The s-metolachlor is an excellent option for bean growers, since it provides effective control of grass and some broad leaf weeds. Even so, toxicity problems caused by this herbicide to the bean plants are observed frequently under field conditions. The objective of this work was to evaluate the agronomic performance and tolerance of five bean cultivars (Jalo Precoce, Xamego, Carioca, Rudá, and Pérola) to s-metolachlor, under two irrigation conditions close to herbicide application. The work was conducted in the field, in the rainy season in a Cambic Podzolic soil, terrace phase, with 35 dag kg-1 of clay and 3.6 dag kg-1 of organic matter. Two experiments were carried out differing only in the methodology used by each, i.e., in the first, a 20 mm water lamina was applied immediately before the herbicide treatment and in the second, the same water lamina was applied immediately after herbicide application. Six smetolachlor doses (0; 0.48; 0.72; 0.96; 1.20; and 1.92 kg ha-1), were evaluated associated to the five cultivars mentioned. S-metolachlor toxicity was not observed in the doses evaluated in none of the bean cultivars, regardless of the irrigation conditions before and after herbicide application.
Phaseolus vulgaris; toxicity; irrigation
