Atrazine and terbuthylazine in association with nicosulfuron and mesotrione in the management of different species of the genus Urochloa

Abstract

The Integrated Crop-Livestock (ILP) systems have gained relevance in Brazil for reconciling the production of meat and/or milk with that of grains, in order to extract mutual benefits for both cultures. In this sense, the corn-brachiaria consortium has proved to be an excellent option for ILP systems, as it allows the production of high amounts of straw and the increase in organic matter contents in the soil. Therefore, the objective of this work will be to evaluate the effects of treatments mesotrione + atrazine + mineral oil, mesotrione + terbuthylazine + mineral oil, nicosulfuron + atrazine + mineral oil and nicosulfuron + terbuthylazine + mineral oil, applied at different doses, on grain yield. of maize and the accumulation of dry biomass of the aerial parts of Urochloa brizantha and U. ruziziensis. The experiment will be carried out at UFSCar de Araras in a randomized block design with 4 replications. The corn will be planted at a spacing of 0.90 m, with an intercalary line of forage (U. brizantha or U. ruziziensis), and the application of the herbicide treatments will take place 15 days after corn emergence, using a backpack sprayer. Forage intoxication will be evaluated at 7, 14, and 21 days after application of treatments (DAA), and the percentages of weed control will be determined at 21 DAA. At 30 DAA and at the end of the corn crop cycle, the accumulation of dry biomass of the aerial part of the plants of U. brizantha and U ruziziensis will be determined, and for this, samples will be collected in 1 m2. The heights of the corn plants and the insertion of the first ear will be measured using a graduated measuring tape, and the grain yield will be determined by manually harvesting the ears. Subsequently, statistical analyzes will be carried out from the collected data. (AU)