Does the I86F mutation of succinate dehydrogenase subunit c increase fungicide resistance and have a fitness in Asian Soybean Rust (Phakopsora pachyrhizi)?

Detalhes bibliográficos
Autor(a) principal: Borba, Jackeline Pedriana
Data de Publicação: 2020
Tipo de documento: Dissertação
Idioma: eng
Título da fonte: Biblioteca Digital de Teses e Dissertações da USP
Texto Completo: http://www.teses.usp.br/teses/disponiveis/11/11137/tde-06032020-112224/
Resumo: Asian Soybean Rust (ASR) is the most economically important soybean disease worldwide, and can cause yield losses of up to 80%. Brazil is the second largest producer and the most important soybean exporter (CONAB, 2018), therefore any constraints to soybean production have a negative impact on the national economy. ASR management relies mainly in fungicide application, but lower sensitivity for all the current mode of action fungicides has been reported. Of twenty active ingredients that comprise the SDHI fungicides, only three of these are labeled for soybean rust disease control. The limited availability of chemical groups for ASR disease control and the resourcing time to discovery, development and registration of new fungicides makes the fungicide resistance management critical for soybean crop production. Genetic structure is of importance to understand and predict the potential for pathogen populations to evolve and adapt in agricultural ecosystems. Three contrasting strains for SDHI sensitivity - 100% I86 susceptible (S); 50% I86/50% 86F resistant (R); 100% 86F resistant - were obtained by selecting survival uredinia at high carboxamide doses. The level of resistance was determined by EC50 in detached leaf assay. Higher I86F frequencies were associated with higher SDHI concentrations. Benzovindiflupyr and Fluxapyroxad are cross resistant between each other, but EC50 values for mutants strains increased less for Fluxaproxad than for Benzovindiflupyr. Mutant strains showed a faster initial development compared with the wild- type strain, with faster germination and appressorium development, increasing the chance of successful infection. Shorter latent period and higher disease severity was observed for the heterokaryotic (H) strain when compared with both 86F (R) and I86 (S) strains. Despite the faster initial development and virulence, resistant (R) strains showed a competitive disadvantageous when mixed with the wild type (S) strains. A decrease in 86F frequency was observed during five disease cycles. The frequency of 86F allele is stable in pure culture over five disease cycles in non-treated soybean leaves.
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spelling Does the I86F mutation of succinate dehydrogenase subunit c increase fungicide resistance and have a fitness in Asian Soybean Rust (Phakopsora pachyrhizi)?A mutação I86F na subunidade c da enzima succinato desidrogenase aumenta a resistência à fungicidas e tem um custo adaptativo na Ferrugem Asiática da Soja (Phakopsora pachyrhizi)?Asian soybean rustCusto adaptativoFerrugem asiática da sojaFitness costFungicide resistance managementManejo de resistência à fungicidasSDHI fungicidasSDHI fungicidesAsian Soybean Rust (ASR) is the most economically important soybean disease worldwide, and can cause yield losses of up to 80%. Brazil is the second largest producer and the most important soybean exporter (CONAB, 2018), therefore any constraints to soybean production have a negative impact on the national economy. ASR management relies mainly in fungicide application, but lower sensitivity for all the current mode of action fungicides has been reported. Of twenty active ingredients that comprise the SDHI fungicides, only three of these are labeled for soybean rust disease control. The limited availability of chemical groups for ASR disease control and the resourcing time to discovery, development and registration of new fungicides makes the fungicide resistance management critical for soybean crop production. Genetic structure is of importance to understand and predict the potential for pathogen populations to evolve and adapt in agricultural ecosystems. Three contrasting strains for SDHI sensitivity - 100% I86 susceptible (S); 50% I86/50% 86F resistant (R); 100% 86F resistant - were obtained by selecting survival uredinia at high carboxamide doses. The level of resistance was determined by EC50 in detached leaf assay. Higher I86F frequencies were associated with higher SDHI concentrations. Benzovindiflupyr and Fluxapyroxad are cross resistant between each other, but EC50 values for mutants strains increased less for Fluxaproxad than for Benzovindiflupyr. Mutant strains showed a faster initial development compared with the wild- type strain, with faster germination and appressorium development, increasing the chance of successful infection. Shorter latent period and higher disease severity was observed for the heterokaryotic (H) strain when compared with both 86F (R) and I86 (S) strains. Despite the faster initial development and virulence, resistant (R) strains showed a competitive disadvantageous when mixed with the wild type (S) strains. A decrease in 86F frequency was observed during five disease cycles. The frequency of 86F allele is stable in pure culture over five disease cycles in non-treated soybean leaves.A Ferrugem Asiática da Soja (ASR) é a doença economicamente mais importante em todo o mundo, e pode causar perdas de rendimento de até 80%. O Brasil é o segundo maior produtor e o maior exportador de soja (CONAB, 2018), portanto, restrições à produção tem um impacto negativo na economia nacional. O manejo da doença depende principalmente da aplicação de fungicidas, entretanto, redução de sensibilidade para todos os fungicidas já foi reportada. Dentre os vinte ingredientes ativos que compõem os fungicidas inibidores da succinato desidrogenase (SDHI) listados no Comitê de Ação de Resistência a Fungicidas (FRAC), apenas três deles são rotulados para o controle da doença da ferrugem da soja. A disponibilidade de poucos grupos químicos para o controle da doença e o tempo para descoberta, desenvolvimento e registro de novos fungicidas tornam o manejo da resistência a fungicida crítico para a produção de soja. A estrutura genética populacional é importante para entender e prever o potencial de populações de patógenos para evoluir e se adaptar em ecossistemas agrícolas. Três isolados contrastantes para sensibilidade à SDHI - 100% I86 Selvagem (S); 50% I86/50% 86F Heterocariótico (H); 100% 86F Resistente (R) - foram obtidos a partir do isolamento de monolesões que sobreviveram a altas doses de carboxamida. O nível de resistência foi determinado por DL50 em ensaio de folhas destacadas. Frequências mais altas de mutações I86F foram associadas à resistência a maiores concentrações de fungicida. Benzovindiflupir e Fluxapiroxade apresentaram resistência cruzada entre si, mas os valores de DL50 para os isolados mutantes aumentaram menos para Fluxapiroxade do que para Benzovindiflupir. Os isolados mutantes apresentaram um desenvolvimento inicial mais rápido em comparação com o isolado sensível, com germinação e desenvolvimento de apressório mais rápidos, aumentando a chance de sucesso na infecção. Período mais curto de latênca e maior severidade foram observados para o isolado heterocariótico (H) em comparação com os isolados 86F (R) e selvagem (S). O custo adaptativo comparativo dos mutantes foi medido misturando os isolados resistentes e sensíveis e medindo a flutuação na frequência de 86F durante cinco ciclos de doença. Apesar do desenvolvimento inicial mais rápido e maior virulência, o isolado resistente (R) mostrou uma desvantagem competitiva quando foi misturado ao isolado selvagem (S) e uma redução na frequência do alelo 86F foi observada. A frequência do alelo 86F parece estável durante cinco ciclos consecutivos da doença quando cultivado sozinho em folhas de soja não tratadas com fungicida.Biblioteca Digitais de Teses e Dissertações da USPVitorello, Claudia Barros MonteiroBorba, Jackeline Pedriana2020-01-22info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfhttp://www.teses.usp.br/teses/disponiveis/11/11137/tde-06032020-112224/reponame:Biblioteca Digital de Teses e Dissertações da USPinstname:Universidade de São Paulo (USP)instacron:USPLiberar o conteúdo para acesso público.info:eu-repo/semantics/openAccesseng2020-03-09T23:42:01Zoai:teses.usp.br:tde-06032020-112224Biblioteca Digital de Teses e Dissertaçõeshttp://www.teses.usp.br/PUBhttp://www.teses.usp.br/cgi-bin/mtd2br.plvirginia@if.usp.br|| atendimento@aguia.usp.br||virginia@if.usp.bropendoar:27212020-03-09T23:42:01Biblioteca Digital de Teses e Dissertações da USP - Universidade de São Paulo (USP)false
dc.title.none.fl_str_mv Does the I86F mutation of succinate dehydrogenase subunit c increase fungicide resistance and have a fitness in Asian Soybean Rust (Phakopsora pachyrhizi)?
A mutação I86F na subunidade c da enzima succinato desidrogenase aumenta a resistência à fungicidas e tem um custo adaptativo na Ferrugem Asiática da Soja (Phakopsora pachyrhizi)?
title Does the I86F mutation of succinate dehydrogenase subunit c increase fungicide resistance and have a fitness in Asian Soybean Rust (Phakopsora pachyrhizi)?
spellingShingle Does the I86F mutation of succinate dehydrogenase subunit c increase fungicide resistance and have a fitness in Asian Soybean Rust (Phakopsora pachyrhizi)?
Borba, Jackeline Pedriana
Asian soybean rust
Custo adaptativo
Ferrugem asiática da soja
Fitness cost
Fungicide resistance management
Manejo de resistência à fungicidas
SDHI fungicidas
SDHI fungicides
title_short Does the I86F mutation of succinate dehydrogenase subunit c increase fungicide resistance and have a fitness in Asian Soybean Rust (Phakopsora pachyrhizi)?
title_full Does the I86F mutation of succinate dehydrogenase subunit c increase fungicide resistance and have a fitness in Asian Soybean Rust (Phakopsora pachyrhizi)?
title_fullStr Does the I86F mutation of succinate dehydrogenase subunit c increase fungicide resistance and have a fitness in Asian Soybean Rust (Phakopsora pachyrhizi)?
title_full_unstemmed Does the I86F mutation of succinate dehydrogenase subunit c increase fungicide resistance and have a fitness in Asian Soybean Rust (Phakopsora pachyrhizi)?
title_sort Does the I86F mutation of succinate dehydrogenase subunit c increase fungicide resistance and have a fitness in Asian Soybean Rust (Phakopsora pachyrhizi)?
author Borba, Jackeline Pedriana
author_facet Borba, Jackeline Pedriana
author_role author
dc.contributor.none.fl_str_mv Vitorello, Claudia Barros Monteiro
dc.contributor.author.fl_str_mv Borba, Jackeline Pedriana
dc.subject.por.fl_str_mv Asian soybean rust
Custo adaptativo
Ferrugem asiática da soja
Fitness cost
Fungicide resistance management
Manejo de resistência à fungicidas
SDHI fungicidas
SDHI fungicides
topic Asian soybean rust
Custo adaptativo
Ferrugem asiática da soja
Fitness cost
Fungicide resistance management
Manejo de resistência à fungicidas
SDHI fungicidas
SDHI fungicides
description Asian Soybean Rust (ASR) is the most economically important soybean disease worldwide, and can cause yield losses of up to 80%. Brazil is the second largest producer and the most important soybean exporter (CONAB, 2018), therefore any constraints to soybean production have a negative impact on the national economy. ASR management relies mainly in fungicide application, but lower sensitivity for all the current mode of action fungicides has been reported. Of twenty active ingredients that comprise the SDHI fungicides, only three of these are labeled for soybean rust disease control. The limited availability of chemical groups for ASR disease control and the resourcing time to discovery, development and registration of new fungicides makes the fungicide resistance management critical for soybean crop production. Genetic structure is of importance to understand and predict the potential for pathogen populations to evolve and adapt in agricultural ecosystems. Three contrasting strains for SDHI sensitivity - 100% I86 susceptible (S); 50% I86/50% 86F resistant (R); 100% 86F resistant - were obtained by selecting survival uredinia at high carboxamide doses. The level of resistance was determined by EC50 in detached leaf assay. Higher I86F frequencies were associated with higher SDHI concentrations. Benzovindiflupyr and Fluxapyroxad are cross resistant between each other, but EC50 values for mutants strains increased less for Fluxaproxad than for Benzovindiflupyr. Mutant strains showed a faster initial development compared with the wild- type strain, with faster germination and appressorium development, increasing the chance of successful infection. Shorter latent period and higher disease severity was observed for the heterokaryotic (H) strain when compared with both 86F (R) and I86 (S) strains. Despite the faster initial development and virulence, resistant (R) strains showed a competitive disadvantageous when mixed with the wild type (S) strains. A decrease in 86F frequency was observed during five disease cycles. The frequency of 86F allele is stable in pure culture over five disease cycles in non-treated soybean leaves.
publishDate 2020
dc.date.none.fl_str_mv 2020-01-22
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/masterThesis
format masterThesis
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dc.identifier.uri.fl_str_mv http://www.teses.usp.br/teses/disponiveis/11/11137/tde-06032020-112224/
url http://www.teses.usp.br/teses/disponiveis/11/11137/tde-06032020-112224/
dc.language.iso.fl_str_mv eng
language eng
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dc.rights.driver.fl_str_mv Liberar o conteúdo para acesso público.
info:eu-repo/semantics/openAccess
rights_invalid_str_mv Liberar o conteúdo para acesso público.
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
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dc.publisher.none.fl_str_mv Biblioteca Digitais de Teses e Dissertações da USP
publisher.none.fl_str_mv Biblioteca Digitais de Teses e Dissertações da USP
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reponame:Biblioteca Digital de Teses e Dissertações da USP
instname:Universidade de São Paulo (USP)
instacron:USP
instname_str Universidade de São Paulo (USP)
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institution USP
reponame_str Biblioteca Digital de Teses e Dissertações da USP
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repository.name.fl_str_mv Biblioteca Digital de Teses e Dissertações da USP - Universidade de São Paulo (USP)
repository.mail.fl_str_mv virginia@if.usp.br|| atendimento@aguia.usp.br||virginia@if.usp.br
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