Revista Brasileira De Herbicidas 2016; 15(4): 296-302
Period of rain after saflufenacil application in controlling floating aquatic macrophytes
Saflufenacil herbicide can be one more alternative to control aquatic environment weeds, but at the time of or after the application of the herbicide bad weather such as rain, may invalidate the chemical control of problematic species occurring in this environment. Thus, the goal of this study was to evaluate the occurrence of different rain periods after applying saflufenacil herbicide to control water hyacinth and water lettuce plants. The study was conducted in plastic pots with 2.5 water liter capacity and kept in greenhouse conditions. The experimental design was completely randomized with nine treatments and four replications. Treatments consisted of rainfall simulation performed through a stationary sprayer in periods after the application of the herbicide: 0; 0.25; 0.5; 1; 2; 4; 6; and 12 hours, as well as a period without rain. Saflufenacil was applied at a 33.6 g ha-1 dose and evaluations were performed 7, 14, 21, 28 and 35 days after herbicide application. The occurrence of rain at intervals of more than two hours after the application of saflufenacil did not change the effectiveness on water hyacinth. As for water lettuce plants, there was an effective control with a minimum of four hours for the occurrence of rain after application of the herbicide. Finally, for all plants, periods equal to or higher than six hours after the application of saflufenacil provided total control over water hyacinth and water lettuce plants.
Keywords: chemical control; Eichhornia crassipes; Pistia stratiotes
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