Study of potassium and nitrogen fertilizer levels on the yield of sugar beet in jolge cultivar

To investigate the effect of fertilizers on calcareous soils of experimental field research was conducted in Meshkin-shahr to study the effects of different rates of nitrogen (143, 214 & 285 kg N ha-1) and potassium (0, 57 & 114 kg K2O ha-1) fertilization on yield, quality and nutrient contents of sugar beet grown on sandy calcareous soil. In this split plot design, the main plots were assigned to levels of N fertilizer and K levels were arranged to random as the sub-plots. The results showed that increasing N and K rates significantly increased root and foliage fresh and dry weight and sugar yield (ton ha-1) of sugar beet plants. Adding the highest level of K (114 kg K2O ha-1) under different rates of N significantly increased sucrose contents, recoverable sugar yield (ton ha-1) and some quality traits. Adding the highest level of N (285 kg N ha-1) under different rates of K significantly increased sugar loss (ton ha-1) and increased content and uptake of N and K in both root and foliage of sugar beet over two seasons. Increasing N level up to 285 kg N ha-1 (under 0.0 kg K2O ha-1) significantly increased impurities (Na, K & ?-amino-N) and sugar loss percentage. In crux, N fertilizer at a level of 285 kg N/fed accompanied with 114 kg K2O ha-1 were the most effective in improving yield, quality and nutritional status of sugar beet grown in a sandy calcareous soil.