Agronomic performance of RR® soybean as a function of glifosato doses

Abstract

The use of glyphosate herbicide affects nutritional balance, nodulation, biochemical, physiological factors and consequently can affect the components of production of the RR^® soybean crop. The objective of this work was to evaluate the effect of glifosato doses on the phytotoxicity and agronomic traits of RR^® soybean cultivars. The experimental design was in randomized blocks, arranged in a 3 x 6 factorial scheme, with three replications. The treatments consisted of three RR^® soybean cultivars (CD 250, TMG 1174 and V-MAX) and six doses of the herbicide glifosato (0, 960, 1920, 2880, 3840, 4800 g e.a. ha^-1), were used Roundup Ready^® commercial product. They were evaluated: aerial dry matter, phytotoxicity, plant height, first pod insertion, one thousand grain mass and grain yield. The application of increasing doses of glifosato up to 4800 g e.a. ha^-1 caused phytotoxicity in soybean plants, however, they did not cause enough damage to reduce the agronomic characteristics of soybean. The highest productivity of the grains was verified for cultivar TMG 1174 RR in Lavras and for cultivar V-MAX RR in Patos de Minas.