1. Institute of Plant Nutrition, Leibniz University of Hannover, Herrenhäuserstr. 2, 30419 Hannover, Germany
2. University of Göttingen, Department of Crop Science – Quality of Plant Products, Carl‐Sprengel‐Weg 1, 37075 Göttingen, Germany
3. Universität Hohenheim, Landessaatzuchtanstalt (720), 70593 Stuttgart, Germany