Crude protein, neutral detergent fiber and acid detergent fiber of forage grasses under irrigation and nitrogen in Parnaíba, Piaui

Abstract

With the main objective of evaluation the different levels of irrigation and nitrogen fertilization under the in the neutral detergent fiber contents (NDF), acid detergent fiber contents (ADN) and the of crude protein (PB) from the Brachiaria spp grass and Digitaria sp grass, it was conducted a experimental research in Embrapa Meio Norte, in Parnaíba, PI. The experimental design we in cased blocks, factorial outline 2 x 3 x 4, with three repetition; being two grasses, with three level of irrigation (80%, 50% e 20% from the evaporation Class A pan (ECA) and four levels of nitrogen (100; 250; 400 and 500 kg/ha/ano) the nitrogen fertilization was fractioned and applied, if form of covered urea, after the cut of each one in a period. The Digitaria showed higher level of FDN contents in relation to the Brachiaria spp in all level of nitrogen fertilization and level of irrigation applied. In relation to FDA contents the Digitaria was inferior to Brachiaria spp only in the intermediate level of irrigation and in the major level of nitrogen fertilization. The nitrogen fertilization affected positively the of crude protein contents from both grasses.