Optimizing the Use of Mineral and Organic Nitrogen Fertilizers for Barley Crops on Reddish Preluvosoil at Moara Domnesca

The purpose of this paper is to present the research conducted in the agricultural year of 2014-2015, situated on the experimental field of the Department of Soil Sciences, at Moara Domneasca, on red soil. The barley crop is part of a crop rotation wheat-barley-sugar beet. The experience is a two-factor concept, organised in three repetitions, with the next factors: a – organic fertilization and b – mineral fertilization. As natural fertilizers, were used plant residues and manure, nourishment needs were supplemented with mineral fertilizer, based mostly on nitrogen. In addition to the nitrogen, for all three crops was applied at a dose of P70. Regardless of any organic fertilizer, the application of mineral nitrogen is useful until a certain point, anything more than that is not fruitful, and does not assure great results in output. In the research were determined and interpreted the following indicators: production of barley, the number of ears/sq m, hectolitre mass and thousand grain mass. The experimental data obtained were calculated and interpreted by analysis of variance. The research has shown that nitrogen fertilization with organic and mineral nitrogen increases barley production. The best barley production was obtained within b4-N140 variant, combined with organic fertilizer variant a2 – residue of 30 t/ha manure, of 75.6 q/ha.