Eficácia de herbicidas aplicados nas épocas seca e úmida para o controle de Euphorbia heterophylla na cultura da cana-de-açúcar
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Data
2010-12-01
Autores
Correia, N.M [UNESP]
Kronka Jr, B
Título da Revista
ISSN da Revista
Título de Volume
Editor
Sociedade Brasileira da Ciência das Plantas Daninhas
Resumo
Objetivou-se estudar o efeito de herbicidas aplicados em pré e pós-emergência, isolados e em combinações nas épocas seca e úmida, para o controle de leiteiro (Euphorbia heterophylla) na cultura de cana-de-açúcar. O experimento foi desenvolvido no período de agosto de 2008 a junho de 2009, em área de produção comercial de cana-de-açúcar localizada no município de Jaboticabal-SP. O delineamento experimental foi o de blocos ao acaso, com quatro repetições, em esquema de parcela subdividida. Na época seca foram avaliados os herbicidas amicarbazone (1.400 g ha-1), imazapic (147 g ha-1) e sulfentrazone (900 g ha-1), aplicados em 1º/8/2008 após a colheita da cana, e testemunha sem manejo prévio das plantas daninhas. Os herbicidas utilizados na época úmida foram: mesotrione isolado (192 g ha-1) e em mistura (120 g ha-1) com ametryn (1.500 gha-1), atrazine (1.500 gha-1) ou diuron + hexazinone (702 + 198 g ha-1), aplicados em 14/11/2008, além de testemunha capinada e outra sem manejo das plantas daninhas. A aplicação de imazapic na época seca foi eficaz no controle de E. heterophylla, dispensando a complementação de manejo na época úmida. No entanto, para os herbicidas amicarbazone e sulfentrazone houve necessidade da aplicação de mesotrione, isolado ou em mistura com ametryn, atrazine ou diuron + hexazinone, para a manutenção do controle de E. heterophylla na época úmida (de 105 a 230 dias após a aplicação na época seca). Quando não foi realizada a aplicação de herbicida na época seca, constatou-se melhor controle de E. heterophylla na época úmida com o herbicida mesotrione associado a ametryn, atrazine ou diuron + hexazinone do que quando aplicado isoladamente. Apesar dos sintomas visuais de fitointoxicação ocasionados pelos tratamentos mesotrione + ametryn e mesotrione + (diuron + hexazinone) pulverizados na época úmida, nenhum dos manejos adotados ou combinações entre eles interferiu no número de colmos viáveis por metro linear, no diâmetro e na altura de colmos de cana-de-açúcar.
An experiment was carried out in a commercial sugarcane plantation area in Jaboticabal, São Paulo, Brazil, from August 2008 to June 2009 to evaluate the effect of herbicides applied in preemergence and postemergence, alone and combination, during the dry and wet seasons, for poinsettia control (Euphorbia heterophylla). The experiment was arranged in a randomized block design in split-plot, and four replications. Three herbicide treatments [amicarbazone (1.4 kg ha-1),imazapic (0.147 kg ha-1) and sulfentrazone (0.9 kg ha-1 plus 0.2 kg ha-1),applied on August 01, 2008 after sugarcane harvest, and one treatment without herbicide were tested. The herbicides used during the wet season were: mesotrione alone (0.192 kg ha-1), and in mixture (0.12 kg ha-1) with ametryn (1.5 kg ha-1), atrazine (1.5 kg ha-1) or diuron plus hexazinone (0.702 plus 0.198 kg ha-1), applied in postemergence on November 14, 2008, and two treatments without herbicide. The application of imazapic during the dry season was efficient for E. heterophylla control, without the need of management complementation during the wet season. However, the amicarbazone and sulfentrazone treatments required mesotrione application, alone or mixed with ametryn, atrazine or diuron, plus hexazinone to control E. heterophylla during the wet season (105 to 230 days after application during the dry season). Without herbicide application during the dry season, mesotrione mixed with ametryn, atrazine or diuron plus hexazinone resulted in a better weed control than when applied alone. Despite the visual symptoms of phytointoxication caused by the treatments mesotrione plus ametryn and mesotrione plus (diuron plus hexazinone), none of the types of management adopted or combinations between them interfered in the number of viable stalk by linear meter, and in stalk diameter and height in sugarcane.
An experiment was carried out in a commercial sugarcane plantation area in Jaboticabal, São Paulo, Brazil, from August 2008 to June 2009 to evaluate the effect of herbicides applied in preemergence and postemergence, alone and combination, during the dry and wet seasons, for poinsettia control (Euphorbia heterophylla). The experiment was arranged in a randomized block design in split-plot, and four replications. Three herbicide treatments [amicarbazone (1.4 kg ha-1),imazapic (0.147 kg ha-1) and sulfentrazone (0.9 kg ha-1 plus 0.2 kg ha-1),applied on August 01, 2008 after sugarcane harvest, and one treatment without herbicide were tested. The herbicides used during the wet season were: mesotrione alone (0.192 kg ha-1), and in mixture (0.12 kg ha-1) with ametryn (1.5 kg ha-1), atrazine (1.5 kg ha-1) or diuron plus hexazinone (0.702 plus 0.198 kg ha-1), applied in postemergence on November 14, 2008, and two treatments without herbicide. The application of imazapic during the dry season was efficient for E. heterophylla control, without the need of management complementation during the wet season. However, the amicarbazone and sulfentrazone treatments required mesotrione application, alone or mixed with ametryn, atrazine or diuron, plus hexazinone to control E. heterophylla during the wet season (105 to 230 days after application during the dry season). Without herbicide application during the dry season, mesotrione mixed with ametryn, atrazine or diuron plus hexazinone resulted in a better weed control than when applied alone. Despite the visual symptoms of phytointoxication caused by the treatments mesotrione plus ametryn and mesotrione plus (diuron plus hexazinone), none of the types of management adopted or combinations between them interfered in the number of viable stalk by linear meter, and in stalk diameter and height in sugarcane.
Descrição
Palavras-chave
combinação de herbicida, leiteiro, planta daninha, palha, Saccharum officinarum, herbicide combination, poinsettia, weed, mulch, Saccharum officinarum
Como citar
Planta Daninha. Sociedade Brasileira da Ciência das Plantas Daninhas , v. 28, n. 4, p. 853-863, 2010.