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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.
171

Forging a New Global Commons Introducing common property into the global genetic resource debate.

Mason, Nicholas Craig January 2004 (has links)
This thesis provides an analysis of recent attempts to regulate the governance of genetic resources through the initiation of new global commons regimes. These attempts have arisen out of a combination of the growing recognition of genetic resources' value and global nature; a new resurgence in support for the common property paradigm; and, during a period in which the world is becoming increasingly globalised, with many governance competencies moving to the supranational level. They can be viewed as part of a broader effort to proffer the common property approach as a legitimate alternative in the property regime debate: a debate that has increasingly become trapped in the public-private dichotomy at the dawn of the twenty-first century. The aim of this thesis is to investigate the success of these attempts, and offer suggestions about how future attempts might be more successful. While there are a multitude of books, articles, opinion pieces and media reports produced that concern themselves with property theory, intellectual property theory, the efficacy or morality of applying property regimes to living materials, and the threats and promises of globalisation, all of which influence the notion of a potential global genetic commons, relatively little has been written directly on the idea of applying global common property regimes to genetic resource governance issues. The first part of this thesis constructs a theory of a global genetic commons, drawing inspiration from a variety of sources, while the second part tests this theory in order to analyse the outcomes of the recent attempts, and suggest directions for future research. The thesis finds that the conception of a global genetic commons is indeed a valid one, and that while not all attempts so far have been successful, the common property paradigm does offer valuable insights for the future governance of genetic resources at the global level.
172

Danos e biologia de Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) em genótipos de milho. / Damage and biology of Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: noctuidae) on maize genotypes.

Romildo Cássio Siloto 29 November 2002 (has links)
A utilização de variedades resistentes é uma importante ferramenta no manejo integrado de pragas e vem sendo valorizada nos programas de melhoramento de plaritas. Neste estudo foram avaliados 12 genátipas de milho, em relação aos danos causados por Spodoptera frugiperda (J.E. Smith, 179r7) em condições de campo, e em relação ao efeito desses genófípos na biologia da praga, em condições de laboratório. Os experimentos de campo foram realizados nos municípios de Casa Branca, Florínea e Miguetópotis/Guaíra, representando três diferentes regiões do Estado de São Pauto. As plantas foram avaliadas nas idades de 6 a 8 e de 10 a 12 folhas, através de uma escala de notas de O a 9. Os resultados da anáfíse de varíãncía mostraram que os danos causados pela lagarta-do-cartucho nos genótipos de milho foram diferentes nos três locais avaliados. A interação idade*local foi significativa, indicando que, dependendo do local avaliado, os danos foram diferentes em cada idade. Na idade de 6 a 8 folhas, os danos foram significativamente menores em Casa Branca em relação à Florínea e à Miguelápolis/Guaíra. Na idade de 10 a 12 folhas, os três locais apresentaram danos significativamente distintos. Miguelápolis/Guaíra foi o local que apresentou menos -úanos, em relação à r'lorínea. Casa Branca foi o local em que ocorreu mais danos. Na comparação das médias entre as idades em cada local, Casa Branca apresentou os menores danos na idade de 6 a 8 folhas, enquanto que, em Florinea e iviiguetópolis/Guaíra, isso ocorreu na idade de 10 a 12 folhas. Corri base na analise -úe agrupamento para os experimentos de campo, os genótipos Z 8486, C 333 B e Diria 766 formaram o grupo daqueles menos danificados, enquanto que os genótipos XL 212 e Piranão formaram o grupo dos mais danificados peia iagarta-do-cartucho. Houve pouco efeito dos genótipos avaliados sobre a biologia do inseto. Nos experimentos de laboratório, os genótipos Z 8486 e Master proporcionaram menor peso de lagartas aos 7 e 14 dias, em relação aos genótipo XL 212, enquanto em Z 8486 e IAC-Vitória ocorreu menor viabilidade larval em relação à Dina 766. O genótipo Dina 766, que ficou entre os menos danificados em condições de campo, proporcionou maior peso larval aos 7 dias e maior viabilidade larval. / Plant resistance is a usefui component of integrated pest management and its value has been increasing in plant breeding programs, ln this study, 12 maize genotypes were evaluated to damage of fali armyworm Spodoptera frugíperda (J.E. Smith, 1797) in field conditions. The effect of these genotypes on fali armyworm biology was evaluated in laboratory conditions. The field experiments were carried out in Casa Branca, Florínea and Miguelópolis/Guaíra, whích represent three different regions of São Paulo State. The plants were evaluated at 6-8 and 10-12 exposed leaves, using a rank scale from O to 9. The analysis of variance showed that the fali armyworm damage on maize genotypes differed in each of three places. The interaction age*piace was significant and it indicares that the damage differed according to the age of the plants, depending on where they were evaluated. At 6-8 leaf stage, the damage were less significant in Casa Branca comparing to Florínea and Miguetópolis/Guaíra. At 10-1 2 leaf stage, the three places showed damage with significant differences. Migueiópolis/Guaíra was the place with fewer damage, comparing to Florínea. ln Casa Branca occurred more damage. Comparing the age average of the plants in each region, the plants in Casa Branca showed fewer damage at 6-8 leaf stage whereas the plants in Florinea and Miguelópolis/Guaíra showed it at 10-12 leaf stage. ln the field experiments, the Cluster Analysis showed that Z 8486, C 333 B and Dina 766 genotypes set the group wíth fewer fali armyworm damage whereas XL 212 and Piranão genotypes set the most damaged group. The genotypes provided littie effect on fali armyworm biology. ln the laboratory experíments, the larvae reared on Z 8486 and Master genotypes provided lower weight on days 7 and 14, when compadng to XL 212. The genotypes Z 8486 and IAC-Vitória presented lower larval survival when comparing to Dina 766. The larvae reared on Dina 766 genotype provided the highest weight for day 7 and the greatest larval survival, even though, this genotype was one of the least damaged in the field.
173

Caracterização genética de populações de cupuaçuzeiro, Theobroma grandiflorum (Willd. ex. Spreng.) Schum., por marcadores microssatélites e descritores botânico-agronômicos. / Genetic characterization of cupuassu theobroma grandiflorum (willd. ex. spreng.) schum. populations by microsatellite markers and botanic-agronomic descriptors.

Rafael Moyses Alves 05 February 2003 (has links)
Este trabalho teve por objetivo caracterizar e comparar a estrutura genética de sete populações de cupuaçuzeiro, Theobroma grandiflorum (Willd. ex Spreng.) Schum., uma fruteira nativa da Amazônia brasileira, utilizando marcadores microssatélites e descritores botânico-agronômicos. Visou também conhecer, preliminarmente, o sistema reprodutivo do cupuaçuzeiro. A estrutura genética das sete populações, sendo três populações naturais, coletadas na suposta área de máxima diversidade da espécie, três populações estabelecidas em Banco Ativo de Germoplasma (BAG), e uma população coletada em plantios comerciais do município de Tomé açu - PA, foi analisada com auxílio de marcadores microssatélites. Foi observada alta variabilidade genética na espécie, ressaltado pelo elevado número de alelos por loco, alto nível de heterozigosidade e divergência entre as populações. A divergência foi mais acentuada entre as populações naturais, em comparação com as populações do Banco de Germoplasma. Essa divergência pode indicar um processo preliminar de diferenciação. Porém, foi mais acentuada entre as populações oriundas de Tucuruí e Nova Ipixuna, corroborando com as indicações que consideram essa região como o centro de máxima diversidade de T. grandiflorum. Estes resultados sugerem, como estratégia de conservação in situ, a necessidade de definição de mais de um local para reserva genética, bem como, em relação a conservação ex situ, as coletas devem ser realizadas em vários locais. A elevada diversidade genética observada nos plantios comerciais, permite recomendar essas plantações como uma fonte alternativa de genes e genótipos ao programa de melhoramento de T. grandiflorum. No BAG foi observada baixa divergência genética entre as populações, sendo que, a maior parte da variabilidade genética encontrava-se dentro das populações. Essa caracterização foi complementada com o emprego de descritores botânico-agronômicos, quando foi observada grande variabilidade para a maioria dos descritores empregados. Houve necessidade, inicialmente, de selecionar dentre as 53 variáveis, aquelas que melhor se prestavam para a caracterização dos acessos. Empregando análises univariada e multivariada por componentes principais, foi possível descartar 64% das variáveis iniciais, sendo sugerida uma lista mínima de 19 descritores para o cupuaçuzeiro. Com base nessa lista e o emprego da distância Euclideana média, foi obtida uma matriz de dissimilaridade entre os 31 acessos avaliados. Esses acessos foram agrupados pelo método de Tocher e UPGMA, tendo sido obtidos seis grupos de similaridade. A comparação entre as duas caracterizações realizadas no BAG, revelou uma correlação positiva e significativa entre distâncias genéticas e fenotípicas. Preliminarmente foi estudado o sistema de reprodução do cupuaçuzeiro, numa população natural de Nova Ipixuna – PA, sendo utilizadas oito progênies de polinização aberta, com dez indivíduos e oito locos microssatélites polimórficos. Baseado na estimativa da taxa de cruzamento multilocos ( $ t m =1,0) e individual por planta materna, o estudo nessa população sugere que o T. grandiflorum é uma espécie predominantemente alógama, com uma pequena percentagem (5,4%) de cruzamentos entre parentes. Esse fator tem implicações importantes nas estratégias de conservação in situ e na utilização de progênies oriundas de polinização aberta nos programas de melhoramento. / This work had the objectives to characterize and compare the genetic structure of seven populations of cupuassu, Theobroma grandiflorum (Willd. ex Spreng.) Schum., a fruit tree native to the Brazilian Amazon using microsatellite markers and botanic-agronomic descriptors; and to investigate the cupuassu mating system. The genetic structure of seven populations of cupuassu, with three originally collected at the putative center of maximum diversity of the species; three populations established at the active germplasm collection (BAG); and one population colected from commercial plantings were analyzed using microsatellite markers. High genetic variability was observed for the species, demonstrated by the elevated number of alleles per locus; high heterozigosity and divergence between populations. The divergence was more noticeable among natural populations than among populations from the germplasm collection. This divergence might indicate a preliminary process of diversification. However, it was more pronounced between the populations from Tucuruí and Nova Ipixuna, corroborating indications that this region is considered the center of maximum diversity of T. grandiflorum. These results suggested as strategy for in situ conservation, the requirement to define more than one site for genetic reserves, large enough to maintain rare alleles in the medium- to long term. For ex situ conservation, sample collection must be conducted in many sites, with low intensity in each site, due to the existing variability witihin population. The high genetic diversity observed in commercail plantings allow to recommend these areas as an alternative source for genes and genotypes for the breeding program of T. grandiflorum. The characterization of the germplasm populations was complemented using botanic-agronomic descriptors. The large observed variability for most of the evaluated descriptors indicated that the germplasm collection contained high phenotypic diversity. Initially, it was necessary to select from the 53 evaluated variables, those most suitable for characterization of the accessions. Using univariate and multivariate analyses of principal components, it was possible to discard 64% of the initial variables, and a minimum descriptor list with 19 traits was proposed for cupuassu. Based on the minimum descriptor list, a matrix of dissimilarity was constructed using Euclidean distances. The 31 evaluated cupuassu accessions were grouped using Tocher and UPGMA, into six groups. The comparison betwen the molecular and phenotypic characterization revealed a significant and positive correlation between the genetic and phenotypic distances. The mating system fo cupuassu was studied, based on a natural population from Nova Ipixuna – PA, using eight progenies derived from open-pollinated pods with ten individuals each and eight polymorphic microsatellite loci. Based on the estimation of the multilocus outcrossing rate ( $ t m =1,0) and individual outcrossing rate ( $ t =1.0), the results from this population suggested that T. grandiflorum is a predominatly outbreeding species, with a small percentage (5,4%) of biparental inbreeding. These results have important implications on the in situ conservation strategies and on the use of open-pollinated progenies in breeding programs.
174

Avaliação de progênies F2:4 de uma população de soja e perspectivas de melhoramento / Evaluation of F2:4 progenies of a soybean population and breeding perspectives

Guilherme José Farias 21 January 2009 (has links)
Os objetivos do presente trabalho compreenderam a obtenção de estimativas de parâmetros genéticos e fenotípicos, como variâncias, correlações, herdabilidades e respostas à seleção, em uma população derivada do cruzamento entre as linhagens 14 e 56 de soja, contrastantes para produção de grãos. Os tratamentos consistiram de uma amostra de 89 progênies F2:4 e 11 testemunhas comerciais, que foram avaliadas em experimentos em látice triplo 10 x 10 no ano agrícola 2007/08 na Estação Experimental Anhembi do Departamento de Genética da ESALQ/USP, localizada em Piracicaba, SP. A parcela experimental foi constituída de uma linha de 2 m de comprimento, espaçada de 0,5 m, contendo 35 plantas no estande ideal, após o desbaste. Foram avaliados os seguintes caracteres: dias até a maturação (DM), altura das plantas na maturação (AM), acamamento (AC) e produção de grãos (PG). As estimativas dos coeficientes de herdabilidade entre médias de progênies foram: elevada para AM (77,4%), mediana para DM (32,3%) e baixas para AC e PG (18,1% e 19,0%, respectivamente). Entretanto, os coeficientes de variação genética foram muito baixos para DM e AC (0,37% e 1,61%, respectivamente), e mais altos para AM e PG (6,80% e 6,83%, respectivamente), indicando a ocorrência de pouca variabilidade genética para DM e AC e, conseqüentemente, poucas perspectivas de resposta à seleção. O coeficiente de correlação genética entre AM e PG foi alto (rg = 0,67), indicando que a seleção para PG deve resultar em plantas mais altas. A estimativa da resposta com seleção das 20% progênies mais produtivas foi de 4,5%, e a resposta correlacionada em AM foi de 3,8%. Devido à baixa variabilidade genética, as respostas correlacionadas esperadas em DM e AC foram muito pequenas. Os resultados indicam que a população pode ser melhorada somente para os caracteres PG e AM. / This paper was carried out in order to estimate genetic and phenotypic parameters, such as variances, heritabilities, correlations and expected response to selection in a population derived from the cross between inbred lines 14 and 56 of soybeans, divergent for grain yield. Entries consisted of a sample of 89 F2:4 progenies and 11 commercial checks, evaluated in a triple 10 x 10 lattice design in the 2007/08 growing season at Anhembi Experimental Station of the Genetics Department (ESALQ/USP), near Piracicaba, SP. Plots were single 2-meter-long rows spaced 0.5 m apart, with 35 plants after thinning. The following traits were evaluated: days to maturity (DM), plant height at maturity (AM), lodging (AC) and grain yield (PG). Heritability estimates on a progeny mean basis were high for AM (77.4%), medium for DM (32.3%) and low for AC and PG (18.1% and 19.0%, respectively). However, genetic coefficients of variation were very low for DM and AC (0.37% and 1.61%, respectively) and higher for AM and PG (6.80% and 6.83%, respectively), which indicates low genetic variability for DM and AC and, consequently, small perspectives of response to selection. Genetic correlation coefficient between AM and PG was high (rg = 0.67), indicating that selection for higher PG will result in taller plants. Expected response based on selection of the 20% high yielding progenies was 4.5%, and the correlated response in AM was 3.8%. The correlated response in DM and AC were very low, due to the low genetic variability. General results have shown that the population can be improved only for the traits PG and AM.
175

Privatiseringen av de växtgenetiska allmänningarna : Konsekvenserna av regimkomplexet kring växtgenetiska resurser för bönders rättigheter och matsäkerhet

Ulaner, Magnus January 2007 (has links)
This thesis discusses the global regime complex concerning the management of plant genetic resources for food and agriculture, and how different regimes concerning these resources cooperate or stand in opposition to each other. Because of changes in US patent law and the establishment of TRIPS, patent claims over plant genetic resources has increased dramatically globally. This, amongst other things, in turn has lead to the development of CBD which in turn lead to the creation of access and benefit laws in many countries. To create a free flow of genetic resources for food and agriculture the ITPGRFA, with its multilateral system, were negotiated. The aim of this thesis is to investigate which consequences the regime complex concerning plant genetic resources for food and agriculture can have on the rights of small farmers, agricultural research and food security in the global South. The thesis shows how patents and strict access laws creates a situation where more and more actors has exclusive rights which excludes others from using these, for the global food security, essential resources. Further it is shown that there also are processes going on within the UPOV that risk to take away farmers right to save seeds, and thereby make them dependent on the more and more monopolistic global seed markets dominated by a few multinational corporations. It is established that ITPGRFAs multilateral system is an opening in this hyperownership of plant genetic resources for food and agriculture; but that the international community at the same time has to see to that the patent claims on plant genetic resources not violate farmers’ rights to their resources. / Denna uppsats behandlar det globala regimkomplexet för förvaltningen av växtgenetiska resurser för livsmedel och jordbruk, samt hur avtalen rörande dessa resurser samverkar eller står i motsättning till varandra. I och med förändringar i amerikansk patentlagstiftning och upprättandet av TRIPS har patentanspråk på växtgenetiska resurser ökat dramatiskt, vilket i sin tur påverkade tillkomsten av CBD vilken innefattar upprättandet av lagstiftning rörande tillträde till och den rättvisa fördelningen av nyttor härstammande från, genetiska resurser. För att möjliggöra ett relativt fritt flöde av växtgenetiska resurser har ITPGRFA med dess multilaterala system fram förhandlats. Syftet med denna uppsats är att undersöka vilka konsekvenser den nuvarande globala förvaltningen av växtgenetiska resurser för livsmedel och jordbruk kan få för jordbruksforskning, småbönders rättigheter och matsäkerhet i Syd. Uppsatsen visar på hur patent och tillträdeslagstiftningar skapar en situation där fler och fler parter innehar rättigheter att utestänga andra från att nyttja dessa, för den globala matsäkerheten, essentiella resurser. Vidare visas på hur det samtidigt pågår processer inom UPOV som riskerar att undanta bönder rätten att spara utsäde och därmed göra dem beroende av de i allt högre grad monopolartade frömarknaderna, vilka domineras av att fåtal multinationella företag. Här konstateras även att ITPGRFAs multilaterala system är en öppning i detta hyperägande, men att det internationella samfundet samtidigt måste försäkra att patentanspråk inte kränker bönders rättigheter till sina resurser.
176

Rural Homegardens in Central Sulawesi, Indonesia: An Example for a Sustainable Agro-Ecosystem? / Ländliche Hausgärten in Zentral-Sulawesi, Indonesien: Ein Beispiel für ein nachhaltiges Agrar-Ökosystem?

Kehlenbeck, Katja 15 May 2007 (has links)
No description available.
177

The economics of exchanging and adopting plant genetic resources for food and agriculture / Evidence from Germany and Peru

Lüttringhaus, Sophia 09 March 2022 (has links)
Landwirtschaftliche Systeme müssen sich immerfort an Druckfaktoren wie Klimawandel und Bevölkerungswachstum anpassen. Hierbei spielt die genetische Vielfalt von Pflanzen eine wichtige Rolle, da diese für die Sicherung der Ernährung und des Einkommens von entscheidender Bedeutung ist. Dennoch wird der wirtschaftliche Wert pflanzengenetischer Ressourcen selten untersucht. Um diese Forschungslücke zu schließen, werden in dieser Arbeit drei Bewertungen vorgestellt, welche die wirtschaftlichen Werte pflanzengenetischer Ressourcen untersuchen. Im Rahmen dieser Dissertation werden zwei verschiedene Agrarsystemen analysiert. Diese unterscheiden sich hinsichtlich des Klimas, der agrarökologischen Bedingungen, der landwirtschaftlichen Praxis, der politischen und ökonomischen Rahmenbedingungen sowie der soziokulturellen Verankerung der Kulturart. Die ersten beiden Analysen befassen sich mit der Züchtung und Produktion von Winterweizen in Deutschland. Charakterisiert sind diese durch ein gemäßigtes Klima und intensive Anbaubedingungen. In diesem System überwiegen moderne Sorten, die in einem formalisierten Züchtungsprozess entstanden sind. Es werden die folgenden Forschungsfragen beantwortet: 1) Was ist der ökonomische Wert, der durch den Austausch von Zuchtmaterial entsteht? und 2) Wie hoch ist der mikroökonomische Wert von Resistenzzüchtung? In der dritten Analyse wird ein weiteres Agrarsystem vorgestellt: Die Andenlandwirtschaft, wo im Hochland unter extensiven Bedingungen eine Vielzahl von Kartoffellandrassen angebaut wird. Dort wird folgende Frage analysiert: 3) Welche Mehrwerte wurden durch die Repatriierung oder Neuverteilung von Kartoffellandrassen erzielt? Diese Analysen zeigen, dass die Verfügbarkeit, der Austausch und die Nutzung von pflanzengenetischen Ressourcen die Agrarproduktion verbessern; es entstehen sowohl sektorale, mikroökonomische als auch ernährungsbezogene und kulturelle Mehrwerte. / Agricultural systems must constantly adapt to pressuring events such as climate change and population growth to maintain and improve production processes in a sustainable manner. Thereby the genetic diversity of plants used in agriculture constitute a strategic asset. Nevertheless, their economic value is often overlooked. To fill this research gap, this thesis presents three assessments that produce more evidence on the economic value of plant genetic resources. Two very distinct agricultural systems are discussed. These differ greatly in terms of climate, agroecological conditions, farming practices, seed systems, political and economic frameworks, and the socio-cultural embeddedness of the crop in question. The first two assessments are concerned with winter wheat (Triticum aestivum) breeding and production in the temperate climate and intensive growing conditions in Germany. Modern cultivars created in a formalized breeding process prevail in this system. The following two research questions are elaborated: 1) What is the economic value of exchanging breeding material? and 2) What is the microeconomic value of resistance breeding? The third assessment presents a different agricultural system: Andean agriculture, where a wide variety of potato landraces (Solanum spp.) are grown extensively in the Peruvian highlands. In this case, the research question I investigated is: 3) What are the benefits of repatriating (i.e., redistributing) potato landraces to Andean farmers? These studies demonstrate that the availability, exchange, and adoption of plant genetic resources, which are well adapted to and culturally embedded in specific agricultural systems, improve the overall quantity and sustainability of agricultural production. These improvements can be translated into sectoral, microeconomic as well as nutritional and cultural benefits.

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