Produção e composição bromatológica do capim-piatã em diferentes frequências de corte sob irrigação

Abstract

The aim of this study was to evaluate the production, nutritional value and structural characteristics of pastures of Brachiaria brizantha cv. BRS Piatã subjected irrigation and to four cutting frequencies. The treatments were Piata cut grass at 21, 28, 35, and 42 days, submitted or not irrigation. The experimental design was completely randomized in a 4x2x3 factorial, four ages of the court, with and without irrigation, and three seasons (fall, winter and spring) and six repetitions of the area. Evaluation of crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin (LIG), in vitro digestibility of organic matter (IVOMD), leaf area index (LAI), Reason leaf area (LAR), specific leaf area (SLA), leaf weight ratio (RPF), height (ALT), total dry matter (TDM), leaf dry mass (MSF), stem dry weight (MSC) , dry mass of dead material (MSMM). The blade 100% water had a negative influence in the production of grass Piata, being very high for this cultivar. The spring was the most productive season, then the fall and winter, when it aims at greater production of leaf blade, the spring can be harvested at 21 days, 35 days to fall, and winter from 28 to 42 days, always giving priority the largest rest this season. Irrigation interfere with the structure of the grass sward Piata, increasing the percentage of leaf blade and improving the nutritional value of forage. For cutoff frequencies evaluated showed that the Piata grass can be used up to 35 days old without losing nutritional value. Autumn was the season that provides the best structural characteristics and nutritional value, results arising from this weather station.