6 resultados para protection application
em CentAUR: Central Archive University of Reading - UK
Resumo:
The effectiveness of a formulated product containing spores of the naturally occurring fungus Paecilomyces lilacinus, strain 251, was evaluated against root-knot nematodes in pot and greenhouse experiments. Decrease of second-stage juveniles hatching from eggs was recorded by using the bio-nematicide at a dose of 4 kg ha(-1), while a further decrease was recorded by doubling the dose. However, the mortality rate decreased by increasing the inoculum level. Application of P. lilacinus and Bacillus firmus, singly or together in pot experiments, provided effective control of second-stage juveniles, eggs or egg masses of root-knot nematodes. In a greenhouse experiment, the bio-nematicide was evaluated for its potential to control root-knot nematodes either as a stand-alone method or in combination with soil solarization. Soil was solarized for 15 d and the bio-nematicide was applied just after the removal of the plastic sheet. Soil solarization for 15 d either alone or combined with the use of P. lilacinus did not provide satisfactory control of root-knot nematodes. The use of oxamyl, which was applied 2 weeks before and during transplanting, gave results similar to the commercial product containing P. lilacinus but superior to soil solarization. (C) 2007 Elsevier Ltd. All rights reserved.
Resumo:
In a glasshouse experiment using potted strawberry plants (cv. Cambridge Favourite) as hosts, the effect of selected fungal antagonists grown on 25 or 50 g of mushroom compost containing autoclaved mycelia of Agaricus bisporus, or wheat bran was evaluated against Armillaria mellea. Another glasshouse experiment tested the effect of application time of the antagonists in relation to inoculations with the pathogen. A significant interaction was found between the antagonists, substrates and dose rates. All the plants treated with Chaetomium olivaceum isolate Co on 50 g wheat bran survived until the end of the experiment which lasted 482 days, while none of them survived when this antagonist was added to the roots of the plants on 25 g wheat bran or 25 or 50 g mushroom compost. Dactylium dendroides isolate SP had a similar effect, although with a lower host survival rate of 33.3%. Trichoderma hamatum isolate Tham 1 and T. harzianum isolate Th23 protected 33.3% of the plants when added on 50 g and none when added on 25 g of either substrate, while 66.7% of the plants treated with T. harzianum isolate Th2 on 25 g, or T viride isolate TO on 50 g wheat bran, survived. Application of the antagonists on mushroom compost initially resulted in development of more leaves and healthier plants, but this effect was not sustained. Eventually, plants treated with the antagonists on wheat bran had significantly more leaves and higher health scores. The plants treated with isolate Th2 and inoculated with Armillaria at the same time had a survival rate of 66.7% for the duration of the experiment (475 days), while none of them survived that long when the antagonist and pathogen were applied with an interval of 85 days in either sequence. C. olivaceum isolate Co showed a protective effect only, as 66.7% of the plants survived when they were treated with the antagonist 85 days before inoculation with the pathogen, while none of them survived when the antagonist and pathogen were applied together or the infection preceded protection.
Resumo:
The present paper investigates pesticide application types adopted by smallholder potato producers in the Department of Boyacá , Colombia. In this region, environmental, health and adverse economic effects due to pesticide mis- or over-use respectively have been observed. Firstly, pesticide application types were identified based on input-effectiveness. Secondly, their determinants of adoption were investigated. Finally suggestions were given to develop intervention options for transition towards a more sustainable pesticide use. Three application types were identified for fungicide and insecticide. The types differed in terms of input (intensity of pesticide application), effect (damage control), frequency of application, average quantity applied per application, chemical class, and productivity. Then, the determinants of different pesticide application types were investigated with a multinomial logistic regression approach and applying the integrative agent centred (IAC) framework. The area of the plot, attendance at training sessions and educational and income levels were among the most relevant determinants. The analysis suggested that better pesticide use could be fostered to reduce pesticide-related risks in the region. Intervention options were outlined, which may help in targeting this issue. They aim not only at educating farmers, but to change their social and institutional context, by involving other agents of the agricultural system (i.e. pesticide producers), facilitating new institutional settings (i.e. cooperatives) and targeting social dynamics (i.e. conformity to social norms).
Resumo:
Pollination is one of the most important ecosystem services in agroecosystems and supports food production. Pollinators are potentially at risk being exposed to pesticides and the main route of exposure is direct contact, in some cases ingestion, of contaminated materials such as pollen, nectar, flowers and foliage. To date there are no suitable methods for predicting pesticide exposure for pollinators, therefore official procedures to assess pesticide risk are based on a Hazard Quotient. Here we develop a procedure to assess exposure and risk for pollinators based on the foraging behaviour of honeybees (Apis mellifera) and using this species as indicator representative of pollinating insects. The method was applied in 13 European field sites with different climatic, landscape and land use characteristics. The level of risk during the crop growing season was evaluated as a function of the active ingredients used and application regime. Risk levels were primarily determined by the agronomic practices employed (i.e. crop type, pest control method, pesticide use), and there was a clear temporal partitioning of risks through time. Generally the risk was higher in sites cultivated with permanent crops, such as vineyard and olive, than in annual crops, such as cereals and oil seed rape. The greatest level of risk is generally found at the beginning of the growing season for annual crops and later in June–July for permanent crops.
Resumo:
The Sustainable Value approach integrates the efficiency with regard to environmental, social and economic resources into a monetary indicator. It gained significant popularity as evidenced by diverse applications at the corporate level. However, its introduction as a measure adhering to the strong sustainability paradigm sparked an ardent debate. This study explores its validity as a macroeconomic strong sustainability measure by applying the Sustainable Value approach to the EU-15 countries. Concretely, we assessed environmental, social and economic resources in combination with the GDP for all EU-15 countries from 1995 to 2006 for three benchmark alternatives. The results show that several countries manage to adequately delink resource use from GDP growth. Furthermore, the remarkable difference in outcome between the national and EU-15 benchmark indicates a possible inefficiency of the current allocation of national resource ceilings imposed by the European institutions. Additionally, by using an effects model we argue that the service degree of the economy and governmental expenditures on social protection and research and development are important determinants of overall resource efficiency. Finally, we sketch out three necessary conditions to link the Sustainable Value approach to the strong sustainability paradigm.
Resumo:
Cet article porte sur l’analyse de trois configurations institutionnelles de la protection de l’enfance : celle en place au Burkina Faso, en Belgique et au Québec. Pour chaque configuration, le texte explore les transformations qui ont marqué le passage de la prise en charge exclusive de l’enfant par la famille vers la présence accrue de l’État et la manière dont la Convention internationale des droits de l’enfant de 1989 a influencé ce passage. Il montre, au travers d’une lecture historique, que l’implication de l’État dans la protection des enfants a connu des formes et des modalités variables selon le temps et l’espace. L’approche actuelle en matière de protection de l’enfance au Nord et au Sud, approche largement inspirée de la perspective des droits, représente un défi tant pour les intervenants que pour les familles, car son application dépend à fois des ressources disponibles pour aider les enfants et les familles en difficulté, de la capacité d’action des institutions publiques et de l’efficacité des interventions. This article deals with the analysis of three institutional configurations of child protection: those in Burkina Faso, in Belgium, and in Québec. With respect to each configuration, the text explores the changes from situations in which the family had sole control of the child to those where the State played a greater role, and the manner in which the 1989 International Convention on the Rights of the Child has affected such changes. It shows, through a reading of history, that the involvement of the State in child protection has gone through different forms and stages over time and space. The current strategies as regards child protection in the North and in the South—an approach that is largely subject to a legal perspective—represent a challenge both for intervenors and for families, since their application depends on the resources available for helping children and families in difficulty, on the ability of the public institutions to intervene, and on the efficiency of such interventions.