Thesis (doctoral)--Umeå Universitet, 1977. / Summaries in English and Swedish. Includes bibliographical references.

Thesis (Ph.D)-University of KwaZulu-Natal, Pietermaritzburg, 2008. / Full text also available online. Scroll down for electronic link.

Somatiska embryogenes är en mikroförökningsmetod som med hjälp av tillväxtreglerande medel får en växtdel att bilda skott och rötter i ett speciellt odlingssubstrat sterila förhållanden. Kunskapen vad gäller förutsättningar för groning och plantetablering efter detta laboratoriestudium är dock begränsad. I denna studie undersökte hur två kloner av SE-groddar av gran etablerade sig i olika ljusförhållanden avseende våglängd och intensitet i fyra växtmiljöer. Etableringen bedömdes utifrån plantornas överlevnad och höjdtillväxt. Vid sista inventeringstillfället var 62 SE-plantor vid liv och 18 plantor var döda. Ingen signifikant skillnad kunde påvisas i överlevnad mellan de olika växtmiljöerna, inte heller mellan klonerna i respektive miljö eller oberoende av miljö. Signifikant skillnad i höjdtillväxten mellan klonerna kunde påvisas inom alla växtmiljöer, men inte mellan växtmiljöerna oberoende av klon. Det fanns en tendens att ljusförhållanden med en ljusintensitet på 100 μmol och rött ljus inom våglängderna 610-760 nm gav bäst etablering för SE-groddarna. Studien visade också att det var skillnad i etablering mellan de två kloner som användes.

The Norway spruce Picea abies is an economically important export to the Swedish economy. There are a number of environmental and endogenous factors that impact the generation time of this species meaning that it can take 20-25 years for a tree to mature. The long generation time creates a challenge for plant breeding programs in terms of how genetic mechanisms are able to be studied as well as how quickly trees can be produced for lumber. The characterization of gene expression patterns in the context of special tissue domains is essential to understanding the underlying functions behind complex biological systems and in the case of P. abies may prove more crucial to determining the activation of genes at specific reproductive growth points. There are several techniques available for the analysis of spatial expression profiles, however, the unique high throughput nature coupled to the morphological information provided by Spatial Transcriptomics creates new opportunities for exploratory analysis. Spatial Transcriptomics offers a distinct approach to answering fundamental questions about the genetic mechanisms that regulate reproductive phase change and cone-setting in conifers. This study focuses on spatial gene expression analysis and the integration of de novo transcriptome assembly contigs to confirm the spatial context of putatively discovered genes such as DAL1, DAL2, DAL3, and DAL10 from previous studies and to potentially localize transcripts that could not previously be identified due to the inability to obtain complete transcripts. The aim is to create a workflow to identify genes that contribute to the growth patterns in the naturally occurring acrocona mutant that could prove useful to improving tree breeding programs.

Strategic management is crucial for organizational success in today's volatile business environment, and yet, underutilized within agricultural businesses. The agricultural industry is facing rapid change with the introduction of new GM technologies, such as CRISPR-Cas9, and following regulations. Although these technologies have the potential to provide farmers with improved crops containing desired traits, excessive regulations and obstacles hinder its implementation in European agricultural practices. If the upcoming decision regarding CRISPR-Cas9 allows the technology to not be treated under GMO regulations, European agriculture is faced with a major opportunity. However, as procedures are unexplored, organizations are left unprepared.   This study investigates the optimal strategic planning approach for Swedish agricultural businesses wanting to efficiently implement new technologies and adjust to regulatory changes. The research is based on a qualitative study that incorporates deductive methodology. It follows a multiple case study research design with eight semi-structured interviews from six Swedish and American case companies as the primary data collection method. By taking inspiration from experienced companies’ planning strategies and including European values, Swedish agricultural companies wanting to implement CRISPR-Cas9 can efficiently navigate changes within the industry while maintaining a competitive advantage. A simple model combining parts from short- and long-term planning frameworks with communication and value creation can guide companies entering the upcoming field.

Animal domestication, the process where animals become adapted to living in proximity to humans, is associated with the alteration of multiple traits, including decreased fearfulness and stress response. With an estimated population of 50 billion, the domesticated chicken is the most populous avian species in the world. Hundreds of chicken breeds have been developed for meat and egg production, hobby or research purposes. Multidirectional selection and the relaxation of natural selection in captivity have created immense phenotypic diversity amongst domesticates in a relatively short evolutionary time. The extensive phenotypic diversity, existence of the wild ancestor, and feasibility of intercrossing various breeds makes the chicken a suitable model animal for deciphering genetic determinants of complex traits such as stress response. We used chicken domestication as a model to gain insights about the mechanisms that regulate stress response in an avian species. We studied behavioural and physiological stress response in the ancestral Red Junglefowl and one of its domesticated progenies, White Leghorn. An advanced intercross between the aforementioned breeds was later used to map genetic loci underlying modification of stress response. The general pattern of the stress response in chickens was comparable with that reported in mammals, however we identified distinctive differences in the stress modulatory pathways in chickens. We showed that changes in the expression levels of several stress modulatory genes in the brain, the pituitary and the adrenal glands underlie the observed modified stress response in domesticated chickens. Using quantitative trait loci (QTL) mapping, several QTL underlying stress induced corticosterone, aldosterone and baseline dehydroepiandrosterone (DHEA) levels were detected. As a next step, we combined QTL mapping with gene expression (eQTL) mapping and narrowed two QTL down to the putative causal genes, SERPINA10 and PDE1C. Both of these genes were differentially expressed in the adrenal glands of White Leghorn and the Red Junglefowl, had overlapping eQTL with hormonal QTL, and their expression levels in the adrenal glands were correlated with plasma levels of corticosterone and al-dosterone. These two genes thus serve as strong candidates for further functional investigation concerning modification of the stress response during domestication. This dissertation increase the knowledge about genetics and physiology of the stress response in an avian species and its modification during domestication. Our findings expand the basic knowledge about the stress response in chicken, which can potentially be used to improve welfare through appropriate genetic selection.

Many previous studies in evolutionary genetics have been based on few model organisms that can be reared at ease in the laboratory. In contrast, genetic studies of non-model, natural populations are desirable as they provide a wider range of adaptive phenotypes throughout evolutionary timescales and allow a more realistic understanding of how natural selection drives adaptive evolution. This thesis represents an example of how modern genomic tools can be effectively used to study adaptation in natural populations. Atlantic herring is one of the world’s most numerous fish having multiple populations with phenotypic differences adapted to strikingly different environments. Our study demonstrated insignificant level of genetic drift in herring that resulted in minute genetic differences in the majority of the genome among these populations. In contrast, a small percentage of the loci showed striking genetic differentiation that were potentially under natural selection. We identified loci associated with adaptation to the Baltic Sea and with seasonal reproduction (spring- and autumn-spawning) and demonstrated that ecological adaptation in Atlantic herring is highly polygenic but controlled by a finite number of loci. The study of Darwin’s finches constitutes a breakthrough in characterizing their evolution. We identified two loci, ALX1 and HMGA2, which most likely are the two most prominent loci that contributed to beak diversification and thereby to expanded food utilization. These loci have played a key role in adaptive evolution of Darwin’s finches. Our study also demonstrated that interspecies gene flow played a significant role in the radiation of Darwin’s finches and some species have a mixed ancestry. This thesis also explored the genetic basis for the remarkable phenotypic differences between three male morphs in the ruff. Identification of two different versions of a 4.5 MB inversion in Satellites and Faeders that occurred about 4 million years ago revealed clues about the genetic foundation of male mating strategies in ruff. We highlighted two genes in the inverted region; HSD17B2 that affects metabolism of testosterone and MC1R that has a key role in regulating pigmentation, as the major loci associated with this adaptation.

No description available.

Jordbruket står inför många utmaningar. Grödorna behöver bland annat anpassas till ett förändrat klimat. Här är grödornas vilda släktingar, kulturväxtsläktingar viktiga, då de bär på stor genetisk variation. För att kulturväxtsläktingarna ska kunna användas i arbetet med att anpassa och utveckla dagens grödor är det av största vikt att de bevaras. Denna litteraturstudie syftar till att göra en kartläggning av bevarandearbetet som gjorts och behöver göras samt presentera Sveriges bevarandearbete. Litteraturstudien visar att flera internationella konventioner, bevarandestrategier och samarbeten har haft betydelse för bevarandearbetet. Vissa stora fröinsamlingsprojekt har gjorts och på vissa platser har skyddade områden för kulturväxtsläktingar upprättats. Dock krävs fortfarande ett omfattande bevarandearbete. Planer måste omsättas i praktiken, projekt finansieras och politiskt engagemang öka. I Sverige är arbetet på ett tidigt stadie, men vissa framsteg har gjorts och arbete pågår. Att öka kännedomen om kulturväxtsläktingar kan vara ett sätt att ge bevarandearbetet högre status och mer resurser. Där kan biologilärare göra en viktig insats genom att inkludera kulturväxtsläktingar och dess betydelse i undervisningen, till exempel att eleverna får arbeta med frågor om hur framtidens mattillgång kan säkras. / Agriculture is facing several great challenges. The crops need, among other things, to be adapted to a changing climate. Here, the wild relatives of the crops, the crop wild relatives, are important since they carry a vast amount of genetic diversity. For the crop wild relatives to be used in the process of adapting and improving today’s crops, it is essential that they are conserved. This literature review aims to make a survey of the previous conservation efforts and the work that remains, as well as presenting the conservation efforts in Sweden. The review shows that several international conventions, conservation strategies, and collaborations have been significant for the conservation efforts. Some large seed collecting projects have been completed and, in some places, protected areas for crop wild relatives have been established. However, extensive conservation efforts are still required. Plans need to be actualized, projects funded, and political incentive increased. The Swedish conservation efforts are still at an early stage, but some progress has been made and work is in ongoing. Increasing awareness about crop wild relatives could result in their conservation receiving a higher status and increased funds. Biology teachers can make an important contribution to this by including crop wild relatives and their significance in class, for example by letting students work with questions concerning the security of the futures food production.