Productive and nutritional characteristics of Piatã-grass in integrated systems
SUMMARY This study aimed to evaluate the pasture productive and nutritional characteristics of Brachiaria brizantha cv. BRS Piatã in integrated systems with different densities of trees. Considering as plot the systems: integrated crop-livestock-forest with rows of trees (eucalyptus) spaced at 14 m and 357 trees ha-1 (ICLF-14m), ICLF with rows of trees spaced at 22 m and 227 trees ha-1 (ICLF-22m) and the integrated crop-livestock (ICL) with five remaining native trees ha-1; period of the year as subplots, and sampling points as subsubplots (A, B C, D, and E) arranged perpendicular to trees alleys. It was evaluated the production of forage and leaf blade dry mass, leaf:stem ratio, soil coverage, radiation photosynthetically active interception, canopy height, crude protein (CP), neutral detergent fiber (NDF), in vitro digestibility of organic matter (IVDOM) of the leaf blade, and stem associated with the leaf sheath. There was a significant difference (P<0.05) for all variables due to the month within the integrated systems. Mainly in January and March, showing the forage and leaf blade dry mass reduction due to a higher trees density. System with higher trees density showed the lowest soil coverage and canopy height sampling points A and E in ICLF-22m showed lower forage and leaf blade dry mass production and soil coverage. The system with higher trees density showed lower value of NDF of the leaf blade, and higher CP contents. The IVDOM of the leaf blade was higher in ICLF systems. For the evaluated parameters the best results were for the ICLF-22m.