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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.
31

Metodologias para determinação da reação de cultivares de soja à Fusarium tucumaniae

Franco, Helena Baroni Junqueira [UNESP] 18 May 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-05-18Bitstream added on 2014-06-13T19:16:32Z : No. of bitstreams: 1 franco_hbj_me_jabo.pdf: 828158 bytes, checksum: 3da61c47398d1434dae4fea307ba8e5b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Objetivou-se estudar diferentes metodologias de inoculação de Fusarium tucumaniae em folhas destacadas e em plântulas de soja, visando à caracterização da reação de resistência de cultivares de soja à F. tucumaniae. O trabalho foi desenvolvido em diferentes etapas relacionadas a seguir: obtenção e manutenção do inóculo; avaliação do desenvolvimento do patógeno em diferentes meios de cultura e diferentes luminosidades; avaliação de diferentes métodos de inoculação em folhas destacadas acondicionadas em papel de filtro e em solo, incubadas em duas temperaturas; avaliação de métodos de inoculação em plântulas cultivadas em casa de vegetação (primavera/verão e outono/inverno), reação de cultivares de soja a F. tucumaniae avaliadas em folhas destacadas, reação de cultivares de soja a F. tucumaniae avaliadas em plântulas (outono/inverno). As análises dos resultados permitiram concluir maior esporulação do fungo em meio de grãos de sorgo. As metodologias de inoculação de plântulas foram bem sucedidas na época de outono/inverno 2005, observando-se infecção das plântulas, principalmente de variedades suscetíveis, e os sintomas típicos da doença ocorreram em todos os métodos utilizados. FT-Cristalina apresentou maior nível de infecção da planta, para o método de grãos de sorgo (GS). O método de inoculação, em folhas destacadas, com grãos de aveia, promoveu maior infecção nas folhas e, o ambiente mais propício ao desenvolvimento dos sintomas da doença foi o solo a 23ºC. A cultivar FT-Estrela apresentou 90,2% de plântulas mortas, e CAC-1 46,9% (método GS). No método da folha destacada não foi possível caracterizar a reação das cultivares estudadas. / Detached leaves and seedlings of some cultivars were inoculated with F. tucumaniae using different methodologies in order to evaluated their resistance reaction. The conduction of the research work consisted of the following phases: obtainment and maintenance the isolate, evaluation of the pathogen growth and sporulation in different cultura media and luminosity; evaluation of different inoculation methods in detached leaves conditioned either in filter paper and soil being, incubated under two temperatures; evaluation of inoculation methods in soybean seedlings developed in greenhouse (Spring/Summer and Autumn/Winter); reaction of soybean cultivars to F. tucumaniae evaluated in detached leaves; reaction of soybean cultivars to F. tucumaniae evaluated in seedling (Autumn/Winter). The obtained results showed that the fungus sporulation was more intense when grown in a sorghum grain medium. Inoculation methodologies in seedlings showed best results when carried out during the 2005 Autumn/Winter period, because seedlings infection was observed, mainly in the susceptible cultivars, and all the employed methods allowed observation of the disease typical symptoms. FT-Cristalina was the cultivar in which the highest level of plant infection was observed, when the sorghum grain method (GS) was employed. The oat grain inoculation method in detached leaves, led to the highest leaf infection index, and the environmental condition which allowed the highest degree of leaf infection was in the soil under 23oC. FT-Estrela cultivar had 90.2% of their seedlings dead whereas for the CAC-1 cultivar that value was of 46.9% (method GS). Cultivars reaction could not be evaluated by means of the detached leaf method.
32

Metodologias para determinação da reação de cultivares de soja à Fusarium tucumaniae /

Franco, Helena Baroni Junqueira. January 2007 (has links)
Orientador: Maria Aparecida Pessoa da Cruz Centurion / Banca: Vanoli Fronza / Banca: Antonio Orlando Di Mauro / Resumo: Objetivou-se estudar diferentes metodologias de inoculação de Fusarium tucumaniae em folhas destacadas e em plântulas de soja, visando à caracterização da reação de resistência de cultivares de soja à F. tucumaniae. O trabalho foi desenvolvido em diferentes etapas relacionadas a seguir: obtenção e manutenção do inóculo; avaliação do desenvolvimento do patógeno em diferentes meios de cultura e diferentes luminosidades; avaliação de diferentes métodos de inoculação em folhas destacadas acondicionadas em papel de filtro e em solo, incubadas em duas temperaturas; avaliação de métodos de inoculação em plântulas cultivadas em casa de vegetação (primavera/verão e outono/inverno), reação de cultivares de soja a F. tucumaniae avaliadas em folhas destacadas, reação de cultivares de soja a F. tucumaniae avaliadas em plântulas (outono/inverno). As análises dos resultados permitiram concluir maior esporulação do fungo em meio de grãos de sorgo. As metodologias de inoculação de plântulas foram bem sucedidas na época de outono/inverno 2005, observando-se infecção das plântulas, principalmente de variedades suscetíveis, e os sintomas típicos da doença ocorreram em todos os métodos utilizados. FT-Cristalina apresentou maior nível de infecção da planta, para o método de grãos de sorgo (GS). O método de inoculação, em folhas destacadas, com grãos de aveia, promoveu maior infecção nas folhas e, o ambiente mais propício ao desenvolvimento dos sintomas da doença foi o solo a 23ºC. A cultivar FT-Estrela apresentou 90,2% de plântulas mortas, e CAC-1 46,9% (método GS). No método da folha destacada não foi possível caracterizar a reação das cultivares estudadas. / Abstract: Detached leaves and seedlings of some cultivars were inoculated with F. tucumaniae using different methodologies in order to evaluated their resistance reaction. The conduction of the research work consisted of the following phases: obtainment and maintenance the isolate, evaluation of the pathogen growth and sporulation in different cultura media and luminosity; evaluation of different inoculation methods in detached leaves conditioned either in filter paper and soil being, incubated under two temperatures; evaluation of inoculation methods in soybean seedlings developed in greenhouse (Spring/Summer and Autumn/Winter); reaction of soybean cultivars to F. tucumaniae evaluated in detached leaves; reaction of soybean cultivars to F. tucumaniae evaluated in seedling (Autumn/Winter). The obtained results showed that the fungus sporulation was more intense when grown in a sorghum grain medium. Inoculation methodologies in seedlings showed best results when carried out during the 2005 Autumn/Winter period, because seedlings infection was observed, mainly in the susceptible cultivars, and all the employed methods allowed observation of the disease typical symptoms. FT-Cristalina was the cultivar in which the highest level of plant infection was observed, when the sorghum grain method (GS) was employed. The oat grain inoculation method in detached leaves, led to the highest leaf infection index, and the environmental condition which allowed the highest degree of leaf infection was in the soil under 23oC. FT-Estrela cultivar had 90.2% of their seedlings dead whereas for the CAC-1 cultivar that value was of 46.9% (method GS). Cultivars reaction could not be evaluated by means of the detached leaf method. / Mestre
33

Estratégias de seleção de genótipos de soja para resistência à podridão vermelha das raízes / Selection strategies of soybean genotypes resistant to sudden death syndrome

Walter Fernando Bernardi 01 September 2008 (has links)
Nas últimas décadas, a podridão vermelha das raízes da soja (PVR), causada pelo Fusarium solani f.sp. glycines (FSG), tornou-se uma doença séria nas regiões brasileiras onde já foi constatada, sendo a utilização de cultivares resistentes um componente fundamental de um sistema integrado de controle. Este trabalho teve por objetivo pesquisar estratégias de seleção de genótipos resistentes a PVR. Várias metodologias foram implementadas: avanço de progênies até a geração F7:2 e seleção em campo infestado, de progênies selecionadas em F2. Avaliou-se o cruzamento IAC 4 x Conquista em casa de vegetação (geração F3:2) e em campo infestado (gerações F3:2, F4:2 e F5:2), através de estudo de estabilidade e adaptabilidade das progênies. As metodologias de infecção em vasos de barro e bandejas de isopor em casa de vegetação foram comparadas para melhorar a eficiência de seleção; também foi feita análise de repetibilidade dos sintomas foliares da PVR, para otimização do número de avaliações necessárias para classificar o genótipo de soja quanto à reação ao FSG. Cultivares brasileiras de soja foram avaliadas em campo infestado. Em campo, as plantas foram avaliadas no estádio R5-6, com notas variando de 1 (ausência de sintomas) a 5 (100% da raiz principal com sintomas). Em casa de vegetação, as plantas foram avaliadas aos 35 dias pós-semeadura para sintomas radiculares e da parte aérea. Houve eficiência da seleção para resistência a PVR tanto em F2 (sintomas foliares em casa de vegetação) quanto em F7:2 (sintomas radiculares em campo naturalmente infestado). A seleção praticada nas gerações intermediárias também foi eficiente para aumentar a produtividade de grãos das progênies. Para o cruzamento IAC 4 x Conquista nas gerações F3:2, F4:2 e F5:2 em campo naturalmente infestado e na F3:2 em casa de vegetação, a metodologia de Annicchiarico possibilitou a seleção de genótipos com maior estabilidade e adaptabilidade para os diferentes ambientes; com o estudo genético destas gerações, demonstrou que há efeitos gênicos aditivos e dominantes no controle genético da PVR. Além disso, constatou-se que os genes responsáveis pela resistência estão dispersos nos genitores, provavelmente agrupados em blocos gênicos. A presença de dominância indica que a seleção deve ser postergada para gerações com maior homozigose (linhagem pura); esta idéia foi reforçada pela baixa herdabilidade ao nível de plantas. O uso de bandejas de isopor foi significativamente mais eficiente do que vasos de barro para inoculação de FSG em casa de vegetação. Pela análise de repetibilidade, detectou-se que quatro avaliações foram suficientes para discriminar se o genótipo era realmente suscetível ao FSG. A correlação da geração F3:2 (IAC 4 x Conquista) entre campo infestado e casa de vegetação foi praticamente nula; no entanto, 54% das progênies selecionadas em campo também foram selecionadas em casa de vegetação. A seleção de genótipos superiores para resistência ao FSG não é tarefa fácil, mas pode ser aprimorada pelo uso conjugado de metodologias suplementares que aumentem a eficiência de seleção. / During the last decades, soybean sudden death syndrome (SDS), caused by Fusarium solani f.sp. glycines (FSG), has become a serious disease in the regions where it was encountered. The use of resistant soybean cultivars has been an important component of an integrated management system. The aim of this work was to research selection strategies of SDS-resistant genotypes. A number of methodologies were used: self pollination up to generation F7:2 and progeny selection in infested field of selected F2. The crossing IAC 4 x Conquista was studied in greenhouse (generation F3:2) and in a naturally infested field (generations F3:2, F4:2 and F5:2), where the progeny stability and adaptability study was carried out. The methodologies of infection in clay pots and polystyrene trays in greenhouse were compared to improve selection efficiency. An analysis of the repeatability of foliar SDS symptoms was also performed in order to optimize the number of evaluations needed to classify a soybean genotypes reaction to FSG. Brazilian soybean cultivars were evaluated in a naturally infested field, where plants were evaluated at stage R5-6 with scores varying from 1 (absence of symptoms) to 5 (main root 100% symptoms). In the greenhouse, the plants were evaluated 35 days after sowing for root symptoms, while the leaf symptoms was only evaluated after the appearance of symptoms. The selection done in F2 (leaf symptoms in greenhouse) as well as F7:2 (root symptoms in infested field) for FSG were efficient. The selections performed in intermediary generations were efficient in increasing the grain yield of the progeny. Studies of the F3:2, F4:2 and F5:2 generations of the IAC 4 x Conquista cross in an infested field and F3:2 in greenhouse, enabled through Annicchiaricos methodology, the selection of genotypes with greater stability and adaptability to different environments. The genetic study of these generations demonstrated there are additive and dominant genetic effects on the genetic control of SDS. Moreover, it was noted that the genes responsible for resistance are dispersed on the genitors, probably grouped into genic blocks. The presence of dominance indicates that the selection should be passed onto generations with greater homozygosity. There is also a clear indication that breeders should work with progeny lines in order to assist selection due to the low inheritability at the individual plant level. For the experiments with different FSG inoculation methodologies (clay pots and polystyrene trays) in greenhouse the use of trays was significantly more efficient; by studying the repeatability analysis, it was found that four evaluations is enough to discriminate if the genotype is really susceptible to FSG. The correlation of the F3:2 generation (IAC 4 x Conquista) between infested field and greenhouse was practically null; however, 54% of the progeny selected in the field were selected in greenhouse. As observed, the selection of superior genotypes for FSG resistance is not an easy task, but may be improved by means of new methodologies and the conjugated use of methodologies which improve selection efficiency.
34

Estudo químico de fungos da rizosfera de Senna spectabilis utilizando abordagem OSMAC e ferramentas analíticas do estado da arte para anotação e caracterização de metabólitos /

Vieira, Natália Carolina. January 2020 (has links)
Orientador: Ian Castro-Gamboa / Resumo: A utilização de produtos naturais pela humanidade, como agentes terapêuticos, é descrita desde primórdios da antiguidade e representam um importante aliado no tratamento de doenças. Com isso a busca por novas ferramentas analíticas mais robustas, com abordagem metabolômica se faz necessária, de forma a otimizar e acelerar a busca por novas moléculas e substâncias com atividade biológica promissora. Nesse contexto, esse trabalho tem como alvo de estudo, os fungos Fusarium solani e Purpureocillium lilacinum isolados da rizosfera de Senna spectabilis. Essas espécies de microrganismos apresentam muitos estudos químicos relatados na literatura, o que influenciou o interesse em realizar os estudos de OSMAC (One Strain Many Compounds). Para, assim, verificar a variação metabólica que acontece com esses fungos em diferentes tipos de cultivo (variando meio de cultura e agitação) incluindo o co-cultivo. Para os extratos obtidos também foram realizados os ensaios biológicos citotóxico e antibacteriano. Foram utilizadas ferramentas analíticas do estado da arte como GC-MS (Cromatografia Gasosa acoplada a Espectrometria de Massas) e LC-MS (Cromatografia Líquida acoplada a Espectrometria de Massas) fazendo uso das ferramentas de bioinformática Molecular Networking (ou Rede Molecular) com a plataforma GNPS (Global Natural Product Social Molecular Networking) e o UNIFI (Sistema de informação científica – Waters Corporation). A espectrometria de massas (MS) foi uma grande aliada que ajudou a d... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The use of natural products by mankind, as therapeutic agents, has been described since ancient times and represents an important ally in the treatment of diseases. Thus, the search for new more robust analytical tools, with a metabolomic approach is necessary, in order to optimize and accelerate the search for new molecules and substances with promising biological activity. In this context, this study is aimed at studying Fusarium solani and Purpureocillium lilacinum fungi isolated from the rhizosphere of Senna spectabilis. These species of microorganisms have many chemical studies reported in the literature, which influenced the interest in carrying out the studies of OSMAC (One Strain Many Compounds). Thus, to verify the metabolic variation that happens with these fungi in different types of cultivation (varying culture medium and agitation) including co-culture. For the extracts obtained, cytotoxic and antibacterial biological tests were also performed. State-of-the-art analytical tools such as GCMS (Gas Chromatography coupled to Mass Spectrometry) and LC-MS (Liquid Chromatography coupled to Mass Spectrometry) were used alongside the bioinformatics tools Molecular Networking with the platform GNPS (Global Natural Product Social Molecular Networking) and UNIFI (Scientific Information System - Waters Corporation). Mass spectrometry (MS) was a great ally that helped to demonstrate the variation of the metabolites profile of these microorganisms in different cultures, in whic... (Complete abstract click electronic access below) / Doutor
35

Relações genéticas entre produtividade de óleo e podridão vermelha das raízes em soja / Genetic relations between oil yield and sudden death syndrome (SDS) in soybean

Oliveira, Inocencio Junior de 19 May 2011 (has links)
A demanda por óleos vegetais tem sido crescente, principalmente para utilização como fonte de energia renovável na forma de biodiesel. Somando-se a isso, a podridão vermelha das raízes da soja (PVR), ou síndrome da morte súbita, causada pelo fungo Fusarium solani f.sp. glycines, tornou-se uma doença preocupante para os sojicultores, técnicos e pesquisadores, sendo uma estratégia recomendada a adoção de um sistema de controle integrado em que a utilização de cultivares tolerantes é um componente indispensável. Assim, este trabalho teve por objetivo verificar a possibilidade de se reunir em uma mesma planta de soja genes para alta produtividade de óleo e para tolerância a PVR. O sistema genético compreendeu um dialelo parcial 7x7, envolvendo sete genitores com alta produtividade de óleo e sete genitores tolerantes a PVR. A maioria dos genitores compreendeu linhagens experimentais desenvolvidas no Setor de Genética Aplicada às Espécies Autógamas (ESALQ/USP). Os experimentos envolveram as plantas F2, na safra 2008/2009 e progênies F2:3, na safra 2009/2010, para avaliação de caracteres agronômicos, do teor de óleo e produtividade de óleo em campo experimental; já a avaliação da reação a PVR foi realizada em progênies F2:4, em casa de vegetação com inoculação artificial do patógeno, por meio de uma escala de notas para a severidade dos sintomas radiculares. Além disso, por meio de marcadores microssatélites fez-se um estudo de genética de associação entre os marcadores e os caracteres reação a PVR e teor de óleo em três populações. Os resultados evidenciaram a existência de variabilidade nos genitores e nas progênies para todos os caracteres avaliados. O genitor com a maior capacidade geral de combinação e média de teor de óleo foi a cultivar A 7002; por outro lado, os menores valores foram verificados em PI 520733 e IAC 100. Os cruzamentos mais produtivos em óleo foram aqueles que envolveram o genitor A 7002, exceto quando este foi cruzado com IAC 100. Dez cruzamentos (USP 70004 com USP 14-10-38, USP 14-01-20, USP 14-13-16 e M-Soy 8001; USP 14-10-38 com USP 70057 e USP 70080; M-Soy 8001 com USP 70006, USP 70080 e USP 70123; e USP 14-01-20 x USP 70006) destacaram-se por originar a maioria de suas progênies com as melhores características em todos os caracteres, ou seja, apresentaram ciclo precoce ou semi-precoce, altura média, plantas eretas e com valor agronômico bom ou médio, alta produtividade de grãos e de óleo, alto teor de óleo e tolerância a PVR. Nenhum cruzamento originou a maioria de suas progênies com as piores características em todos os caracteres. Teor de óleo apresentou baixa correlação genética com altura da planta na maturidade, acamamento, valor agronômico, produtividade de grãos e reação a PVR. PVR apresentou baixa correlação genética com acamamento, produtividade de grãos, teor de óleo, produtividade de óleo; entretanto, foi possível obter progênies com alta produtividade de grãos e de óleo e tolerantes a PVR. Os marcadores microssatélites mostraram-se polimórficos e, foram associados dois locos SSR ao caráter teor de óleo e outros dois locos ao caráter reação a PVR. / The demand for vegetable oils has increased, mainly because of its use as a renewable energy source like biodiesel. Moreover, the sudden death syndrome (SDS) in soybean, caused by the fungus Fusarium solani f.sp. glycines, has become a worrying disease for soybean producers, technicians and researchers, and the adoption of an integrated control system using tolerant cultivars as an essential component has been a recommended strategy. This work aimed to verify the possibility of gathering genes for high oil yield and tolerance to SDS in the same soybean plant. The genetic system comprised a partial diallel 7x7 involving seven parents with high oil yield and seven parents tolerant to SDS. Most of the parents were experimental lines developed at the Sector of Genetics Applied to Self-Pollinated Species (ESALQ/USP). The 2008/2009 trials involved the F2 plants, and the 2009/2010 trials involved the evaluation of F2:3 progenies traits, such as agronomic characters, oil content and oil yield in the experimental field; whereas the analysis of the SDS reaction was tested in F2:4 progenies, in a greenhouse with artificial inoculation of the pathogen through a rating scale for severity of radicular symptoms. Moreover, a study of genetic association among microsatellite markers and the characters reaction to SDS and oil content in three populations was performed. The results showed the existence of variability in parents and progenies for all characters. The parent who had the highest general combining ability and average oil content was the cultivar A 7002; on the other hand, the lowest values were found in PI 520733 and IAC 100. The crosses that originated the best oil content progenies have involved the parent A 7002, except when it was crossed with IAC 100. Ten crosses (USP 70004 with USP 14-10-38, USP 14-01-20, USP 14-13-16 and M-Soy 8001; USP 14-10-38 with USP 70057 and USP 70080; M-Soy 8001 with USP 70006, USP 70080 and USP 70123; USP 14-01-20 x USP 70006) distinguished from the others by originating the majority of their progenies with the best features in all traits, in other words, showed early and semi-early maturity, medium height, upright plants, good or average agronomic value, high grain and oil yield, high oil content and tolerance to SDS. None of the crosses originated the majority of their progeny with the worst characteristics in all traits. Oil content showed low genetic correlation with plant height at maturity, lodging, agronomic value, yield and reaction to SDS. SDS showed a low genetic correlation with lodging, grain yield, oil content, oil yield. However, it was possible to obtain progenies with high grain and oil yield and tolerance to SDS. The microsatellite markers were polymorphic and, moreover, two SSR loci were associated with the character oil content and other two loci to the character SDS reaction.
36

Relações genéticas entre produtividade de óleo e podridão vermelha das raízes em soja / Genetic relations between oil yield and sudden death syndrome (SDS) in soybean

Inocencio Junior de Oliveira 19 May 2011 (has links)
A demanda por óleos vegetais tem sido crescente, principalmente para utilização como fonte de energia renovável na forma de biodiesel. Somando-se a isso, a podridão vermelha das raízes da soja (PVR), ou síndrome da morte súbita, causada pelo fungo Fusarium solani f.sp. glycines, tornou-se uma doença preocupante para os sojicultores, técnicos e pesquisadores, sendo uma estratégia recomendada a adoção de um sistema de controle integrado em que a utilização de cultivares tolerantes é um componente indispensável. Assim, este trabalho teve por objetivo verificar a possibilidade de se reunir em uma mesma planta de soja genes para alta produtividade de óleo e para tolerância a PVR. O sistema genético compreendeu um dialelo parcial 7x7, envolvendo sete genitores com alta produtividade de óleo e sete genitores tolerantes a PVR. A maioria dos genitores compreendeu linhagens experimentais desenvolvidas no Setor de Genética Aplicada às Espécies Autógamas (ESALQ/USP). Os experimentos envolveram as plantas F2, na safra 2008/2009 e progênies F2:3, na safra 2009/2010, para avaliação de caracteres agronômicos, do teor de óleo e produtividade de óleo em campo experimental; já a avaliação da reação a PVR foi realizada em progênies F2:4, em casa de vegetação com inoculação artificial do patógeno, por meio de uma escala de notas para a severidade dos sintomas radiculares. Além disso, por meio de marcadores microssatélites fez-se um estudo de genética de associação entre os marcadores e os caracteres reação a PVR e teor de óleo em três populações. Os resultados evidenciaram a existência de variabilidade nos genitores e nas progênies para todos os caracteres avaliados. O genitor com a maior capacidade geral de combinação e média de teor de óleo foi a cultivar A 7002; por outro lado, os menores valores foram verificados em PI 520733 e IAC 100. Os cruzamentos mais produtivos em óleo foram aqueles que envolveram o genitor A 7002, exceto quando este foi cruzado com IAC 100. Dez cruzamentos (USP 70004 com USP 14-10-38, USP 14-01-20, USP 14-13-16 e M-Soy 8001; USP 14-10-38 com USP 70057 e USP 70080; M-Soy 8001 com USP 70006, USP 70080 e USP 70123; e USP 14-01-20 x USP 70006) destacaram-se por originar a maioria de suas progênies com as melhores características em todos os caracteres, ou seja, apresentaram ciclo precoce ou semi-precoce, altura média, plantas eretas e com valor agronômico bom ou médio, alta produtividade de grãos e de óleo, alto teor de óleo e tolerância a PVR. Nenhum cruzamento originou a maioria de suas progênies com as piores características em todos os caracteres. Teor de óleo apresentou baixa correlação genética com altura da planta na maturidade, acamamento, valor agronômico, produtividade de grãos e reação a PVR. PVR apresentou baixa correlação genética com acamamento, produtividade de grãos, teor de óleo, produtividade de óleo; entretanto, foi possível obter progênies com alta produtividade de grãos e de óleo e tolerantes a PVR. Os marcadores microssatélites mostraram-se polimórficos e, foram associados dois locos SSR ao caráter teor de óleo e outros dois locos ao caráter reação a PVR. / The demand for vegetable oils has increased, mainly because of its use as a renewable energy source like biodiesel. Moreover, the sudden death syndrome (SDS) in soybean, caused by the fungus Fusarium solani f.sp. glycines, has become a worrying disease for soybean producers, technicians and researchers, and the adoption of an integrated control system using tolerant cultivars as an essential component has been a recommended strategy. This work aimed to verify the possibility of gathering genes for high oil yield and tolerance to SDS in the same soybean plant. The genetic system comprised a partial diallel 7x7 involving seven parents with high oil yield and seven parents tolerant to SDS. Most of the parents were experimental lines developed at the Sector of Genetics Applied to Self-Pollinated Species (ESALQ/USP). The 2008/2009 trials involved the F2 plants, and the 2009/2010 trials involved the evaluation of F2:3 progenies traits, such as agronomic characters, oil content and oil yield in the experimental field; whereas the analysis of the SDS reaction was tested in F2:4 progenies, in a greenhouse with artificial inoculation of the pathogen through a rating scale for severity of radicular symptoms. Moreover, a study of genetic association among microsatellite markers and the characters reaction to SDS and oil content in three populations was performed. The results showed the existence of variability in parents and progenies for all characters. The parent who had the highest general combining ability and average oil content was the cultivar A 7002; on the other hand, the lowest values were found in PI 520733 and IAC 100. The crosses that originated the best oil content progenies have involved the parent A 7002, except when it was crossed with IAC 100. Ten crosses (USP 70004 with USP 14-10-38, USP 14-01-20, USP 14-13-16 and M-Soy 8001; USP 14-10-38 with USP 70057 and USP 70080; M-Soy 8001 with USP 70006, USP 70080 and USP 70123; USP 14-01-20 x USP 70006) distinguished from the others by originating the majority of their progenies with the best features in all traits, in other words, showed early and semi-early maturity, medium height, upright plants, good or average agronomic value, high grain and oil yield, high oil content and tolerance to SDS. None of the crosses originated the majority of their progeny with the worst characteristics in all traits. Oil content showed low genetic correlation with plant height at maturity, lodging, agronomic value, yield and reaction to SDS. SDS showed a low genetic correlation with lodging, grain yield, oil content, oil yield. However, it was possible to obtain progenies with high grain and oil yield and tolerance to SDS. The microsatellite markers were polymorphic and, moreover, two SSR loci were associated with the character oil content and other two loci to the character SDS reaction.
37

Mapping QTL for root rot resistance, root traits, and morphological trait in a common bean recombinant inbred population

Hagerty, Christina H. 13 March 2013 (has links)
Root rot diseases of bean (Phaseolus vulgaris L.) are a problem wherever they are grown, and are a major constraint to dry edible and snap bean production. Root rot is a primary yield limitation of snap bean production in the US, especially within the top three snap bean producing states of Wisconsin, Oregon and New York. Bean root rot pathogens will be present by the end of the first season even when starting with clean ground. The decline in yield can be relatively slow, so growers might not notice or appreciate the hidden yield cost associated with root rot disease. Traditional methods for disease control such as fungicides, crop rotations, cover crops, seedbed preparations have been proven ineffective (either physically ineffective or economically unviable) against root rot. Therefore, genetic resistance is needed. In order to address the need for genetic resistance to root rot in snap beans, the highly root rot resistant line RR6950, a small seeded black indeterminate type IIIA accession of unknown origin, was crossed with OSU5446, a highly root rot susceptible determinate type I blue lake four-sieve breeding line to produce the RR138 recombinant inbred mapping population. In this study we evaluated the RR138 RI population in the F₆ generation for resistance to Fusarium solani root rot in Oregon and Aphanomyces euteiches root rot in Wisconsin. We also evaluated this population for morphological traits and root structural traits including pod height, pod width, pod length, pod wall thickness, strings, seed color, flower color, tap and basal root diameter, and root angle measurements. The RR138 population was also genotyped on the 10K BeanCAP Illumina Beadchip. The Single Nucleotide Polymorphism (SNP) data was used to assemble a high-density linkage map and Quantitative Trait Loci (QTL) for phenotypic data were evaluated. The linkage map produced from this study contained 1,689 SNPs across 1,196cM. The map was populated with 1 SNP for every 1.4cM, spanning across 11 linkage groups. Three QTL associated with A. euteiches root rot resistance were consistently expressed in 2011 and 2012 trials. A. euteiches QTL were found on Pv02, Pv04, and Pv06 and accounted for 7-17% of total genetic variation. Two QTL associated with F. solani were found in 2011 trial on Pv03 and Pv07, account for 9 and 22% of total genetic variation, respectively. We also found several QTL for morphological traits and root structural traits including QTL for pod fiber and pod height on Pv04, pod length on Pv01, strings on Pv01, taproot diameter on Pv05, and shallow basal root angle on Pv05, accounting for 21, 26, 12, 20, 11, and 19% of total genetic variation, respectively. QTL discovered from Oregon data for F. solani resistance did not cluster with QTL for A. euteiches root rot resistance. "SNP0928_7", was highly associated with F. solani resistance on Pv07 and "SNP0508_2", was highly associated with A. euteiches on Pv02. QTL and markers associated with QTL from this study will be of value to snap bean breeders developing root rot resistant lines with processing traits, and provide more information about targeting the mechanism of resistance. / Graduation date: 2013
38

Improving resistance to Fusarium root rot [Fusarium solani (Mart.) Sacc. f. sp. phaseoli (Burkholder) W.C. Snyder & H.N. Hans] in common bean (Phaseolus vulgaris L.)

Mugisha, Clare Mukankusi. January 2008 (has links)
Fusarium root rot (FRR) disease, caused by the fungus Fusarium solani f. sp. phaseoli (FSP), is an important soil-borne disease reducing common bean (Phaseolus vulgaris L.) yields, and hence food security, in Uganda and elsewhere in developing countries where the crop is grown without fungicides. The key aim of this study was to elucidate the significance of bean root rot (BRR), appraise methods for screening germplasm for resistance to FRR, determine the genotypic variability of resistance, and the inheritance of resistance to FRR in common bean. This information was deemed useful in devising an appropriate strategy for breeding FRR resistance in beans. A participatory rural appraisal (PRA) was conducted in south-western and eastern Uganda to ascertain farmers’ awareness of BRR and their influence on preferred bean varieties. Bean root rot is considered to be the most devastating and most recognised disease, especially in south-western Uganda. Control measures for BRR were very minimal, and in some cases, non-existent. Use of resistant varieties to control the disease was not evident, because the most popular varieties were susceptible to the disease. The resistant bean varieties currently available have undesirable characteristics such as small seed size, black seed and late maturity. Large-seeded bean varieties, even though cited as being more susceptible to BRR than the small-seeded varieties, are still very popular. The study highlighted the need for breeding FRR resistance in the large-seeded bean varieties that are highly preferred by farmers. Four isolates of FSP (FSP-1, FSP-2, FSP-3 and FSP-4) were tested for pathogenicity under screenhouse and laboratory conditions. In addition, three methods of storing and maintaining the viability of FSP isolates were appraised. The isolate FSP-3, was found to be the most pathogenic, resulting in 100% disease incidence on all bean varieties tested, with high severity scores. The potato dextrose agar (PDA) slants stored at 5oC were found to be the best method of storage for pathogenic isolates. The FSP-3 isolate was subsequently utilised for screening bean lines for resistance to FRR. The influence of soil composition, irrigation frequency, and inoculation technique on the severity of FRR was studied on six bean lines. Interactions of irrigation frequency, soil composition, and bean lines were not significant. The 50% swamp soil:50% forest soil composition and forest soil alone categorized the varieties most distinctly according to their reaction to FRR. Also, the best distinct classification for the varieties was obtained under treatments that were watered daily and once in a week. Based on economic considerations, the standard forest soil and daily irrigation were subsequently adopted for screening bean germplasm for resistance to FRR. It was also found that sorghum seed as a medium for pathogen inoculation was better than the agar slurry medium. One hundred and forty seven common bean varieties were evaluated for resistance to FRR (isolate FSP-3) under screenhouse conditions. In order to confirm this resistance, 46 common bean lines selected from the screenhouse trial were further evaluated using natural inoculum in a BRR-infested field. Forty-four varieties comprising ten large-seeded, four medium-seeded and 30 small-seeded varieties showed moderate resistance to FRR; but none were resistant or immune to the disease. Based on adaptability, eight moderately resistant varieties were selected for use as parents in the study of inheritance of resistance to FRR. A 12 x 12 diallel mating design was utilised to develop 66 F1 and F2 populations, plus their reciprocal crosses, with the aim of studying the mode of inheritance of resistance to FRR. The F1 and F2 progeny evaluations showed that FRR resistance was mainly governed by additive genes in most populations. However, there were a few crosses which displayed highly significant specific combining ability (SCA) effects, implying that dominant effects were important in some populations. Maternal effects were also highly significant at both the F1 and F2 generations, suggesting that resistance was modified by cytoplasmic genes. The non-maternal effects were also significant in some populations, suggesting that the cytoplasmic genes were interacting with nuclear genes. The number of genes governing resistance to FRR varied from two to nine among the eight sources of resistance. The allelism test of resistant x resistant populations, and the observation of continuous distributions of severity scores, suggested the presence of many loci governing FRR resistance in beans. Broad sense heritability of disease resistance varied from 0.22-0.69, while heritability in the narrow sense was estimated as 0.35-0.49 in the populations. These results suggested that selection and backcrossing to both parents would be the best breeding procedures for improving resistance in the popular large-seeded bean varieties in Uganda. However, there could be complications in breeding for resistance to FRR in beans, because resistance was modified by cytoplasmic gene effects and their interaction with nuclear genes in some of the populations. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.

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