EFEITO DO MANEJO SOB OFERTAS DE FORRAGEM NA ATIVIDADE DA CELULASE EM PASTOS DE CAPIM-XARAÉS

The objective was to evaluate the cellulase enzymatic activity of dystrophic Red Latosol soil under Xaraes grass grasses managed at different levels of forage allowance (4, 7, 10 and 13 DM kg 100 kg-1 PC) and rotational stocking. Soil samples were taken in the rainy season, every 21 days, before each grazing cycle and in June, at a pre-defined date, since there was no grazing at that time. Thus, soil collection dates were described as evaluation days and not as grazing: 1 (January), 21 (early February), 42 (late February) and 150 (June 2008). The experimental design was completely randomized, with three replications per forage allowance. The analysis of variance and Tukey's test were performed at a 5% probability level. In all forage allowances, the highest (P<0,05) activity of the enzyme was observed on evaluation day 150, which occurred in the dry season, when no grazing occurred, providing more material to the microorganisms. The forage allowances modified the cellulase activity, but without a behavior pattern. The amount of substrate available for soil microorganisms influences the enzymatic activity of cellulose.