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1.
PeerJ ; 8: e8746, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32257638

RESUMEN

Agricultural intensification is one of the major drivers of biotic homogenization and has multiple levels ranging from within-field management intensity to landscape-scale simplification. The enhancement of invertebrate assemblages by establishing new, semi-natural habitats, such as set-aside fields can improve biological pest control in adjacent crops, and mitigate the adverse effect of biotic homogenization. In this study we aimed to examine the effects of ecological intensification in winter wheat fields in Hungary. We tested how pests and their natural enemies were affected at different spatial scales by landscape composition (proportion of semi-natural habitats in the surrounding matrix), configuration (presence of adjacent set-aside fields), and local field management practices, such as fertilizer (NPK) applications without applying insecticides. We demonstrated that at the local scale, decreased fertilizer usage had no direct effect either on pests or their natural enemies. Higher landscape complexity and adjacent semi-natural habitats seem to be the major drivers of decreasing aphid abundance, suggesting that these enhanced the predatory insect assemblages. Additionally, the high yield in plots with no adjacent set-aside fields suggests that intensive management can compensate for the lower yields on the extensive plots. Our results demonstrated that although complexity at the landscape scale was crucial for maintaining invertebrate assemblages, divergence in their response to pests and pathogens could also be explained by different dispersal abilities. Although the landscape attributes acted as dispersal filters in the organization of pest and pathogen assemblages in croplands, the presence of set-aside fields negatively influenced aphid abundance due to their between-field isolation effect.

2.
Wien Med Wochenschr ; 154(9-10): 242-5, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15244050

RESUMEN

Tick-borne encephalitis (TBE) is a communicable disease caused by a flavi-virus, ticks being the main vectors. The nervous system is affected, four clinical features of different severity are observed: meningitis, meningoencephalitis, meningoencephalomyelitis, meningoradiculoneuritis. TBE is a preventable disease, which is rapidly becoming a growing public health problem in Europe. So far no causal treatment is possible but an efficient, safe vaccination is available. During the 6th meeting of the International Scientific Working Group on TBE with the main conference issue "Tick-borne encephalitis in childhood" an international consensus was achieved. In countries where TBE is endemic--and not prevented by immunization--both children and adults are affected. The disease in children is generally milder, although severe illness may occur and even lead to permanent impairment of the quality of life due to neuropsychological sequelae. Therefore immunization should be offered to all children living in or traveling to endemic areas.


Asunto(s)
Encefalitis Transmitida por Garrapatas/prevención & control , Enfermedades Endémicas , Flavivirus/inmunología , Vacunas Virales/administración & dosificación , Adolescente , Adulto , Austria , Niño , Preescolar , Encefalitis Transmitida por Garrapatas/inmunología , Europa (Continente) , Humanos , Lactante , Vacunación Masiva , Vacunas Virales/inmunología
3.
Environ Biosafety Res ; 3(4): 225-31, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-16028799

RESUMEN

Impact assessment studies rely on relevant sampling methods. Correct evaluation of methods can be done by their concurrent use in the same sampling site and period. Collecting webs of Theridion impressum L. Koch (Araneae: Theridiidae) may serve as an arthropod sampling method: empty cuticles of prey items remain attached to the back side of the leaves with adhesive silk. Our study aimed to compare the applicability of the two methods concurrently (spider web survey and whole plant visual sampling) in a risk assessment study. The spider web survey recorded more predatory insect families than the whole plant visual sampling. Both methods were able to detect significant differences in the quantity of predatory insects in Bt vs. isogenic plots, but not in the same taxa (Nabidae: spider-web, 2001, Bt > Iso; Coccinellidae: plant sampling, 2001, Iso > Bt; Welsh-test, P < 0.05); thus, they could not confirm each other. The lack of confirmation can be explained by differences in the sensitivity and selectivity of the two methods. A web survey of T. impressum has the practical advantage that although we concentrate only on the one species during field sampling, we gain additional information on a wide range of foliage-dwelling arthropods. Due to several biological uncertainties, interpretation and explanation of the results remain problematic. Thus, additional research--based on in-situ observation and recording of T. impressum-prey interactions--is necessary before we could propose web survey method as a complementary tool in ecological impact assessment.


Asunto(s)
Bacillus thuringiensis/patogenicidad , Plantas Modificadas Genéticamente , Arañas , Zea mays/química , Zea mays/microbiología , Animales , Recolección de Datos , Monitoreo del Ambiente/métodos , Cadena Alimentaria , Hojas de la Planta , Dinámica Poblacional , Conducta Predatoria , Medición de Riesgo
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