Influência de fungicidas na integridade de colmo e produtividade na cultura do milho

Abstract

Regarding corn crop, to acquire higher yields, it is essential to preserve the plant structure, such as leaves and thatch. The goal of this study was to evaluate the efficacy of fungicides of the carboxamide and other groups in the maintenance of the thatch integrity and in the yield increase of corn crop. The experiment was in Uberlândia (MG), during the second season of 2016. A randomized-complete block was designed with seven treatments, with a control and other six treatments with different chemical compounds (triazole, strobilurin, dithiocarbamate and carboxamide). It was evaluate the crop height, height of corncob insertion, green leaf area, thatch density (moist and dry), quantity of lignin and cellulose in thatch, thatch breaking strength, thatch breaking height and grain yield. Under the conditions that this test was conducted, no differences were observed between heights of plants and corncob, but all treatments with fungicides, when compared to the control, provided higher grain yield, thatch strength at break and wet and dry thatch density. When comparing the different treatments with fungicides, it was observed that the treatments with carboxamide were provided by corn plants greater grain yield, thatch dry matter and chemical components (cellulose and lignin) that confer resistance to that thatch, consequently plants with thatch more resistant to breaking besides higher density of moist and dry thatch.