Stenocarpella spp. inoculum quantification in tropical maize stubble

Detalhes bibliográficos
Autor(a) principal: Pinto, Felipe Augusto Moretti Ferreira
Data de Publicação: 2016
Tipo de documento: Tese
Idioma: eng
Título da fonte: Repositório Institucional da UFLA
Texto Completo: http://repositorio.ufla.br/jspui/handle/1/11558
Resumo: Stenocarpella species (S.maydis and S.macrospora) overwinters in maize stubble and no-till monoculture maize is related to ear and stalk rot outbreaks, but little is known about the factors that contribute to its survival. Therefore this work aimed at determining the contribution of soybean crop rotation and fallow land on pathogen survival and dynamics of maize stubble breakdown, and determining factors that contribute to the pathogens survival. Inn the first article maize fields with history of severe white ear rot were used to determine the stubble sampling size to analyze the pathogen sporulation and viability, as well the maize decomposition. The maize monoculture was compared to one round of soybean rotation and fallow. In the second article, maize fields were selected in the maize growing areas in the state of Minas Gerais for sampling maize stubbles. During the offseason, maize stalks, grains, cobs, fallen maize leaves, straw and dead weed stubble were collected. During the 2015/16 season stalks and cobs were collected in areas under conventional tillage, no-tillage, either with crop rotation or maize monoculture. Samples were processed, freeze-dried, powedered, had their DNA extracted and the Stenocarpella sp inoculum quantified through qPCR. Soils from the sampled fields were checked for suppressivity to ear and stalk rot -causing fungi. Heat maps were generated with the obtained data. A sub-sample of one kilogram was the minimum necessary to estimate the pathogen survival. The pathogen sporulation was similar among treatments but viability was reduced (27.8-33.3%) in the considered regions. The stubble decomposition was higher in only one location. The sample size, classical and molecular methods allowed the survey of the pathogen in maize stubble and pointed out the role of soybean crop rotation in the reduction of Stenocarpella sp viability. In cultivated areas adopting the conventional tillage system, the pathogen was not detected. However, under no-tillage managed areas, Stenocarpella sp was detected to a lesser extent than in areas adopting no-tillage system with maize monoculture. The results endorse the role of maize stubbles in the survival of Stenocarpella sp. and crop rotation as a useful method to manage the diseases caused by Stenocarpella maydis.
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spelling Stenocarpella spp. inoculum quantification in tropical maize stubbleQuantificação de inóculo de stenocarpella spp. em restos de milho tropicalMilho - Doenças e pragasRotação de culturasPodridão brancaCorn - Diseases and pestsCrop rotationWhite rotZea maysStenocarpella sp.FitopatologiaStenocarpella species (S.maydis and S.macrospora) overwinters in maize stubble and no-till monoculture maize is related to ear and stalk rot outbreaks, but little is known about the factors that contribute to its survival. Therefore this work aimed at determining the contribution of soybean crop rotation and fallow land on pathogen survival and dynamics of maize stubble breakdown, and determining factors that contribute to the pathogens survival. Inn the first article maize fields with history of severe white ear rot were used to determine the stubble sampling size to analyze the pathogen sporulation and viability, as well the maize decomposition. The maize monoculture was compared to one round of soybean rotation and fallow. In the second article, maize fields were selected in the maize growing areas in the state of Minas Gerais for sampling maize stubbles. During the offseason, maize stalks, grains, cobs, fallen maize leaves, straw and dead weed stubble were collected. During the 2015/16 season stalks and cobs were collected in areas under conventional tillage, no-tillage, either with crop rotation or maize monoculture. Samples were processed, freeze-dried, powedered, had their DNA extracted and the Stenocarpella sp inoculum quantified through qPCR. Soils from the sampled fields were checked for suppressivity to ear and stalk rot -causing fungi. Heat maps were generated with the obtained data. A sub-sample of one kilogram was the minimum necessary to estimate the pathogen survival. The pathogen sporulation was similar among treatments but viability was reduced (27.8-33.3%) in the considered regions. The stubble decomposition was higher in only one location. The sample size, classical and molecular methods allowed the survey of the pathogen in maize stubble and pointed out the role of soybean crop rotation in the reduction of Stenocarpella sp viability. In cultivated areas adopting the conventional tillage system, the pathogen was not detected. However, under no-tillage managed areas, Stenocarpella sp was detected to a lesser extent than in areas adopting no-tillage system with maize monoculture. The results endorse the role of maize stubbles in the survival of Stenocarpella sp. and crop rotation as a useful method to manage the diseases caused by Stenocarpella maydis.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPESConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG)Espécies do gênero Stenocarpella (S.maydis e S.macrospora) sobrevivem na entresafra na palhada de milho e a utilização de plantio direto e em monocultura de milho está relacionada a surtos de podridão branca da espiga e podridão do colmo, mas pouco se sabe sobre os fatores que contribuem para a sua sobrevivência. Portanto, este trabalho teve como objetivo determinar a contribuição de rotação de culturas de soja e pousio na sobrevivência e na dinâmica da decomposição de resíduos de patógenos do milho e determinar fatores que contribuem para a sobrevivência destes patógenos. No primeiro artigo, áreas de milho com história de elevada podridão branca da espiga foram utilizadas para determinar o tamanho da amostragem dos restos culturais do milho, para analisar a esporulação dos agentes patogênicos e viabilidade, bem como a sua decomposição. A monocultura de milho foi comparada à rotação com soja e pousio. No segundo artigo, campos de milho foram selecionados nas áreas de cultivo de milho no Estado de Minas Gerais para amostragem dos restos culturais. Durante a entresafra, caules de milho, grãos, espigas, folhas de milho caídas, palhas e resíduos de plantas daninhas mortas, foram coletadas e durante a safra de 2015/16 caules e espigas foram coletadas em áreas utilizando plantio convencional, plantio direto, seja com rotação de culturas ou de monocultura de milho. As amostras foram processadas, liofilizadas, moídas, o DNA foi extraído e o inóculo de Stenocarpella sp quantificado por qPCR. Os solos das áreas amostradas foram verificados quanto à supressividade aos fungos causadroes de podridão de espiga. Mapas de aquecimento foram construídos com a análise de dados. A sub-amostra de um quilograma foi a menor necessária para estimar a sobrevivência do patógeno. A esporulação do patógeno foi semelhante entre os tratamentos, mas a viabilidade foi reduzida (27,8-33,3%) nas regiões consideradas. A decomposição dos restos culturais foi maior em apenas um local. O tamanho da amostra, os métodos clássicos e moleculares permitiram o levantamento do patógeno em restos culturais de milho e demonstraram o papel de rotação de culturas de soja na redução da viabilidade de Stenocarpella sp. Em áreas cultivadas com o sistema de plantio convencional, o patógeno não foi detectado. No entanto, sob áreas manejadas com rotação de culturas em plantio direto, Stenocarpella sp foi detectada em menor grau do que em as áreas que adotam sistema de plantio direto com monocultivo de milho. Os resultados corroboram o papel de resíduos de milho na sobrevivência de Stenocarpella sp., a rotação de culturas como um método útil para manejar as doenças causadas por Stenocarpella maydis e apontam as variáveis que podem estar contribuindo para o aumento do inóculo do patógeno em áreas de cultivo.Universidade Federal de LavrasPrograma de Pós-Graduação em Agronomia/FitopatologiaUFLAbrasilDepartamento de FitopatologiaMedeiros, Flávio Henrique Vasconcelos deAbreu, Mário Sobral deKohl, JürgenMachado, José da CruzPozza, Edson AmpélioSantos, Heloisa Oliveira dosCarvalho, Eudes de ArrudaPinto, Felipe Augusto Moretti Ferreira2016-08-08T20:02:01Z2016-08-08T20:02:01Z2016-08-082016-07-28info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesisapplication/pdfPINTO, F. A. M. F. Stenocarpella spp. inoculum quantification in tropical maize stubble. 2016. 96 p. Tese (Doutorado em Agronomia/Fitopatologia)-Universidade Federal de Lavras, Lavras, 2016.http://repositorio.ufla.br/jspui/handle/1/11558enginfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da UFLAinstname:Universidade Federal de Lavras (UFLA)instacron:UFLA2017-08-18T10:49:50Zoai:localhost:1/11558Repositório InstitucionalPUBhttp://repositorio.ufla.br/oai/requestnivaldo@ufla.br || repositorio.biblioteca@ufla.bropendoar:2017-08-18T10:49:50Repositório Institucional da UFLA - Universidade Federal de Lavras (UFLA)false
dc.title.none.fl_str_mv Stenocarpella spp. inoculum quantification in tropical maize stubble
Quantificação de inóculo de stenocarpella spp. em restos de milho tropical
title Stenocarpella spp. inoculum quantification in tropical maize stubble
spellingShingle Stenocarpella spp. inoculum quantification in tropical maize stubble
Pinto, Felipe Augusto Moretti Ferreira
Milho - Doenças e pragas
Rotação de culturas
Podridão branca
Corn - Diseases and pests
Crop rotation
White rot
Zea mays
Stenocarpella sp.
Fitopatologia
title_short Stenocarpella spp. inoculum quantification in tropical maize stubble
title_full Stenocarpella spp. inoculum quantification in tropical maize stubble
title_fullStr Stenocarpella spp. inoculum quantification in tropical maize stubble
title_full_unstemmed Stenocarpella spp. inoculum quantification in tropical maize stubble
title_sort Stenocarpella spp. inoculum quantification in tropical maize stubble
author Pinto, Felipe Augusto Moretti Ferreira
author_facet Pinto, Felipe Augusto Moretti Ferreira
author_role author
dc.contributor.none.fl_str_mv Medeiros, Flávio Henrique Vasconcelos de
Abreu, Mário Sobral de
Kohl, Jürgen
Machado, José da Cruz
Pozza, Edson Ampélio
Santos, Heloisa Oliveira dos
Carvalho, Eudes de Arruda
dc.contributor.author.fl_str_mv Pinto, Felipe Augusto Moretti Ferreira
dc.subject.por.fl_str_mv Milho - Doenças e pragas
Rotação de culturas
Podridão branca
Corn - Diseases and pests
Crop rotation
White rot
Zea mays
Stenocarpella sp.
Fitopatologia
topic Milho - Doenças e pragas
Rotação de culturas
Podridão branca
Corn - Diseases and pests
Crop rotation
White rot
Zea mays
Stenocarpella sp.
Fitopatologia
description Stenocarpella species (S.maydis and S.macrospora) overwinters in maize stubble and no-till monoculture maize is related to ear and stalk rot outbreaks, but little is known about the factors that contribute to its survival. Therefore this work aimed at determining the contribution of soybean crop rotation and fallow land on pathogen survival and dynamics of maize stubble breakdown, and determining factors that contribute to the pathogens survival. Inn the first article maize fields with history of severe white ear rot were used to determine the stubble sampling size to analyze the pathogen sporulation and viability, as well the maize decomposition. The maize monoculture was compared to one round of soybean rotation and fallow. In the second article, maize fields were selected in the maize growing areas in the state of Minas Gerais for sampling maize stubbles. During the offseason, maize stalks, grains, cobs, fallen maize leaves, straw and dead weed stubble were collected. During the 2015/16 season stalks and cobs were collected in areas under conventional tillage, no-tillage, either with crop rotation or maize monoculture. Samples were processed, freeze-dried, powedered, had their DNA extracted and the Stenocarpella sp inoculum quantified through qPCR. Soils from the sampled fields were checked for suppressivity to ear and stalk rot -causing fungi. Heat maps were generated with the obtained data. A sub-sample of one kilogram was the minimum necessary to estimate the pathogen survival. The pathogen sporulation was similar among treatments but viability was reduced (27.8-33.3%) in the considered regions. The stubble decomposition was higher in only one location. The sample size, classical and molecular methods allowed the survey of the pathogen in maize stubble and pointed out the role of soybean crop rotation in the reduction of Stenocarpella sp viability. In cultivated areas adopting the conventional tillage system, the pathogen was not detected. However, under no-tillage managed areas, Stenocarpella sp was detected to a lesser extent than in areas adopting no-tillage system with maize monoculture. The results endorse the role of maize stubbles in the survival of Stenocarpella sp. and crop rotation as a useful method to manage the diseases caused by Stenocarpella maydis.
publishDate 2016
dc.date.none.fl_str_mv 2016-08-08T20:02:01Z
2016-08-08T20:02:01Z
2016-08-08
2016-07-28
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/doctoralThesis
format doctoralThesis
status_str publishedVersion
dc.identifier.uri.fl_str_mv PINTO, F. A. M. F. Stenocarpella spp. inoculum quantification in tropical maize stubble. 2016. 96 p. Tese (Doutorado em Agronomia/Fitopatologia)-Universidade Federal de Lavras, Lavras, 2016.
http://repositorio.ufla.br/jspui/handle/1/11558
identifier_str_mv PINTO, F. A. M. F. Stenocarpella spp. inoculum quantification in tropical maize stubble. 2016. 96 p. Tese (Doutorado em Agronomia/Fitopatologia)-Universidade Federal de Lavras, Lavras, 2016.
url http://repositorio.ufla.br/jspui/handle/1/11558
dc.language.iso.fl_str_mv eng
language eng
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Universidade Federal de Lavras
Programa de Pós-Graduação em Agronomia/Fitopatologia
UFLA
brasil
Departamento de Fitopatologia
publisher.none.fl_str_mv Universidade Federal de Lavras
Programa de Pós-Graduação em Agronomia/Fitopatologia
UFLA
brasil
Departamento de Fitopatologia
dc.source.none.fl_str_mv reponame:Repositório Institucional da UFLA
instname:Universidade Federal de Lavras (UFLA)
instacron:UFLA
instname_str Universidade Federal de Lavras (UFLA)
instacron_str UFLA
institution UFLA
reponame_str Repositório Institucional da UFLA
collection Repositório Institucional da UFLA
repository.name.fl_str_mv Repositório Institucional da UFLA - Universidade Federal de Lavras (UFLA)
repository.mail.fl_str_mv nivaldo@ufla.br || repositorio.biblioteca@ufla.br
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