The objective of this study were to identify incompatibilities in mixtures of herbicides applied in common bean crops and assess the effects of herbicide interactions on weed control. Experiments I e II were conducted in a completely randomized design, with four replications, using a 4×4 factorial arrangement consisted of four herbicides (applied alone or in combinations) and four evaluation times (0, 1, 2, and 3 hours). a physical evaluation of the syrup was carried out. Experiments III e IV were conducted under the same design but with solution applied immediately after preparation and evaluations of weed control at 7, 14, and 28 days after application. The results showed homogeneity for all formulations, but persistent foam formation in some cases. No incompatibility was found for the herbicide mixtures. Satisfactory control of Eleusine indica and Euphorbia heterophylla was not achieved in Experiment III (bentazon and imazamox, alone or in combination) due to the antagonistic effect of the herbicide combination. Combining bentazon and imazamox was promising for controlling Cyperus esculentus and Bidens pilosa, while combining fomesafen and imazamox was promising for controlling all evaluated weed species.

Keywords: Herbicide incompatibility, sustainable production, environmental preservation, spray solution stability.