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Objetivou-se com este trabalho avaliar o controle de Amaranthus deflexus, Ipomoea hederifolia e Cyperus rotundus por meio de associações de herbicidas aplicados sobre palhada de cana-de-açúcar da cultivar RB966928. O experimento foi instalado em área comercial na região de Tarumã – SP, em blocos casualizados, com 7 tratamentos e três repetições. As parcelas foram compostas de cinco linhas de cana-de-açúcar espaçadas de 1,50 m com 5m de comprimento (37,5 m2), sendo a infestação presente natural da área. Os tratamentos foram constituídos por associações de mais de um herbicida em tanque agitador, sendo: tebutiuron+diclosulan (900+123 g i.a. ha-1); tebutiuron+flumioxazina (900+150 g i.a. ha-1); isoxaflutole+imazapique (120+112 g i.a. ha-1); tebutiuron+sulfentrazona (900+900 g i.a. ha-1); tebutiuron+amicarbazona (900+910 g i.a. ha-1); isoxaflutole+hexazinona (120+224 g i.a. ha-1); diuron+hexazinona+sulfometurom metílico (1387+391+33,35 g i.a. ha-1), testemunha no mato e testemunha no limpo. A aplicação foi realizada de forma tratorizada com pressão e volume de caldas constantes de 150 L ha-1, em pré-emergência das plantas daninhas. As avaliações de eficácia de controle foram realizadas aos 30, 60, 90 e 120 dias após o tratamento (DAT). As misturas herbicidas tebutiuron+sulfentrazona (900+900 g i.a. ha-1); tebutiuron+amicarbazona (900+910 g i.a. ha-1); isoxaflutole+hexazinona (120+224 g i.a. ha-1) obtiveram controles satisfatórios das três plantas daninhas simultaneamente em todos períodos de avaliação. A associação de tebutiuron+sulfentrazona (900+900 g i.a. ha-1) foi o único tratamento que atingiu 100% de eficiência de controle para o trio de invasoras aos 120DAT.

Aims: Evaluation of the chemicals in controlling bermudagrass weed and effects on sugarcane selectivity. Study Design: Chamber growth studies: completely randomized design with nine treatments with five replicates. Field studies: Randomized block design with nine treatments with five replicates Place and Duration of Study: Instituto Agronômico, Centro de Cana, São Paulo State, Brazil, between February/2018 and December/2019. Methodology: Bermudagrass chemical control was studied in growth chamber in pots. In the first stage, imazapyr, clomazone, indaziflam, sulfentrazone and the control treatment were studied. In the second stage, imazapyr, clomazone, indaziflam were applied and a treatment with no herbicides was maintained. After 75 days of imazapyr application and 38 days of clomazone and indaziflam, clomazone + indaziflam and clomazone + sulfentrazone were applied, in addition to the control treatment. Sugar cane selectivity study was carried out in the field. Before sugarcane planting, imazapyr, clomazone, indaziflam were applied. After planting, clomazone + indaziflam and clomazone + sulfentrazone were applied, in addition to the control treatment. Results: Clomazone at 1050.0 g ha-1 applied as pre plant at 38 days before planting followed by clomazone at 1050.0 g ha-1 plus sulfentrazone at 650.0 g ha-1 applied 2 days after sugar cane planting was the best treatment for bermudagrass control and yield of the crop. Other viable options for control involved clomazone plus sulfentrazone used after imazapyr or indaziflam.