Composição bromatológica e produtividade do capim-andropógon em diferentes idades de rebrota em sistema silvipastoril

Abstract

The study evaluated composition and productivity of Andropogon grass at different ages of resprout, associated with the species Tabebuia serratifolia and Hymenaea courbaril, during the rainy period, in Teresina, Piauí. A random blocks design was adopted, in a 3 x 2 factorial scheme, with subdivided parcels, being the parcels the environments (shading with Tabebuia serratifolia, Hymenaea courbaril and open area) and position (rising and setting), and subparcels the ages (35, 49 and 63 days), with five repetitions. There was interaction between the environment and age for DM in the plant, NDF and ADF in the plant and leaves, and NDIN in leaves. The CP in leaves in the shade was higher (9.65 ± 0.94%) compared to the open area (9.16 ± 1.41%). There was a linear effect (p < 0.01) of the age on CP in the plant and leaves. From days 47.7 and 48.8 there was a reduction in the leaf/steam ratio of Andropogon grass under T. serratifolia and H. courbaril, respectively. The culture of the grass in silvopastoral systems is viable, due to the stability in the composition of DM and ADF in the ratios of NDIN and ADIN in the plant and leaves, as well as for CP in plant and NDF in leaves, with higher CP levels in leaves of the grass. There was no difference in the levels of NDF in the grass in function of the age among environments.