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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Resultados da Pesquisa
Item Reprodução de Meloidogyne exigua em cultivares de cafeeiros resistentes e suscetíveis(Sociedade Brasileira de Fitopatologia (SBF), 2005-05-12) Salgado, Sônia M. Lima; Resende, Mário Lúcio V.; Campos, Vicente P.A resistência do cafeeiro (Coffea arabica) Iapar-59 a Meloidogyne exigua foi comparada com a cultivar IAC-Apoatã, empregada como padrão de resistência, e com as cultivares suscetíveis Mundo Novo (IAC 379-19), Catuaí (IAC 62) e Tupi (IAC 1669-33). Plantas de um ano de idade foram inoculadas com 10.000 ovos de M. exigua. Aos 93 dias da inoculação avaliou-se a reprodução de M. exigua através do número de galhas (NG), número de ovos (NO), fator de reprodução (FR), reducão no fator de reprodução e comportamento dos cafeeiros. Menor reprodução de M. exigua foi igualmente (P<0,05) observada nos cafeeiros Iapar-59 e Apoatã, nos quais o IG, NO e FR foram menores do que aqueles observados nas cultivares Mundo Novo, Catuaí e Tupi. Maior redução no FR de M. exigua ocorreu nos cafeeiros Apoatã e Iapar-59, indicando a reação de resistência do Iapar-59.Item Ocorrência de Meloidogyne coffeicola em cafeeiros do município de Coromandel, Região do Alto Paranaíba em Minas Gerais(Sociedade Brasileira de Fitopatologia (SBF), 2004-04-26) Castro, José M. C.; Campos, Vicente P.; Dutra, Marcos R.Coffee (Coffea arabica) plantations showing symptoms of decline, such as peeled and rough roots and fewer side rootlets were observed in the State of Minas Gerais, Brazil. Meloidogyne sp. females were obtained from thicker roots, and processed for perineal patterns and a-esterase electrophoresis analysis. It was concluded that M. coffeicola was the causal agent. The nematode incidence was occurring with field symptom patterns similar to those observed on coffee plantations of the State of Paraná, where most damage caused by M. coffeicola has been reported.Item Ocorrência de Meloidogyne paranaensis em cafeeiros na região do Alto Paranaíba em Minas Gerais(Sociedade Brasileira de Fitopatologia (SBF), 2003-03-24) Castro, José M. C.; Campos, Vicente P.; Naves, Rosemeire L.Coffee (Coffea arabica) plantations showing symptoms of decline, with peeled and rough roots and fewer side rootlets were observed in the State of Minas Gerais, Brazil. Meloidogyne spp. females were obtained from the thicker roots and processed for perineal patterns and α-esterase electrophoresis analysis. Meloidogyne paranaensis was determined to be the main cause of the decline. The incidende and field symptom patterns found were similar to those observed on coffee plantations in the State of São Paulo and Paraná, where most damage caused by M. paranaensis has been reported.Item Volatile organic compounds for the control of Meloidogyne exigua in Coffea arabica(Sociedade Brasileira de Fitopatologia, 2013) Silva, Willian R. J.; Machado, Alan R. T.; Campos, Viviane A. C.; Zeri, Ana C. M.; Campos, Vicente P.; Oliveira, Denilson F.Meloidogyne exigua is a plant-parasitic nematode that causes great losses to coffee farmers. Thus, to contribute to the development of new products to control this parasite, the present work studied the effect of volatile organic compounds (VOC) on the nematode and coffee plants (Coffea arabica), since these compounds are known to be used in plant defense against other agronomical pests. The number of galls of M. exigua was reduced when the aerial part of coffee plants was sprayed with combinations of methyl jasmonate + jasmone, (Z)-hex-3-en-1-ol + (E)-hex-3-en-1-ol + (Z)-hex-2-en-1-ol + (E)-hex-2-enal, (E)-hex-2-enyl acetate + hexyl acetate, meso-butane-2,3-diol + butane-1,2-diol + butane-1,3-diol + butane-1,4-diol, 3-hydroxybutan-2-one + 4-hydroxybutan-2-one or linalyl acetate + nerolidol. These VOC also caused alterations in the concentrations of substances such as alkaloids, phenols, amino acids and carbohydrates, in the roots of coffee plants. The findings suggest that these VOC may be explored as potential products for the control of M. exigua in coffee plants.Item Reaction of coffee genotypes to different populations of Meloidogyne spp.: detection of a naturally virulent M. exigua population(Sociedade Brasileira de Fitopatologia, 2009) Muniz, Maria de Fátima S.; Campos, Vicente P.; Moita, Antônio W.; Gonçalves, Wallace; Almeida, Maria Ritta A.; Sousa, Fábio Rodrigues de; Carneiro, Regina Maria D. G.The reaction of seven genotypes of Coffea arabica to 10 Meloidogyne spp. populations collected mainly from coffee plantations in Brazil and Costa Rica was evaluated under greenhouse conditions. The inoculum consisted of 10,000 eggs per plant. Evaluations were done 8 months after inoculations considering the root fresh weight, gall and egg mass indices, number of eggs per gram of root and reproduction factor (RF). The cultivars Obatã IAC 1669-20, Sarchimor IAC 4361 and Tupi Amarelo IAC 5111 exhibited susceptibility to the four Brazilian M. exigua populations tested. However, cv. Tupi Vermelho IAC 1669-33 revealed resistance (RF value of 0.7) to the M. exigua population from Lavras, Minas Gerais State, Brazil. A population of M. exigua from Bom Jesus de Itabapoana, Rio de Janeiro State, Brazil, was highly virulent on cv. IAPAR 59 (RF= 165.7), bearing resistance gene Mex-1, and was also virulent on genotype Paraíso (H 419-5-4-5-2) (RF=396.2). A Meloidogyne sp. population on coffee from Garça, São Paulo State, Brazil, reproduced at low rates (RF ranging from 0.1 to 3.9) on all genotypes. All tested cultivars were susceptible to M. incognita and M. paranaensis. M. mayaguensis of guava from Paraná State, Brazil, reproduced at low rates in all coffee genotypes; however, another population of coffee, from Costa Rica, was more aggressive and showed RF value that ranged from 0.8 to 12.4. Results of this study point for the first time to the ability of a naturally occurring M. exigua population to overcome the resistance conferred by the Mex-1 gene.