EFFECT OF NITROGEN FERTILIZATION AND UNDERSOWING ON YIELD AND QUALITY OF CYNOSURETUM CRISTATI-TYPE MEADOWS IN HILLY-MOUNTAINOUS GRASSLANDS IN SERBIA

The trial was carried out during two years (2003 and 2004) on Cynosuretum cristati-type meadow in the hillymountainous region of Serbia (altitude 1158 m). The investigation included five nitrogen fertilizer rates (0, 40, 80, 120 and 160 kg ha-1 yr-1) and undersowing with red clover and birdsfoot trefoil. Increase in nitrogen fertilization level resulted in corresponding increases in the quantity and quality of grass, while legumes and other herbages decreased. Maximum two-year average dry matter yield of 4.44 t ha-1 was achieved with the highest N rate (160 kg ha-1). The increase was 2.03 t ha-1 or 85.0% compared with the control. Increased N rates increasing the contents of protein, ash, fat, Cu, Co, and NO3, and reduced the contents of cellulose, K, P, Ca, Mg, S, Zn, and B. Dry matter yield in the undersowing treatment was low, only slightly over that of the control in both study years. Furthermore, undersowing failed to affect the chemical and mineral composition of dry matter