Association of Herbicides for Management of Weed Plants in Pre-emergence of Soybean Culture

One of the big challenges to the soybean cultivation is the control of weed plants, because of the competitive potential that they presente and the resistance index in relation to the herbicides. In front of this, the work had as objective to evaluate the mix of herbicides in tanks to initial control of weed plants in the soybean culture. The experiment was installed in field in sistem of no-tillage in an área that presented the cultute of the wheat as precedente. The design used was that one of randomized blocks, with four repetitions. The herbicide’s treatments used in the test were: glyphosate, glyphosate + (diuron+sulfentrazone), glyphosate + diclosulam, glyphosate + (imazethapyr + flumioxazin), glyphosate + flumioxazin, glyphosate + 2,4-D, glyphosate + S-metolachlor, amônio-glufosinate + (diuron + sulfentrazone). The variable used was phytotoxicity in the culture, weed plants’ control Urochloa plantaginea and Raphanus sp., thousand grains weight and productivity of the soybean. The data were submitted to analysis of variance by the F test and the compared averages by the Scott-Knott test, in 5% of error probability. The phytotoxicity caused by the herbicides in the culture is not significative in the point of decrease the grains yield. The herbicides that presented better control of U. plantaginea were the associations of glyphosate with diuron + sulfetrazone, imazethapyr + flumioxazin and s-metolaclhor. Already in the control of Raphanus sp., the association of diclosulam and imazethapyr + flumioxazin with glyphosate presents results next of 100% of control. The variable thousand grains weight it was not affected by the association of the herbicides. In relation to the soybean grains productivity the herbicides (glyphosate + diclosulam and glyphosate + (imazethapyr + flumioxazin)) that provide low phytotoxicity and high control of the weed plants had their productivity compared to the weeded control.