With the objective to study the effect of total depth of water, nitrogen fertilization and their interaction on the growth factors, production, efficiency of use and forage quality as well as to determine production functions for total, foliar and stem dry matter of Tanzania grass (Panicum maximum cv. Tanzania) with the intention to obtain level of maximum and economic production of each analyzed production factor. The experiment was carried out in split-split-plot, where in the main plots the different irrigation levels were distributed (0, 30, 70,100 and 150% of field capacity (FC)), in the split plot the levels of nitrogen (0, 100, 275, 756 and 2079 kg N ha-1 year-1) and in the split-split plot the three climatic periods (summer, winter and spring). The higher irrigation regimes provided negative effects on the production of dry matter. The use of nitrogen levels above 756 kg N ha-1 year-1 did not show effect on the production of dry matter, the increments in the total and foliar production of dry matter for the levels of 100, 275, 756 and 1.769 kg N ha-1 year-1 were 15, 19, 29 and 20% (16% foliar), respectively.
irrigation levels; nitrogen fertilization; Panicum maximum; grass Tanzania; seasonal effect
