Manejo e tratos culturais na produção de milho destinado a silagem

Abstract

Corn is one of the main products intended for animal feed, either as grain or forage, contributing directly to the milk and meat production chains. Several factors are responsible for increasing crop productivity, or even the quality of this food when destined for animals. The purpose of this research was study different management methods adopted in corn production destined for grains or silage for animal feed. Experiments were conducted at facilities of Nutrition and Bromatology Laboratory of the Federal University of Fronteira Sul (UFFS), Campus Erechim/RS. The experiments were conducted in a randomized block design, with four replications. Experiment one aimed to evaluate the selectivity and effectiveness of herbicides applied on the corn hybrid Agroceres AG 9025 PRO3 for weed control. In this experiment the treatments were used: glyphosate (1335 g ha-1), mesotrione (192 g ha-1), tembotrione (100.8 g ha-1), nicosulfuron (60 g ha-1), atrazine + simazine (1500 g ha-1), glyphosate + mesotrione (1440 + 192 g ha-1), glyphosate + tembotrione (1440 + 120 g ha-1), glyphosate + nicosulfuron (1440 + 60 g ha-1), glyphosate + atrazine + simazine (1440 + 1500 g ha-1), plus a weeded control. In the second experiment, the objective was to study the effect of nitrogen fertilization on the quality and productivity of the hybrid corn Dekalb DKB290. The treatments used were five doses of nitrogen applied in coverage, being: control without nitrogen, half of the dose (101.25 kg ha-1), the recommended dose (202.50 kg ha-1), one and a half times the dose (303.75 kg ha-1) and twice the dose (405.00 kg ha-1) of nitrogen, according to soil analysis. The applications of nitrogen in the form of urea were carried out in installments, in two stages of corn development, 40% in V3 and V4 (three to four leaves developed) and 60% in V6 and V7 (six to seven leaves). The last experiment aimed to compare groups of corn hybrids positioned for grain production and silage. The hybrids were tested for this: Pioneer P3016, Pioneer P4285, Syngenta 488, Syngenta Maximus, Forseed FS481, Forseed 2A620, Agroceres AG8061, Agroceres AG 8690, Brevant CD3612, Brevant 2A510, Limagrain LG 3055, Limagrain LG 36610, Dekal LGb6b10, Dekal LGb6 290, KWS K9606 and KWS KS9822, these being the most sown in the South for grain or silage production. For the first experiment, it is concluded that the association of glyphosate with other herbicides registered to the corn crop showed improvement in the control of weeds papuã and milhã. The addition of nitrogen doses in coverage provides increased water use efficiency, bromatological characteristics and corn grain yield found in the second experiment. It has not yet been possible to complete the third and last article of the dissertation so far, presenting the introduction, methodology and tabulated data of the dissertation.