Soil tillage needs a radical change for sustainability

In Central Europe, the challenge in soil tillage throughout the last century can be characterized as a fi ght against extreme climatic and economic situations. From 1800s till the 1970s, the main requirement of soil tillage was to provide suitable soil conditions for plant growth (moreover with fi ne structure). Both climatic and economic diffi culties were benefi cial in establishing new tillage trends, however overestimation of the crop demands have presumably been promoted by the deterioration in soil quality. From the end of the 1990s, new requirements have also been introduced because of the rise in energy prices and because of the need to cut production costs. Th e reduced tillage in Central European region showed some advantages, e.g. less soil disturbance and traffi c however, that resulted in new soil condition defects (e.g. top- and subsoil compaction, structure degradation). Th e ideas of sustainability off ered a better solution that is to conserve soil resources and to protect the environment. A new problem, the global climate change, and the importance of the adaptability fasten to the original sustainable goals. In this paper the features of soil quality deteriorating tillage (conventional, over-reduced) are summarised, the steps of improvement are demonstrated, and factors aff ecting sustainable soil tillage are formulated

Effects of wheat cover crop desiccation times on soil physical properties and early growth of corn under no -till and conventional tillage systems

Cover crops can improve soil physical properties but can present challenges for subsequent cash crop growth. The objectives of this research were to investigate the influence of a winter wheat (Triticum aestivum) cover crop on selected soil physical properties and early development of corn in a corn (Zea mays)-soybean (Glycine max) crop rotation. The measurements were conducted on two Indiana research farms, both with dominant silt loam soil types during seasons 2000, 2001 and 2002. The experimental design was a split-split plot, with tillage treatment as the main effect (spring disking conventional till (CT) and no-till (NT)), two cash crops as the first split (soybean (B) and corn (C)), and three cover crop treatments as the second split (no cover crop (N), early (E) and regular (R) cover crop desiccation). Soil aggregation was usually increased by either E or R relative to N cover crop, and more consistently so in CT than NT. Both the R and E treatments tended to decrease bulk density, cone resistance and soil temperature, but increase total porosity, air-filled porosity, water retention and vane shear strength in both tillage systems, whereas K sat tended to improve with E or R cover treatments only in CT. Steady-state infiltration, measured on N and R only, tended to improve with R in both tillage systems. For both tillage treatments, both E and R increased soil water content, when compared with N, except in the case of early spring drought, when R transpired more water than E and was similar in water content to N. In years without early spring drought, early corn shoot and root growth following E in CT was either greater or not different than the other two treatments, whereas in NT the R \u3e E \u3e N pattern was frequently observed. In case of early spring drought, the E treatment on both tillage systems had better corn growth than both R and N treatments. The results suggest that despite generally comparable soil structure improvements by both E and R treatments in both tillage systems, early desiccation is the more desirable treatment prior to corn production due to better soil water conservation in droughty weather

Effects of conventional and reduced tillage systems in winter wheat — soybean crop rotation on crops biomass development

Croatian Baranja region contains soils with highly quality crop production properties, but the knowledge of the effects of reduced tillage systems is lacking. Our investigations were conducted under field conditions at Knezevo site chernozem in four replications. They included four soil tillage systems (CT: conventional tillage, with ploughing up to the 30 cm as a primary tillage; DS: diskharrowing up to the 15 cm; CH: chiselling up to the 30 cm + diskharrowing; NT: no-till seed drilling), both for winter wheat ( Triticum aestivum L. )-soybean ( Glycine max L. ) in crop rotation during three growing seasons (2002–2004). All measured crop properties were strongly affected by different seasons, especially with the season of 2003 with extreme drought. Crop biomass in five growth stages for winter wheat showed that at the beginning DS and CH had stronger growth than CT and NT, but differences vanished toward final stages. Winter wheat grain yield achieved by reduced tillage systems was in average either higher (CH=5.59 t ha −1 ) or not different (5.38 and 5.23 t ha −1 for DS and NT, respectively) than CT (5.28 t ha −1 ). Soybean growth was consistently the most impaired at NT system, especially at the full maturity stage, where also DS and CH had lower biomass than CT. Soybean grain yield confirmed biomass results, since NT (2.11 t ha −1 ) had always the lowest yield, when compared with other tillage systems (CT=2.88, CH=2.77 and DS=2.72 t ha −1 ). Our conclusion is that within the Croatian Baranja environmental conditions is possible to replace soil tillage based on the ploughing for winter wheat and soybean with reduced soil tillage systems based on disking and chiselling, whereas no-till system still needs solution which will address drought-related problems

Soil tillage impacts on nutritional status of soybean

Soybean were grown under field conditions on chernozem soil for four growing seasons (from 2002 to 2005). Three treatment of soil tillage were applied as follows: a) conventional tillage, b) reduced tillage (diskharrowing instead of ploughing) and c) no-till (zero-tillage). In general, the characteristics of growing season (the factor „year“) were more influencing factor of soybean nutritional status (aerial part in stage of full-developed pods) in comparison with the soil tillage. In our study, low influences of applied soil tillage treatments on nutritional status of soybean were found because significant differences on soybean composition were found only for four (Cu, Cr, Sr and Ba) from total 20 analysed elements. For example, conventional tillage resulted by the higher plant Cu (by 15% and 18% in comparison with DH and NT, respectively), and the lower plant Sr (by 12% and 16%, respectively) and Ba (by 26% and 23%, respectively), while under DH conditions by 22% lower plant Cr was found. Main nutrient status (P. K, Ca, Mg, S...) were independent on soil tillage. For this reason, usual fertilization practice is recommended for possible application of soil tillage reduction under conditions of calcareous chernozem

Reduced soil tillage systems for crop rotations improving nutritional value of grain crops

The trial for winter wheat ( Triticum aestivum L. ) or spring barley ( Hordeum vulgaris L. ) in rotation with maize ( Zea mais L. ) on lessive-pseudogley in semiarid to semihumid climate of Eastern Croatia was set up during years 1996–1999 with five soil tillage systems: PL) Conventional tillage based on ploughing; PD) Conventional tillage after diskharrowing for previous crop in preceding season; DP) Diskharrowing after conventional tillage for previous crop in preceding season; DD) Continuous diskharrowing, and CD) Chiselling and diskharrowing. During first and second season (1996/97 and 1997/98), recorded winter wheat grain yields were not different, with PL having the highest and DD the lowest yield. Maize showed next differences in first season: PL=PD>CH=DD=DP, and in second season PD=PL=DP=CH>DD. In 1999, spring barley replaced winter wheat, and yields were: PL>DP>PD>CD>DD. Maize yields recorded were: PL>PD>DP>CH>DD. The grain yield results, together with hectoliter mass and mass of 1000 grains, supported that PL can be replaced with other tillage systems for winter wheat and spring barley, whereas continuous diskharrowing may have substantially lower yields for maize during unfavourable years