Eficácia de herbicidas aplicados isolados em pré e pós-emergência no controle de mucuna-preta

Abstract

In order to evaluate the efficacy of herbicides solos to control velvetbean were conducted four trials. In pre-emergence were used the herbicides: amicarbazone (1225 g ha^-1); tebuthiuron (900 g ha^-1) and sulfentrazone (600 g ha^-1) and in post-emergence were used the three herbicides previously cited and 2,4 D amine (670 g ha^-1) ; atrazine (3250 g ha^-1); Carfentrazone-ethyl (35 g ha^-1) and mesotrione (132 g ha^-1) applied solo in three different stage of development: Trial 1: Two leaves unfolded (BBCH - 12); Trial 2: Seven lateral gems visible (BBCH - 27) and trial 3: 50% of the maximum length reached (BBCH - 35). The design was a randomized complete block with four repetitions per treatment. The measured variable (efficacy) was subjected to analysis of variance by F test, and averages were compared by Tukey test at 5% probability. In pre-emergence was observed that amicarbazone and tebuthiuron, provided 100% of control. In post-emergence, amicarbazone provided 100% of control for all stage of development; the same result was observed in the treatment with sulfentrazone and atrazine in plants with two leaves unfolded (BBCH - 12) and in the treatment with atrazine and tebuthiuron in plants with seven lateral buds visible (BBCH - 27).