Ferrugem alaranjada da cana-de-açúcar: viabilidade técnica e econômica do controle químico, e curvas de progresso da doença sob condições naturais de cultivo.
Carregando...
Data
2017-11-22
Autores
Zeneratto, Marcos Antonio
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
A ferrugem alaranjada da cana-de-açúcar (FA), causada por Puccinia kuehnii, é responsável por superior a 40% na produtividade de genótipos de cana-de-açúcar suscetíveis e intermediários. Nesse estudo foram realizados três experimentos. No experimento E1 foi avaliado o efeito do número de aplicações de fungicida piraclostrobina + epoxiconazole (PE) no município de Olímpia-SP, em E2 foi avaliado o efeito do número de aplicações de fungicida piraclostrobina + epoxiconazole (PE) no município de Catigua-SP, ambos em épocas distintas, e em E3 foi avaliado o efeito do volume de calda de PE no controle da doença. A partir dos dados obtidos nos experimentos E1 e E2, foi também avaliada a viabilidade econômica do controle da FA da cana-de-açúcar. Os experimentos foram realizados em dois locais, Olímpia e Catiguá, Estado de São Paulo, sendo empregada a cultivar SP81-3250, em quarto ciclo, após o terceiro corte, em estádio de desenvolvimento (Elongação do colmo; Crescimento intenso; Início do acúmulo de sacarose) da cultura. Em E1 e E2 usou-se o delineamento experimental em blocos ao acaso (DBC), com quatro tratamentos, sendo 0 (testemunha), 1, 2 e 3 aplicações. Cada parcela foi constituída por quatro linhas de 8 metros, espaçadas de 1,5 metros. Foram realizadas sete avaliações, com as quais determinou-se a severidade, a partir das quais foi obtida a área abaixo da curva de progresso da doença (AACPD). Também foi estimado o rendimento de colmos, expresso em tonelada de colmos por hectare (TCH). Em E3 foi adotado procedimento semelhante, cujos tratamentos foram representados pelos volumes 0 (testemunha), 80, 160 e 240 L calda ha-1. Em E1 e E2, a partir de dados relativos a aumento de rendimento de colmos (TCH) foi estimado a viabilidade econômica. Em E1 e E2, verificou-se que independente das variáveis avaliadas todos os tratamentos foram superiores à testemunha. Houve relação entre AACPD e produtividade. O controle da doença, nos melhores tratamentos, resultou em aumento de produtividade da ordem de 18,7 e 25,5 t cana ha-1, respectivamente para Olímpia e Catiguá. Em E3 observou-se que mesmo em baixos volumes de calda, como 80 L calda ha-1, houve eficiente controle da doença, com indicação de maior otimização do uso da água e, possivelmente, com redução do custo operacional e de controle da doença. A viabilidade econômica do controle de FA foi demonstrado, com retorno de R$2,38 por Real investido.
The orange rust of sugarcane (FA), caused by Puccinia kuehnii, is responsible for over 40% in the yield of susceptible and intermediate sugarcane genotypes. Three experiments were performed in this study. In the E1 experiment, the effect of the number of applications of fungicide pyraclostrobin + epoxiconazole (PE) in the municipality of Olímpia-SP, in E2, was evaluated the effect of the number of applications of fungicide pyraclostrobin + epoxiconazole (PE) in the municipality of Catigua-SP, both at different times, and in E3 the effect of the volume of PE syrup on disease control was evaluated. From the data obtained in experiments E1 and E2, the economic viability of sugarcane FA control was also evaluated. The experiments were carried out at two locations, Olímpia and Catiguá, State of São Paulo, and the cultivar SP81-3250 was used, in the fourth cycle, after the third cut, at the development stage (Elongation of the stem, intense growth; sucrose) of the culture. In E1 and E2, the experimental design in randomized blocks (DBC) was used, with four treatments, being 0 (control), 1, 2 and 3 applications. Each plot was constituted by four lines of 8 meters, spaced of 1.5 meters. Seven evaluations were performed, with which the severity was determined, from which the area under the disease progress curve (AACPD) was obtained. The yield of stalks, expressed in ton of stems per hectare (TCH), was also estimated. In E3 a similar procedure was adopted, whose treatments were represented by volumes 0 (control), 80, 160 and 240 L syrup ha-1. In E1 and E2, data on increased yield of stalks (TCH) were estimated economically viability. In E1 and E2, it was verified that regardless of the evaluated variables all the treatments were superior to the control. There was a relationship between AACPD and productivity. The control of the disease, in the best treatments, resulted in an increase of productivity of 18.7 and 25.5 t cana ha-1, respectively, for Olímpia and Catiguá. In E3, it was observed that even in low volumes of syrup, such as 80 L syrup ha-1, there was an efficient control of the disease, with an indication of greater optimization of water use and, possibly, reduction of operational cost and disease control. The economic viability of the AF control was demonstrated, with a return of R $ 2.38 per invested Real.
The orange rust of sugarcane (FA), caused by Puccinia kuehnii, is responsible for over 40% in the yield of susceptible and intermediate sugarcane genotypes. Three experiments were performed in this study. In the E1 experiment, the effect of the number of applications of fungicide pyraclostrobin + epoxiconazole (PE) in the municipality of Olímpia-SP, in E2, was evaluated the effect of the number of applications of fungicide pyraclostrobin + epoxiconazole (PE) in the municipality of Catigua-SP, both at different times, and in E3 the effect of the volume of PE syrup on disease control was evaluated. From the data obtained in experiments E1 and E2, the economic viability of sugarcane FA control was also evaluated. The experiments were carried out at two locations, Olímpia and Catiguá, State of São Paulo, and the cultivar SP81-3250 was used, in the fourth cycle, after the third cut, at the development stage (Elongation of the stem, intense growth; sucrose) of the culture. In E1 and E2, the experimental design in randomized blocks (DBC) was used, with four treatments, being 0 (control), 1, 2 and 3 applications. Each plot was constituted by four lines of 8 meters, spaced of 1.5 meters. Seven evaluations were performed, with which the severity was determined, from which the area under the disease progress curve (AACPD) was obtained. The yield of stalks, expressed in ton of stems per hectare (TCH), was also estimated. In E3 a similar procedure was adopted, whose treatments were represented by volumes 0 (control), 80, 160 and 240 L syrup ha-1. In E1 and E2, data on increased yield of stalks (TCH) were estimated economically viability. In E1 and E2, it was verified that regardless of the evaluated variables all the treatments were superior to the control. There was a relationship between AACPD and productivity. The control of the disease, in the best treatments, resulted in an increase of productivity of 18.7 and 25.5 t cana ha-1, respectively, for Olímpia and Catiguá. In E3, it was observed that even in low volumes of syrup, such as 80 L syrup ha-1, there was an efficient control of the disease, with an indication of greater optimization of water use and, possibly, reduction of operational cost and disease control. The economic viability of the AF control was demonstrated, with a return of R $ 2.38 per invested Real.
Descrição
Palavras-chave
Fungicida, Manejo, Puccinia kuehnii, Saccharum spp, Fungicide, Management