Acúmulo de forragem em pastos de Megathyrsus maximus cv. Sempre-Verde submetidos a frequências de colheita

Abstract

The objective of this work was to evaluate the accumulation of forage on pastures of Megathyrsus maximus cv. always-green under frequency of sampling. Three treatments were evaluated, characterized by frequencies of harvest, and they include the fixed periods of 28 days, where 90% canopy intercept or 95% of the incident light, following a completely randomized design with four replicates of 4 m2 (2 m x 2 m) each. The experimental area was prepared by the conventional method (plowing and harrowing the ground) from March 2017. Prior to the establishment, in April 2017, simultaneously with the deployment, seedlings were removed from the green grass in an area next to the experimental area and transferred to the plots in the spacing of 0.5 x 0.5 m. We selected tussocks young and in a vegetative state. Thirty days after planting (end of May), a cut of standardization in all experimental plots, at approximately 30 cm of height from the ground. Successively the standardization, all the plots were managed according to the three defoliation conditions: 28 days, 90% and 95% of light interception (IL). All the times that the canopies reached their respective frequencies, two samples of forage were collected (squares of 0.5 x 0.5 m) per experimental unit. The samples were divided into two subsamples: one was used to estimate the forage mass (MF) and the other was separated into leaf blade (LF), stem preview (CV) and dead grass (FM) in order to estimate the percentage of these components in the forage mass. Through the sum of the masses of forage, subtracting the amount of dead forage, we calculated the forage accumulation (AF). The variables were subjected to analysis of variance, and the means between the treatments compared by Turkey’s test at 5% probability for error type I. There was no influence of frequencies in the accumulation of forage and forage accumulation rate. The use of variable frequency of harvesting is more effective in controlling the structure of the canopy of the fixes.

Keywords: Megathyrsus maximus cv. 2 Pasture forage. 3. Harvest.