CONTROLE QUÍMICO DE TRAPOERABA (Commelina benghalensis) EM DESSECAÇÃO PRÉ-PLANTIO DA CULTURA DA SOJA

Abstract

The soybean is the main crop in terms of area and production volume in Brazil. Weeds are one of the principal issues that affect soybean production, promoting loses in target from 0-90%. Trapoeraba (Commelina benghalensis) stands out among plants specifically infesting soybean crops due its frequency of occurrence in agricultural areas and its natural tolerance to the herbicide glyphosate. Burndown before soybean sowing is a key operation for the management of trapoeraba, as it is the moment when there is the possibility of using a greater number of herbicides, changing this weed control prior to the crop installation. In this way, the purpose was to evaluate the efficiency of herbicides associated with glyphosate in the burndown, as well as the influence of the treatments on the yield and productivity components of the soybean crop. The experimental design was randomized blocks, with 7 herbicide treatments and 3 replications. Among the herbicides applied, carfentrazone-ethyl had the greatest phytotoxicity effect and post-emergence control of trapoeraba plants but showed regrowth throughout the crop development. The herbicide Halauxifen-methyl + Diclosulam proved to be a good tool for the management of trapoeraba in both applied modalities, with and without sequential. The treatment with sequential application of glufosinate ammonium proved to be the most efficient in the results of the evaluations, but it did not result in an increase in productivity of the soybean crop. No differences were observed in yield components depending on the herbicide application in pre-sowing of the soybean crop.