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3430 Uppsatser om Biological control agents - Sida 1 av 229

Side effects of biological control agents in agriculture : does the bacteria Bacillus amyloliquefaciens affect the earthworm Aporrectodea longa?

Pathogenic microorganisms pose a big threat towards food production. Meanwhile, negative impacts on humans and environment are seen by the use of pesticides. Biological control agents are an alternative to the use of chemical pesticides, and plant-growth promoting rhizobacteria, such as Bacillus amyloliquefaciens has been shown to have good properties as biocontrol agents. Before these bacteria can be used commercially their impact on other soil organisms has to be evaluated. This thesis looks into what biocontrol bacteria are and how they might affect earthworms.

Biological control of powdery mildew in greenhouse produced cucumber : an evaluation of two microbiological control agents

Powdery mildew is a serious problem in both field and greenhouse cucumber production and can cause serious infection and radically reduced yields. Today, powdery mildew is the main disease in greenhouse produced cucumber. Disease control should preferably be both efficient and environmentally friendly, which is not easy to achieve at all times. Alternatives to chemical control of powdery mildews are biological control, physical control, non-fungicide control and cultivation of resistant or tolerant varieties. Biological control can be described as the suppression of damaging activities inflicted of a harmful organism by one or more other organisms, which are called antagonists or natural enemies. In Sweden, there are currently no registered biological control products available to control cucumber powdery mildew. The aim of this study was to investigate the effect of two biological control products in order to evaluate their ability to prevent or reduce powdery mildew infection to an acceptable level in greenhouse produced cucumber. In the experiments, different application regimes were also studied.

Stereotyper i den virtuella världen. Hur visuella intryck påverkar deltagares uppfattningar av virtuella agenter

The purpose of this study is to examine how participants perceive virtual agents shown on a computer display. In particular, it is explored to what extent participants transfer gender and attraction stereotypes that are commonly applied in the physical world to virtual agents. Previous related studies have often explored only text or voice interfaces, without any visually appearing agents, and here indeed found evidence for a transfer of gender stereotypes. Our hypothesis was that the addition of a visual agent interface would reinforce this effect. The results support our hypothesis that participants transfer human gender and attraction stereotypes onto virtual agents, as well as that these processes are affected by the visual representations of the agents..

Åkertistel : biologi och icke-kemisk bekämpning

A growing problem in Swedish herbicide free agriculture, the Canadian thistle has been the object of several new trials, seeking methods for non-chemical weed control. The new trials have mainly confirmed earlier experiences; that the most successful methods of control are springtime ploughing, repeated cutting and competition from a stout crop. Row hoeing has also been proven effective. As opposed to earlier recommendations, half season fallow has shown to be a risky and often ineffective method of control. Trials regarding biological methods have shown that above others thistle rust (Puccinia punctiformis) may have the potential of controlling Canadian thistle the future. .

Optiska egenskapers påverkanav möjligheten att trycka eftermålvärden i ISO 12647-2.

This thesis investigates how the optical properties of paperboard influences printing with targets in ISO 12647-2. The targets for optical properties in ISO 12647-2 are defined for paperboard without optical brightening agents and fluorescent brightening agents wich makes it difficult to reach the targets when printing paperboard containing these agents.Seven different types of paperboard, some with and some without the agents, have been printed and instrumentally andvisually measured to see if there is any deviation from the standard targets and if it shows visually.The result shows that paperboard containing optical brightening agents and fluorescent brightening agents can print with targets in ISO 12647-2 but in many measurments the difference between the types of paperboard were to small to assess. The differences between the types of paperboard in the instrumental measurements did not fully correspond with the waythe panel appraised them visually..

Biologiska bekämpningsmetoder i hemträdgården :

Biological pest management is defined as control of pests using their natural enemies. This method has been used in Sweden since the 1970´s and it has been developed ever since. Biological pest management is today relatively common among commercial growers but there are good possibilities to apply this method in the home gardens as well. The aim with this thesis is to compile a report from both the companies that are marketing the products and the home gardener´s point of view. This should give a better understanding of the market and how it could be improved. We will give examples of products that represent the different kinds of organisms that are being used in biological pest management. Our hope is that this will be an introduction to all interested in biological pest management. The legislations regarding registration of organisms are still a matter of discussion and are causing problems to producers, distributors and the market in general. Why isn´t biological pest management more common in the home garden? The main reason appears to be the lack of knowledge in the subject. What are the benefits using biological pest management when it requires so much knowledge and it´s more expensive than conventional pest management? With the environmental problems we face today, we hope that every single gardener has an interest in developing an environment as clean as possible, even if only in one's own backyard..

Livespelningars organisering : Hur organiseras och styrs dagens liveunderhållning?

The purpose of our study is to provide a deeper understanding of the organization at alive concert. We want to identify and bring together different agents implicit knowledge and make it explicit. We contribute to the theoretical discussion by examining how liveconcerts are organized and why, what goals there are to participate in the organizationof the concerts as well as how the organization manage and control towards these goals.Our study is based on 15 interviews with different agents involved in the creation of liveconcerts. The study has shown that the organization of live concerts is similar to atemporary, imaginary organization because there is a temporary and implicit structure.Relationships are created by the agents? cooperation and customer relations with thesubcontractors.

The efficiency of the newly launched predatory mite Amblydromalus limonicus : biological control of thrips in cucumber

In this study, the efficiency of a newly launched predatory mite, Amblydromalus limonicus, has been examined for its potential to use as a biological control agent in cucumber production. A. limonicus can be used for biological control of two thrips species, Frankliniella occidentalis and Thrips tabaci. Field trials were conducted in greenhouses of two conventional cucumber growers in Scania, the southern part of Sweden. The basic control agent used against thrips was the predatory mite Amblyseius swirskii. In selected areas, additional A.

Mäklaryrket ur ett jämställdhetsperspektiv

The Profession of Real Estate Agents has by tradition been a male profession. However during later years the profession has changed. It is now many young women that are pursuing a career as a Real Estate Agent.In the light of this background we have researched how Real Estate Agents employed by Fastighetsbyrån and Svensk Fastighetsförmedling perceive their profession from an equality perspective.The investigation has been limited to include the counties of Värmland and Närke and have been conducted by interviewing Real Estate Agents of different age and sex and the managers of the firms.The study show that the Real Estate Agents perceive their profession in a positive way and that the work is divided equal. However it emerged that there were a division regarding different real estate types in certain agencies. The Real Estate Agents believe that the gender of the manager is of no importance.

Biologisk bekämpning av Fusarium graminearum

Fusarium graminearum causes reduction in both yield and quality in cereal grain worldwide. One of the diseases it can cause is Fusarium Head Blight (FHB). Both sexually and asexually produced spores can infect living plants. Asexual conidia are produced in the mycelium while sexual ascospores form in asci in perithecia on debris. In biological control, living organsims are used to control pests and diseases.

The potential of entomopathogenic fungal isolates as an environmentally friendly management option against Acanthoscelides obtectus

The bean bruchid, Acanthoscelides obtectus is a major threat to bean production. In Ethiopia, where this study was performed, the damage by bruchids on stored beans has been reported to reach up to 38%. To use the isolates Beauveria bassiana and Metarhizium anisopliae in the management of A. obtectus can be an environmentally safe alternative for controlling the pest. In the present work the aim was to examine if the four chosen fungal isolates, B.

Vilka faktorer har inverkan på motivationen, utifrån fastighetsmäklareperspektivet? : Ändras de här faktorerna under mäklarkarriären?

The aim of the study was to understand how the family home secretary reasons and thinks and how they express themselves in their actions towards the family home?s biological children. The method used is qualitative semi-structured interviews, involving six family home secretaries from four different municipalities. The results were analyzed with the help of two theories ? the theory of grassroots bureaucracy and the sociology of childhood theory.

Skogen - vårt biologiska kulturarv

This article deals with the woodlands as a biological cultural heritage and how it is taken care of in the protected woodlands in Skåne, in the south of Sweden, especially the deciduous trees which is dominated by beech. High biological values have emerged as a result of grazing and different kinds of forestry. The protected woodlands have been ripped of its cultural influences which changes the biological values on which the original reasons for protection was founded..

"Alldeles utmärkt" eller "tungt som fan"? : En studie av fosterfamiljers egna barns syn på sin situation sett ut ett genusperspektiv

The purpose of this essay was to examine, from a gender perspective, how biological children in foster families experience the situation of living with foster siblings. The material consists of ten interviews. We searched answers to the questions:1. In what way have the biological childrens relations to parents, biological siblings and foster siblings changed through the placement?2.

Fastighetsmäklare : varför så dåligt rykte?

Aim: Many people react negatively when they find out that I work as an estate agent. They believe that estate agents earn more money then they should. What many do not know is how hard we must work and that it doesn´t suit someone who is looking for an 8-17 work. As an estate agent I thought it would be interesting to found out why the estate agents have such a bad reputation.Method: This essay is based on the interviews with estate agents and branch organizations but also on newspaper articles about real estate agents. Theory is collected marketing, where I have concentrate on concepts of branding, positioning, communication and image.Result & Conclusions: The factors, which I found in my investigation, that have an effect to the bad reputation are; media, commission, the customers and the bidding.

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