Herbage accumulation, morphological composition, and nutritive value of Paspalum notatum CV. INIA Sepé

Abstract

Defoliation strategies determine sward canopy structure and affect forage accumulation and nutritive value. The objective of this study was to determine forage accumulation, morphological composition and nutritive value of inia Sepé subjected to combinations of three frequencies (defoliation at 90%, 95% and maximum canopy light interception during regrowth —li90%, li95% and liMax), and two severities of defoliation (40 and 60% of the pre-cutting height). The experiment was carried out from November 15th, 2018 to March 31st, 2019 in Tacuarembó. Measurements of li and canopy height, forage mass morphological composition and nutritional value were carried out. Forage mass was greater in Feb-March. The percentage of leaves was greater for the higher defoliation frequency treatment (li90%). The percentage of stems did not vary among treatments (average of 23%). The percentage of dead material was greater for the lower defoliation frequency treatment (liMax) and 40% defoliation severity. Greater adf and ndf values and smaller digestibility were recorded for liMax/40% combination. For li90%, greater adf and ndf, and smaller digestibility were recorded for the 60% defoliation severity (Feb-March). Forage accumulation was greater for li90% and li95%. inia Sepé shows large flexibility to defoliation management, and the optimal pre-cutting target should not exceed li95% (i.e. 30 cm of canopy height) in order to ensure production of high nutritive value forage and harvest efficiency.

Keywords

• herbage accumulation
• paspalum notatum
• nutritional value