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1
Gale, Samantha. "The cryopreservation of Picea sitchensis germplasm." Thesis, Abertay University, 2005. https://rke.abertay.ac.uk/en/studentTheses/460ff7ff-fbd6-4e9b-93dd-addb29b13c77.
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Picea sitchensis is an important tree species for UK forestry and is at the forefront of prototype clonal breeding programs. These can only be implemented using in vitro, culture therefore cryopreservation technology development is imperative such that elite germplasm can be conserved, without compromise to genetic integrity, whilst phenotypic validation of selected genotypes is undertaken. Three explant types were transferred from the Northern Research station, Roslin to the University of Abertay, Dundee where cryopreservation testing was initiated. Each explant comprised of different anatomical complexities varying from the simplest dedifferentiated embryogenic suspensor masses, to matured somatic embryos and whole tissue shoot-tip apices. Before cryopreservation was initiated in vitro cultures were stabilised and characterised at UAD. Shoot cultures showed different growth responses between genotypes and between culture locations, but biochemical profiling of oxidative stress markers, ethylene and DNA methylation did not confirm stress or epigenetic change as the cause of these differences and physiological recalcitrance. A cryopreservation protocol, using a programmable freezer (Planar), was successfully developed and is reported for the first time for P. sitchensis embryogenic suspensor masses (ESM). Post-LN survival rates of up to 100% were observed in several genotypes. Encapsulation-dehydration was successfully utilised to cryopreserve P. sitchensis mature somatic embryos reported for the first time. Recovered embryos were able to re-initiate into dedifferentiated non-embryogenic masses (NEM) (up to 100%) and embryogenic suspensor masses (ESM) (up to 20% post -LN) as a source of material to mass multiply cryopreserved clonal offspring. Major steps were progressed for the most recalcitrant conifer explant in the project, shoot-tip apices, with essential pre-treatment steps established. Critical cryogenic factors were determined through thermal analysis using Differential Scanning Calorimetry. The study concluded with the initiation of technology transfer of cryopreservation methods to the Northern Research Station to establish the UK’s first conifer cryobank. These systems were preliminary validated. Further implementation will proceed out with the timescale of this project but based on recommendations generated from this thesis.
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Franckaitytė, Lina. "Nevietinių eglės rūšių produktyvumas, kokybė ir tinkamumas plantaciniams želdiniams." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2010. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2010~D_20100621_113024-14958.
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Magistro darbe tiriama galimybė veisti plantacinius želdinius iš svetimžemių eglių rūšių greitam medienos išauginimui Lietuvoje.
Darbo tikslas – įvertinti sitkinės eglės (Picea sitchensis), baltosios eglės var. alberta (Picea gauca var. albertiana), raudonosios eglės (Picea rubens), ajaninės eglės (Picea jezoensis), tarprūšinių hibridų – paprastoji eglė x kanadinė eglė (Picea abies x Picea glauca), paprastoji eglė x baltoji eglė (Picea abies x Picea glauca var. albertiana) genotipų tinkamumą sutrumpintos rotacijos plantaciniams želdiniams.
Darbo objektas – Rokų Kelmyno bandomieji želdiniai.
Darbo metodai ir techninės priemonės – tyrimo metu buvo įvertinti medžių kokybiniai ir kiekybiniai požymiai bandomuosiuose želdiniuose naudojant tokius prietaisus ir metodus: aukštis - aukštimačiu, skersmuo – žerglėmis, kokybiniai požymiai buvo įvertinti pagal vizualaus medžių kokybinių požymių įvertinimo metodiką. Taip pat buvo atlikta šių duomenų statistinė analizė. Naudoti tokie metodai: aprašomosios statistikos rodiklių palyginimas ir tiesinė koreliacinė analizė.
Darbo rezultatai. Picea sitchensis ir abu tarprūšiniai hibridai pasižymi didesniu skersmeniu ir aukščiu, taip pat didesniu tūriu, nei vietinė paprastoji eglė. 33 metų amžiuje Picea sitchensis produkuoja 540 m3/ha medienos, kas rodo jos tinkamumą trumpos apyvartos želdiniams. Picea glauda var. albertiana, Picea jezoensis, ir Picea rubens produktyvumas yra mažesnis nei Picea abies. Didžiausiu tiesių ir vienastiebių... [toliau žr. visą tekstą]This master thesis analyses possibility to cultivate exotic spruce plantations for shorten rotation forestry in Lithuania. Objective of the study was to find out suitability of Picea sitchensis, P. gauca var. albertiana, P. rubens, P. jezoensis, P. abies x P. glauca, P. abies x P. glauca (var. albertiana) for shorten rotation plantations. Object – Roku Kelmyno experimental forest area. Methods – such qualitative and quantitative tree parameters as height, diameter were assessed using clinometer and callipers. Qualitative parameters were assessed using visual tree qualitative parameters assessment methodics. All data was statistically analyzed. Methods used: comparison of descriptive statistics parameters and linear correlation analyzes. The results – Picea sitchensis and both interspecific hybrids have bigger diameter, height and volume parameters than local Norway spruce. Picea sitchensis produce 540 m3/ha of timber in 33 years, it shows suitability for shorten rotation plantations. Productivity of Picea glauda var. albertiana, Picea jezoensis, and Picea rubens is poor compared to Picea abies. Biggest percentage of straight and single-stemed trees were noticed in sitka spruce and both hybrids stands. Yezo spruce had the smallest percentage (62%) of healthy trees. Whereas the other tree species had percentage of healthy trees between 80 and 95. Branches positioned by blunt angle according the steam dominated in all stands and percentage of such trees was from 88 to 100. P... [to full text]
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Selby, Christopher. "Micropropagation of Sitka spruce : (Picea sitchensis (Bong.) Carr.)." Thesis, Queen's University Belfast, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356923.
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Kennedy, Stuart G. "Improving the wood strength of Sitka spruce (Picea sitchensis) through selective breeding." Thesis, University of Aberdeen, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=103124.
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Tree breeders worldwide have highlighted the importance of wood quality within the juvenile core in determining final timber strength. The potential for improving timber strength by estimating genetic parameters of certain wood properties of Sitka spruce (Picea sitchensis) within the outer zone of the juvenile core was investigated. Fifteen trees were sampled from each of 33 families selected from a 20 year old open pollinated progeny trial. A number of wood properties critical to wood strength were measured; namely, density, grain angle, microfibril angle and branching characteristics. Clearwood stiffness and strength along with indirect measures of stiffness using acoustics and density using Pilodyn measurements were assessed. All wood properties were moderately heritable, wood density and acoustic velocity were the most heritable traits (h2 i 0.71 and 0.67 respectively). Genetic correlations showed that wood strength and stiffness were strongly correlated with wood density (0.86 and 1.04 respectively) and microfibril angle (-0.79 and -0.62 respectively). Acoustic velocity was strongly correlated with wood stiffness (0.81) and microfibril angle (- 0.83). The ability to select trees for wood stiffness with the use of acoustics along with the moderate inheritance of this trait should enable improvements in the wood quality of Sitka spruce. Despite the unfavourable correlation between growth rate and some key wood quality traits associated with timber strength, selection of certain families would enable modest gains to be made in both growth rate and wood quality.
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Drake, Pascal M. W. "Approaches to the genetic transformation of Sitka spruce (Picea sitchensis)." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320788.
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Holliday, Jason A. "Genomics of adaptation to local climate in Sitka spruce (Picea sitchensis)." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/6729.
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Genecological studies in widely distributed tree species have revealed steep genetic clines along environmental gradients for traits related to adaptation to local climate. In the face of a changing climate, the ecological and economic importance of conifers necessitates an appraisal of how molecular genetic variation shapes quantitative trait variation. I have combined transcript profiling with association mapping to better understand the genomic architecture of adaptation to local climate in conifers, using Sitka spruce (Picea sitchensis) as a model. A microarray study during the fall hardening period revealed wholesale remodeling of the transcriptome within a population originating in the centre of the species range, and substantial variation in the autumn transcriptome was observed when populations from the northern and southern limits of the range were compared. Based on these data, a suite of candidate genes was selected and screened for single nucleotide polymorphisms (SNPs) in a panel of 24 individuals. A diverse array of biological processes were represented among the candidate genes, including stress response, carbohydrate, lipid and phenylpropanoid metabolism, light signal transduction, and transcriptional and posttranscriptional regulation. Nucleotide diversity in Sitka spruce was approximately average for a conifer (π = 3.49 x 10⁻³), and linkage disequilibrium decayed rapidly. Tests of selective neutrality suggest widespread purifying selection within these candidate genes, though evidence for positive selection was detected within a few. In addition, I observed evidence for diversifying selection in 8% of the studied genes, which exhibited high population differentiation relative to the genome-wide average FST of 0.12. To identify genetic determinants of phenotypic variation in locally adaptive traits, an Illumina GoldenGate assay was used to genotype 768 SNPs in a mapping population comprised of 410 individuals from 12 geographical populations collected from across the species range. After correcting for population structure and relative kinship, associations were detected in 28 of the candidate genes, which cumulatively explained 28% and 34% of the phenotypic variance in cold hardiness and budset, respectively. Most notable among these associations were five genes putatively involved in light signal transduction, the key pathway regulating autumn growth cessation in perennials. This study represents a significant step toward the goal of characterizing the genomic underpinnings of adaptation to local climate in conifers, and provides a substantial resource for breeding and conservation genetics in a changing climate.
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Weatherhead, I. "Causes of graft failure in Sitka spruce, Picea sitchensis (Bong.) Carr." Thesis, University of Reading, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374703.
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Page, Louise McBean. "Natural regeneration of Sitka spruce (Picea sitchensis (Bong.) Carr.) under partial canopy." Thesis, University of Aberdeen, 2002. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU181384.
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This study set out to explore the relationships between overstorey canopy and regeneration with a view to recommending silvicultural prescriptions for transforming even-aged Sitka spruce stands to uneven-aged (irregular) stands and managing such stands. An experiment was established in Kingdrogan Forest, Perthshire in which six small (20 m diameter) circular gaps were created in a stand of 32 year olds Sitka spruce. Eight plots were established along a north south transect through the gap and which extended under the canopy on either side of the gap. Four plots were in the gap, two under the canopy north of the gap and two under the canopy south of the gap. Each plot contained three sub-plots which contained the following treatments: planting of Sitka spruce nursery grown transplants, artificial seeding and control. Germination, survival and growth of seedlings were monitored over subsequent growing seasons. Environmental monitoring was carried out for two years: namely canopy openness, temperature and soil moisture. Germination rates were fond to be highest in the light shade in the southern half of the gap although growth was highest in the sunny northern half of the gap. Almost no seedlings survived under the canopy. A complementary survey of older advance regeneration was carried out on two sites, Comlongan Forest in southwest Scotland and Tarenig in mid Wales. The survey looked at canopy density, characterised by canopy openness and basal area, and density and growth of natural regeneration. Canopy openness and basal area were not found to be significantly related. Basal area was a better indicator of both regeneration density and growth than canopy openness. It appeared that in order to encourage growth of the natural regeneration the stand should be kept at a basal area of 30m2ha-1 or less. This is less than the value (38m2ha -1) for a fully stocked stand. Tentative recommendations are made for the transformation of regular, even-aged stands of Sitka spruce into irregular stands.
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Meehan, Eamonn James. "Sitka spruce (Picea sitchensis (Bong.) Carr.) propagation technologies : their effects on genetic diversity." Thesis, Queen's University Belfast, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486558.
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The aim of this smdy v,'as to assess the genetic diversity of Sitka spruce seedling populations as produced by commercial growers and to detennine what effects the propagation technologies ofrooted cuttings and somatic embryogenesis had on genetic diversity. Seedling populations ,,,ere produced consisting of one hundred seedlings' from each of three families of Washington provenance material and from each of three families of Queen Charlotte Islands provenance. Rooted cutting populations were produced from twelve cuttings from each of fifty randomly selected plants [rom each of the six families. Somatic embryogenesis derived populations (emblings) were produced and fifty populations were provided by Coillte from the three Washington provenance families which represented the maximum number of cell lines produced by a successful commercial grower. Significant phenotypical differences betwe.en zygotic seedlings were found at both family and provenance level after 19 months of grov.1h. All 300 genotypes were able to produce rooted cuttings indicating that no significant loss of genetic diversity in cuttings from two-year-old trees. Seven pairs of microsatellite primers were multiplexed to amplify polymorphic microsatellite DNA loci from needle samples of seedlings and emblings. Capillary electrophoresis of the products yielded data which were analysed according to the Infinite Allele Model and Stepwise Mutation Model. No significant differences were found, using either mutation model, between the genetic diversity values (observed heterozygosity, gene diversity, allelic richness and inbreeding coefficient (Fis)) for the seedling populations and somatic embryogenesis derived populations. A low level of microsatellite variation was found to occur within mature individual trees and within somatic embryogenesis derived populations. The extent of microsatellite variation was found to be dependent on locus and genotype. The propagation technologies of somatic embryogenesis and rooted cuttings do not cause a loss of genetic diversity in the resulting populations.
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Hamilton, Jill Adelle. "Genomic and phenotypic architecture of a spruce hybrid zone (Picea sitchensis x P. glauca)." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43001.
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Natural hybrid zones may be viewed as important biological systems for examining the role of selection in creating and maintaining species differences. Where ecological differences exist between hybridizing species, these zones may provide useful insight into the genetic architecture of important traits involved in adaptation. I have evaluated the genomic and phenotypic architecture of the economically and ecologically important Picea sitchensis (Sitka spruce) x P. glauca (white spruce) hybrid zone along the Nass and Skeena river valleys in northwestern British Columbia using chloroplast and mitochondrial markers, twelve microsatellite loci (SSRs), and 268 single nucleotide polymorphisms (SNPs), in combination with morphological variation, and phenotypic data from a common garden. Maternally- and paternally-inherited organelle markers, in combination with bi-parentally inherited nuclear markers, were used to estimate both the historic and contemporary direction and extent of gene flow within the hybrid zone. Sitka spruce mitotype ‘capture’ throughout the introgression zone point towards asymmetric gene flow, congruent with microsatellites and SNPs, indicating extensive long-term introgression and widespread recombination with more Sitka spruce than white spruce ancestry in hybrid populations. Significant clinal variation was observed for marker-based hybrid indices and morphological traits associated with climate and geography, while growth and cold hardiness traits evaluated in a common garden exhibited weak to non-significant clines. These results indicate extrinsic selection appears to play a strong role in the distribution and structure of this hybrid zone, which fits expectations for the environmentally-determined bounded hybrid superiority model of hybrid zone maintenance. However, intrinsic mechanisms of hybrid zone maintenance could not be ruled out. Finally, broad-scale patterns of variation, combined with fine-scale analysis of candidate SNP-specific patterns of introgression revealed a suite of candidate loci that may be targets of extrinsic or intrinsic selection. These loci may be involved in either adaptation to climate across the zone, particularly precipitation gradients, or involved in the maintenance of species barriers. These results have important implications for genetic conservation of adaptive variation, selection of seed sources for current reforestation within this ecologically transitional area, and appropriate scale and direction of seed transfer relating current genotype-climate associations to future climate predictions for this region.
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Hayward, Sean. "Measurement and evaluation of volatile organic compound emissions from Sitka spruce (Picea sitchensis Bong.)." Thesis, Lancaster University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404227.
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Armstrong, Janet A. "Ion exchange across the surface of the foliage of sitka spruce (Picea sitchensis (Bong.) Carr.)." Thesis, University of Aberdeen, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357957.
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Two series of experiments have been carried out to study the relative contributions of both dry deposition wash off and crown leaching, including H+ -cation exchange, to the change in chemistry of rain passing over the leaves of Sitka spruce (Picea sitchensis (Bong.) Carr.). In the first experiments detached needles and small trees were washed under several conditions with artificial acid rain water, following various pretreatments. Increases in Na and Mg in the canopy drip were found to be due, predominantly, to washed off dry deposition whereas about 50% of the K and Ca increases on washing with solutions of pH less than 4 were considered to be due to leaching of neutral salts and H+ -cation exchange. In a second series of experiments the unidirectional membrane fluxes of ions across the needle surface were studied by compartmental analysis, using 36Cl, 45Ca and 42K. There appears to be a net loss of all these elements when artificial rain water solution of pH 4.3 was used for elution. Neutral salt leaching over 24 h may result in as much as 5% of total K present in needle being lost, making it the most readily leached cation. Ca is not readily available for exchange as it is bound within the vacuole and cell wall. It was determined that about 15% of total Ca is available for exchange, of which 1.5-3% is considered to be leached as neutral salts. The elution of 45Ca from needles attached to twigs suggested that leached Ca may be readily replaced by movement from the translocation stream to the cytoplasm. Although Cl in canopy drip is generally considered to be due predominantly to washed off dry deposition, about 12.5% of the total Cl content of needles was estimated to be leached over 24 h.
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Palmer, Imogen Patricia. "Edge-effects in canopy arthropods of Picea sitchensis and Pinus sylvestris plantations in the UK." Thesis, University of Surrey, 1999. http://epubs.surrey.ac.uk/848504/.
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The present research aims to establish the depth of abiotic and invertebrate edge-effects occurring in plantations of two conifer species, and the resulting effects of management practices on 'edge' and 'core' invertebrate communities. Near complete invertebrate samples were collected using chemical knockdown allowing analysis of invertebrates at the order, family, genus, species and guild level. Similar invertebrate densities per m[2] ground area occurred in both tree species, although communities differed between them, Pinus sylvestris supporting a more diverse community than Picea sitchensis. Species richness, diversity and densities varied with distance from plantation edge with the Acarina, Araneae, Coleoptera, Collembola, Diptera and Hemiptera showing particularly strong responses to edge proximity. Abiotic edge-effects, although variable between transects, occurred to an average depth of 30 metres with an approximate 1 C drop in temperature and a 5% increase in relative humidity towards the core. Invertebrate edge-effect depths varied with species, ranging from 5 to 80 metres. In P. sitchensis invertebrate richness and densities, particularly for Coleoptera, Araneae and Hemiptera were higher in the edge habitat, whilst increased richness and diversity occurred in the core of P. sylvestris. Edge habitat is key to optimising richness in P. sitchensis, however application of core-area models shows that current plantation management fails to maximise edge habitat. Reduction of patch size and/or increasing edge features will increase species richness. In contrast core habitat is vital to species richness in P. sylvestris. Current small patch size limits invertebrate richness, increased patch size and implementation of edge buffer zones would protect core habitat thus enhancing invertebrate species richness.
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Lobo, Nina L. "Clinal variation at putatively adaptive polymorphisms in mature populations of Sitka spruce (Picea sitchensis (Bong.) Carr.)." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/34558.
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Common garden experiments in widely distributed tree species have demonstrated that phenotypic traits timing of bud set exhibit clinal variation across provenance climatic and geographic gradients, emphasizing the importance of these traits in local adaptation. With rapid advances in molecular techniques, spatial patterns of genomic variation underlying these traits can also be studied. Here I assess whether 17 putatively adaptive single nucleotide polymorphisms (SNPs) previously shown to be statistically associated with cold adaptation phenotypes vary clinally along a temperature gradient in natural, mature populations of Sitka spruce (Picea sitchensis). I also test the hypothesis that clinal strength is stronger in mature spruce populations than in seedling populations due to selection.
Regressions were run for each of the 17 SNPs with logit-transformed major allele frequency as the dependent variable and provenance mean annual temperature (MAT) as the independent variable. Next, differences in strength of clines between mature and seedling populations were estimated for each SNP separately and for the 17 SNPs as a group. Finally, I ran two alternate analyses – a full analysis that included all seedling populations and a truncated analysis that limited the range of MAT observed in seedling populations to match that of mature populations.
My results vary between the full and truncated analyses. In seedlings, the full analysis revealed clines in 11 SNPs (65%) compared to six SNPs (35%) in the truncated analysis. Mature populations had significant clines for five SNPs (29%). For the full analysis, the group test supported the one-sided hypothesis that mature populations have significantly steeper clines than seedlings across SNPs (P=0.027).
Parallel clines in seedling and mature populations were observed for a subset of the SNPs, which strengthens their importance for local adaptation. However, low power limited my ability to make conclusive statements about differences in clinal strength between mature and seedling populations. While most SNPs were present in most populations, I also observed that the northern, disjunct population of Kodiak Island, AK was fixed for the highest proportion of SNPs (59%). This suggests that this recently founded population may lack adaptive diversity to respond to rapid climate change in the future.
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Major, Elizabeth Jane. "Environment and genotype effects on the resistance of Picea sitchensis (Bong.) Carr. to Elatobium abietinum (Walk.)." Thesis, Bangor University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257658.
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Vihermaa, Leena. "Influence of site factors and climate on timber properties of Sitka spruce (Picea sitchensis (Bong.) Carr.)." Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/2271/.
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In plantation grown Sitka spruce, timber density is an important quality concern. Currently Sitka spruce timber meets the requirements for C16 strength grading which is the minimum requirement for construction uses. However, the margin is not exceeded by much and a small reduction in density could lower the log grading. Therefore it is essential to understand how timber density is impacted by site factors and climate in order to predict the potential effects of climate change on timber quality in Sitka spruce in the future. This has important economic implications for UK forestry. To assess the influence of site factors and climate on growth and resulting timber properties in Sitka spruce, three experiments were established; a large scale wood quality survey (“The Benchmarking experiment”), a detailed inter-site density study (“The Level II experiment”) and a continuous growth monitoring experiment (Dendrometer experiment). In the ‘Benchmarking’ experiment, increment cores were collected from 68 sites over a geographically wide area in Scotland and Northern England in order to quantify the effect of selected site factors on density. These samples were not suited for climate analysis at annual ring level and therefore disks that allowed reliable dating of the tree rings were collected from three Level II sites. The Level II samples were also used in an acoustic velocity study and an assessment of the within-tree patterns in density. Material from both Benchmarking and Level II sites was used for modelling radial density. In addition to this the Level II data functioned as a test dataset for the different density models that were developed on the Benchmarking data. Density and other tree ring variables were measured with an ITRAX X-ray densitometer and WinDENDRO software. Some acoustic measurements were also carried out with a purpose built ultrasonic scanner to allow calculation of radial variation in stiffness. A dendrometer experiment was established to monitor short term growth variation in Sitka spruce in real time. The aim was also to use the growth data to date density profiles and hence identify causes for the density differences. Data analysis was carried out in R mainly using linear and non-linear mixed effects models, the dendrochronology software package dplR and methods of time series analysis. It was found that the largest part of the variation in density was between trees within each site. Both density and stiffness were mostly influenced by the growth rate or by another variable describing the tree vigour. Fast growth decreased density both by increasing earlywood proportion as well as decreasing the density of both earlywood and latewood. Models for the radial behaviour of density and stiffness could be fitted to the data, but random tree effects remained large. This limits the applicability of these models to new sites as reparameterisation would be required, which requires data from time consuming density and acoustic velocity measurements. The possibility of modelling the model coefficients from easily measurable stand and tree variables was investigated but the results were not promising. The Dendrometer experiment indicated that annual growth in Sitka spruce was initiated in late May and terminated by mid September. Ring widths detected by the dendrometers, micro core measurements and X-ray density based tree ring analysis differed, which caused difficulties in dating the density profile. To decrease these problems in the future the microcore sample storage protocol was revised. The dendrometer data indicated that the growing season was divided into several sections between which the growth rate differed. Latewood density and maximum density had the strongest correlations with the climatic variables. At one site the correlations included temperature and rainfall in April whereas at the other precipitation throughout the growing season or during the May-August period were important. Temperature was correlated positively with density variables and rainfall negatively.
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Jones, Stephen Keith. "Sitka spruce (Picea sitchensis [Bong.] Carr.) seed germination in relation to seed development, dormancy and storage." Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283746.
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Miller, Helen. "The effect of heat on graft union formation in dormant Sitka spruce (Picea sitchensis (Bong.) Carr.)." Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306468.
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Drewitt, Hannah J. "Genotypic and environmental variability in the growth and photosynthesis of Sitka spruce (Picea sitchensis [Bong.] Carr.)." Thesis, Durham University, 2005. http://etheses.dur.ac.uk/2840/.
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In 1990, clonal seedlings from twelve full-sib families of Sitka spruce (Picea sitchensis (Bong.) Carr.) were planted at four contrasting sites throughout the UK; Newcastleton and Wauchope in the Scottish Borders; Scootmore m Morayshire; and Llandrindod in Wales. There were large differences in nutrient concentrations between sites, with Newcastleton generally having the highest nitrogen- and phosphorus- based nutrient concentrations and Wauchope the lowest. Both sites had a similar soil structure, with the soil at Scootmore having a lower ability to capture moisture. Scootmore experienced the highest temperatures during the growing season and Wauchope the lowest. There was little difference in precipitation levels between sites but there were large differences between years. After 10 years of growth in the field, height, diameter and wood density (using the Pilodyn® technique) were measured. The resulting data showed that Newcastleton and Wauchope were similar and had greater tree growth, whereas Scootmore and Llandrindod were also similar but had smaller tree growth but higher wood density. However, a high mortality rate at Llandrindod excluded this site from further analysis. The 10-year data were used to classify the clones into clusters, and a clone representative of each cluster was chosen for further analysis. The selected clones showed the same growth patterns between sites; C20177 had largest growth rate; C20211 had smallest growth rate but higher wood density; C20208 was intermediate in terms of growth and wood density. However, large variation was apparent at each site, a result of environmental impacts on the growth rates. Chlorophyll, total nitrogen (N) and phosphorus (P) were extracted from differently aged needles, at different heights in the canopy for each clone at each site. N and р did not vary between clones or heights in the canopy, although did increase with increasing needle age. The distribution of chlorophyll followed light intensity patterns (increasing in shaded older and lower canopy needles) and was significantly higher in C20177. All foliar constituents were higher in Newcastleton trees and lowest in Scootmore. Foliar constituents reflected the nutrient concentration in the soils, although Scootmore had lower foliar concentrations than expected, which may be a result of the reduced moisture availability at this site. The lower uptake of nutrients at Scootmore explains the lower growth rate at Scootmore. Photosynthetic light response curves showed highest photosynthetic and respiration rates at Newcastleton and showed lowest rates at Wauchope. There was little difference in rates between clones or position in the canopy. Various parameters of light efficiency showed little difference between clones, position in the canopy or site. Differences in total non-structural carbohydrates were evident between sites (Wauchope had the highest concentrations) and between clones (C20177 had the lowest). Lower carbohydrate levels in C20177 reflected the greater growth rates by this clone. Destructive biomass sampling of above-ground organs reflected the results of the earlier height, diameter and wood density measurements, indicating that the clones had not changed growth patterns between the years 2000 and 2004. Between sites, only C20177 showed a change in carbon (C) allocation, with a switch from allocating the majority of C to the trunk at favourable sites (Newcastleton) to allocating the majority of с to branches under nutrient or water stress (Wauchope and Scootmore respectively), с allocation below- ground showed no clear pattern between clones, although fine root density was lowest for C20177, suggesting this clone was less effected by nutrient or water stress. Differences in С allocation below-ground between Wauchope and the other two sites also suggested that nutrient concentration had a greater effect on coarse roots. Parameters were calculated from the observed data and used to simulate photosynthetic rates of Sitka spruce in a process-based model of tree evapotranspiration. A comparison between observed and simulated data showed that the model predicted seasonal, site and clonal differences but the absolute values were overestimated at Newcastleton and underestimated at Wauchope and Scootmore. A sensitivity analysis showed that six parameters largely affected the output of the model and, with the majority of these parameters extrapolated from the literature; they would explain the large differences between simulated and observed data.
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Chandler, John William. "Effects of mineral nutrient supply on needle growth and photosynthesis in Sitka spruce (Picea sitchensis (Bong.) Carr.)." Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/13354.
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Clarke, Gary C. "Patterns of cone production in Sitka spruce (Picea sitchensis (Bong.) Carr.) and the prediction of cone crops." Thesis, University of Aberdeen, 1997. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU090388.
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The location of cones in crowns of grafts and mature planted tress was studied in detail and relationships between cone type and shoot characteristics were investigated. The results enabled a regression model to be developed to relate cone counts in certain crown zones to overall cone bearing. It was demonstrated that there are patterns of cone production in the crowns of Picea sitchensis. Preferred zones for female bearing are high in the tree. Male cones tend to occur lower in the tree and more proximal to the stem than female cones. As total female cone production increases, cones are borne progressively further down the tree and towards the main stem. In all cases there were shoots that remained vegetative, regardless of total cone bearing. There were also interactions between the type of cone and the nature of the bearing shoot. On lower order shoots both male and female cones tended to be borne in the proximal lateral position. On progressively weaker shoots there is a tendency for cones to be borne in progressively more distal positions. The same progress of cone bearing - from proximal to distal positions - occurred on shoots of decreasing size. On forest trees the vast majority of cones are borne on trees of above average dimensions. Of the three measured variables (height, dbh and crown depth) height appeared to be the most important in influencing cone production. Prognostic tree and stand models were developed which were quite successful in predicting cone production in forest stands, particularly at low or zero levels of bearing. The presence of female cones on the bearing shoots affected both the development of more proximal buds on that shoot and the characteristics of offspring shoots. Offspring shoots on bearing parents were smaller and tended to bear fewer needles. The effect on the number of buds formed was not conclusive.
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Townsend, John Andrew. "Effects of elevated carbon dioxide, water and nutrients on the growth and physiology of Picea sitchensis (Bong.) Carr." Thesis, Lancaster University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358802.
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Dobson, Martin C. "Fluxes to, and effects of Oâ†3 and SOâ†2 on Picea sitchensis, P. abies, and Fagus sylvatica." Thesis, University of Ulster, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.258232.
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Barton, Craig V. M. "Effects of elevated atmospheric carbon dioxide concentration on growth and physiology of Sitka spruce (Picea sitchensis (Bong.) Carr.)." Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/10744.
Full textAbstract:
The aim of this thesis is defined by the title, and two experimental approaches were used to investigate different aspects of the effect of elevated [CO2] on Sitka spruce; firstly the long term effect on mature tissue using branch bags and secondly, the interaction between [CO2] and nutrient supply rate on the growth and physiology of seedling trees. Six branches of six 16 year-old Sitka spruce trees were continuously exposed to elevated [CO2] (700 μmol mol-1) for four years. Branch growth, shoot numbers, needle size, stomatal density, nutrient and carbohydrate concentration, photosynthesis and stomatal conductance were measured throughout the experiment. There was no effect of elevated [CO2] on the growth of the branches or needles, or on the nutrient or carbohydrate concentrations of needles. Neither was there evidence for an acclimation of photosynthesis or stomatal conductance to growth in elevated [CO2] in current year needles. However, there was some down-regulation of photosynthesis in one-year old needles coincident with an increase in soluble carbohydrate concentration. In a second experiment one-year old seedlings were re-potted into sand and grown for eight months in open-top chambers in either ambient or 700 μmol mol-1 [CO2]. They were supplied with nutrients at two rates: a high rate designed to permit maximum growth rate, and a low rate 1/10 the high rate. Growth was measured each week and six harvests were made during the experiment. A purpose built whole-tree gas exchange system was used to measure independently above and below ground CO2 fluxes over 24 hours. Shoot photosynthesis responses to [CO2] and needle nutrient and carbohydrate concentrations were also measured. Elevated [CO2] enhanced growth and increased allocation to roots at both high and low nutrient supply rates, but growth enhancement was larger at the high nutrient supply rate.
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Drago-Toscano, Claudia. "Variation in defence mechanism activities in Sitka spruce (Picea Sitchensis (Bong.) Carr.) and its relation to disease resistance and susceptibility." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329961.
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Davies, Owen. "Measuring and modelling Sitka spruce (Picea sitchensis (Bong.) Carrière) and birch (Betula spp.) crowns, with special reference to terrestrial photogrammetry." Thesis, Bangor University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431791.
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Murray, Maureen B. "Effects of elevated atmospheric carbon dioxide and nutrients on the growth, phenology and physiology of Sitka spruce [Picea sitchensis (Bong.) Carr.]." Thesis, University of Edinburgh, 1997. http://hdl.handle.net/1842/11206.
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The aim of this thesis was to investigate the effects of elevated [CO2] and varying nutrient supply rates on the growth, phenology and physiology of Sitka spruce (Picea sitchensis (Bong.) Carr.).Two approaches were taken both using open top chamber facilities to fumigate seedling with either ambient (355 μmol mol-1 Co2) or elevated (700 μmol mol-1 CO2). Firstly, a long term study on the direct impact of elevated [CO2] was undertaken, this experiment ran for three consecutive years. Comparisons between responses obtained after one and three years exposure to elevated [CO2] were made. In addition, the impact of growing seedlings in OTCs per se was also investigated. Secondly, a study was conducted into the interaction between [CO2] and nutrient supply rate on growth, phenological and physiological responses. The effects of OTCs were also included in this experiment. Biomass accumulation was always enhanced by elevated [CO2] when nutrients were not limiting. Biomass stimulation as a result of elevated [CO2] was 16 and 37 % for seedlings with a foliar [N] of 1.9 and 2.4 % respectively. However, there was no enhancement at a foliar [N] of 0.9 %. A similar result was also observed in the long term study. There was no significant chamber effect on biomass but seedlings growing inside OTCs were 25 % taller. Biomass allocation was affected by [CO2], nutrient supply rate, growth inside OTCs and experimental duration. The amount of biomass allocated to roots was increased by elevated [CO2] and decreasing nutrient supply rates, with those seedlings receiving elevated [CO2] and low-N supply rates having the highest R/S ratios. Growth inside OTCs reduced the amount of biomass allocated to roots. Seedlings receiving elevated [CO2] and low nutrient supply rates had smaller amounts of biomass allocated to stems. Total leaf area and mass were both increased by elevated [CO2] and increasing nutrient supply rate but there was no significant effect of elevated [CO2] on specific leaf area, leaf area ratio or leaf mass ratio. Elevated [CO2] significantly affected bud phenology, delaying budburst and advancing budset, thereby reducing the growing season of seedlings with foliar [N] of 2.0 % or below. Increasing nutrient supply rates lengthened the growing season per se. Phenology of seedlings with a foliar [N] of 2.4% were not affected by elevated [CO2]. There was a large clonal variation in the phenological response to [CO2] and the effect of OTC was bigger than that of [CO2]. The effect of elevated [CO2] and climatic warming on spring frost damage was modelled and future risks of damage were predicted to decrease.
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Santos, Fernandez Fernando Antonio dos. "Responses of rodent populations to spatial heterogeneity and successional changes within Sitka spruce (Picea sitchensis) plantations at Hamsterley Forest, County Durham." Thesis, Durham University, 1993. http://etheses.dur.ac.uk/1200/.
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Populations of woodmice (Apodemus sylvaticus), bank voles (Clethrionomys glareolus) and field voles (Microtus agrestis) were studied by five-trapping in Sitka spruce plantations at Hamsterley Forest, northeast England, from February 1990 to June 1992. The study was carried out at two distinct spatial scales. At the coarser spatial scale, the effects of successional change and of spatial (intersite) heterogeneity within the forest were compared by censusing rodent commmunities in sites representing three successional stages: mature plantations (about 40 years after planting), clear-fellings and young plantations (5-8 years after planting). In, mature plantations woodmice and bank voles were both abundant, , in clear-fellings the former were usually dominant and in young plantations field voles were also abundant alongside' the other two species. Pooling all sites, in young plantations rodent communities had highest diversity and evenness, mostly because of an inter-site component @-diversity). On a site-by-site basis, in young plantations communities had neither higher a-diversity nor evenness than in mature plantations. Clear-fellings showed least diversity and evenness. Multivariate analyses revealed marked taxonomic and structural changes in vegetation during succession and how the rodents responded to such changes. Within young plantations bank voles were associated with dense ground cover, provided mostly by heather. Field voles. were associated with the non-palatable grass Deschwnpsia flýxuosa and to palatable grasses as well. Woodmice were habitat generalists, but their abundance was negatively correlated with that of field voles. Spatial heterogeneity in soils explained much of the inter-site variation in ground vegetation which in turn explained much of the P-diversity in rodent communities in young plantations. At the finer spatial scale, populations of woodmice and bank voles were studied by monthly trapping in five 0.8 1 ha grids within an habitat mosaic produced by the felling of a plantation of mature Sitka spruce. Inter-grid movements were frequent for both species, but especially woodmice, which also had larger home ranges. Population dynamics of woodmice in the whole mosaic were apparently similar to patterns described previously in other habitats, except that density-dependent reduction of survival and reproduction by late autumn was more severe than usual. Woodmice were more abundant in 1991 than in 1990, apparently due to increased seed supply. Bank voles, in contrast, did not show regular annual fluctuations in numbers. Although breeding stopped in both winters, population densities increased steadly during 1991 and remained high until spring 1992. Clear-felling of a part of the study area had little immediate effect on populations of either species; responses to clear-felfing were gradual rather than sudden. The experimental removal of tree brashings from recent clear-felfings scarcely affected the populations of woodmice, but made the clear-feUings unsuitable for bank voles, apparently due to the reduced availability of shelter. Habitat selection within the whole habitat mosaic was density-independent in bank voles, but density-dependent in woodmice. In the later species, demographic differences among local subpopulations accounted for most of the observed density-dependent changes in spatial distribution, although inter-grid movements also played an important part. * The responses of each rodent species to spatial and temporal heterogeneity and a possible role of density-dependent habitat selection in population regulation are discussed.
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Roach, Christopher Robert. "Elucidation and characterization of genes associated with montbretin a biosynthesis within crocosmia x crocosmiiflora and white pine weevil defense in picea sitchensis." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/63549.
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Emmett, Bridget A. "The effects of harvesting on soil nitrogen transformations in a Sitka spruce (Picea sitchensis (Bong.) Carr.) plantation at Beddgelert forest (N. Wales)." Thesis, University of Exeter, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253559.
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Henderson, Callum George McKenzie. "The nature of high altitude precipitation and its effect on Scots pine (Pinus sylvestris L.) and Sitka spruce (Picea sitchensis (Bong.) (Carr.))." Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/10952.
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The nature of high altitude precipitation and its effect on Scots pine (Pinus sylvestris L.) and Sitka spruce (Picea sitchensis (Bong.) Carr.) was investigated. Scots pine and Sitka spruce are important British forestry species and the effect of acidic cloud on these has been inadequately investigated. At a field site in the Scottish Southern Uplands, impacted cloudwater was either collected from, or measured with a microelectrode in situ on, artificial polypropylene snoots which closely mimicked live shoots. Temporal variation of pH within cloud deposition events was strong and the potential for damage by acid clouds was seen to be high. Impacted cloudwater was also collected from, or measured in situ on, live shoots and the interchange of ions between shoots and cloudwater investigated. Leaching of basic cations was considerable but not sufficient to neutralize cloudwater acidity. Dry deposition on live shoots appeared to increase the acidity of impacted cloudwater on shoots. The change in pH of evaporating droplets was measured in situ with the microelectrode. Droplet acidity increased dramatically as a result of evaporation. The potential for damage by snow was investigated by collecting and analysing snowmelt. Ground snowpack showed an initial flush of ions (including H+) on melting, followed by a steep decline to very low ion concentrations. Meltwater from live shoots did not show this flush/decline but did exhibit higher acidity levels which were also related to the pathway of the snowmelt through the snowpack. A series of four glasshouse experiments were undertaken in which a system for applying simulated acid cloud (SAC) was developed. Six to eight-year-old Scots pine and Sitka spruce were subjected to SAC at pH 5.6, 3.0 and 2.5. Considerable leaching of Ca, Mg, K, NO~-N and PO~-P occurred and showed an increasing response to increasing acidity of SAC. Both extension growth and needle area declined with increasing acidity but the decline was statistically insignificant. Visible injury on Scots pine needles was limited to those subjected to SAC at pH 2.0. Sitka spruce damage occurred to a very small extent at pH 2.5 but was again largely restricted to pH 2.0. Artificial abrasion of needles did not increase susceptibility to acid damage. Acid damage generally progressed from tip to base and at the junction of the brown and green tissue a darker brown band formed. Tissue underlying brown areas was subject to cell collapse and underneath the dark bown band the extracellular spaces were filled with an unknown material and the cells had not collapsed. The structure of the epicuticular wax was not affected by SAC acidity and even over necrotic areas the crystalline wax remained intact. The functional integrity of the cuticle, investigated by measuring cuticular conductance and contact angles, was unaffected by SAC. Controlled experiments on the changing acidity of evaporating droplets took place with three-year-old Scots pine and Sitka spruce in a large wind-tunnel, again with the use of the microelectrode. Droplet acidity again increased dramatically evaporation and there was also a close relationship between the increase of acidity of the droplet and that predicted by a direct relationship to the amount of water evaporated. Scots pine and Sitka spruce thus appear to be resistant to direct effects of acid cloud at pH 3.0 which is the lowest generally encountered in the Scottish Southern Uplands. However acidity enhancement through evaporation, extreme pH values at the start or finish of cloud events and high acidity flushes at the start of snowmelt may all expose trees to pH levels approaching those causing direct damage. In addition, the nutrient budgeting of trees may be adversely affected and lead to long term reductions in growth.
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Petruncio, Markian Demetrius. "Effects of pruning on growth of Western hemlock (Tsuga heterophylla (Raf.) Sarg.) and Sitka spruce (Picea sitchensis (Bong) Carr.) in Southeast Alaska /." Thesis, Connect to this title online; UW restricted, 1994. http://hdl.handle.net/1773/5521.
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Prügel, Bärbel. "Contribution à l'étude des modifications chimiques des cires cuticulaires de picea abies (L. ) Karst et de picea sitchensis (Bong. ) carr. En relation avec le dépérissement forestier et l'augmentation du taux de CO2 dans l'atmosphère." Nancy 1, 1994. http://www.theses.fr/1994NAN10141.
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Dans le cadre de ce travail, la composition chimique des cires cuticulaires de Picea abies et de Picea sitchensis a été étudiée, aussi bien au niveau qualitatif qu'au niveau quantitatif. Un inventaire des composés contenus dans les cires des deux espèces a été établi en utilisant diverses méthodes chromatographiques. Les cires des deux espèces sont principalement constituées d'estolides, d'alcools secondaires, de diols et d'acides gras, mais dans des proportions différentes selon l'espèce considérée. Au niveau qualitatif, les cires des deux conifères se différencient par des classes de substances mineures, telles que les esters méthyliques et éthyliques et les aldéhydes à longue chaîne. A partir d'observations par microscopie électronique à balayage, le dépérissement forestier a été lié à un vieillissement précoce des aiguilles. Cette hypothèse a été testée en comparant la quantité et la composition chimique des cires de picea abies en fonction de l'âge des aiguilles, du niveau de dépérissement de l'arbre et de la région de prélèvement. Au niveau des paramètres étudiés, les phénomènes de vieillissement et de dépérissement entraînent des modifications différentes de la composition des cires. Cependant, chacun des phénomènes se présente de la même façon dans toutes les régions considérées. L’effet de différents taux de CO2 atmosphérique sur la composition des cires cuticulaires a été étudié principalement à l'aide des chambres à ciel ouvert de 4 stations expérimentales. Pour un des sites, chaque taux de CO2 a été combiné avec un traitement de l'air différent (air purifié et air non purifié), différencié essentiellement par la concentration d'ozone. Une augmentation du taux de CO2 entraînerait des modifications différentes de celles constatées en relation avec le dépérissement et le vieillissement. De plus, une interaction ozone-CO2, probablement due à une perturbation de l'ouverture stomatique par l'impact de l'ozone, a pu être observée
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Zerva, Argyro. "Effects of afforestation and forest management on soil carbon dynamics and trace gas emissions in a Sitka spruce (Picea sitchensis (Bong) Carr.) forest." Thesis, University of Edinburgh, 2004. http://hdl.handle.net/1842/574.
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The establishment and intensive management of forests for the production of timber can have significant effects on the soil carbon dynamics. The establishment of forest on organic soils under grasslands may lead to substantial losses in soil carbon, due to the site preparation for the planting of trees and other disturbances. This is gradually compensated by carbon accumulation in tree biomass as the forest grows until clearfelling at maturity may initiate another substantial carbon loss. This study had two main aims. The first was to investigate the long-term effects of forest establishment on natural grassland as well as clearfelling and re-growth of the forest during second rotation, by looking at the changes in soil carbon stocks and soil carbon balance in a Sitka spruce (Picea sitchsensis) in Harwood (N. E. England). Secondly, to investigate the short-term effects of forest clearfelling on the fluxes of soil CO2, N2O and CH4 and on the environmental factors (soil temperature, water content and water table depth) affecting them. The fluxes were initially measured in two mature stands (40-years old) during one growth season. One of the two stands was subsequently clearfelled while the other was kept intact and fluxes were measured for a further ten months after clearfelling. The relationships between these fluxes and the environmental factors were also examined. The study also investigated the spatial variability of soil CO2 emissions using geostatistical approaches. The soil CO2 fluxes were measured with two methods, a closed dynamic chamber and a closed static chamber, giving the opportunity to compare their relative performance. A performance further investigation on this discrepancy between the two methods took place in lab experiments and on a soil monolith, excavated from the 40-year old stand and kept under controlled conditions in the greenhouse.
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Kakei, Mahdi. "Effects of lime application on fine-root development of Sitka spruce (Picea sitchesis (Bougard) carrie) trees grown on deep peat soils." Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295396.
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Robert, Jeanne A. "Terpenoid profiling and biosynthesis in Sitka spruce (Picea sitchensis) genotypes that are susceptible or resistant to attack by the white pine weevil (Pissodes strobi)." Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/23356.
Full textAbstract:
White pine weevil, Pissodes strobi, is an insect that occurs throughout Canada that attacks a number of conifers including Sitka spruce, Picea sitchensis, a commercially and ecologically important tree for coastal B.C.. Because of attack by weevils, Sitka spruce is no longer replanted as a commercial species. The re-introduction of this species would be a valuable asset for sustainable coastal forestry. My research addresses the terpene composition and the molecular-genetic underpinning of Sitka spruce resin defenses against attack by white pine weevil.
In this thesis, I report that terpene profiles can be used to classify resistant tree genotypes. I analysed 111 different genotypes in order to determine the relationship of mono- and diterpenoid oleoresin compounds with the resistance rating. Dehydroabietic acid, a diterpene, was identified as a strong indicator of resistance. Two monoterpenes, (+)-3-carene and terpinolene were also associated with resistance in genotypes originating from the Haney region, an area which may have been subject to higher weevil pressure. In addition, I characterized weevil behavior and physiology (feeding patterns, host choice, ovary development, egg laying behavior, and larval development) in response to an extremely resistant Sitka spruce genotype (H898) in comparison to a highly susceptible genotype (Q903). My results suggest that the highly resistant genotype H898 has defense mechanisms that deter both male and female weevils during host selection and mating, that cause delayed ovary development in females, and prevent successful reproduction of weevils on H898 trees. Finally, I have identified the first (+)-3-carene and (+)-sabinene synthase genes in Sitka spruce. These terpene synthase (TPS) genes have very similar sequences, yet the encoded enzymes have different product profiles; this shows a new level of genetic diversity in the spruce TPS gene family. In addition, different (+)-3-carene synthase genes are expressed in the resistant H898 tree genotype producing large amounts of (+)-3-carene, versus the susceptible Q903 tree genotype that produces trace amounts of (+)-3-carene. This information will support the identification and breeding of resistant Sitka spruce in order to re-introduce it as a viable, native commercial species.
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Evans, Lynn Patricia. "The effects of increased atmospheric carbon dioxide on growth and morphology of seedlings of silver birch (Betula pendula Roth.) and Sitka spruce (Picea sitchensis (Bong.) Carr.)." Thesis, University of Edinburgh, 1994. http://hdl.handle.net/1842/14808.
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The objective of this study was to determine the effects of long-term exposure to elevated CO2 on the growth and morphology of seedlings of Sitka spruce and silver birch, with a focus on the effects of elevated CO2 on the expansion, surface characteristics, specific leaf area, anatomy and chlorophyll content of leaves of silver birch. Seedlings of Sitka spruce and silver birch were placed in pots in open top chambers receiving ambient or elevated CO2. After one growing season there was a significant increase in biomass production in seedlings of Sitka spruce grown in elevated CO2 compared to those grown in ambient CO2, but after eighteen months this effect had disappeared. The initial increase in biomass was a result of a significant increase in root mass. At the end of the second growing season there was no effect of elevated CO2 on allocation of dry mass. There was no effect of elevated CO2 on total number of branches produced at the end of the second growing season but there was an increase in the rate of branch production. Nitrogen, phosphorus and potassium concentration of leaves was reduced in plants grown in elevated CO2. After one growing season biomass was increased in elevated CO2 plants by ca 20%, rates of photosynthesis were also higher in elevated CO2 plants. There was no effect of CO2 treatment on root: shoot ratio. There was a significant increase in branch production in plants grown in elevated CO2, but despite an increase in leaf area production early on in the growing season, there was no difference in total tree leaf area at the end of the growing season. Nitrogen, phosphorus and potassium concentration of leaves was reduced in plants grown in elevated CO2 and leaves on elevated CO2 plants senesced ca one week earlier than leaves of plants grown in ambient CO2.
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MARTINI, VALENTINA. "The role of terpenes in chemical defences of forest plants." Doctoral thesis, 2010. http://hdl.handle.net/2158/545766.
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Gapare, Washington Jingo. "Genetic diversity and spatial population structure of Sitka spruce (Picea sitchensis (Bong.) Carr.) : implications for gene conservation of widespread species." Thesis, 2003. http://hdl.handle.net/2429/15916.
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Knowledge of genetic diversity and population structure is of fundamental
importance in the development of gene conservation sampling strategies to capture
and preserve allelic diversity. Such knowledge is critical if we are to understand how
to manage and maintain diversity in species and populations. To assess the effects
of sampling strategy on capture of allelic diversity in widespread species, I studied
Sitka spruce (Picea sitchensis (Bong.) Carr) populations as a model. Sitka spruce is
a conifer that occupies wide geographic and ecological niches from 33° N to 60° N
latitude along the Pacific coast of North America. A total of 1600 individual trees
were sampled in eight populations classified as core or peripheral based on
ecological niche, and continuous or disjunct based on distribution. In each
population, 200 trees were spatially mapped and genotyped for eight cDNA-based
sequence-tagged-site (STS) co-dominant markers. One important finding of this
study is the similarity in genetic diversity as measured by expected heterozygosity
between core populations (mean HE = 0.58) and peripheral populations (mean HE =
0.56). Another remarkable result found by this study is strong spatial structure as
evidenced by coancestry in peripheral populations, both continuous and disjunct, but
not in core populations. For example, trees located within 50 metres of each other in
peripheral, disjunct populations had coancestry values greater than 0.20 while in
core populations, trees within the same distance class had coancestry values below
0.06. Differences in population structure were attributed to an aggregation of similar
multi-locus genotypes, in a structured, isolation by distance manner in peripheral
populations, both continuous and peripheral but not in core, continuous populations.
Irrespective of population classification, over 75% of the alleles were common and
widespread. Only one allele, representing two percent of all alleles was classified as
rare and localized on average, and this allele was limited to one core, disjunct and
two peripheral, disjunct populations. To capture localized alleles (both common and
rare), sampling should cover more populations over the geographic and ecological
range of species at a cost of fewer individuals per population. The conservation of
peripheral populations may present the best opportunity for preserving rare alleles.Forestry, Faculty of
Graduate
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Pearson, Audrey F. "Relationships between site index of Sitka spruce (Picea sitchensis(Bong.) Carr.) and measures of ecological site quality in the Eastern Queen Charlotte Islands." Thesis, 1992. http://hdl.handle.net/2429/3042.
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Relationships between measures of ecological site quality and height
growth of Sitka spruce [Picea sitchensis (Bong.) Carr), measured as site index
(metres at 50 years at breast height), were investigated for the eastern Queen
Charlotte Islands using multiple linear regression techniques. Temperature
and light were assumed to be similar in a region of similar climate, expressed
as biogeoclimatic subzone, and the investigation focused on measures of
moisture and nutrients. This study tested the hypothesis that the
classification units of biogeoclimatic ecosystem classification system are good
indirect estimates of ecological site quality so are able to predict forest growth.
Fifty-five plots were chosen for study to represent a wide range i n
ecological site quality and geographic variation. Individual measures of
moisture and nutrients were represented as categorical variables; soil moisture
and nutrient regime; and continuous variables; soil nutrients and predicted
moisture deficit in combination with soil physical measures. Soil moisture and
nutrient regimes were represented as spectra of indicator species groups. The
synoptic effect of individual measures of moisture and nutrients were
expressed as site associations and assumed to be represented by plant
associations. The relationship between the categorical and continuous
variables for soil nutrients was also examined.
The most successful models used the BEC classification units; soil
moisture regime, soil nutrient regime and site association. Multiple linear
regression models using either soil moisture plus soil nutrient regimes or site
associations were equally successful in explaining variation in (ln) site index
(adjusted R2 = 0.80; I2 = 0.79). However, the former should be considered the
superior model for predictive purposes since the variance of the latter model
was not homogeneous. The soil nutrient regime model was as successful in
explaining variation in site index as the best continuous model (mineral soil
mineralizable N plus forest floor mineralizable N, extractable calcium and
potassium) (adjusted = 0.40 versus 0.42). The soil moisture regime model
was more successful than those using continuous variables (adjusted =
0.45 versus no relationship). The lack of relationship was attributed to
inaccuracy of the water balance models due to their lack of calibration for this
location and forest type. There was a moderate relationship with site index and
plant associations (adjusted R2 = 0.49); however vegetation is subject to
change with succession over time so would be difficult to apply for predictive
purposes. Indicator species groups showed no relationship with site index,
likely due to the paucity of understorey species from canopy closure and
intense browsing by introduced deer.
The soil nutrient regime classification was well supported by a
discriminant analysis using soil chemical nutrients which correctly classified
the plots in 83% of the cases, on average. The soil moisture regime
classification could not be tested since the models used to estimate moisture
deficit in this study were considered too inaccurate. Continuous synoptic
versus categorical models could also not be compared for the same reason.
It was concluded that the units of the biogeoclimatic ecosystem
classification were good indirect measures of ecological site quality and good
predictors of forest growth. The equations generated in this study need to be
tested with independent data and further investigation is necessary to
determine moisture relationships for Sitka spruce.
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Prior, Natalie Annastasia. "Creating a somatic embryogenic system to study resistance traits to the white pine weevil (Pissodes strobi Peck.) in Sitka spruce (Picea sitchensis (Bong.) Carr)." Thesis, 2010. http://hdl.handle.net/1828/3363.
Full textAbstract:
A somatic embryogenic system was created using material from the British
Columbia Ministry of Forests and Range’s Sitka Spruce (Picea sitchensis (Bong.) Carr)
breeding program for resistance to the white pine weevil (Pissodes strobi Peck.). The
goal was to provide a system that could aid in understanding the phenotypic and
genotypic variation that exists in these traits. Embryogenic lines were derived from
controlled crosses of parental genotypes previously ranked for the abundance of three
physical bark traits: sclereid cells, constitutive resin canals and traumatic resin canals.
The number of filled seeds per cone from controlled pollinations was low, with a mean of
9.4 ± 6.8 (mean ± SD), compared to open-pollinated material, which had greater than 40
seeds per cone. The mean induction rate (to embryogenic cultures) was 7 %, ranging
from 0 % to 56 % by cross. Of 135 genotypes, 88.1 % produced mature embryos. The
number of embryos produced varied by culture. Nearly all (44 of 45) genotypes
germinated, with a mean germination rate of 80 %. The overall conversion rate of
somatic embryos to plants was 5.5 %. A novel method of cryopreservation that used a
temperature pretreatment but did not require dimethyl sulfoxide was tested.
Embryogenic cultures were recovered from 31 % of genotypes (n = 112). Genotypic and
phenotypic variation were observed during each stage of the somatic embryogenic
process. This project demonstrated that somatic embryogenesis and cryopreservation can
be used to create a system to study phenotypic and genotypic variation in Sitka spruce.Graduate
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Bothwell, Karen Sheila. "The nitrogen nutrition of lodgepole pine (Pinus contorta var. contorta) and Sitka spruce (Picea sitchensis (Bong.) Carr.) on a cedar-hemlock cutover on northern Vancouver Island." Thesis, 2000. http://hdl.handle.net/2429/10351.
Full textAbstract:
Nursing mixtures with pine or larch have been widely used in Britain and Ireland to aid the establishment of
Sitka spruce (Picea sitchensis (Bong.) Carr.) on low-nitrogen, Calluna dominated heathlands and
peatlands. The overall result is increased height and diameter growth and increased foliar N concentrations of the spruce and increased N mineralization rates in the forest floor in mixed stands, about
8-10 years after planting. Cedar-hemlock cutovers are ecologically analogous to Calluna sites, both being
dominated by ericaceous shrubs and having extremely low nitrogen availability. Growth check symptoms,
including reduced leader growth and chlorosis after 5 to 8 years are akin to symptoms observed in British
and Irish plantations. A nurse trial was established on a cedar-hemlock cutover on northern Vancouver
Island with the objective of testing the efficacy of lodgepole pine (Pinus contorta Dougl. var. contorta) and
western white pine (Pinus monticola Dougl. ex D. Don) as nurse species for Sitka spruce regeneration.
There were three treatments (pure spruce, spruce in mixture with lodgepole pine and spruce in mixture with
white pine), replicated three times. The treatments were established at three different spacings. The trial
was remeasured at ten years, however there was no evidence of increased height or diameter growth or
increased foliar nitrogen concentrations of the spruce in mixture. Possible reasons for this are suggested.
What was evident was the superior growth and nutrition of lodgepole pine on this nitrogen-poor site.
The second part of the research focused on examining possible mechanisms leading to the superior growth
of lodgepole pine on sites with low nitrogen availability. A field biomass harvest of pine and spruce trees
from a cedar-hemlock cutover and a greenhouse bioassay were conducted to examine whether pine
accessed more nitrogen, distributed more biomass and nitrogen above ground, and/or was more efficient in
the use of the nitrogen taken up through greater production of biomass per unit of nitrogen taken up and/or
through greater nitrogen retranslocation at time of senescence. Rooting distribution patterns were
examined to determine if pine might have access to different nitrogen pools. Some mycorrhizae, including
some species specific to pine, have access to organic forms of nitrogen, therefore mycorrhizal
assessments of the communities infecting the pine and spruce were conducted. The abilities of pine and
spruce to access different nitrogen sources, both inorganic and organic were also tested. Lodgepole pine
took up more nitrogen and had much larger aboveground biomass production. The greater growth and
nitrogen status of pine were attributed to greater foliage efficiency. Pine had a deeper root system and the
root tips were heavily infected with mycorrhizal fungi, which have high proteolytic activity such as Suillus.