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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Extrato de casca de café, óleo essencial de tomilho e acibenzolar-S-metil no manejo da cercosporiose-do-cafeeiro(Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2008-10) Pereira, Ricardo Borges; Alves, Eduardo; Júnior, Pedro Martins Ribeiro; Resende, Mário Lúcio Vilela de; Lucas, Gilvaine Ciavareli; Ferreira, Josimar BatistaO objetivo deste trabalho foi avaliar o efeito de concentrações de extrato de casca de café, óleo essencial de tomilho e acibenzolar-S-metil na germinação, no crescimento micelial e no desenvolvimento in vivo de Cercospora coffeicola, além de caracterizar a efi ciência deles como indutores de resistência, e determinar a atividade da enzima peroxidase e o acúmulo de lignina nos tecidos de cafeeiro. O extrato de casca de café não afetou a germinação, entretanto, inibiu o crescimento micelial proporcionalmente ao aumento das concentrações. O óleo essencial de tomilho inibiu a germinação e o crescimento micelial com o aumento das concentrações. O extrato de casca de café e o acibenzolar-S-metil não afetaram a germinação nem o desenvolvimento dos tubos germinativos, diferentemente do óleo essencial de tomilho. Mudas tratadas com acibenzolar-S-metil, extrato de casca de café e óleo essencial de tomilho, apresentaram picos de atividade da peroxidase aos 2 e 11, 7 e 11 e, 2 e 9 dias após a aplicação dos tratamentos, respectivamente. Os tratamentos não diferiram quanto à concentração de lignina. Extrato de casca de café e acibenzolar-S-metil induziram resistência em mudas de cafeeiro contra C. coffeicola e o óleo essencial de tomilho apresentou efeito tóxico ao patógeno.Item Potential of essential oils for the control of brown eye spot in coffee plants(Editora UFLA, 2011-01) Pereira, Ricardo Borges; Lucas, Gilvaine Ciavareli; Perina, Fabiano José; Resende, Mário Lúcio Vilela de; Alves, EduardoThe objectives of this work were to assess the in vitro effect of essential oils extracted from cinnamon, citronella, lemon grass, India clove, tea tree, thyme, neem and eucalyptus on the conidia germination and on mycelial growth of Cercospora coffeicola, and their efficacy to control the brown eye spot in coffee seedlings (cultivars Catucaí 2SL, Catuaí IAC 62 and Mundo Novo 379/19) in a greenhouse, as well as their effects on the initial germination and infection events by scanning electron microscopy. All essential oils promoted the inhibition of conidia germination with increasing concentrations. India clove, cinnamon, neem, thyme and lemon grass oils inhibited the mycelial growth of C. coffeicola. The cinnamon and citronella oils were the most promising for brown eye spot control in all cultivars. In scanning electron microscopy, the cinnamon and citronella oils reduced germination and mycelial development of C. coffeicola in vivo, eight and 16 hours after inoculation, promoting, in some cases, the leakage of the cellular content. Essential oils of cinnamon and citronella reduced the incidence and severity of brown eye spot, in addition to presenting direct toxicity to the pathogen.Item Citronella essential oil in the control and activation of coffee plants defense response against rust and brown eye spot(Editora UFLA, 2012-07) Pereira, Ricardo Borges; Lucas, Gilvaine Ciavareli; Perina, Fabiano José; Ribeiro Júnior, Pedro Martins; Alves, EduardoThe rust and brown eye spot are the main coffee diseases. The losses are due to intense defoliation of plants, which has reduced its production and longevity. The brown eye spot also occurs in fruits, with negative effects on the beverage quality. Some essential oils have presented promising results in the control of plant diseases, as an alternative to the use of fungicides. The objective of this study was to evaluate citronella essential oil in the control of rust and brown eye spot and in the activation of coffee plants defense responses. Twelve-month-old plants were sprayed with citronella oil 1000 μL L -1 , acibenzolar-S-methyl 200 mg L -1 and tebuconazole fungicide 200 mg L -1 . Plants were inoculated with Hemileia vastatrix and Cercospora coffeicola seven days later. The application was repeated after 30 days. Plants with five months were sprayed with the same treatments to assess the induced defense responses. Citronella oil controlled rust and brown eye spot with efficiencies of 47.2% and 29.7%, respectively, while tebuconazole presented control of 96.5% and 90.5%, respectively. Acibenzolar-S-methyl reduced brown eye spot by 55.9% and showed no significant control of rust. Citronella oil increased peroxidase and chitinase activities in five months coffee plants 336, and 24 and 336 hours after spraying, respectively. Acibenzolar-S-methyl increased peroxidase, chitinase and β -1,3-glucanase activities 192, 288 and 336; 24 and; 240 hours after spraying, respectively. The treatments did not increase accumulation of phenols, but a significant increase in lignin was observed in plants sprayed with citronella oil.Item Acibenzolar-s-metil no controle da ferrugem e da cercosporiose do cafeeiro em condições de campo(Editora UFLA, 2013-01) Fernandes, Luiz Henrique Monteiro; Resende, Mário Lúcio Vilela de; Pereira, Ricardo Borges; Costa, Bruno Henrique Garcia; Monteiro, Ana Cristina Andrade; Ribeiro Júnior, Pedro MartinsObjetivou-se, neste trabalho, avaliar o efeito do indutor de resistência acibenzolar-S-metil (ASM), associado ou não com fungicida à base de ciproconazol + azoxystrobin, no controle da ferrugem e cercosporiose do cafeeiro em condições de campo. O ensaio foi realizado em dois anos safra (2007/2008 e 2008/2009), em plantio comercial com a cultivar Mundo Novo. Os tratamentos utilizados foram: ASM (25 g ha -1 ) aplicado mensalmente 5 vezes (dezembro a abril de cada ano safra); fungicida (500 mL ha -1 ) e a mistura fungicida (500 mL ha -1 ) + ASM aplicados 3 vezes (dezembro, fevereiro e abril de cada ano safra); a mistura fungicida (500 mL ha -1 ) aplicado 3 vezes (dezembro, fevereiro e abril de cada ano safra) + ASM aplicado 5 vezes (dezembro a abril de cada ano safra); a mistura fungicida (750 mL ha -1 ) aplicados 2 vezes (dezembro e março de cada ano safra) + ASM aplicado 5 vezes (dezembro a abril de cada ano safra) e testemunha. O controle da ferrugem (84%) proporcionado pelo ASM foi estatisticamente igual ao tratamento com o fungicida (94%) no ano de safra baixa (2008/2009), quando a intensidade das doenças não foi tão elevada quanto no ano de safra alta (2007/2008). No ano de safra alta, o ASM não controlou a cercosporiose, enquanto que no ano de safra baixa esse produto controlou a cercosporiose (77%) de forma inferior ao fungicida (92%) e suas misturas (89 a 94%). Em ano de safra baixa, o ASM pode ser usado no controle da ferrugem e cercosporiose do cafeeiro e apresentou compatibilidade com o fungicida ciproconazol + azoxystrobin.Item Acibenzolar-s-methyl in rust and blotch control in field conditions(Editora UFLA, 2013-01) Fernandes, Luiz Henrique Monteiro; Resende, Mário Lúcio Vilela de; Pereira, Ricardo Borges; Costa, Bruno Henrique Garcia; Monteiro, Ana Cristina Andrade; Ribeiro Júnior, Pedro MartinsThe objective of this study was to evaluate the effect of acibenzolar-S-methyl (ASM) resistance inductor, associated or not with the fungicide azoxystrobin + cyproconazole base, the control of Cercospora leaf rust and coffee under field conditions. The study was conducted during two harvest years (2007/2008 and 2008/2009), in commercial planting of the Mundo Novo cultivar. Used treatments were: ASM (25 g ha -1 ) applied omnthly five times (from December to April of each harvest year); fungicide (500 mL ha -1 ) and the mixture fungicide (500 mL ha -1 ) + ASM applied three times (December, February and April of each harvest year); the mixture fungicide (500 mL ha -1 ) applied three times (December, February and April of each harvest year) + ASM applied five times (December to April of each harvest year); the mixture fungicide (750 mL ha -1 ) applied two times (December and March of each harvest year) + ASM applied five times (December to April of each harvest year) and witness. Rust control (84%) given by ASM was statistically equal to the treatment with fungicide (94%) in the low harvest year (2008/2009), when diseases intensity was not as high as in the high harvest year (2007/2008). In the high harvest year, ASM did not control blotch, while in the low harvest year this product controlled blotch (77%) at an inferior rate compared to fungicide (92%) and mixtures (89 to 94%). In low harvest years, ASM can be used in rust and blotch control for coffee trees and showed compatibility with the fungicide ciproconazole + azoxystrobin.