بررسي تاثير تقسيط نيتروژن و زمان مصرف آن بر روند تغييرات برخي از صفات كيفي چغندرقند

The effect of nitrogen split and the time of application on some quality characteristics in sugar beet production

With the objective of investigating the time of nitrogen(N) application and the beet combination of base vs. top dressing basal N/top dressing N application on some sugar beet characteristics this experiment was carried out in 1994, karaj - Iran. Experimental design was split plot within Randomize Complete Block with three replications. Four level of split N was applied (100% top dressing- 25% base, 75% top dressing - 50% base, 50%top dressing - 75% base - 25% top dressing) as the main plot and time of N application (planting time, 2-4 leaf stage, 8-10 leaf stage) as sub plots. Amount of N used in all the treatments was the same and equal to 138 kg/hectare. After 53 days from planting and receiving 824 degree days samples were taken and continued every 15 days intervals. The results showed that the time of N application influenced the amount of Na+ and a Amino - N. It was also shown that delay in time of N application increased the Na+ and a - Amino-N but did not effect amount of K+. The time of N - consumption affected on root impurities. S.C. was effected by N consumption in growth period. But, the results showed that there were no difference among N treatment with respect of sugar content.