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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

Synthetic seed production for germplasm storage of Hydrastis canadensis L. (goldenseal)

Settipalli, Satyaprakash R. January 2007 (has links)
Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains vii, 48 p. : col. ill. Includes abstract. Includes bibliographical references (p. 40-42).
2

Conservation of genetic resources : costs and implications for a sustainable utilization of plant genetic resources for food and agriculture /

Virchow, D. January 1999 (has links)
Thesis (doktorgrades)--Christian-Albrechts-Universität zu Kiel, 1998. / Includes bibliographical references (p. [225-239) and index.
3

Variação, parâmetros genéticos e seleção entre e dentro de procedências e progênies de Handroanthus vellosoi (Toledo) Mattos

Batista, Camila Moreira [UNESP] 09 February 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-09Bitstream added on 2014-06-13T20:19:52Z : No. of bitstreams: 1 batista_cm_me_ilha.pdf: 351886 bytes, checksum: 7a32bba46398f3b30fabc1d91c4aac59 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A intensa fragmentação dos habitats de ocorrência de Handroanthus vellosoi (Toledo) Mattos já extinguiu grande parte das populações naturais da espécie. Essa exploração inadequada vem comprometendo sua capacidade de sobrevivência nesses ambientes naturais. Neste contexto, as finalidades deste trabalho são a conservação ex situ, avaliação da variabilidade e estimativa de parâmetros genéticos em teste de procedências e progênies de polinização aberta da espécie arbórea tropical Handroanthus vellosoi por caracteres quantitativos. Mais especificamente, pretende-se estudar a herança de caracteres quantitativos, a correção entre estes caracteres e selecionar árvores superiores de H. vellosoi em um teste de procedências e progênies para a produção de sementes com ampla variabilidade genética para fins de recuperação ambiental. O teste foi instalado na Estação Experimental de Luiz Antônio, do Instituto Florestal de São Paulo em 1986. O delineamento experimental adotado foi o de blocos de famílias compactas, com seis repetições, com subparcelas lineares de cinco plantas provenientes de duas procedências, 17 progênies de polinização aberta de Bebedouro e 18 de Mogi Guaçu, obedecendo ao espaçamento de 3 x 3 m. O ensaio foi mensurado aos 24 anos de idade para diâmetro à altura do peito, altura de planta, volume, forma do fuste e sobrevivência. Para as análises estatísticas foi utilizado o programa estatístico SAS. As estimativas da diferenciação genética entre e dentro de procedências e progênies indicou que a maior parte da variação genética se encontra entre progênies / he intense fragmentation to of the habitat that Handroanthus vellosoi (Toledo) Mattos occur has extinguished much of the natural populations of the species. This exploitation is inadequate, compromising their ability to survive in these natural environments. In this context, the purposes of this study was the ex situ conservation, evaluation and estimation of the genetic variability and parameters in a open-pollinated provenance and progeny test of the tropical tree species Handroanthus vellosoi, based on quantitative traits. More specifically, we intend to study the inheritance of quantitative thaits, the correction between traits and to select superior trees of H. vellosoi for to seed production with wide genetic variability for environmental remediation. The provenance and progeny test was established in 1986 at the Experimental Station of Luiz Antônio, São Paulo Forestry Institute. The trial was established in a compact family block desing with six replicates, linear plots of five plants, using two provenances, 17 families from Bebedouro and 18 from Mogi Guaçu. The spacing used was the 3 x 3 m. The test was measured at 24 years of age to diameter at breast height (DBH), plant height, volume, stem forma and survival. The statistical analysis was performed using the SAS program. The estimates of genetic differentiation between and within provenances and progenies indicated that most of the genetic variation is found among progenies
4

Génétique des populations et modèles d'architecture et de production végétale : application à la préservation des ressources génétiques des Mascarocoffea / Population genetics and architectural-functional plant growth models : application to Mascarocoffea (coffee trees natives from Madagascar) genetic resources preservation

Andrianasolo, Domohina Noromalala 14 December 2012 (has links)
Les espèces de Mascarocoffea (61 sur 124 décrites endémiques de Madagascar) sont fortement menacées d'extinction à cause de la réduction considérable des surfaces forestières à Madagascar. En vue de leur préservation, l'évaluation du niveau de diversité dans la collection de Mascarocoffea de la station de Recherche du FOFIFA à Kianjavato comparé à celui de quatre populations en in situ a été faite. Le niveau de diversité des populations en collection est plus important que celui en in situ dont l'hétérozygotie observée est similaire avec une importante richesse allélique. La modélisation de la croissance et du développement des jeunes individus de ces populations par le modèle GreenLab a permis d'appréhender la mise en place de la structure de la plante en accord avec la variabilité architecturale interspécifique chez les populations étudiées à différents stades de développement. Un bon ajustement sur la croissance a été obtenu par la calibration des populations étudiées dans le dispositif expérimental. L'évolution de la variable clé du modèle GreenLab, le rapport source-puits (Q/D) en fonction du temps pour les 7 populations ajustées a montré que la production de beaucoup plus d'organes influence l'évolution du rapport Q/D au court du temps. Ce rapport affecte la taille des organes et l'architecture des Mascarocoffea. Un essai sur des individus adultes poussant dans des milieux différents (ex et in situ) dont les paramètres morphologiques, architecturaux et génétiques ont été déterminés dans cette étude, permettrait de déterminer la réponse des plantes selon l'environnement dans lequel elles poussent et de faire une optimisation du modèle. La détection des individus hybrides aussi bien in situ qu'en collection permet de voir ultérieurement la conséquence sur la structure de la plante et d'envisager d'intégrer les paramètres génétiques dans le modèle…. / Mascarocoffea species (61 / 124 described, endemics to Madagascar) are highly endangered because of the considerable Madagascar area forest reduction. For their preservation, assessment of the Mascarocoffea diversity level in the FOFIFA Kianjavato Collection Research Station compared to four in situ populations was made. The collection population's diversity level is larger than that in situ, observed heterozygosity is similar with a significant allelic richness. Modeling the young individuals in these populations' growth and development by the GreenLab model helped to understand the development of the plant structure in accordance with the interspecific architectural variability in studied populations at different development stages. A good fitting on growth was obtained on the populations studied in the experimental plot. The evolution of the GreenLab model key variable, the source-sink ratio (Q / D), showed that the production of many more organs influences the ratio Q / D evolution in time. This variable affects organ size and Mascarocoffea architecture. An essay on adult individuals growing in different environments (in and ex situ), whose morphological, genetic and architectural parameters were determined in this study, would allow the plants response in terms of architecture depending on the environment in which they grow and to optimize the model. The detection of hybrid individuals in both in situ and at the collection would detect hybrids characters on the plant structure and consider integrating genetic parameters in the model....
5

Die völkerrechtlichen Regelungen über den Zugang zu genetischen Ressourcen /

Lochen, Tobias. January 2007 (has links)
Thesis (doctoral)--Universität, Gfiessen, 2007. / Includes bibliographical references (p. [287]-303) and index.
6

Gain and diversity in multi-generation breeding programs /

Andersson, Erik W., January 1900 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
7

Genetic resources for disease resistance breeding in wheat : charaterization and utilization /

Hysing, Shu-Chin. January 2007 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniversitet, 2007. / Härtill 5 uppsatser + 3 appendix.
8

Genetic diversity and oil quality of Guizotia Cass. (Asteraceae) /

Petros, Yohannes, January 2008 (has links) (PDF)
Diss. (sammanfattning) SLU, Alnarp : Sveriges lantbruksuniversitet, 2008. / Härtill 4 uppsatser.
9

Variação, parâmetros genéticos e seleção entre e dentro de procedências e progênies de Handroanthus vellosoi (Toledo) Mattos /

Batista, Camila Moreira. January 2012 (has links)
Orientador: Miguel Luiz Menezes Freitas / Coorientador: Mario Luiz Teixeira de Moraes / Banca: Alexandre Magno Sebbenn / Banca: Ananda Virgínia de Aguiar / Resumo: A intensa fragmentação dos habitats de ocorrência de Handroanthus vellosoi (Toledo) Mattos já extinguiu grande parte das populações naturais da espécie. Essa exploração inadequada vem comprometendo sua capacidade de sobrevivência nesses ambientes naturais. Neste contexto, as finalidades deste trabalho são a conservação ex situ, avaliação da variabilidade e estimativa de parâmetros genéticos em teste de procedências e progênies de polinização aberta da espécie arbórea tropical Handroanthus vellosoi por caracteres quantitativos. Mais especificamente, pretende-se estudar a herança de caracteres quantitativos, a correção entre estes caracteres e selecionar árvores superiores de H. vellosoi em um teste de procedências e progênies para a produção de sementes com ampla variabilidade genética para fins de recuperação ambiental. O teste foi instalado na Estação Experimental de Luiz Antônio, do Instituto Florestal de São Paulo em 1986. O delineamento experimental adotado foi o de blocos de famílias compactas, com seis repetições, com subparcelas lineares de cinco plantas provenientes de duas procedências, 17 progênies de polinização aberta de Bebedouro e 18 de Mogi Guaçu, obedecendo ao espaçamento de 3 x 3 m. O ensaio foi mensurado aos 24 anos de idade para diâmetro à altura do peito, altura de planta, volume, forma do fuste e sobrevivência. Para as análises estatísticas foi utilizado o programa estatístico SAS. As estimativas da diferenciação genética entre e dentro de procedências e progênies indicou que a maior parte da variação genética se encontra entre progênies / Abstract: he intense fragmentation to of the habitat that Handroanthus vellosoi (Toledo) Mattos occur has extinguished much of the natural populations of the species. This exploitation is inadequate, compromising their ability to survive in these natural environments. In this context, the purposes of this study was the ex situ conservation, evaluation and estimation of the genetic variability and parameters in a open-pollinated provenance and progeny test of the tropical tree species Handroanthus vellosoi, based on quantitative traits. More specifically, we intend to study the inheritance of quantitative thaits, the correction between traits and to select superior trees of H. vellosoi for to seed production with wide genetic variability for environmental remediation. The provenance and progeny test was established in 1986 at the Experimental Station of Luiz Antônio, São Paulo Forestry Institute. The trial was established in a compact family block desing with six replicates, linear plots of five plants, using two provenances, 17 families from Bebedouro and 18 from Mogi Guaçu. The spacing used was the 3 x 3 m. The test was measured at 24 years of age to diameter at breast height (DBH), plant height, volume, stem forma and survival. The statistical analysis was performed using the SAS program. The estimates of genetic differentiation between and within provenances and progenies indicated that most of the genetic variation is found among progenies / Mestre
10

Genetic and phenotypic characterisation of the South African Namaqua Afrikaner sheep breed

Qwabe, Sithembile Olga 25 July 2012 (has links)
Genetic and phenotypic characterisation is essential for the conservation and utilisation of farm animal genetic resources, especially indigenous types that are often disregarded due to lower production potential compared to commercial breeds. In this study a genetic characterisation was performed on 144 Namaqua Afrikaner sheep kept at the Karakul Experimental Station (KES) and Carnarvon Experimental Station (CES) and a private farm Welgeluk (WGK) using 22 ISAG recommended microsatellite markers. Results of this study showed that the mean number of alleles were low (3.6 for KES to 4.2 for WGK) for the loci tested. Heterozygosity values across loci ranged between 46% for WGK, 48% for KES and 55% for CES, indicating low to moderate genetic variation within the different populations. The AMOVA analyses revealed that 89.5% of the genetic variation in the breed was due to the differences within populations and 10.5% due to differences between populations. The genetic distance estimates revealed a close relationship between the CES and WGK populations. The population structure confirmed the differentiation of three clusters with relationships between the CES and WGK populations. Phenotypic characterisation of the breed was limited to the Carnarvon flock, where production and morphological data were recorded. Morphological measurements indicated an average body length of 71.2 cm and 68.7 cm for rams and ewes respectively. Over 60% of the sheep had their tail twisted to the left. The molecular data provided by this study will serve as a reference for genetic management and breeding strategies of the indigenous Namaqua Afrikaner sheep. Copyright / Dissertation (MSc(Agric))--University of Pretoria, 2011. / Animal and Wildlife Sciences / unrestricted

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