Aimed at determining the optimal ploughing depth and making tillage simpler and less costly, taking into account edaphic and climatic conditions as well as biological and agrotechnical requirements of crops grown, longterm investigations of the optimal depth of basic tillage are carried out on Stagnic Luvisols of sloping terrains in central Croatia. This paper presents the results relating to the yields of maize grain. Yields achieved by the studied tillage treatments point to the conclusion that the no-tillage variant on the soil type under study (Stagnic Luvisols) cannot match the classical, standard soil tillage. Conventional tillage to different depths in any direction is still a safe warranty for high yields on this soil type. In the first trial year, the highest yield of 9.60 t ha-1 was obtained with ploughing up/down the slope. In precipitation deficient years, treatments with deeper ploughing are more efficient. Thus, in the second trial year, the highest yield of 7.97 t ha-1 was achieved in the variant involving very deep ploughing. With respect to the topical trend of applying any of the reduced tillage treatments in our agriculture, and considering the complexity of this problem, namely, application of a new soil tillage technology, further detailed, longterm and complex multidisciplinary research work is necessary, which should include researchers from all fields relating to these problems.

tillage; stagnic luvisol; yield; maize

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