Potencial produtivo e composição bromatológica de híbridos de sorgo forrageiro submetido à adubação nitrogenada

Abstract

An experiment was conducted to evaluate the forage potential and chemical composition of hybrids of Sudan (Sorghum sudanense L.) and sorghum grass Sorghum bicolor (L.) Moench on nitrogen fertilization in a cutting regime. The treatments consisted of four hybrids: 0371008, 0371014, 0371020 and BR 800 and three nitrogen doses (0, 60 and 120 kg/ha). The randomized complete block design was used in 4 x 3 factorial, with four repetitions. The total dry matter production (TDMP), the dry matter production (DMP), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and lignin (LIG) were analysed. There wasn´t significant (P>0.05) of TDMP between hybrids and N doses. The DMP differed (P<0.05) between hybrids and N doses, in the first and fourth cutting height. The CO showed interaction between hybrids and N doses evaluated (P<0.05) in all cuts, except the BR 800 in the first cut. There was interaction (P<0.05) between the NDF and ADF. The values of LIG showed interaction (P<0.05) of the hybrids 0371008 and 0371020 and N doses applied at the first cutting heights. There were differences significant (P<0.05) in second cutting heights for the hybrids 0371014 and 0371020, in N doses, while the fourth cutting heights the N doses influenced the levels of LIG (P<0.05) compared to hybrids.