Three-year investigations of eight different tillage treatments, combined with four mineral fertilizer rates, were carried out on luvic pseudogley in lower Podravina. The results referring to sugar beet are presented in this paper. The following ploughing treatments combined with four mineral fertilizer rates (low, medium, high and very high) were applied: ploughing at 20, 30, 40, 50 and 60 cm, ploughing at 20 cm with subsoiling at 50 and 70 cm, and ploughing at 30 cm with subsoiling at 50 cm. Residual effects of deep ploughing and mineral fertilization were followed up in the second and third trial years, hence both practices were uniform. As a rule, deep ploughing had a positive effect on the yield of sugar beet roots and sugar. Fertilization was generally inefficient in all three years, which particularly holds for higher rates. In accord with the individual effects of ploughing and fertilization, there was rather restricted interaction of these factors, with a more pronounced compensation effect of ploughing.

tillage; fertilizing; lessive pseudogley; sugar beet; yield

Published by University of Zagreb, Faculty of Agriculture, Zagreb, CROATIA
Sponsored by Ministry Science and Education of the Republic of Croatia