Influence of nitrogen fertilization on spring barley yield, and on soil and water chemical properties

Key issues of today’s and future agricultural production are soil and water rational management and protection. Surplus of applied nutrients that plants do not absorb is a potential source of emissions from the soil into the water. This paper presents the results of a field experiment that was conducted at the faculty experimental field in Rodoc near Mostar during 2008. The experiment was set up by randomized block layout and it was consisted of five variants with four repetitions. Variants used in the experiment were: 1. Control, 2. N50PK, 3. N100PK, 4. N150PK and 5. N200PK. Fertilization of spring barley was performed prior to seeding with a 7:20:30 NPK formulation and with different amounts of KAN on the variants 4 and 5. The first feeding was conducted during barley tillering stage and the next one a month later. Statistical processing of research results revealed that there were significant effects of fertilizer variants on barley yield, plant density, straw length, ear length, number of florets in the ear, number of grains in the ear and nitrogen content in grain. For the 1000-grain weight, carbon content (% in dry matter), sulfur content (% in dry matter), hydrogen content (% in dry matter) and water content in grain (% moisture) significant effects of fertilizer variants were not detected. In the soil there was no significant effect of fertilization according to individual variants. Mean values of certain ions concentration in rinse waters in June there were significant differences respectively in the content of nitrate, nitrite and sulphate, while for the other analyzed parameters statistically significant differences were not determined. Due to comparison and relevance of the research, experiment is continuing in 2009 with the same variations and repetitions.