The field trial was carried out over the period 2004-2006 at the experimental farm PD Kalná nad Hronom in south-western Slovakia. The aim of the research was to evaluate the conventional and reduced tillage. Three tillage practices on selected physical soil characteristics were evaluated. The sugar beet-spring barley-sunflower crop sequence was evaluated. The main plot with four replicates was 10 m by 550 m. The soil tillage treatments as follows: T1 conventional mould board ploughing with farm yard manure application to sugar beet and incorporation of post harvest residues of spring barley and sunflower; T2 conventional mould board ploughing; T3 no-till Horsch CONCORD CO 9. During June the soil samples were taken from 0.05-0.10m, 0.1-0.20m, 0.2-0.3m. The total porosity, soil bulk density and soil moisture was determined by core samples of 0,001m3. The differences between soil layer and crops growing in different years were ascertained. The SBD and total porosity was highly significantly influenced by weather condition and growing crops of evaluated years and SBD was also significantly influenced by tillage system. The soil bulk density under sugar beet and incorporation of farm yard manure influence the SBD (1,273 t m3) in 0.05-0.20 soil layer with comparison to 1.512 t m3 in mouldboard ploughing without organic manure application or 1.37 t m3 in no-till treatments. The SBD in deeper layer 0.20-0.30 ranged from 1.420 t m3 in no-till system to 1.528 t m3 in mouldboard ploughing and no significant differences has been noted. The spring barley and weather condition of 2005 create the same SBD in all tillage systems as follows: 1.389 t m3 (without organic manure) 1.400 t m3 (no till) – 1.473 t m3 (with organic manure). The year 2006 was characterised by wet condition. Canopy of sunflower with interaction of weather and tillage systems influenced the higher SBD in conventional plough without input of organic fertilizers 1.625 t m3. The SBD in no-till system was same than in conventional mouldboard ploughing with organic manure incorporation (1.465-1.456 m3). In three year average the conventional mould board ploughing with farm yard manure form the most suitable soil environment (SBD, total porosity and soil humidity retention) but we also recommended the no-till for this specific area of Slovak region.

conventional tillage; no-till; soil bulk density; total porosity; soil moisture; crop rotation

Presentation: oral