Uso de extrato pirolenhoso com glifosato para o controle de Megathyrsus maximus

Abstract

Glyphosate [N-(phosphonomethyl)glycine] has a wide range of uses, however, despite the effectiveness of its molecule, there is a major harmful factor to the ecosystem caused by its incorrect use. Therefore, the objective of this work was to evaluate the reduction of glyphosate doses using different concentrations of pyroligneous extract as an adjuvant in the post-emergence control of crabgrass. For this purpose, 1 test was carried out in a greenhouse at CECA/UFAL, in a completely randomized design and 5x2 factorial statistical arrangement, consisting of 5 doses of glyphosate, with oil condition and without mineral oil (0.5% V/ V), which was used as an adjuvant, with 4 replications each treatment, totaling 40 plots. The commercial dose was used as a base (3.5 L/ha), where every 0.5 liter of reduced glyphosate was added the same amount of pyroligneous extract (EP), from the trade mark SDM® (3.5 L, 3 L +0.5 L EP, 2.5 L +1 L EP, 1.5 L+2 L EP and control). The following variables evaluated were: damage scale, relative dry mass, number of regrowth and relative dry mass of regrowth. Therefore, the combination of glyphosate with pyroligneous extract is an option for controlling M. maximus and mitigating damage to the environment. The combination containing the lowest dose of glyphosate, added to the highest dose of pyroligneous extract (1.5 L glyphosate + 2.0 L pyroligneous extract), in the presence of mineral oil, was the most efficient in reducing the percentage of dry mass of M. maximus.

Key words: Bioinputs; environmental benefits; pyroligneous liquid.