TILLAGE SYSTEMS OF WINTER OILSEED RAPE (BRASSICA NAPUS L.) PRODUCTION WITH RESPECT TO COSTS, ENERGY AND LABOUR CONSUMPTION

The objective of this work is to assess different systems of winter oilseed rape production, i.e. reduced (RT) and conventional (CT) tillage, mainly in terms of yields, fuel and labour consumption, machinery and material costs in the conditions of the Czech Republic. Since 2001/02, trials were accomplished in 548 fields. Over the first five years, CT yields generally surpassed RT yields. But gradually, this trend turned over. The potatoes production area proved to be the most favourable in terms of yields. Recently namely, beet production area demonstrated also good results. When excluding cases with organic fertilizer application, the average fuel consumption of RT was by 15.7 % lower than that of the CT, the overall labour consumption again lower by 18.4 %, and finally the machinery costs lower by 10.8 %. All the above mentioned differences proved statistically significant. Concerning earnings per hectare, RT results proved superior to CT in all of the production areas.