Mineral nitrogen effect applied to the lucerne crop and the factor which co-operates to his recover

Utility of lucerne crops fertilization with nitrogen fertilizer is a problem much discussed and frequently contradictory. In this paper are presented the increases in dry substances and crude protein which are achieved for 1 kg nitrogen applied to a lucerne crop, important indicators relating to fertilizer opportunity of this crop with mineral nitrogen. Determination of nitrogen recover coefficient from plant biomass yield represents, also, one estimate mean of utilization indicative of chemical fertilizers with nitrogen by the plants and to estimate quantitative balance of this element in agro-ecosystem represented by a lucerne crop.