Influence of fertilization and nitrate-nitrogen position in soil profile on the sugar beet root yield and quality

Researches, which have lasted for two years, were carried out on long-term trial field at Rimski Sancevi, Novi Sad, Serbia. In this trial, the eight fertilization variants of N, P2O5 and K2O increased amounts were studied. Sugar beet root and tops yields were determined, as well as the elements of technological sugar beet root quality. Based on these results, percentage of sugar utilization and refined sugar yield was defined. In the spring, before applying of N fertilizer, amount of nitrate nitrogen in the soil and its influence on yield and quality was determined. The highest root yield in 2002 was produced at the variant N100 P150 K150, and in 2003 at the variant N150 P150 K150. However, in both years, referring to the variant N100 P100 K100, the differences were not statistically significant. Increasing of nitrogen amounts had negative effects on refined sugar yield. Amounts of NO3-N in the soil in spring, before sugar beet sowing, in 2002 had significant influence on root yield and refined sugar yield. In the year 2003, which was highly dry, high correlation ratio were gained between amounts of NO3-N in the soil and root quality parameters, but it wasn't significant between nitrogen amounts and root and refined sugar yield.