Yield and quality responses of Megathyrsus maximus and Cynodon spp. forage grasses to irrigation

Abstract

Periodic variations in rainfall have resulted in longer periods of drought in traditional rainfed livestock systems on savanna areas in Brazil. However, irrigation management techniques and rotational grazing have improved the productivity of these systems by mitigating soil water stress on forage grasses. The objectives of this research were to evaluate the response of Megathyrsus maximus cv. Tanzania and Cyn-odon spp. cv. Tifton 85 (Cynodon nlemfuensis × Cynodon dactylon) forage grasses to irrigation, and to determine their irrigation water productivity (IWP). The experiment was conducted at the University of São Paulo in Brazil. Plant height (PH), dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were measured, and IWP was calculated. Tifton 85 had a higher CP content than Tanzania but a lower average DM yield. The irrigation management (IM) treat-ments did not influence CP levels of both forage grasses, but in most situations, did affect their average DM yield. The IWP of Tanzania and Tifton 85 forage grasses did not differ among irrigation management treatments.