Yield and flour quality of spring wheat as affected by soil tillage and animal manure

BACKGROUND: Yield and quality of organic bread wheat may be improved by adjusting tillage and type of manure. We tested two different tillage strategies (rotovation plus ploughing or ploughing only) before sowing spring wheat (Triticum aestivum L.) on a coarse loamy sand. The tillage strategies were combined with four nitrogen (N) rates of animal manure supplied in either slurry or liquid manure. RESULTS: Rotovation before ploughing had only a negligible influence on soil inorganic N content in the spring and on wheat biomass development. Liquid manure gave a higher protein and gluten content than slurry, probably due to its higher proportion of inorganic N. At low N rates, gluten from wheat supplied with slurry was softer than from wheat given liquid manure and responded differently to baking tests than expected from their gluten and protein content. At higher N rates, loaf volume corresponded well with the gluten and protein content. CONCLUSION: Soil tillage intensity did not have a major influence on soil N mineralisation patterns and manure N availability. Except at low N rates, the response of wheat flour to different types of animal manure is mainly determined by the amount of inorganic N supplied. (C) 2008 Society of Chemical Industry.