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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

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.
2

Pollination and pollen and seed development in western hemlock

Colangeli, Anna Maria 12 November 2014 (has links)
Graduate
3

Development of a computerized seed orchard inventory-monitoring system and analysis of seed orchard productivity variables

Merkle, Scott Arthur January 1982 (has links)
A computer program package for use with the southern pine seed orchard Inventory-Monitoring System (IMS) was developed and tested using 1980 and 1981 cone crop data collected from Weyerhaeuser's loblolly pine seed orchard at Magnolia, Arkansas. The Computerized IMS, written in Fortran, is accompanied by a user's guide containing data entry instructions. The IMS package includes one predictive program and two programs designed to interpret actual harvest data and make it available for the computation of predictions for future crops. The predictive program utilizes strobilus survival data from sample trees and clonal estimates for cone analysis-derived variables to compute clonal cone and seed yield predictions. Cone yield predictions calculated by the Computerized IMS for the 1980 and 1981 crops indicated that it has the potential for producing useful production estimates. Investigations of variance within the seed orchard having an impact on IMS predictions centered on clonal, age-class (within-clone), annual, orchard location and with in-crown effects on cone analysis-derived variables, cone efficiency and flowers-per-tree. Analysis of clonal variance indicated that seed potential and germination efficiency were under strong genetic control compared to the other characters. Annual clonal stability was high enough for clonal seed potential and seed efficiency to make useful regression models possible for estimating these variables without complete cone analysis. Clonal cone efficiencies displayed low annual stability, discouraging the use of stratified clones to estimate productivity, since clones could change productivity classes from year to year. Within-crown variation was not well-defined for most variables due to clone-crown sector interaction. However, cones were concentrated in the middle one-third of the crown and empty seed percentages were found to be highest in the north crown quadrant. The study indicated that clone-by-clone monitoring of seed orchard production, while the most expensive option, will produce the most reliable and useful yield predictions. / Ph. D.
4

Klonal sarıçam (Pinus sylvestris L.) tohum bahçesinde tohum özellikleri için kalıtım derecesi /

Kaya, Canpolat. Bilir, Nebi. January 2008 (has links) (PDF)
Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Orman Mühendisliği Anabilim Dalı, 2008. / Bibliyografya var.
5

Markery fyziologického stavu borovice ve vztahu ke genetické variabilitě / Markers of pine physiological state in relation to genetic variability

Šafránková, Anna January 2016 (has links)
Breeding of coniferous trees in the Czech Republic is undergoing an important development during last decades, especially thanks to molecular-genetic methods, which refine and simplify mapping of tree genotypes and the selection of superior genotypes. Recently, in the Czech Republic superior genotypes are selected based on forestry parameters (tree height, trunk diameter, and timber quality) what does not always correlate with the ability of a tree to resist abiotic and biotic stresses. Recently, there is an effort to include in the breeding also physiological parameters and select superior genotypes using nonspecific stress indicators, which are able to correspond better to tree fitness than the forestry growth parameters. The present thesis deals with genotypes of Scots pine (Pinus sylvestris L.) growing in seed orchards Doubrava and Silov in the Pilsen region in the Czech Republic. Seed orchards are tree plantations, which serve as a reserve of the genetically valuable reproduction material, they are parts of breeding programs. Pine needles were collected in July 2015 and analyzed for non-specific stress indicators - photosynthetic pigments, phenolics, lignin, cellulose and proline contents and leaf reflectance and fast chlorophyll fluorescence measurements. First objective of the present thesis...
6

Fingerprinting of full and half-sib black wattle (Acacia mearnsii) progenies using Random Amplified Polymorphic DNA (RAPD).

Naguran, Riann. January 2005 (has links)
Black wattle (Acacia mearnsii), which belongs to the genus Acacia, is one of the many species of trees or hardwoods grown commercially in South Africa. Black wattle is a species indigenous to Australia and was introduced into South Africa by the van der Plank brothers in 1864. These trees are grown in South Africa because of its tannin-rich bark, the extract of which is used by the leather tanning industry. Black wattle is also grown for its timber, timber products and pulp. The introduction and cultivation history of black wattle suggests that the South African plantations contain limited genetic variation with relatedness amongst groups estimated to be high, thus implying a narrow genetic base in the South African black wattle population. In this investigation, Random Amplified Polymorphic DNA (RAPD) was used to estimate the genetic variation between seven different black wattle groups. A total number of 34 individuals obtained from different areas in South Africa were examined; Piet Retief (group 47 and 50: half-sibs), Kumbula (group 85: unrelated individuals), Howick (group 400: unrelated individuals) and an unknown area (groups 88, 89, 91: full-sibs). As this investigation was the first of its kind, a DNA isolation method as well as a PCR-RAPD protocol had to be modified. Total genomic DNA was successfully extracted using the CTAB DNA extraction method. This method removed large amounts of tannin present in the cells of the black wattle leaves and extracted high quality DNA to conduct between 50-100 RAPD reactions. The DNA purities ranged from 0.1 to 1.8, with an average of 1.46. A total of fourteen 10-mer RAPD primer sequences were randomly selected from the Operon Technologies primer list A, and tested in this investigation. Of the 14 primers used, only nine primers produced clear, single and repeatable bands. Therefore nine primers were selected for subsequent analyses. Ninety one loci that generated bands ranging from 300-3050 base pairs were produced. Seven to 13 loci per primer were generated. A total of 95.6 % of the loci were polymorphic. The overall expected mean heterozygosity (H = 0.3) obtained in this study was high in comparison to other studies conducted on acacias. The high levels of genetic variation were attributed to mating systems, dissortative mating and geographic distribution. The statistical packages POPGENE and ARLEQUIN were used to analyse the RAPD fingerprints. The genetic measures, Nei's diversity and Shannon's Information Index, showed that there was greater diversity exhibited (Nei's gene diversity = 32.09 % and Shannon's = 48.31 %), in the whole population than in each of the groups (with average of Nei's gene diversity = 20.33 % and Shannon's = 34.64 %). With regards to individual group analyses, low levels of genetic variation was obtained in group 400 (unrelated), from the Howick region, and group 85 (unrelated), from the Kumbula region, (mean 0.14 and 0.17 respectively). The low genetic values were attributed to limited gene exchange occurring in these two areas, bottlenecks and selection pressures. Groups 88, 89 and 91, from the unknown region (full-sib groups), were the most variable in comparison to the other groups, with means of (0.27,0.24 and 0.18 respectively). These high genetic variation values could be due to the fact that gene migration could have occurred between these groups and others in the area. It is thought that most acacias are insect-pollinated and this could have lead to gene migration between groups or populations, thereby explaining the high mean values. The gene flow obtained for the seven groups (FST = 0.174) indicated that great genetic differentiation existed in this population of black wattle studied. This value is higher in comparison to other woody species; however it is similar to other acacia species. UPGMA cluster analysis using Nei's unbiased genetic distance, revealed four distinct clusters of groups corresponding to the distribution areas represented in this study. The Howick (group 400: unrelated) and Kumbula (group 85: unrelated) were more closely related to each other than to the other groups, since both these groups are from Natal. The Piet Retief groups (groups 47 and 50: half-sibs), branched-off together, indicating that they are distinct from the other groups. The pairwise analysis of identity showed that the relationship between the group from Howick (group 400: unrelated) and all the other groups from the other regions was the lowest, ranging from 64 % to 79 %. The relationship between all the groups beside the group from Howick (group 400: unrelated) was reasonably high, ranging from 78 % to 90 %. This distance displayed by group 400 (unrelated) from Howick in relation to the groups, is attributed to the fact that it is frost resistant and the other groups not. Genetic variation was also detected and partitioned, between and within groups, by Analysis of Molecular Variance (AMQVA). Majority of the variation existed within groups (82.65 %) but significant differentiation was recorded between groups (17.44 %). This high level of within group differentiation may be explained by many aspects, such as the species breeding system, genetic drift or genetic isolation of groups or populations. The application of RAPD fingerprinting in black wattle has provided a more in depth understanding of the genetic variation residing in the South African population. The results achieved implementing this technique has shown that significant genetic variation exists within the black wattle population in South Africa. The results obtained in this study are also important since it is contrary to the expectation that the black wattle population in South Africa has low genetic variation. This knowledge is of great value to genetically discriminate between individuals or groups, to improve the selection of superior genotypes and allowing improved quality control in breeding programmes and seed orchard management. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
7

Využití laboratorní a obrazové spektroskopie pro hodnocení odolnosti borovice lesní vůči suchu a rozlišení jejich ekotypů / Use of laboratory and image spectroscopy to evaluate drought resistance of Scots pine and to distinguish its ecotypes

Raasch, Filip January 2021 (has links)
The aim of this study was to propose a non-destructive method for measuring Pinus sylvestris seedlings, to determine whether water stress would be evident in laboratory spectra of pines, to compare whether the response of pines would differ by ecotype, and to investigate whether two ecotypes of Pinus sylvestris could be distinguished using laboratory and image spectroscopy. For these purposes, hyperspectral images of seed orchards from August 2020 were processed and a three-month laboratory experiment was conducted, in which stress from water deficit was induced in two-year-old pine seedlings from the upland and hilly ecotypes. Spectral data were analysed using mixed statistical models, analysis of variance, principal component analysis, training of supervised pixel classifiers, vegetation indices, and linear regression. Based on the analyses, it was found that water stress can be detected in severely stressed Pinus sylvestris seedlings. The most sensitive spectral bands to water content were observed in the region between 1000-2500 nm. The initial response to water stress did not differ by ecotype, but a faster recovery was observed at the upland ecotype after the period of draught. The two Pinus sylvestris ecotypes were distinguished with high accuracy from both laboratory and image spectral...

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