Impact of nitrogen fertilizers on forage accumulation and protein and fiber fractions of Urochloa Brizantha cv Marandu

• Grant number: 19/24965-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2020
• End date: July 31, 2021
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Pastures and Forage Crops
• Principal Investigator: Ana Cláudia Ruggieri
• Grantee: Gabriely Veiga da Silva
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Associated research grant: 15/16631-5 - Management strategies to reduce environmental impacts of beef cattle production systems, AP.PFPMCG.TEM

Abstract

In the intensification of pasture management, forage production is of central importance, and nitrogen fertilization represents an alternative to minimize low herbage accumulation and improve forage chemical composition. Our objective is to investigate the effects of different nitrogen sources and doses on the productive and chemical characteristics of forage grass pastures Urochloa brizantha cv marandu. The experimental design will be randomized blocks (DBC) with 4 replications. The experiment will be carried out in plots plots of 12 m2 managed at 30/15 cm height. The treatments will be: three sources of N (urea, ammonium sulfate and ammonium nitrate), three doses of N (90, 180 and 270 kg ha-1 year-1) and a control treatment (without fertilization). Will be evaluated at herbage accumulation (HA), and dry matter content (DM), morphological composition of forage, organic matter (MO), mineral material (MM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) ), lignin (Lig), and protein fractions (A, B1 + B2, B3 and C). The ANOVA will be performed by Tukey test at 5% and the effect of orthogonal polynomial contrast doses. Nitrogen fertilization is expected to increase herbage accumulation and change its chemical composition, increasing protein content and decreasing fibrous fractions in dry matter. (AU)