Nitrogen (N) is considered one of the major nutrients responsible for vegetative pasture growth, by influencing forage productivity and nutritive value. With this in mind, dry mass production and quality of Brachiaria brizantha (A. Rich) Stapf cultivars were studied and evaluated in order to discover nitrogen (N) fertilization effect on pasture grown under Brazilian savanna conditions. The experimental design used was randomized block in a 3 x 4 factorial scheme (three Brachiaria brizantha cultivars: Marandu, Xaraés, and MG-4 and applying four doses of N: 0, 50, 100, and 150 mg.dm-3, using urea as N source with three replications. Three forage cuttings were done in 30 day intervals. Nitrogen fertilization resulted in a linear increase of dry mass production, crude protein content, nitrate, ammonium, and chlorophyll (SPAD unit) content and a decrease of neutral detergent fiber (NDF) and acid detergent fiber (ADF) content in Brachiaria brizantha cultivars. Xaraés cultivar presented greater dry mass production, crude protein content, chlorophyll (SPAD unit) content, and lower NDF and ADF content than Marandu and MG-4 cultivars.
Bromatologic composition; Marandu; MG-4; SPAD; Xaraés; Brachiaria brizantha
