Winter wheat yield and quality related to tillage practice, input level and environmental conditions

The grain yield and end-use quality of winter wheat can be affected by the crop management system. A four year set of experiments, based on 13 winter wheat varieties and two locations in the Czech Republic, were designed to evaluate the interaction of two tillage systems (conventional ploughing to 22 cm depth and surface stubble ploughing to a depth of 8-10 cm) and two input (differing mainly in N fertilization and crop protection) on grain yield, protein yield and six grain quality traits. ANOVAs showed that location, year and variety had together with interactions between these factors the most significant effects on grain yield and quality parameters. Protein yield, protein content and wet gluten content were also highly affected by input level. Tillage effects on the examined traits were generally lower than the effects of environment, variety and input level and could be demonstrated conclusively in interaction with input levels. Under conventional tillage combined with a high input level, protein content, wet gluten content and Zeleny sedimentation volume were increased (respectively by 4.1, 5.0 and 6.2% compared to the means obtained under the high input reduced tillage system), while gluten index, falling number and test weight were not significantly affected. The decisive factor for protein yield was the input regime rather than the tillage strategy. The high input reduced tillage system (surface stubble-ploughing to a depth of 8-10 cm) resulted in a significant grain yield advantage over the high input conventional tillage system (4.6%). Reduced tillage combined with low inputs produced the poorest quality grain as measured by parameters based on protein content. Reduced tillage may help to stabilize production especially on soils prone to water stress. The varieties varied widely for their bread-making quality, but did not respond differentially to the management system. These results are informative for decision making purposes when an appropriate management regime is being sought for a particular environment. (C) 2013 Elsevier B.V. All rights reserved.