Bromatological characteristics of Macrotyloma axillare as a function of combined supply of phosphorus and calcium ; Características bromatológicas de Macrotyloma axillare em função do suprimento combinado de fósforo e cálcio

The supply of nutrients to forage legumes is significant for their nutritional quality. The study aimed to evaluate the bromatological characteristics of the legume Macrotyloma axillare in response to the combined application of phosphorus and calcium. The study was conducted in a greenhouse on a Red Yellow Ultisol. A fractionated 52 factorial was used, with 13 different combinations of phosphorus and calcium application rates (P-Ca): 0-0; 0-20; 0-40; 100-10; 100-30; 200-0; 200-20; 200-40; 300-10; 300-30; 400-0; 400-20; and 400-40 mg dm-3. Experimental units were set in a randomized block design, with four replications. Neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose, cellulose, lignin, and crude protein (CP) in the leaves and branches were determined in two harvests. In both harvests of the legume we observed that the ADF, hemicellulose, cellulose, and lignin contents in the leaves did not show isolated or combined responses to phosphorus and calcium rates. It was concluded that the combined supply of phosphorus and calcium did not interfere in the nutritional quality of the legume. Calcium supplied alone interfered only the NDF content and phosphorus supplied of the CP of the leaves. Phosphorus rates of 31.5 mg dm-3 and 28.2 mg dm-3 were responsible for the lower NDF content in the leaves and the higher hemicellulose content in the branches, respectively. ; O fornecimento de nutrientes para as leguminosas forrageiras é importante para sua qualidade nutricional. O estudo objetivou avaliar as características bromatológicas da Macrotyloma axillare em resposta a aplicaçãocombinada de doses de fósforo e cálcio. O estudo foi desenvolvido em uma casa de vegetação sob um Argissolo Vermelho-Amarelo. Utilizou-se um esquema fatorial 52 fracionado, com 13 combinações diferentes das doses de fósforo e cálcio (P-Ca): 0-0, 0‒40, 0‒80, 15‒20, 15‒60, 30‒0, 30‒40, 30‒80, 45‒20, 45‒60, 60‒0, 60‒40, e 60‒80 mg dm-3. As unidades experimentais foram distribuídas em delineamento de blocos ao acaso, com ...