Avaliação da seletividade e eficácia de misturas formuladas de bentazon + acifluorfen em soja

A trial was carried out to test the efficacy and selectivity of different formulations and doses of bentazon with acifluorfen, applied in post emergence of soybean (cv. Doko). The following treatments were tested in a sandy Latosoil, in Prudente de Morais, Brazil: bentazon+acifluorfen (480+204 g/ha and 600+255 g/ha) with or without mineral oil (0,25% v/v); bentazon+acifluorfen (480+168 g/ha and 600+210 g/ha) with or without mineral oil (0,25%v/v); and bentazon +acifluorfen 600+160 g/ha and weeded and no weeding checks. Independently of the doses and formulations (with or without mineral oil) all chemicals provided efficient control of Amaranthus hybridus, Galinsoga parviflora and Solanum americanum. Significant differences were not observed among the productivities for the several chemical treatments, but reduced the interference of weeds caused an average decrease in yield of 1445 kg/ha in relation to the weed check. These was no difference between treatments concerning plant density, plant height, height of first pod and weight of 100 seeds. All tested treatments were selective for the soybean.