Résumé
The potential for improving wheat grain quality by management strategies involving crop rotation, catch crops, and organic manure was tested in organic long-term experiments in Denmark and Austria. Growing grass clover in a four-year rotation resulted in a higher wheat yield increase that could not be achieved by including leguminous catch crops in the rotation. Yield was also higher with a pre-crop of pea than of lucerne. The average protein concentration was 132 g kg(-1) for grains from the Austrian experiments while the Danish grains held 85 g kg(-1). Protein was generally much less affected by the experimental conditions than grain yield. None of the tested management parameters affected grain protein concentrations in the Danish experiment. In the Austrian trial, a significant pre-cropxtreatment interaction reflected a positive effect of the animal manure treatment on protein and dry gluten in wheat following pre-crop pea. Danish grains generally contained more soluble polymers of less interest for the baking process than the Austrian ones. The study emphasizes the challenges in improving the quality of organically grown wheat beyond what is predetermined by environmental growth conditions and cultivar. However, baking quality appeared better than could be expected from the quality parameters determined.