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536 Uppsatser om Plants - Sida 29 av 36

Fritidsodlarens främsta försvar : trädgårdsväxter som skydd mot skadedjur

Fritidsodling är ett stort intresse i Sverige och det odlas trädgårdsväxter både för prydnad och för konsumering. Det finns ett stort antal skadedjur som kan förstöra växterna och reducera skörd. Denna litteraturstudie undersöker om det finns trädgårdsväxter som kan påverka skadedjuren negativt. Det ska göras genom att repellera/reducera skadedjuren, attrahera nyttodjur eller påverka odlingsmiljön och därmed stärka trädgårdsväxter att bättre motstå ett angrepp. Trädgårdsväxter som inte är typiska för skadedjuret att angripa kan förvilla dem genom att maskera värdväxtens lukt och därmed registrerar inte skadedjuret trädgårdsväxten. Utöver att maskera lukt kan vissa trädgårdsväxter även utsöndra flyktiga kemikalier som verkar motbjudande för skadedjuren och vara repellerande.

Validering av metoder för analys av Cu, Fe och Na i processvatten med AAS-grafitugn

Södra Cell Mörrum is one of the five paper pulp Plants that are included in Södra Cell, and the paper pulp that is produced here is not only sold to Swedish paper mills. Most of the paper pulp is exported to different countries in Europe. In the manufacturing process the plant needs different kind of process water and there are guideline values for how much copper, iron and sodium this water is allowed to contain. Analyzes of this water is in the current situation done with an atomic absorption spectrometric instrument (AAS-instrument) with a flame. Measurements done with flame-AAS of samples that have concentrations near the guideline values for copper, iron and sodium, are not reliable. The reason for not being reliable is that the quantitation limits of these metals are higher than the limit values.

Development of a method for determination of pesticide residues in honey using liquid chromatography tandem mass spectrometry

Honey is a product that may contain pesticide residues due to contamination from bees pollinating various Plants as well as elimination of vermin inside the hive. Different methods are needed for analysis of pesticides, since the term includes a wide range of different substances. National Food Administration lacks a validated method for determination and quantification of pesticides in honey using liquid chromatography tandem mass spectrometry, LC-MS/MS. The technique is especially important in analysis of polar and non-volatile pesticides, where gas chromatography is not functioning optimally. After investigating what pesticides could be found in honey produced in Sweden, a number of four pesticides suitable for analysis with LC-MS/MS was compiled; boscalid, impidacloprid, tau-fluvalinate and thiacloprid.

Kastanjemalen Cameraria ohridella : livscykel och utbredning i Sverige 2006

Cameraria ohridella, the chest-nut leaf miner, is a new pest in Sweden. These moths make leaf mines on chest-nut trees, preferably on Aesculus hippocastanum, which results in brown blotches on the foliage and early loss of leaves. Since the first observation in Macedonia in 1985 it has spread rapidly through Europe. The moth arrived in Sweden in 2003 when it was observed in Malmö and surrounding areas. In this paper a literature study describes the morphology and life cycle of the chest-nut leaf miner. Further more a test with pheromone traps examining the number of generations in Sweden is shown.

Differences in host plant preferences and olfactory physiology between populations of the moth Spodoptera littoralis established in Egypt and Benin

This study was made to compare and distinguish any differences in olfactory recognition and host plant adaptation between two strains of cotton leaf worm, Spodoptera littoralis. The populations used were established in Egypt and Benin, Africa. The documentation consisted of information about (1) each of the strains development through the larval stage up to pupation on diets of cotton, clover and cowpea. (2) Their oviposition preferences as adults between cotton, clover, cowpea, maize and cabbage. (3) Electroantennographic recordings to quantify any possible responses to plant volatiles. Throughout the diet experiments the larvae from the Benin strain showed significantly a better development between artificial, clover, cowpea and cotton respectively, while the Egypt strain had significance between artificial, cotton and cowpea/clover as diet. Also noted was how the strains substantial development of weight differentiated if fed the cotton diet, followed by the cowpea diet showing that the Benin strain would develop a higher body mass on a cotton diet as well as on a cowpea diet. This trend was however switched once the pupal stage was reached, where the Egyptian strain contained a significantly greater body mass than the Benin strain on the artificial and the Benin strain a greater on cowpea, which suggests that in the end, the Benin strain develops significantly better on cowpea while the Egypt strain develops better on an artificial diet. During the oviposition experiment that both stains showed a clear difference in hierarchy of host Plants considered suitable for oviposition, where the Egyptian strain is significantly more attracted to clover than the Benin strain. Also showed with electroantennographic recordings and significant values was the higher sensitivity the Egypt strain had towards (E)2-hexenal, (E/Z)-b-ocimene, (Z)-3-hexenyl acetate, Nonanal, (-)-linalool and ?-myrcene when compared to the responses from the Benin strain..

Effekt av sönderdelningsgrad och planteringsdjup på uppkomsten från rhizom av Tussilago farfara :

Tussilago farfara, coltsfoot, is a troublesome perennial weed with deep lying rhizome, which can vegetatively generate new Plants. The mechanical control of coltsfoot that is used today, "starvation", which consists of several cultivations of the soil, which fragmentises the rhizome. This results in production of new shoots, which leads to depletion of nutrient resources; as long the new plant is not allowed to establish. However, very little research has been done to investigate how the starving technique affects the regenerative ability of coltsfoot. The purpose of this experiment with coltsfoot was to investigate how fragmentation and burial depths affect the time of emergence, number of emerged shoots per rhizome fragment, number of shoots per node, and if the germination ability within nodes changes during the experiment.

Compost and its effects on soilborne plant pathogens

Certain microbial residents from composts are known to possess the ability to suppress soilborne plant pathogens. Trichoderma spp. and Gliocladium spp. are commonly found in composts and are perhaps the most wellknown hyperparasites of fungal pathogens, which may also be naturally present in compost. Trials have many times proven them to be effective against plant diseases caused by soilborne pathogens such as Pythium spp., Phytophthora spp.

Förstudie till våtmark i Rimbo : Design för optimal hydrologi och kväverening

The euthropthication of the Baltic Sea is a threat that is beginning to be taken seriously by the governments concerned. In Sweden, regulations concerning the allowed nitrogen (N) concentration in the effluent water from wastewater treatment Plants are being tightened up. The Rimbo wastewater treatment plant has been imposed to reduce the annual mean concentration of total N in the effluent water to levels below 15 mg l-1. A more and more common way to reduce the nitrogen level in wastewater is to let the water pass through a wetland. This study investigates the possibility to build this kind of wetland at the outlet of the Rimbo wastewater treatment plant.A prestudy of the topography, soil characteristics and groundwater flow indicates that the land area in question is well suited for the construction of a wetland.

Gullrisbock (Phytoecia nigricornis) i grus- och sandtäkter i Halland.

This dissertation is done as a preparatory step for the action plan of environmental protection shall issue to preserve the Phytoecia nigricornis in the country when it is red-listed and classified as vulnerable (VU). My task was to investigate the prevalence of the Phytoecia nigricornis in Halland County. They wanted to see if it existed in Halland (Ehnström, 1999). If it did not exist they wanted to know how to improve its habitat.the Phytoecia nigricornis is difficult to inventory because when it is larvae it lives in the roots and lower parts of the trunk of the Solidago Virgaurea plant and the adult beetles only keeps to Solidago Virgaurea by mating and egg laying and larval caterpillars when they hatch (Bily, 1989; Molander, 1999). Often it is overlooked or missed, and one question was whether it existed  in the whole country or only in those parts where it was previously found in, Skåne, Blekinge and Östergötland (Ehnström, 1999).One problem for the Phytoecia nigricornis is that their habitats is declining.

Utveckling av en beräkningsmodell för biogasproduktion

A growing interest for the climate and the environment has led to an increased interest forenvironmentally friendly and renewable energy sources, such as biogas. Planning new biogasPlants requires a decision basis including facts about approximate amounts of biogas possibleto produce at the plant. The purpose of this thesis is to develop a model that calculates theapproximate biogas and digestate production from a planned or existing biogas plant.Developing the model required a literature review and studies of calculations concerningbiogas and digestate production performed by WSP Sweden AB. As a complement to themodel development, facts about substrates for biogas production were compiled through aliterature review. In addition the methane potential from selected materials was determined bybatch experiments.

Optimerad styrning av kondensatorbatterier - Ny möjlighet att minska förluster med elektronisk brytteknik

Transmission of reactive power is well known to cause active power losses. Thus, newcomponents who can help minimizing these expensive reactive power flows are ofgreat interest to the power distribution companies. ABB Corporate Research hasdeveloped the first electronic power breaker. One possible application for thisbreaker is transient-free switching of capacitor banks. This could prove a usefuldistribution voltage complement to the switch-sync technique, mainly applied to transmissionvoltage level.

Utformning av hamnområdet i Arvika : stadsbild och offentliga miljöer

The harbour in Arvika is closed down and the industry that has been established in the area is now beeing wound up. A deepened comprehensive plan for the area is under progress in the municipality. The intentions are for instance that the harbour should be integrated with the city and that Arvika is facing a lake should be more apparent from the city center. The harbour should also contribute to a more attractive city. These intentions have hence been the starting point of my undergraduate theses, which has resulted in a proposal on how to develop the harbour. During the process I have analysed the city image, how the area is used today and the public places in the city centre.

Gröna upplevelser för alla : en trädgård för habilitering och återhämtning

Jällaskolans upper secondary School is situated on a big farm just outside Uppsala. The School is focused on agriculture, forestry, gardening, animal care and science. Jällaskolans staff has whished for a school garden for educational purpose where students can practice their gardening skills and learn more about Plants. But most important, a specially adapted outside environment such as a garden, would be a great advantage for the students with special needs. This garden could even be an asset for other visiting school classes in the region.

Teknik för egen foderberedning :

There is an uncertainty in the market for grain forcing the meat/milk producers to review alternative feeds to a larger extent, in order to get control over the feed costs. This has led to that the meat/milk producers need to have a good knowledge regarding how the different feeds influences the animals and which technical equipment to use for handling. For those that produce their own feedmix, there is a need to put interest in new crops and their characteristics to be able to get the knowledge of what is required for their own production. It is beneficial to keep an open dialogue with advisors to be updated in new crops and new technology for feeding. When mixing feed at farm level, the legislation is not very clear since it the target group is large scale mixing Plants. We have brought up the most important rules and regulations from the EU parliament Council as well as the ones from the Swedish Board of Agriculture (SJV), regarding feed mixing on farm and factory level. We have studied beans and pea at two different moisture levels, in order to evaluate how the moisture level affects the distribution of particles when milling with a plaitmill and a hammermill.

En uppföljning av floran i Enköpings vattenpark : kan anlagda våtmarker med vattenrening som huvudsyfte bidra till naturvård och biologisk mångfald?

Wetlands are important ecosystems and form habitat for both common and threatened species. In Sweden, as well in many other places on earth, there is a lack of wetlands. There is an expressed will to adjust this lack through restoration of wetlands with reduced function and through construction of new wetlands. Follow-ups and evaluations are important steps to optimize these actions. The wetland Vattenparken was constructed 1999 ? 2000 for treatment of surface water.

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