INFLUENCE OF ORGANIC AND MINERAL FERTILIZATION ON GRASSLAND OF Dichanthium ischaemum L. ROBERTY IN THE MOLDAVIAN STEPPE

Given that in Moldavia and on meadows in Tutova Depression have been little research on grasslands of Dichanthium ischaemum L. Roberty (old world bluestem), we started at the RDCSEC Perieni, Vaslui, an experience on the effect of organic and mineral fertilization on yield and quality of forage obtained. It was administered organic fertilizer (well fermented sheep manure) in the fall of 2012, at 10 t ha-1 yr-1 and 30t ha-1 yr-1, and at the beginning of the growing season (April, 2013) were administered N50P25 kg ha-1 yr-1, respectively N75P25 kg ha-1 yr-1. In this paper we show preliminary values in 2013 as part of a medium-term experience (2013-2015). Harvesting took place in earing dominant species. The results showed various possibilities of increasing production grasslands of old world bluestem. In the variants fertilized with sheep manure yields ranged from 1.7 to 2.5 t ha-1 DM and 180-215 kg ha-1 CP, while the variants ranged from mineral fertilizers production 1.2-1.9 ha-1 DM and 160-190 kg ha-1 CP, and in embodiments with fertilizer production ranged from 0.6 t ha-1 DM to 1.05 t ha-1 DM. The results of the harvesting period bring valuable information on the optimal harvest time. Thus, the variants where harvesting was performed at earing of old world bluestem, yields were close in value of options where harvesting took place at the beginning of flowering. Results not recommend harvesting at full flowering or seed maturity, yields are significantly lower. Crude protein (CP) content decreases with vegetation. The highest content of crude protein was recorded in variants fertilized with sheep manure (30 t ha-1 yr-1) and harvested at early flowering earing dominant species. Regarding the content of Ca and P, and the ratio of these preliminary results strengthen the hypothesis that lead to optimal harvest must occur at earing species Dichanthium ischaemum L. Roberty to get the highest yield and better quality.