Effect of the interaction between the method of magnesium application and amount of nitrogen fertilizer application on sugar recovery and technical quality of sugarbeet (Beta vulgaris L.)

The study discusses the quantitative (beet yield, recoverable sugar yield) and qualitative (sugar content, melassigenic nonsugars) response of sugarbeet to interactions between the method of magnesium application – into the soil (in the form of kieserite) or foliar application (in the form of epsomite) – and increasing nitrogen fertilization (0, 60, 120, 180 and 240 kg/ha N). The beet yields obtained increased significantly up to an application of 180 kg/ha N. Magnesium fertilizer did not exert a significant impact on beet yields. The technological quality parameters of beet with respect to sugar, a-amino-N and recoverable sugar contents depended significantly on the amount of nitrogen fertilizer. Recoverable sugar yield in t/ha was significantly influenced by the interaction between the soil-applied magnesium (kieserite) and amount of nitrogen. Plants, which were not treated with magnesium produced the highest sugar yield at a rate of 180 kg/ha N, while those treated with Mg already yielded the same amount of sugar at a rate of 60 kg/ha N.