Tolerância de cultivares de cana-de-açúcar a herbicidas aplicados em pós-emergência
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Data
2009-01-01
Autores
Souza, Joseane Rodrigues de [UNESP]
Perecin, Dilermando [UNESP]
Azania, Carlos Alberto Mathias
Schiavetto, Ana Regina [UNESP]
Pizzo, Igor Vanzela
Candido, Liliam Silvia [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Instituto Agronômico de Campinas
Resumo
O presente trabalho teve por objetivo avaliar a tolerância de cultivares de cana-de-açúcar a herbicidas aplicados em pós-emergência inicial da soqueira. O experimento foi implantado em Ribeirão Preto (SP), no ano agrícola de 2007/2008. O delineamento experimental foi de blocos ao acaso, em esquema de parcelas subdivididas com 36 tratamentos em quatro repetições. Foram utilizadas as cultivares IACSP94-2094, IACSP94-2101, IACSP93-3046, IACSP94-4004, RB72454 e a IAC 86-2480 nas parcelas e os herbicidas, constituídos pela mistura pronta de diurom (1170g ha-1) + hexazinona (330 g ha-1); diurom (1865 g ha-1) + hexazinona (234 g ha-1); metribuzim; tebutiuron; amicarbazona e uma testemunha nas subparcelas. Foram avaliados os sintomas visuais de intoxicação, teor relativo de clorofila, eficiência fotoquímica máxima do fotossistema II, altura, estande, qualidade tecnológica da cana e a produção dos colmos. Concluiu-se que as cultivares IACSP94-2094, IACSP94-2101, IACSP93-3046, IACSP94-4004, RB72454 e IAC86-2480 não foram influenciadas pelos herbicidas, apenas ocorreram diferenças inerentes à própria genética. Observou-se apenas leves sintomas de intoxicação na fase inicial de desenvolvimento e não se constatou nenhum prejuízo ao conteúdo de clorofila, avaliado pelo teor relativo de clorofila. No sistema fotossintético houve pequeno prejuízo na fase inicial, quando avaliado pela eficiência fotoquímica máxima do FS II (Fv/Fm), mas que não foi suficiente para prejudicar a altura, o estande, a produção e a qualidade tecnológica das diferentes cultivares de cana-de-açúcar estudadas.
This study aimed to assess the tolerance of cultivars of sugarcane to herbicides applied in post-emergence initial of ratoon. The experiment was carried in Ribeirão Preto, SP, Brazil, in the agricultural year 2007/2008. The experimental design was the randomized blocks, in split-plots, 36 treatments and four replications. It was used the cultivars IACSP94-2094, IACSP94-2101, IACSP93-3046, IACSP94-4004, RB72454 and IAC86-2480 in plots and herbicides, were made by mixture ready to diuron (1170 g ha-1) + hexazinone (330 g ha -1); diuron (1865 g ha-1) + hexazinone (234 g ha-1); metribuzin; tebuthiuron; amicarbazone and a control in the sub-plots. The intoxication symptoms of visual, relative content of chlorophyll and photochemical efficiency of PS II, height, stand, technological quality of sugarcane and production the culms. It was concluded the cultivars IACSP94-2094, IACSP94-2101, IACSP93-3046, IACSP94-4004, RB72454 and IAC86-2480 were not affected by herbicides, only showed differences inherent in the genetics. In all cultivars, there was only mild intoxication symptoms of visual at the initial stage of development and there was not any damage to the content of chlorophyll, measured by relative content chlorophyll. The photosynthetic system showed little damage in the initial phase, when measured by the photochemical efficiency of PS II (Fv/Fm), but that was not enough to constrain the height, stand, production and technology quality of different cultivars of sugarcane studied.
This study aimed to assess the tolerance of cultivars of sugarcane to herbicides applied in post-emergence initial of ratoon. The experiment was carried in Ribeirão Preto, SP, Brazil, in the agricultural year 2007/2008. The experimental design was the randomized blocks, in split-plots, 36 treatments and four replications. It was used the cultivars IACSP94-2094, IACSP94-2101, IACSP93-3046, IACSP94-4004, RB72454 and IAC86-2480 in plots and herbicides, were made by mixture ready to diuron (1170 g ha-1) + hexazinone (330 g ha -1); diuron (1865 g ha-1) + hexazinone (234 g ha-1); metribuzin; tebuthiuron; amicarbazone and a control in the sub-plots. The intoxication symptoms of visual, relative content of chlorophyll and photochemical efficiency of PS II, height, stand, technological quality of sugarcane and production the culms. It was concluded the cultivars IACSP94-2094, IACSP94-2101, IACSP93-3046, IACSP94-4004, RB72454 and IAC86-2480 were not affected by herbicides, only showed differences inherent in the genetics. In all cultivars, there was only mild intoxication symptoms of visual at the initial stage of development and there was not any damage to the content of chlorophyll, measured by relative content chlorophyll. The photosynthetic system showed little damage in the initial phase, when measured by the photochemical efficiency of PS II (Fv/Fm), but that was not enough to constrain the height, stand, production and technology quality of different cultivars of sugarcane studied.
Descrição
Palavras-chave
Saccharum spp., Selectivity, intoxication symptoms, Phytotoxicity, Saccharum spp., Seletividade, sintomas de intoxicação, Fitotoxicidade
Como citar
Bragantia. Instituto Agronômico de Campinas, v. 68, n. 4, p. 941-951, 2009.