Interaction and efficacy of metusulfuron-methyl and glyphosate tank mixtures

Abstract

The most common solution for problems on weed control in agricultural system of production is the inclusion of alternative herbicides, applied isolated or in tank mixtures. Thus, this work was carried out with the objective of evaluating the efficacy and interaction of metsulfuron‑methyl and glyphosate tank mixtures for weed control. For that, two independent trials were performed, evaluating different bioindicators, being one monocotyledonous (sourgrass – Digitaria insularis) and one dicotyledonous (morning glory – Ipomoea triloba). Treatments were consequence of a factorial combination 5x5, corresponding the first factor to five rates of glyphosate (0, 180, 360, 540 and 720 g a.e. ha-1) and the second factor to five rates of metsulfuron‑methyl (0; 1.2; 2.4; 3.6 and 4.8 g a.i. ha-1). In both experiments, randomized blocks were adopted as experimental design, with six replicates. The mixture of glyphosate and metsulfuron-methyl was considered additive on sourgrass for all the rates considered; for morning glory, including metsulturon-methyl on tank mixture increased total control, however with magnitude lower than expected, what denotes antagonist behavior of mixture.