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50 Uppsatser om Pollen beetle - Sida 1 av 4

Molecular analysis of insecticide resistance in pollen beetle (Meligethes aeneus)

The escalating usage of pyrethroids has resulted in an increased awareness about resistance towards pyrethroids in insects. Pyrethroids inhibit voltage-sensitive sodium channels (VSSC) in nerve cell membranes and are composed of synthetic molecules based on pyrethrins present in pyrethrum extracts from Chrysanthemum species. VSSC are transmembrane proteins that are important for electric signalling over the membrane in insects. Mutations in the gene encoding the sodium channel have proved to be a common reason for resistance against pyrethroids. Pyrethroid resistance among Pollen beetles is spread all over Sweden and also abroad and is increasing.

Resistenta rapsbaggar :

Oilseed rape crops are an important in southern Sweden because of the high intensity of wheat growing. Pollen beetles are the most important pest in oilseed rape and causes often economic losses. Therefore it?s of great importance that we can control the population density, e g by using insecticides if necessary, to avoid mayor yield losses. In year 2000 Pollen beetles were numerous in the province of Östergötland. The farmers sprayed with insecticides several times, but with low effects on the beetles. Field trials and laboratory experiments showed that Pollen beetles had developed resistance against pyrethroids.

Faderskapsanalys av tallfrö från Västerhus fröplantage : Skillnad i pollenkontaminering mellan öppen pollinering och pollinering inom ett avgränsat system

In this study, pollen contamination (measured by the number of seeds pollinated by pollen not belonging to any of the clones on the seed orchard) is compared between open pollination and isolated pollination environments in a Scots pine (Pinus sylvestris) seed orchard called Västerhus, located outside Önsköldsvik. In this seed orchard a tent experiment is taking place. Skogforsk has built six large tents covering 12-14 trees with each tent. Fertilization patterns were compared between one tree in a tent with a supplementation of pollen from five clones not represented in the tent and another tree of the same clone subject to open pollination outside the tents. By using DNA markers the paternity was determined for 48 seeds from each tree.

Faderskapsanalys av tallfrö från Västerhus fröplantage : Skillnaden i pollenkontaminering mellan öppen pollinering och pollinering inom ett avgränsat system

In this study, pollen contamination (measured by the number of seeds pollinated by pollen not belonging to any of the clones on the seed orchard) is compared between open pollination and isolated pollination environments in a Scots pine (Pinus sylvestris) seed orchard called Västerhus, located outside Önsköldsvik. In this seed orchard a tent experiment is taking place. Skogforsk has built six large tents covering 12-14 trees with each tent. Fertilization patterns were compared between one tree in a tent with a supplementation of pollen from five clones not represented in the tent and another tree of the same clone subject to open pollination outside the tents. By using DNA markers the paternity was determined for 48 seeds from each tree.

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.

Människans roll i skogslandskapets trädslagssammansättning, en studie i Ångermanland

Human presence has always influenced the surrounding areas, the forest as well. Structure and species composition have changed during human land use. Knowledge regarding these changes should be of great interest for conservation and forestry. We have analyzed human impact on the tree species composition on five study sites during 2000 years in Ångermanland, Sweden. More specifically the change in tree species composition in percentage amongst alder, birch, spruce and pine over time.

Människan i urskogen : vegetationshistoria i Hamra nationalpark under 2500 år

Pollen analysis of a peat core was used to reconstruct the last 2500 years of vegetation history, with focus on the impact of anthropogenic disturbance, in Hamra National Park, central Sweden. In addition, analysis of pollen in soil samples was performed in an attempt to locate ancient cultivation plots in the National Park. The analysis of the peat core shows a development of the vegetation that can be divided into four stages of different degrees of human impact: A - virgin forest (c. 500 B.C.-A.D. 1300), B - grazed forest (c. A.D.

Är allergiförskolegården anpassad för barn med allergi eller annan överkänslighet för pollen? : En studie av den gröna miljön på två allergiförskolor.

Allergi är en av de vanligaste kroniska sjukdomarna hos barn i förskoleåldern och pollenallergi är den mest förekommande allergin. Syftet med examensarbetet var att se om den gröna miljön på två utvalda allergiförskolor i Stockholm var anpassad för brukargruppens behov. Beskriva förekomsten av växter på förskolegården som kan ge besvär för barn med allergi eller annan överkänslighet för pollen samt därtill ge förslag på åtgärder i den gröna miljön för att minska risken för växtrelaterade besvär.Slutsatser dragna utifrån empiri och teori visade att förskolegårdarnas gröna miljö inte var fullt anpassad för barn med allergi eller överkänslighet för pollen när det gäller växtlighet, pollenförekomst, utformning och skötsel. Utifrån resultatet kan flera möjliga orsaker till varför förskolegårdarna inte var helt anpassade för brukargruppen skönjas. Det visade på svårigheten att bedriva en verksamhet som i det här fallet en förskola för en speciell målgrupp utan att ha ansvar för planering och skötsel av förskolegårdens miljö.Då det framkom brister i den gröna miljön på förskolegårdarna föreslogs åtgärder för att minska riskerna för besvär orsakade av växtlighet.

Vegetationshistoria de senaste 5000 åren kring Fållnäs gård, Södermanland : med tyngdpunkt på antropogena aktiviteter

The manor Fållnäs gård is situated at the northern end of the bay Fållnäsviken, c. 12 km north-west of Nynäshamn, Sweden. A 300 cm long sediment core collected in the bay has been analyzed regarding pollen stratigraphy. AMS 14C dating of terrestrial macrofossils indicates that the sequence covers the last c. 5400 years.The aim has been to study vegetational changes, especially human impact, in the surroundings of Fållnäs gård.

Clear-cut and substrate characteristics important for the occurrence of the beetle Upis ceramboides

Disturbances, such as fire and wind, are important for saproxylic beetles (= beetles depending on decaying wood) to gain substrate in boreal forests. Clear-cutting is an example of a man-made disturbance. Measures such as prescribed burning have been made to resemble natural disturbances. The aim of this study was to see which clear-cut characteristics are important for the occurrence of the saproxylic beetle Upis ceramboides. This is a species favored by open habitats and is said to respond positively to forest fires. The distribution area in Sweden for this species has decreased during the last two centuries and I wanted to see if there were differences between clear-cuts in Hälsingland, where it is very rare and decreasing, and Norrbotten where this study was conducted.

Allergi påverkar det ett barns vistelse i förskola/skola? : Vilka kunskaper finns det idag angående barn och allergi?

Sammanfattning Barn drabbas i allt större utsträckning av allergi i någon form. Det är viktigt att forska kring dess medicinska verkningar på barnen och påverkan av allergin i det dagliga livet. Det forskas mycket idag kring barn och allergi. Läkarna ser en uppgång under senaste decennierna och ingen bättring i sikte. Det kan bero på dagens livsstil och miljötänkande.

Habitat preference and dispersal of a sandassociated beetle, Apalus bimaculatus

Species that have a high degree of specialization and poor dispersal ability can be more prone to extinction than more generalist species and good dispersers. How these species traits affect the viability of populations is dependent on landscape factors,such as isolation and connectivity. Additionally, interactions between species (e.g. symbiosis), and how these interactions vary spatially and temporally can have a large impact on populations. When the range and habitat areas of a species continuously decrease, management strategies are often needed if the species shall be able to survive.

Habitat preferences and reproductive success forthe threatened longhorn beetle Plagionotusdetritus

Plagionotus detritus is a threatend longhorn beetle that only exists at one site in Sweden. It is saproxylic and depending on recently dead coarse oak wood for its larval development. Trees at Djurgården, Stockholm that have been colonized by Plagionotus detritus has been studied to find out the habitat preferences of the species and to see what affects the density of beetles in a tree. The bark of some trees and wood from the breeding project at Nordens Ark has also been studied to find out what affects the species reproductive success. The reproductive success was measured in two ways, the larval mortality and the size of the hatching holes.

Bosättning, agrarkris och fäbodväsende : vegetations- och markanvändningshistoria i Läde, Dalarna

By using pollen analysis, 14C-dating and historical sources, I studied the history of vegetation and land use at an abandoned forest settlement near the Lade summer farms in the parish of Mora, Dalama. The aim of this paper is to investigate the agricultural establishment and development, the effects of this on forest vegetation, and the origin and development of summer farming. The analysis of pollen in a peat core revealed that a settlement was established at Lade around 1000 AD. Cereal cultivation, hay-making on the mire and extensive forest grazing were intro-duced as a complete agricultural system. Pollen analysis and the presence of ancient fields suggests that cultivation took place on permanent fields. Barley was the main crop, but rye and hops/hemp were also grown at the settlement.

Qualities and supply of suitable dead wood for Ceruchus chrysomelinus and its dispersal pattern in a translocated population

The wood-living beetle Ceruchus chrysomelinus is a rare species connected to natural forests. In Sweden, it is red-listed as endangered (EN) and an action plan for its preservation has been done by the Swedish Environmental Protection Agency. In this work I have therefore investigated how a translocation of the species succeeded after 17 years. I aimed to study the species dispersal biology, its substrate preferences and the supply of suitable wood on this site. The study was performed during 2012 in Pansaruddens nature reserve close to Uppsala in Sweden, which is a spruce dominated forest.

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