WEED CONTROL IN SOYBEAN CROP WITH GLYPHOSATE APPLICATION BY CONTACT WITH POLYESTER ROLLER

Abstract

In recent years, a new form of weed control has emerged, contact control. The aim of this study was to compare different modes of application and doses of the herbicide glyphosate in soy. The experiment was carried out in a commercial soybean area in Sinop MT. The experimental design was a randomized block, with five replications and eight treatments. The 8 treatments were: Physical control, manual weeding with a hoe; Application with costal sprayer in doses of 0.7 and 1.4 kg ha-1 of glyphosate; Bush, without weed control; Application with polyester roller in doses 0.7 and 1.4 kg ha-1 of glyphosate in contact with the soil; Application with polyester roller in doses 0.7 and 1.4 kg ha-1 of glyphosate at 2 cm from the ground. Weed population control and density, vegetative growth and soybean productivity were evaluated. The application via roller, both in contact with the soil, when only weed is shown to be as efficient as spraying in weed control. The species of Eleusine indica and Spermacoce latifolia were the species that maintained or even increased the density in the cultivation area. Regardless of the form of application, the use of glyphosate did not affect the vegetative growth and productivity of cultivar NS 7901 RR. Although no statistical differences were detected, productivity in general increased when glyphosate was applied, with no differences in the form of application, by contact or spray.