[1] Leibniz Inst Plant Genet & Crop Plant Res, D-06466 Gatersleben, Germany
[2] Univ Hohenheim, D-70593 Stuttgart, Germany
[3] Humboldt Univ, Inst Biol, D-10115 Berlin, Germany
[4] Scottish Crop Res Inst, Dundee DD2 5DA, Scotland
[5] Univ Stirling, Sch Biol & Environm Sci, Stirling FK9 4LA, Scotland