Based on the hypothesis that glyphosate-tolerant transgenic soybean would need a manganese complementation due to alterations in the absorption and metabolism of this element by the plants, this work aimed to evaluate the interaction of transgenic soybean sprayed with glyphosate and manganese foliar fertilization. The experiment was carried out under field conditions in the agricultural year 2007/2008 on the UNESP Campus Teaching, Research and Production Farm in Jaboticabal, São Paulo, Brazil. An experiment was arranged in a randomized block design, in a factorial scheme (4 x 4), with four replications. Four weed controls [glyphosate (c.p. Roundup Ready) at 0.72 and 1.20 kg ha-1 of equivalent acid; fluazifop-p-butyl plus fomesafen (c.p. Fusiflex) at 0.25 plus 0.25 kg ha-1 and under mechanical control, without herbicide] and four manganese rates (0, 42, 84 and 126 g ha-1) were applied on the soybean leaf. The treatments did not significantly affect grain yield, manganese concentration in the soil, height and dry matter of the soybean plants. Only the mixture fluazifop-p-butyl plus fomesafen caused visible injuries in the plants. However, the symptoms were restricted to the leaves that intercepted spraying. The herbicide treatments did not differ from the control for 100 grain mass, although the plants treated with glyphosate 0.72 kg ha-1 presented less grain mass. Manganese application did not influence element concentration in the plant treated with glyphosate and under mechanical control. Therefore, glyphosate did not impair manganese absorption or metabolism by the plant. Growth and development of the herbicide-treated plants were statistically similar to those of the plants not treated with herbicides.
foliar application; micronutrients; Mn; Roundup Ready; Glycine max
