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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The isozyme technique - a short-cut to the genes of our forest trees? illustrations using Pinus sylvestris L Isozymtekniken - en genväg till generna i våra skogsträd? illustrationer med hjälp av Pinus sylvestris L. /

Rudin, Dag. January 1977 (has links)
Thesis (doctoral)--Umeå Universitet, 1977. / Summaries in English and Swedish. Includes bibliographical references.
2

Seed set and the proportion of progeny due to self-fertilization in a Douglas-fir seed orchard /

Omi, Steven Katsu. January 1983 (has links)
Thesis (M.S.)--Oregon State University, 1983. / Typescript (photocopy). Includes bibliographical references (leaves 69-75). Also available on the World Wide Web.
3

Variação genética para os caracteres fisiológicos, bioquímicos e nutricionais em sementes de uma população base de Myracrodruon urundeuva procedente de Aquidauana-MS

Berti, Christian Luis Ferreira [UNESP] 02 August 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-08-02Bitstream added on 2014-06-13T21:07:43Z : No. of bitstreams: 1 berti_clf_dr_ilha.pdf: 1092178 bytes, checksum: 68a8efc7ddc8d81323b76604a8b8df95 (MD5) / Dentre as espécies que vêm sofrendo interferência antrópica encontra-se a aroeira (Myracrodruon urundeuva Fr. All.). Como estratégias de conservação propostas, destacam-se a ex situ e entre as estratégias para avaliar a variabilidade genética destaca-se a genética quantitativa, onde são estimados parâmetros genéticos para alguns caracteres. As árvores estudadas pertencem a uma população de polinização aberta de Myracroduon urundeuva (F.F. & M.F. Allemão) localizada na rodovia de acesso à cidade de Aquidauana, MS. Este trabalho tem como objetivo quantificar a variação genética para os caracteres bioquímicos, físicos, fisiológicos e nutricionais em sementes de Myracrodruon urundeuva, identificar qual(is) teste(s) mais promissores para a determinação da viabilidade em campo de acordo com os teores dos mesmos e fornecer subsídios para conservação in situ e ex situ de Myracrodruon urundeuva. Foram realizadas análises físicas e fisiológicas (germinação, condutividade elétrica e massa de 100 sementes) e análises dos teores de: carboidratos, lipídios, amido, proteínas (albumina, globulina, prolamina e glutelina) e macronutrientes (N, P, K, Ca, Mg e S) em sementes e obtidas as estimativas de parâmetros genéticos. O conjunto de análises físicas e fisiológicas apresenta-se como o mais apropriado a obter a chance de maior ganho genético por apresentarem os maiores valores de coeficiente de variação relativa, seguidos, respectivamente, de nutricionais e bioquímicos. As médias obtidas para os caracteres bioquímicos foram: albumina (61,34 mg g-1), globulina (10,87 mg g-1), prolamina (58,19 mg g-1), glutelina (289,54 mg g-1), lipídios (21,70 mg g-1), amido (2,61 mg g-1) e carboidratos totais (24,00 mg g-1). Para os caracteres físicos e fisiológicos as médias obtidas foram: condutividade elétrica... / Among the species that have suffered human interference is mastic (Myracrodruon urundeuva Fr. All.). How conservation strategies proposals stand out ex situ and between strategies to assess the genetic variability highlights the quantitative genetics, which are estimated genetic parameters for some characters. The trees studied belong to a population of open-pollinated Myracroduon urundeuva (F.F. & M.F. Allemão) located on the access road to the town of Aquidauna, MS. This study aims to quantify the genetic variation for characters biochemical, physical, physiological and nutritional seeds M. urundeuva identify which one (s) test (s) more promising for the determination of viability in the field according to the levels of the same and provide grants for conservation in situ and ex situ M. urundeuva. Analyses physical and physiological (germination, electric conductivity and weight of 100 seeds) and analysis of the levels of: carbohydrates, lipids, starch, proteins (albumin, globulin, prolamin and glutelin) and macronutrients (N, P, K, Ca, Mg and S) in seeds and obtained estimates of genetic parameters. The set of physical and physiological analysis presents itself as the most appropriate to get the chance of greater genetic gain by presenting the highest values of coefficient of relative variation, followed, respectively, nutritional and biochemical. The mean values of biochemical characters were: albumin (61.34 mg g-1), globulin (10.87 mg g-1), prolamin (58.19 mg g-1), glutelin (289.54 mg g- 1), lipids (21.70 mg g-1), starch (2.61 mg g-1) and total carbohydrates (24.00 mg g-1). For the physical and physiological characters the averages were: electrical conductivity (61.34 mg g-1), weight of 100 seeds (10.87 mg g-1) and germination (58.19 mg g-1). The characters had the following nutrient medium: nitrogen (61.34 mg g-1), phosphorus... (Complete abstract click electronic access below)
4

Variação genética para os caracteres fisiológicos, bioquímicos e nutricionais em sementes de uma população base de Myracrodruon urundeuva procedente de Aquidauana-MS /

Berti, Christian Luis Ferreira. January 2013 (has links)
Orientador: Mário Luiz Teixeira de Moraes / Coorientador: Miguel Luiz Menezes Freitas / Banca: Marco Eustaquio de Sá / Banca: Bruno Ettore Pavan / Banca: Marco Antonio Camillo de Carvalho / Banca: Camila Regina Baleroni Recco / Resumo: Dentre as espécies que vêm sofrendo interferência antrópica encontra-se a aroeira (Myracrodruon urundeuva Fr. All.). Como estratégias de conservação propostas, destacam-se a ex situ e entre as estratégias para avaliar a variabilidade genética destaca-se a genética quantitativa, onde são estimados parâmetros genéticos para alguns caracteres. As árvores estudadas pertencem a uma população de polinização aberta de Myracroduon urundeuva (F.F. & M.F. Allemão) localizada na rodovia de acesso à cidade de Aquidauana, MS. Este trabalho tem como objetivo quantificar a variação genética para os caracteres bioquímicos, físicos, fisiológicos e nutricionais em sementes de Myracrodruon urundeuva, identificar qual(is) teste(s) mais promissores para a determinação da viabilidade em campo de acordo com os teores dos mesmos e fornecer subsídios para conservação in situ e ex situ de Myracrodruon urundeuva. Foram realizadas análises físicas e fisiológicas (germinação, condutividade elétrica e massa de 100 sementes) e análises dos teores de: carboidratos, lipídios, amido, proteínas (albumina, globulina, prolamina e glutelina) e macronutrientes (N, P, K, Ca, Mg e S) em sementes e obtidas as estimativas de parâmetros genéticos. O conjunto de análises físicas e fisiológicas apresenta-se como o mais apropriado a obter a chance de maior ganho genético por apresentarem os maiores valores de coeficiente de variação relativa, seguidos, respectivamente, de nutricionais e bioquímicos. As médias obtidas para os caracteres bioquímicos foram: albumina (61,34 mg g-1), globulina (10,87 mg g-1), prolamina (58,19 mg g-1), glutelina (289,54 mg g-1), lipídios (21,70 mg g-1), amido (2,61 mg g-1) e carboidratos totais (24,00 mg g-1). Para os caracteres físicos e fisiológicos as médias obtidas foram: condutividade elétrica... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Among the species that have suffered human interference is mastic (Myracrodruon urundeuva Fr. All.). How conservation strategies proposals stand out ex situ and between strategies to assess the genetic variability highlights the quantitative genetics, which are estimated genetic parameters for some characters. The trees studied belong to a population of open-pollinated Myracroduon urundeuva (F.F. & M.F. Allemão) located on the access road to the town of Aquidauna, MS. This study aims to quantify the genetic variation for characters biochemical, physical, physiological and nutritional seeds M. urundeuva identify which one (s) test (s) more promising for the determination of viability in the field according to the levels of the same and provide grants for conservation in situ and ex situ M. urundeuva. Analyses physical and physiological (germination, electric conductivity and weight of 100 seeds) and analysis of the levels of: carbohydrates, lipids, starch, proteins (albumin, globulin, prolamin and glutelin) and macronutrients (N, P, K, Ca, Mg and S) in seeds and obtained estimates of genetic parameters. The set of physical and physiological analysis presents itself as the most appropriate to get the chance of greater genetic gain by presenting the highest values of coefficient of relative variation, followed, respectively, nutritional and biochemical. The mean values of biochemical characters were: albumin (61.34 mg g-1), globulin (10.87 mg g-1), prolamin (58.19 mg g-1), glutelin (289.54 mg g- 1), lipids (21.70 mg g-1), starch (2.61 mg g-1) and total carbohydrates (24.00 mg g-1). For the physical and physiological characters the averages were: electrical conductivity (61.34 mg g-1), weight of 100 seeds (10.87 mg g-1) and germination (58.19 mg g-1). The characters had the following nutrient medium: nitrogen (61.34 mg g-1), phosphorus... (Complete abstract click electronic access below) / Doutor
5

Douglas fir megagametophyte development in situ and in vitro

Chiwocha, Sheila 07 February 2018 (has links)
Megagametophyte development in situ and in vitro was investigated in Douglas fir to address the following questions: (1) Do endogenous levels of plant hormones change during megagametophyte development and are they associated with morphological changes? (2) Can megagametophytes be cultured prior to fertilization? (3) Can embryos be rescued from megagametophytes cultured soon after fertilization? A histochemical study of storage reserve deposition during megagametophyte development was performed with material isolated weekly for 11 weeks. Prior to fertilization, starch was detected in the neck cells of megagametophytes analyzed 9 weeks after pollination (WAP). During embryogenesis, starch was deposited in the central region of megagametophytes. Proteins and lipids were first detected in the prothallial cells in the periphery of megagametophytes isolated 14 and 15 WAP, respectively. With further development, starch was deposited in prothallial cells around the corrosion cavity, while proteins and lipids were spatially localized to prothallial cells in the periphery. In the embryo, starch accumulation was preferentially localized in the root cap and the embryonal suspensor cells at 17 WAP. A parallel study quantifying the endogenous levels of plant hormones: IAA, IAAsp, Z, ZR, iP, IPA, ABA and ABA-GE, in megagametophytes was performed. Hormones were extracted, purified and fractionated using HPLC. To correct for losses due to procedures, radiolabelled standards were added prior to extraction. The hormones were quantified using an ELISA method. On a dry weight basis, Z levels were highest in megagametophytes at the late central cell stage (8 WAP). During embryogenesis, Z levels peaked during week 13. ZR peaked twice at 13 and 17 WAP. The iP content of megagametophytes increased at 10, 13 and 17 WAP while iP.A concentration increased at 13 and 17 WAP. Prior to fertilization, the free LAA was highest in megagametophytes at 9 WAP. During embryogenesis, the major lA A accumulations occurred at I I ,13 and 15 WAP. lAAsp concentrations reached their highest levels at 10, 14 and 18 WAP. ABA content increased at 11, 13 and 17 WAP. In contrast, ABA-GE levels were relatively constant over the 11 weeks analyzed. Megagametophytes were isolated weekly from 7–10 WAP and cultured on a modified half-strength Litvay's medium supplemented with one of three auxins (NAA, IBA or 2,4-D) and a cytokinin (2 mg/L BAP). Each auxin was tested at three levels: 0.1, 1.0 or 10 mg/L. The objective was to determine whether the megagametophytes would continue to grow in culture. Megagametophytes increased in length after 9 and 18 days of culture. Auxin and cytokinin supplements had a significant effect on growth for material isolated 7 or 10 WAP. However, the viability of the archegonia rapidly declined on all the media tested. The most optimal treatment for each auxin type (BAP in combination with 0.1 mg/L NAA. 1.0 mg/L IBA or 1.0 mg/L 2.4-D) was used to initially culture pollinated megagametophytes in the embryo rescue experiment. After 21 days, megagametophytes were transferred to media containing ABA concentrations of 0.5, 20 or 40 μM. A majority of the rescued embryos were developmentally arrested at the globular stage. Only three embryos, containing over 30 cotyledons each, matured on ABA concentrations of 5, 20 or 40 μM. In conclusion, the prothallial cells of the pre-fertilization megagametophytes could be cultured for long periods and their growth was not dependent on the presence of viable archegonia. The endogenous levels of plant hormones varied with megagametophyte development and were associated with morphological changes. This information has implications for growing megagametophytes for in vitro fertilization and embryo rescue experiments. The endogenous levels of plant hormones could be used to design culture media for rescuing embryos resulting from in vitro fertilization in Douglas fir. / Graduate
6

Molecular characterization and regulation of embryogenesis-associated genes in Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco)

Chatthai, Malinee 21 December 2017 (has links)
As a direct approach to investigate the molecular basis of embryogenesis in Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco), a cDNA library made from poly(A)⁺ RNA of developing seeds was differentially screened for clones representing transcripts abundant in the developing seeds but absent in mature seeds. Of a number of clones isolated, two groups were selected for further sequence and gene expression analysis. A group of four cDNA clones (PM2S1, PM2S2, PM2S3 and PM2S4) shared a significant nucleotide and deduced amino acid sequence similarity with each other and with gymnosperm 2S seed storage protein cDNAs. The deduced amino acid sequences had low similarity with angiosperm 2S storage proteins but contained all conserved cysteine residues in an arrangement suggestive of a structural similarity between the 2S seed storage proteins from gymnosperms and angiosperms. Northern blot analysis revealed PM2S mRNAs were present specifically in seeds and temporally during seed development. However, the relatively low abundance of PM2S3 mRNAs and the decline of PM2S2 mRNAs in megagametophyte which occurred before that of the other mRNAs suggested that their expression was regulated differentially. The accumulation of PM2S transcripts in megagametophyte started during the early embryogenesis and reached a peak before that in zygotic embryos. PM2S mRNAs were present in Douglas-fir somatic embryos at the same developmental stages as those in zygotic embryos, and ABA and osmoticum stress were necessary for the expression of PM2S genes in somatic embryos. Southern blot analysis of genomic DNA suggested that the Douglas-fir 2S seed protein genes consisted of at least two sub-families each including several gene members. A gene designated gPm2Sl was isolated and sequenced. A comparison of the upstream sequence of gPm2Sl with the promoters of known 2S storage protein genes did not reveal significant sequence similarity except the presence of RY-repeated element (GCATGC), and the frequent occurrence of ACGT-containing motifs and E-box motifs (CANNTG). The 1.2-kb gPm2Sl promoter was fused to a P-glucuronidase (uidA) reporter gene and transformed into developing Douglas-fir seeds using particle bombardment and into tobacco via Agrobacterium tumefaciens. Histochemical analysis showed that the promoter was active in both systems and the gene expression was confined to endosperm and embryos of transgenic tobacco, indicating a common seed-specific regulatory mechanism between angiosperms and conifers. Another cDNA clone, PM2.1, hybridized to a 0.5 kb transcript and was predicted to encode a metallothionein (MT)-like protein. Alignment of the PM2.1 predicted amino acid sequence with other plant MT-like gene products revealed a general paucity of Cys and Cys-Xaa-Cys sequences and the presence of serine residues within the conserved Cys-Xaa-Cys motifs in the C-terminal domain. Phylogenetic analysis showed that PM2.1 grouped with class I/type 3 MT-like genes. The PM2.1 was expressed in somatic and zygotic embryos, in megagametophyte, as well as in hormone- and metal-treated seeds and seedlings. The PM2.1 transcripts were detected in the needles of 10-week-old seedlings, but not the root tissue or mature pollen. The expression of the PM2.1 gene in embryos was dependent upon ABA and osmoticum and was differentially modulated by metals, suggesting that the PM2.1 gene product may play a role in the control of microelement availability during Douglas-fir seed development and germination. Southern blot analysis of genomic DNA suggested that the PM2.1 was encoded by a multigene family. Three genomic clones were isolated and one of these clones (gPmMTa) was cloned and sequenced. The sequence analysis of its 5'-flanking region identified a number of putative regulatory elements such as ACGT-containing motifs, metal-responsive element (TGCGCC) and ethylene-responsive elements (ATTTCAAA) which may be responsible for gene transcription. DNase I-footprinting experiments with nuclear extracts isolated from Douglas-fir megagametophyte identified two protein-protected sites, a 31-bp sequence locating in the -176/-146 region that contained two ACGT-core motifs, and a 12-bp sequence, 5'-TGCCACGGAAGG-3', of unknown function. To identify promoter regions responsible for the regulation of gPmMTa gene expression, a series of deletions in the 0.9-kb fragment of the gPmMTa promoter was fused to the uidA reporter gene and the chimeric gene constructs were assayed in Douglas-fir and transgenic tobacco. Transient expression assays in megagametophyte and zygotic embryos indicated that the sequence lying between -190 and +88 of gPmMTa was sufficient to drive the expression of the reporter gene and the 225-bp fragment (-677 to -453) contained sequences necessary for high level expression. The gPmMTa promoter was not active in the seeds of transgenic tobacco. / Graduate
7

Genetic variation in wood properties of Pinus caribaea from Fiji

Nuevo, C. C. January 1982 (has links)
No description available.
8

A comparison of selection and breeding strategies for incorporating wood properties into a loblolly pine (Pinus taeda L.) elite population breeding program

Myszewski, Jennifer Helen 30 September 2004 (has links)
The heritability of microfibril angle (MFA) in loblolly pine, Pinus taeda L., and its genetic relationships with height, diameter, volume and specific gravity were examined in two progeny tests with known pedigrees. Significant general combining ability (GCA), specific combining ability (SCA), and SCA x block effects indicated that there are both additive and non-additive genetic influences on MFA. Individual-tree narrow-sense heritability estimates were variable, ranging from 0.17 for earlywood (ring) 4 MFA to 0.51 for earlywood (ring) 20 MFA. Genetic correlations between MFA, specific gravity and the growth traits were non-significant due to large estimated standard errors. Multiple-trait selection and breeding in a mainline and elite population tree improvement program were simulated using Excel and Simetar (Richardson 2001). The effects of four selection indices were examined in the mainline population and the effects of seven selection indices and four breeding strategies were examined in the elite population. In the mainline population, selection for increased growth caused decreased wood quality over time. However, it was possible to maintain the overall population mean MFA and mean specific gravity at levels present in the base population by implementing restricted selection indices. Likewise, selection for improved wood quality in the elite population resulted in decreased growth unless restricted selection indices or pulp indices derived from those of Lowe et al. (1999) were used. Correlated phenotypic responses to selection on indices using economic weights and heritabilities were dependent on breeding strategy. When a circular mating system (with parents randomly assigned to controlled-crosses) was used, the index trait with a higher economic weight was more influential in determining correlated responses in non-index traits than the index trait with a lower economic weight. However, when positive assortative mating was used, the index trait with a greater variance was more influential in determining correlated responses in non-index traits than the index trait with a lower variance regardless of economic weight.
9

Local adaptation and genetic variation in south-western Australian forest trees : implications for restoration /

O'Brien, Eleanor K. January 2007 (has links)
Thesis (Ph.D.)--University of Western Australia, 2007.
10

The assessment of DNA barcoding as an identification tool for traded and protected trees in southern Africa : Mozambican commercial timber species as a case study

20 January 2015 (has links)
M.Sc. (Botany) / Global efforts to protect the world’s forests from unsustainable and inequitable exploitation have been undermined in recent years by rampant illegal logging in many timber-producing countries. A prerequisite for efficient control and seizure of illegally harvested forest product is a rapid, accurate and tamper proof method of species identification. DNA barcoding is one such a tool, relatively simple to apply. It is acknowledged to bring about accuracy and efficiency in species identification. In this study a DNA barcode reference library for traded and protected tree species of southern Africa was developed comprising of 81 species and 48 genera. Four primary analyses were conducted to assess the suitability of the core barcodes as a species identification tool using the R package Spider 1.2-0. Lastly, to evaluate this identification tool, query specimens independently sampled at a Mozambican logging concession were identified using DNA barcoding techniques. The nearest neighbour (k-NN) and best close match (BCM) distance based parameter yielded 90% and 85% identification success rate using the core plant barcodes respectively. DNA barcoding identification of query specimens maintained a constant 83% accuracy over the single marker dataset and the combined dataset. This database can serve as a backbone to a control mechanism based on DNA techniques for species identification and also advance the ability of relevant authorities to rapidly identify species of timber at entry and exit points between countries with simple, fast, and accurate DNA techniques.

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