Effect of 2.4-D addition to glyphosate for difficult control weeds species

Abstract

The 2,4-D has been one of the most widely used herbicide in combination with glyphosate, especially in applications desiccation pre-planting. The objective of this study was to evaluate the effect of adding 2,4-D to glyphosate for the control of weed species considered difficult to control (Commelina benghalensis, Richardia brasiliensis, Euphorbia heterophylla, Spermacoce latifolia, Ipomoea grandifolia e Conyza spp.). The experimental design was completely randomized, and treatments were arranged in a 3 x 4 factorial design with four replications. The first factor was composed of stages of development of weeds (2-4, 4-6 e >10 leaves) and the second factor by treatment with glyphosate (720 g i.a. ha^-1), 2,4-D (670 g i.a. ha^-1) glyphosate+2,4-D (720+670 g i.a. ha^-1) and a treatment without herbicide (control). For Conyza spp. in green house, were performed three additional herbicide treatments varying doses of glyphosate and 2,4-D. The addition of 2,4-D to glyphosate is crucial to accelerate and improve weed control considered unwieldy as those studied in this work.