Seletividade de diferentes herbicidas em espécies forrageiras

Abstract

Currently, Brazilian livestock stands out economically, having the largest commercial herd in the world, it is estimated that 90% of the meat produced in Brazil comes from the pasture production system. The presence of weeds decreases the quality of the pasture, as they compete for water and nutrients. The most used control method and also considered the most effective is chemical control. Herbicides are able to eliminate or suppress the growth of specific species, but improper use can cause crop intoxication. New technologies need to be employed so that we can achieve high productivity and, at the same time, that are less harmful to environmental, animal and human health. The objective of this work is to evaluate possible phytotoxic effects caused by the use of herbicide with XT technology, compared with other conventional products in grasses. The experiment was implemented in the experimental farm of the Federal Technological University of Paraná ­ Campus Dois Vizinhos. Possible phytotoxic effects were evaluated in two cultures: Brachiaria decumbens and Panicum maximum, with the application of herbicides (Planador XT®, Quallis® and 2­4,D Amina®). The application was carried out 30 days after emergence. The experimental design used was completely randomized, with four replications. During the experiment, evaluations of phytotoxicity, plant height and mean tiller count were carried out. At the end of the work, the evaluations were: green matter weight and shoot dry matter weight. After obtaining the data, they were submitted to analysis of variance, and the averages submitted to the Tukey test (5%). Planador XT® was more aggressive for the species in question, leading to a significant loss in dry matter production. 2,4­D Amina® and Quallis® did not show significant loss compared to the control.