ABSTRACT.
Agronomic traits and chemical composition of forage sorghum plants fertilized with poultry litter and fermentative profile of silages

Nagnaldo T. Lucena1, Edson M. Santos1, Juliana S. Oliveira1, Alexandre F. Perazzo2, Gabriel F.L. Cruz1*, Danillo M. Pereira1, Gildênia A. Pereira1, Alberto J.S. Macêdo3, Rosângela C.S. Ramos4, and Messias S. Nogueira1
 
It is essential to determine the productive potential and quality of forage sorghum (Sorghum bicolor (L.) Moench) silages using alternative and organic inputs, such as poultry litter (PL), intending to higher efficiency, and sustainable development of animal production systems in the world. Poultry litter fertilization has been widely used in crops for silage production, where it is believed that fertilization with PL can influence the fermentation profile and composition of forage sorghum silages. The objective of this study was to evaluate different levels of fertilization with PL on the agronomic and quality characteristics of forage sorghum silage 'BRS Ponta Negra'. For determination of agronomic and productive characteristics, randomized blocks design was adopted, the treatments were different PL levels: 5, 10, and 15 Mg ha-1. While for the evaluation of silage characteristics, the design was completely randomized. With fertilizer doses, a linear increase was observed for plant height, stem diameter, leaf length, and consequently for fresh and DM productions. Linear reduction was observed for neutral detergent fiber, while crude protein and pH contents of silages increased linearly with PL levels. Quadratic effect occurred for gas and effluent losses. Poultry litter may be an alternative source to supply the N needs in the production of sorghum for silage under experimental similar conditions. Associating productivity with cultivation efficiency, the PL level 13.46 Mg ha-1 is recommended for presenting the highest N agronomic efficiency and good nutritional quality of the silage.
Keywords: Efficiency, forage conservation, nitrogen, organic fertilization, productivity.
1Universidade Federal da Paraíba, km 12, Rodovia PB-079, 58397-000, Areia, Brasil.*Corresponding author (g_ferreira_dm@hotmail.com).2Universidade Federal do Maranhão, km 04, Boa Vista s/n, 65500-000, Chapadinha, Brasil.3Universidade Federal de Viçosa, Av. Peter Henry Rolfs, 36570-900, Viçosa, Brasil.4Universidade Estadual do Sudoeste da Bahia, 7555, Av. Paralela, 45700-000, Itapetinga, Brasil.