Selectivity of Herbicides Applied in Preemergence and Diuron in Postemergence for Sesame

Abstract

The expansion of sesame growth has led to one of the biggest challenges in weed management mainly due to the limited options of selective herbicides for the control of eudicots species. This study aimed to evaluate the selectivity of diuron, s-metolachlor or imazethapyr herbicide treatments in isolation, or in a tank mixture, when applied in preemergence only, or association with diuron herbicide sprayed in postemergence during sesame cultivation. Two experiments were carried out under Brazilian Cerrado conditions. In the first experiment, different doses (g ha^-1) of diuron (500 and 750), s-metolachlor (480 and 960) and imazethapyr (40 and 80) were applied in preemergence in isolation or in a tank mixture. In the second experiment, doses (g ha^-1) of the herbicides diuron (500 and 750) and s-metolachlor (480 and 720) were applied in preemergence isolated or in tank mixture, associated or not with diuron (500 g ha^-1) in postemergence. The results indicated that diuron and s-metolachlor applied in isolation or in combination during preemergence are selective to the sesame crop up to the doses of 750 g ha^-1 and 720 g ha^-1, respectively, and when applied in association with diuron at a dose of 500 g ha^-1 in postemergence are also selective for sesame crop.