com a funcionalidade. Em relação à qualidade do sono, apenas existem diferenças estatísticamente significativas nas subescalas "levantar-se" (p=0,030) e "caminhar" (p=0,034), sendo que a má qualidade de sono configurou-se em 94,7% dos inquiridos. Conclusão: As evidências encontradas neste estudo referem que a idade, a situação laboral, a escolaridade, os rendimentos mensais, o tempo de diagnóstico, a intensidade da dor e a qualidade do sono, associam-se a uma pior funcionalidade nas pessoas com AR. O diagnóstico precoce, a adoção de medidas para a promoção da boa qualidade do sono, a aplicação de medidas farmacológicas e não farmacológicas para o alívio da dor, e ações de formação direcionadas aos doentes com AR, devem ser estratégias a desenvolver junto desta população, numa tentativa de minimizar o impacto negativo que esta doença acarreta.


Framework: Rheumatoid arthritis is a disease with profound implications in the functionality of people, with significant effects, not only in terms of physical functioning, but also in the emotional, family, social and economic. Objectives: To evaluate the functionality of people with rheumatoid arthritis and analyze its relationship with the socio demographic variables, clinical, pain and quality of sleep. Methods: It is a non-experimental, cross-sectional, descriptive and correlational and quantitative character study, which was carried out in a non-probabilistic convenience sample consisting of 75 people diagnosed with rheumatoid arthritis followed in the Pain Unit, at the Rheumatology Consultation and Physical Medicine Rehabilitation CHTV, EPE. For the measurement of the variables used a data collection instrument that integrates a section of sociodemographic and clinical characterization, the Index of Sleep Quality Pittsburgh - PSQI and the Health Assessment Questionnaire - HAQ. Results: We found that 60.0% of respondents have difficulties/mild disability in performing activities of daily living, 32.0% already presents moderate difficulties, and 8.0% severe disability. The average value the overall functionality assessed by HAQ was 1.48, which reveals a moderate disability in our sample. The sociodemographic variables, age (p=0.003), the employment status (p=0.000), schooling (p=0.006) and monthly income (p = 0.001) influence the functional status of people with RA. Of clinical variables, the intensity of pain (p=0.007) and the time of diagnosis of the disease (p=0.013) showed they relate to the functionality. Regarding the quality of sleep, there are only statistically significant differences in the subscales "get up" (p=0.030) and "walking" (p=0.034) and that poor sleep set up in 94.7% of respondents. Conclusion: The evidence from this study indicates that age, employment status, education level, monthly income, time of diagnosis, pain intensity and sleep quality are associated with a worse function in people with RA. Early diagnosis, the adoption of measures to promote good sleep quality, the application of pharmacological and non-pharmacological measures for pain relief, and training activities directed to patients with RA should be strategies to be developed with this population, in an attempt to minimize the negative impact that this disease causes.


Assuntos
Artrite Reumatoide , Sono , Atividades Cotidianas
8.
PLoS One ; 8(7): e68241, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23844173

RESUMO

The occurrence of polyandry in Planococcuscitri, presumed by earlier observations of mating behavior, was confirmed using microsatellite genotyping of pools of over 400 eggs resulting from controlled crosses of one female with two males. The genetic contribution of both mated males was confirmed in 13 out of 43 crosses. In three crosses it was possible to determine that only the first male fertilized the eggs, which may be due to sperm competition or unviable sperm supply. The microsatellite analysis also allowed the confirmation of aspects of the chromosomal inheritance detected previously in cytogenetic studies in Planococcuscitri, namely that only one of the alleles is transmitted by the male, indicating that the males are functionally haploid, supporting the observation of Paternal Genome Elimination (PGE) in these insects.


Assuntos
Hemípteros/genética , Comportamento Sexual Animal , Alelos , Animais , Cruzamentos Genéticos , Feminino , Genes de Insetos , Loci Gênicos , Genótipo , Masculino , Repetições de Microssatélites
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