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45 Uppsatser om Insects - Sida 3 av 3
Effect of Bacillus mediated priming on different natural genetic variants of Arabidopsis thaliana
In two feeding experiments Bacillus induced priming of plant defense was tested for its effect against the generalist insect pest Spodoptera littoralis. The main hypothesis for the study was that Bacillus induced priming would enable the plant Arabidopsis thaliana to defend itself
better against this insect herbivore since this priming seems to involve jasmonic acid, known to be important for plant defense to Insects. A secondary objective of the study was to examine if any differences in a primed defense capability could be seen between different natural genetic variants (ecotypes) of A. thaliana reflecting habitat differences in pest pressure.
The methods used for plant cultivation and Bacillus inoculation were aimed at reflecting conditions that can be expected in an agricultural cropping system. This meant that all plants were cultivated in soil, and the feeding experiments were conducted with the plants growing intact in the soil system.
Jätteträd ? inventering, bevaring, skötsel samt rekrytering :
During the summer of 2007 I was employed by Högestad Christinehofs Förvaltning AB. My
main task was to make an inventory of giant trees at the estate. Högestad and Christinehof,which with their total possession of 13 000 ha of land is the biggest estate in Scania.
A giant tree is a tree with a diameter in breast height more then 1 meter. Trees of these
dimensions are registered by Swedish authorities. Landowners with a giant tree on their
property can receive a subsidy for cutting trees that are in competition with the giant tree.(Levenskog, 2007)
Giant trees are important for biodiversity in the landscape and there are important habitats for different Insects, birds, bats, lichens and funguses.
Död ved i vatten - funktionella strukturer och dess påverkan på öring (Salmo trutta, L.)
The background to this work was to see if there was a connection between large woody debris (LWD) and the presence of brown trout in our Swedish forest streams. Previous researches by Degerman et al. (2004) have shown that there is a strong correlation between the amount of dead wood and the presence of brown trout. The goal was then to find a way to restore, maintain and increase the trout habitats by constructing and adding manmade wooden structures that would mimic natural deadwood and its features in flowing water. The inspiration was partially taken from a water restoration program in the Klamath River of northern California, USA.
Klimatfaktorers inverkan på granbarkborrens svärmningsintensitet i Medelpad
The spruce bark beetle (Ips typographhus) is one of the 25 000 species of Insects in Sweden, an insect of great economic importance because it can alone terminate forest of high value. During the past decade, insights of climate change received with increasing attention. If the future brings a milder climate in the north and therefore a longer growing season, one would think that it would only affect the forestry to the better? Yet in recent time, outbreaks after storm felling seems to occur more frequently. The Spruce bark beetle ruins millions of cubic meter of Norway spruce (Picea abies) in Sweden alone, with more frequent storm felling and a larger amount of wind thrown threes in the forests there will also be room for an advancing reproduction.
Trä som fasadmaterial ? behandling och beständighet
Since prehistoric time man has used wood to build their environment. The material?s availabilitycombined with its good mechanical properties has often made it the material of choice. Like allmaterials exposed to natures degradative processes the properties of wood decreases over time.Rot, UV radiation and attacks by Insects and pests damage wood if not protected. Since we wantwhat we build to consist, optimizing our building materials durability is of great interest.Techniques and methods for increasing the endurance of wood have been developed in severaldifferent places and for a long time.
Stabilisering av insektsangripna möbler : en jämförande studie av konsolidanter
Denna rapport är en jämförande studie av utvalda konsolidanter som används till att stabilisera nedbrutet insektsangripet trä. Av de trägnagande skadeinsekter vi har i Sverige är det främst den strimmiga trägnagaren som är intressant i möbelsammanhang. I rapporten beskrivs den strimmiga trägnagaren, en liten skadeinsekt som kan åstadkomma stor skada om den får verka ostörd. Insekten finns utspridd i hela Europa och är ett stort problem då den angriper alla typer av träslag. Nedbrutet insektsangripet trä förlorar sin styrka och kan behöva konsolideras genom att injicera konsolidanter in i träet.
Bruka utan att förbruka - när andra intressen än ekonomin får styra
To have a forest area close to the city is of great importance for the city population?s well being. Children develop their motor skills, concentration and imagina-tion and the adults have a place to shake of the stress from work. Forest areas are used to exercise at, play in and to find a moment of peace and silence.
The urban forest and the old farming pastures at Markussonvallen and Per-Isakssonvallen already has natural assets worth to preserve and a great potential to create more. The goal is to develop a forest with a variation of tree species and ground vegetation that will appeal to the human senses and different animal species such as birds, Insects etc.
137Cesium i myrsamhällen i Gävleborgs län 24 årefter Tjernobylolyckan
24 years have passed since the Chernobyl accident when radionuclides were spread over largeareas of Europe, including the Scandinavian countries. Today, measurable activities of 137Csare still observed in many Swedish ecosystems.Ants (belonging to the order Hymenoptera) are social Insects which collect organic materialfrom a large area around their nests. This study focuses on the 137Cs activity in ant nests andthe cesium accumulation in these nests. The aims were (1) to estimate the 137Cs fall-out in1986, (2) estimate the radiation exposure of ants and (3) find how 137Cs is distributed in an anthill. Seven ant hills (occupied by the species Formica polyctena) were studied near the villageof Hille, situated north of the city of Gävle in central Sweden.
The effect of domestication on insect resistance in cotton : bioassays with the insect herbivores Spodoptera littoralis and Agriotes spp.
A plant's defensive ability against herbivore attack can be influenced by many different factors, one of them being domestication. During human selection to improve the yield of plants, the resistance against herbivore attack can have been lowered, due to a trade-off for use of resources between these traits in the plants.
In this thesis I investigated the effect of domestication on resistance against herbivorous Insects in cotton plants. I used different varieties and species of wild and domesticated cotton in three different experiments. A feeding assay was conducted, the mortality, development
time and pupal weight of larvae of the Egyptian cotton leaf worm Spodoptera littoralis was studied. In a second experiment the preference of the root-feeding beetle Agriotes spp.
Insekter i hårt törskateangripna ungtallbestånd i Norrbotten : skadeinventering och artbestämning
Sedan i början av 2000-talet har nordligaste Sverige drabbats hårt av törskateangrepp och det är konstaterat att skadorna framförallt har orsakats av den värdväxlande varianten C. flaccidum. I Sverige visade forskning i början av 1900-talet att flera arter från fjärilssläktet Dioryctria (barrskogsmott) förekom i samband med törskateskador. Med de stora törskateskador som idag finns i norra Sverige är det fortsatt intressant att ta reda på vilka arter som idag kan påträffas och vilken roll de kan spela vid dessa skador.
Syftet med studien har varit att, genom en fältstudie, bedöma förekomst och omfattning av angrepp från barrskogsmott och törskatesvamp i ett urval på 18 bestånd.
Syftet var också att, med en kontrollgrupp genom en förkortad kläckningsprocess, försöka artbestämma barrskogsmotten som angripit träden samt att försöka bedöma hur vanligt det kan vara att insektsangrepp inte upptäcks i fält.
Utveckling i Ammerån : att skapa ett hållbart fiske med hög kvalitet
Ammerån which is a small forest river in eastern Jämtland is a well-known river that has been a popular fishing river for a long time. The actual Ammerån begins downstream the lake Solbergsvattnet at Hammerdal and flows into the Indalsälven 10 km upstream Hammarstrand. The river environment switches between forests with wilderness feeling and open agricultural land. The entire Ammerån is today a nature reserve and protected from hydropower development. Fishing in Ammerån has mainly been focused on trout and grayling, and is so even today.
A screening for Schmallenberg virus among sheep, goats and cattle in Zambezia province, Moçambique : and preparations for a metagenomic survey of virus in mosquitoes
As the world´s population increases and people's living conditions are improving, larger areas are needed for houses as well as food production. This means that
new areas are exploited and that people, livestock, blood sucking Insects and wild animals are forced to live close together. In combination with the global warming,
leading to extreme weather such as floods and storms, this allows both new and old pathogens to emerge. The number of "emerging infectious diseases", EIDs, has increased in recent years and many of them have their origin in poor, tropical countries. Moçambique is therefore considered to be a high risk area for EIDs.
Schmallenberg virus, SBV, was discovered in 2011 as an "emerging infectious disease" in dairy cows in Germany.
Rumslig fördelning av grov gammal tall i Uppsala stad med tallticka som indikator på höga naturvärden :
Fragmentation and reduction of forest area is a threat for many forest species and their habitat. Deficiencies in forest quality, such as lack of dead wood and old trees, are one explanation of the threat. The most important action to prevent the continued loss of forest types is to protect forest, but also to restore and to create areas that not previously had high nature values. Hence one of the key strategic roles for Fritid- och Naturkontoret, Uppsala municipality, is to monitor biodiversity in the context of urban planning.
The majority of the Uppsala municipality residents live in urban areas and most of them spend some of their spare time in natural areas in cities and their immediate surroundings. Exploitation in and around Uppsala is high, but it is important that there is enough nature close to houses to meet the residents? needs of recreation.
Power Lines - Wasteland or Biodiversity Hotspots?
Det svenska kulturlandskapet har förändrats radikalt under de senaste 200 åren från ett varierat och heterogent landskap till ett mer monotont, homogeniserat landskap som följd av att olika former av mänskligt resursutnyttjande har effektiviserats. Detta har lett till en fragmentering av livsmiljöerna för flera av kulturlandskapets arter. Kraftledningsgator kan tänkas hysa naturtyper som påminner om vissa av de nu försvunna eller fragmenterade livsmiljöerna (t ex betad skogsmark och vissa typer av ängsmarker) och skulle kunna ha en viktig betydelse som reträttplats och/eller spridningskorridor för dessa arter.I en fallfällsinventering i Köpings och Strängnäs kommun i Mälardalen undersöktes förekomst och abundans av marklevande evertebrater i kraftledningsgator, skog och betesmark. Jämförelser i förekomst och abundans gjordes mellan dessa marktyper (d v s kraftledningsgator, skog och betesmark), samt mellan positioner inom kraftledningsgator (centrala och distala delar) och närliggande skogsmark. Jämförelserna innefattade dels analyser av artantal (eller snarare antal taxa) och flera olika biodiversitetsindex och dels analyser av likhet i artförekomst och individantal med "likhetsindex" (similarity index).
Odlingens och lagringens inverkan på utsädes grobarhet :
At seed-growing the aim is to produce a commodity with high germination capacity, good soundness
and purity, and also slight admixture of seeds from other species. The capacity of germination and the
vigour of the seeds may become impaired in consequence of mechanical damage, infection of diseases,
growth of mould, attacks of vermin, high drying temperature, secret germination, sprouting in the ears
etc. The germ belongs to the outer and most unprotected parts of the seed, and consequently this is
much exposed. Even quite sound seeds can instantaneously have low capability of germination. It can
be due to the fact that the seeds are in rest of germination, i.e.