Agronomic characteristics and nutritional value of oats and corn intercropped with Brachiaria in a crop-livestock integration system

Abstract

The objective was to evaluate the dry matter production for oat grazing, the nutritional value of oats and corn, and the amount of oatmeal and brachiaria biomass for direct seeding. The experimental design was in randomized blocks with four replicates. The oat treatments were without grazing and one grazing (both with two applications of N of 60 kg ha^-1) and two grazing (three applications of N of 40 kg ha^-1). The grazing was carried out up to the height of 15 cm from the soil. After 131 days of oats sowing (DS) the corn was sown, and the brachiaria (Urochloa ruziziensis) was sown between the lines of maize. Up to the first grazing there were no differences in nutritional value and oat characteristics. At 98 DS (before the second grazing), oats with cover fertilization (80 or 120 kg ha^-1 of N) had higher height, stalk diameter, dry matter yield per hectare (DMY) and protein content. The highest DMY occurred in oats without grazing (3667 kg ha^-1) and the highest protein content in grazed oats and with 120 kg ha^-1 of N in cover. Nitrogen fertilization in oats under grazing produces forage of whole plant corn in succession with higher protein content. The sum of DMY from oats and brachiara allows the use of maize for whole plant silage and no-tillage with sustainable vegetation cover (above 6 tons year^-1), except when the oats were grazed twice and without nitrogen fertilization in cover.

Keywords: Agrosystems, forage quality, nitrogen fertilization, no-till.