Effects of organic and mineral fertilization on NPK status in soil and plant, and yield of red beet (Beta vulgarisvar.conditiva)

Abstract

Two-year field fertilization trial with red beet (Beta vulgaris var. conditiva) was carried out at two locations in Croatia. The trial was set up according to the Latin square method with four fertilization treatments (5 kg m-2 stable manure, 50 and 100 g m-2 NPK 5-20-30 and unfertilized control). In most cases the highest soil P and K content was obtained in the treatment with stable manure or 100 g m-2 NPK 5-20-30. A similar situation as in the soil was also obtained in plants. The highest N, P, K contents in 2003, and also P and K in 2004 in red beet were determined in the treatment with stable manure. Comparison of yields per fertilization treatment shows that the control treatment gave the lowest yield in both years. The highest yield in 2003 was determined in the treatment with stable manure (0.99 kg m-2) and there was no significant difference in comparison with the 100 g m-2 NPK treatment (0.82 kg m-2). Although there were no significant differences in 2004 between fertilization treatments, the relatively highest yield (4.59 kg m-2) was determined in the treatment with 100 g m-2 NPK. Such wide variations are probably a consequence of weather conditions.